copied-pasted. If a planet is within the internal search area, the J2000, mean and apparent positions will be given.


Download from internet deep sky image defined by the square or near mouse position. HNSKY will store up to 9 images in the Documents directory as download1.fit, download2.fit.... After 9 files it overrides the first to prevent creating too many files. Normal DSSor DSS2 images are download as defined in the internet setting in menu SETTINGS tab 4.

For wide fields with a height above 3.5 degrees, Skyview provide the Axel Mellinger low resolution survey. The images are shown at any zoom and stored as downloadM1.fit, downloadM2.fit.... You can select in the internet setting in menu SETTINGS tab 4 an other survey like "HALPHA" or Mellinger colour green (MELL-G) or blue (MELL-B)

Furthermore the pop-up menu has the following menus:

Markers and lines
Telescope

To centre on an part of the display simply use "CENTRE ON":


To centre the map can be done in three other ways.

    1) Click the mouse wheel as a button,
    2) Pushing ALT KEY plus RIGHT or LEFT MOUSE button.
    ////3) Click twice with the LEFT mouse button.//// (remove 2018)

Mouse wheel:


Use the mouse wheel zoom in or out. To zoom in on a specific object, pull square box using the mouse while holding the left mouse button down. Use CTRL+Z to return to previous view. The distance and angle are give in the status bar. Clicking the mouse wheel as button will centre the map on that position

Keyboard:

Beside the ALT+key options for accessing the pull down menu items, the following hot keys are available in the pulldown menu:

General:	Command:	keys
General	Move left,right, up, down:	Arrow keys
	Move slowly left,right...:	CTRL+Arrow keys
	Zoom in:	CTRL+I or Alt-I or Page Down or Mouse scroll wheel. Ctrl + Page Down  or Shift + Mouse scroll wheel for small steps.
	Zoom out:	CTRL+O or Alt-O or Page Up or Mouse scroll wheel. Ctrl + Page Up  or Shift + Mouse scroll wheel for small steps.
	Zoom in, small step:	CTRL+Page Down
	Zoom out, small step:	CTRL+Page Up
	Search:	CTRL+F or Alt-S
	Reset:	Alt-R
	Objects menu:	CTRL+B or Alt-B
File	Save Status:	CTRL+W
	Load	CTRL+L
	Load event	CTRL+F
	Settings:	CTRL+E
	Supplement 1:	CTRL+1
	Supplement 2:	CTRL+2
	Supplement 3:	CTRL+3
	Supplement 4:	CTRL+4
	Supplement 5:	CTRL+5
	Print white sky:	CTRL+P
	Copy the window:	CTRL+C (as Windows copy)
	Exit	CTRL+X
Screen	Move To	CTRL+M
	North:	shift+N shift !!!
	South:	shift+S
	East:	shift+E
	West:	shift+W
	Zenith:	shift+Z
	Flip Horz:	CTRL+H
	Flip Vert:	CTRL+V
	Grid RA/DEC:	CTRL+G
	Grid Alt/Az:	CTRL+A
	Constellations:	CTRL+K
	Boundaries:	CTRL+U
	Animation	CTRL+R
	North always Up	CTRL+N
	Cross hair:	CTRL+Alt+H
	Pointing circles	CTRL+Q
	Draw solar object tracks:	INS
	Undo view:	CTRL+Z
	Redo view:	SHIFT+CTRL+Z
Date	System Time:	CTRL+T
	Now (time&date):	F9
	Enter Date Time:	CTRL+D
	Step one minute:	F3, F4 ("ACTUAL TIME" should be off)
	Step one hour:	F5, F6 or +, - key
	Step one day:	F7, F8
	Step 23:56:	F11,F12 or CTRL and + ,CTRL and - key
	Step 23:56 hours. This is very useful when monitoring a solar object over a long period while the star field reins stationary.

Some areas in the canvas can be clicked on. If a field is active, the mouse pointer will change to the standard arrow. There is an area at "date" to change the date, "position" to move to an other position.
/////If you want to know when an object is in the zenith, hold the mouse steady at the rise and set times. See below:////
remove 2018)

Copy object information in the clipboard.


After an object information is displayed, it can be copied to the clipboard by clicking on the status bar. Abbreviations are unconverted from the deep sky database.


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SETTINGS, tab Settings


Location use: This one should be selected for accurate positions of planetary object.

Equinox: Select for the map equinox J2000. The telescope equinox will be set by ASCOM. The equinox 2000 is the common reference frame for maps and this one should normally be selected. An

Jupiter GRS offset, this setting allows to correct transit time of Jupiter's great red spot, the GRS. The GRS is a cloud feature, and like any other cloud feature, it moves slowly around the planet.  Jupiter doesn't rotate as a solid object; clouds near the equator rotate a little faster than those closer to the poles. HNSKY uses a estimate for calculating the transit times but slowly an offset will occur which could be compensated using this setting.  Up to date transit times based on resent observations can be obtained from the web. E.g. https://www.projectpluto.com/jeve_grs.htm

Documents path indicates where the FITS, supplements en cache files are stored. See requirements. This is normally the "hnsky" folder in the Documents folder. The installer will normally place user files in this folder. If this folder is not available, it will alternatively it will look for the files in the program folder. Note that under Win10 writing in the program folder is not possible and could block downloading DSS images and accessing online star databases unless the permissions of the HNSKY program folder are modified. So it is better to have the "hnsky" folder in the Documents folder.

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SETTINGS, tab Colors

Colors: The grid, constellations, solar and deep sky colors and font size can be set in the menu "SETTINGS"(CTRL+E) of main menu "FILE".

Go to "PAGE" colors and just click with the mouse on the colors to change them.

The menu colors as any other window application are defined in your Windows set-up. To change these color settings, select "SCREEN" in your Windows set-up.

All these settings become permanent after selecting "SAVE STATUS" in menu "FILE".

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SETTINGS, tab Internet access


These settings normally don't require any change.

The only thing you could change are parameters. You could change DDS2R (Second Deep Sky Survey red) to DSS2B (blue) or DSSR (First survey red). Each provider has a slightly different interface so changing the provider will not work.

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SETTINGS, tab Update


From this tab the asteroid and comet database can be quickly updated. Same is possible within the editor.

The internet address for the asteroid ephemerides database (The SKY format) contains the current year. HNSKY will update the year in the path automatically based on the computer clock. In the first days of a new year it is possible that the update is not available yet from the minor planet center webpage. Is this the case, modify manually the year to the previous year. Note you can also the numerical integration option in the asteroid editor to update the ephemerides data.

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SETTINGS, tab telescope

There a three interfaces to control a telescope:

ASCOM: For Windows users the easiest way is to select ASCOM and install ASCOM  and ASCOM mount driver for your telescope.

ALPACA: To control a telescope remotely through a netwerk you could select ALPACA. On the remote computer you have to install both 

The INDI client is used for settings of  the telescope mount driver. Most mount drivers have a simulation mode which can be set for testing. To use the simulation mode of the mount driver you have to set it "ON" in the INDI client before it is possible to connect the mount.  You could also use the generic telescope simulator for testing.



The Indi client.

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Markers and lines


The "MARKERS AND LINES" allows you to draw deep sky outlines or your personal horizon and are stored in supplement 2.

Usage:

- Click on an existing object to use that name. (optional)
- Activate "DRAW LINES (Ra/DEC)"
- Click on the outlines of a deep sky object. Each time a line will be drawn.
- When finished deactivate "DRAW LINES (Ra/DEC)"
- Open supplement 2 and save outline as a .SUP file.
- When required last lines can be deleted with "DELETE LAST POINT".

Any change is not saved and requires a manual save of supplement 2 !!

Editing commands:

Line colour change mode: After activating this mode, hit the end point of a line and on every click the colour changes.

Insert line mode: After activating this mode, hit the end point of a line and on next click an extra line is inserted at that next point.

Remove line mode: After activating this mode, hit the end point of a line and the line is marked as comment with ;$$$ in front.

Hide line: After activating this mode, hit the end point of a line and the line command is changed from "line to =-1 to "move to"=-2 or the other way around. Works also for Az/Alt lines.

Be aware the the line commands are a series. For example these three commands will draw two lines:
1) "move to point A", 2) "line to point B", 3) "line to point C".

If you remove a start point of a constellation e.g. "move to point A", A new line from somewhere will pop-up to "point B". You have to apply the hide line on "point B" to make it a "move to point B" to remove this line.

Mosaic design
It is possible to draw and export rectangles to design a mosaic imaging session. See topic

.



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Sidereal or terrestrial view


1) Sidereal view off (=Terrestrial view:
- Stars rotate around celestial north (Polaris) as time goes by.
- Altitude and horizon grid are fixed as time goes by.
- RA/DEC grid follows stars and rotates around the celestial north as time goes by.
- In the short term solar objects are going around similar as stars.

Terrestrial view is what you see if you just look to the sky and is caused by the rotation of the earth.

2) Sidereal view on:
- Stars are fixed on the map as time goes by
- Altitude and horizon grid rotate as time goes by.
- RA/DEC grid is fixed.
- Solar objects are moving slowly on the fixed map.

Sidereal view is what you see through the telescope while having the sidereal drive on. The so called diurnal motion of stars is off.

3) In the third option is to follow planetary object in the Animation Menu.

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Animation of planetary objects


To activate this menu, select via menu "SCREEN", "ANIMATION" (Ctrl+R). You could activate and use the animation button in the menu.

The animation menu handles three topics:

1) Object to follow: Follow a planetary object or the stars (sidereal) or nothing (terrestrial view) while time changes.

2) Time step: Change the time in a single or many steps. The many steps or animation are started with the "<<" or ">>" button. If tracks is activated the planets make a track for every step. The forward animation ">>" can be also started with key "INS" (or with menu "SCREEN", "INSTRUMENTS", "DRAW SOLAR OBJECTS")

3) Find an eclipse or occultation: This will show for your location the next or previous eclipses or occultation s. For the lunar option, all planets and the bright star Aldebaran are checked against the Moon position. For the solar option, the position if the Moon, Mercury and Venus are checked against the Sun position. The date and time show are just for the start of the phenomena.

The solar combo box list list will be filled with up to 10 object names where you click on.

To make animated movies, you should use an additional screen recorder program.
if you want to make a movie of Jupiter and its moons do the following:

    1) Lock on Jupiter by typing or clicking on Jupiter and activated option "Solar".
    2) Set the date to the beginning of the event.
    3) Select a small step size e.g. 1 minute and duration of 500 steps.
    4) Hit the ">>" or key "INS" to animate.

It could be beneficial the orientate the top of the MAP to the North by menu "SCREEN", "NORTH ALWAYS UP" (Ctrl+Alt+N)

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Telescope control



HNSKY can work together with ASCOM, a free third party telescope interface. ASCOM has drivers for almost any telescope. First you have to download and install the ASCOM program from http://ascom-standards.org

As soon you activate the ASCOM interface by the right mouse button pop-up menu or CTRL+7, the ASCOM window will pop-up. This window will allow telescope selection. For testing purposes you could select the ASCOM telescope simulator. Please select "Telescope simulator for .NET" rather then the older "Simulator".

Equinox: The telescope position will become visible as a cross. For maximum accuracy, the telescope and HNSKY should communicate in the same coordinate system. See menu SETTINGS (CTRL+E), setting EQUINOX, TELESCOPE. Most controlled telescopes communicate in "mean equinox of date" coordinates. HNSKY normally sets this automatically by reading from the telescope the equinox used using the ASCOM protocol. In this case you will not be able to change the telescope equinox and the correct equinox for communication will be used. Depending on the indication in your telescope you could select for the map either "mean equinox of date" or J2000 till they indicate the same. See menu SETTINGS (CTRL+E).

Note that if a telescope is correctly polar aligned, the mechanical drive will follow this "equinox of date" as the earth rotation does the same. For this reason it is convenient to communicate in "mean equinox of date" coordinates rather then do a conversion in the telescope to a different epoch.

The telescope position is indicated in the top caption of the HNSKY window.

Note: The ASCOM simulator allows setting equatorial system communicated for testing purposes. HNSKY will follow.

The telescope pop-up menu has the following commands:

Telescope to here, slew the  telescope to mouse position.  Note that slew to an object can be done from the

astro photography tools as  APT & CCDciel .  To activate put a check mark in front of "use TCP/IP server" in the menu SETTNGS (CTRL-E).





Depending on the integration the remote host can:

• Centre the map on a position in HNSKY.
• Position a rectangle frame in the map.
• Show a FITS image with the correct size and orientation in the map. 

HNSKY provides to the remote host:

• Target position after clicking on a object.
• Can export the mouse position via the mouse pop-up menu:

The used server commands are described in section server

 

Orthographic or spherical projection method. The sky is projected on a sphere and in the middle of this sphere lies the Earth. You are observing from outside this sphere with the corrected left and right orientation. This projection method allows wide views almost to 180 degrees. Disadvantage near the edge there is a distortion.



At high zoom factors, both projections produce identical maps.

See also subject 'Saving and loading program status'

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Print screen.

Printing. The printing routine will rebuild and adapt the screen view to the printer resolution. Laser printers will produce sharp and good quality prints. The size of the window and monitor resolution are irrelevant.

From version 3.2.2b the size of the printed stars is no longer adapted to the DPI resolution of the printer. A low resolution of of 72 or 144 DPI will give the correct star size (a few pixels) for printing on paper. If you select 1200 DPI you will get much smaller stars (still a few pixels), more intended for zoom-able digital maps. You could use this for printing to PDF

The are two print options: Black stars on a white background or inverse white stars on a black background. If the print option "white background" is selected, the intensity of colors will be adopted accordingly. For example, a very bright yellow Moon in a black sky will be adapted to a white sky as very dark yellow Moon. Identical as white stars become black on a white background.

Another option is to copy the screen contains to the windows clipboard using CTRL+C or the menu option "COPY WINDOW TO CLIPBOARD" in the main menu "SCREEN". Then paste it (CTRL V) in your favourite graphic program for further processing as saving or printing. With this option the resolution is depending on the original HNSKY window size.

A third option is to use the standard Window feature to copy the complete window in the windows clipboard by using the ALT-PRINT SCREEN keys. This will capture the complete window including menu bar. Then paste it (CTRL+V) in your favourite drawing program.

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Deep sky observations help file.


Deep sky observations help file for use with the HNSKY planetarium program. It is a compilation of more then 10.000 visual observations by Steve Gottlieb, Steve Coe and Tom Lorenzin. In HNSKY after you found an object or clicked on it, just hit the F2 button and the CHM file will display the available observations of that object. Rather then F2, you can go the main menu HELP and select the second menu indicating the last object found. Or just look around in the index of the deepsky.chm file.

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Star databases and catalogues.

Here an overview of the available star database and accessible catalogues:

supplements can be freely modified in the main editor.  For convenience HNSKY provides and additional edit menu to access a single entry:



After an object/entry of a supplement is found, it is possible to edit the entry by moving&click the mouse in the info area at the left top of the screen. In the field "type" additional info as a log could be entered. Select "Save suppl" to make the change permanent. This works only for supplements not for the database(s).


New entry:

	1.559949,,, 30.381647,,,,_56/2017-08-06    ,Log/Seen with 8 inch telescope. Bright star or blob ?,-99

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Spectral types of stars.

The spectral types of stars are defined with two characters. The first defines the main spectral type as follows:

Class letter	Temperature	Conventional color description	Actual apparent color
O	≥ 30,000 K	blue	blue
B	10,000–30,000 K	blue white	deep blue white
A	7,500–10,000 K	white	blue white
F	6,000–7,500 K	yellow white	white
G	5,200–6,000 K	yellow	yellowish white
K	3,700–5,200 K	orange	pale yellow orange
M	2,400–3,700 K	red	light orange red

The main types grade are subdivided decimally as: A0, A1, A2, A3, A4, A5, A6, A7, A8, A9, F0, ....
There are also some special spectral types as R, N, S, C for the carbon stars, W for the Wolf-Rayet stars and Q for novae

For more information, https://en.wikipedia.org/?title=Stellar_classification

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The Saguaro Astronomy Club or SAC deep sky database.

The Saguaro Astronomy Club or SAC deep sky database contains as good as all deep sky objects visible in amateur telescopes.
The SAC compilation of data was begun in an effort to provide a comprehensive observing list for use at the telescope. Their data is released for private use by anyone who wishes to use this database.
Please do not sell this database in any form. The database in ASCII format can be download from their web pages.
The HNSKY database is a compilation of the SAC DEEP SKY DATABASE VERSION 8.1 and Wolfgang Steinicke NGC/IC database.

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The "Smithsonian Astrophysical Observatory Star Catalog" (SAO, SAO Staff 1966).

HNSKY is using the updated and corrected version from May 1991, available from the CDS. This star catalog is complete to magnitude 9.0 but in some areas the limiting magnitude was raised to magnitude 10. The original ASCII format is converted to the HNSKY format

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Catalogue of Positions and Proper Motions (PPM) north, south.

A convenient, dense, and accurate net of astrometric reference stars that represents the new IAU (1976) co-ordinate system on the sky.

Compiled by Roeser S., Bastian U.

    - PPM North Star Catalogue (181731 stars, 1988)
    - PPM South Star Catalogue (197179 stars, 1992)

Since its appearance in 1966, the SAO Catalogue (SAO, 1966) has been the primary source for stellar positions and proper motions. Typical values for the rms errors are 1 arc sec in the positions at epoch 1990, and 1.5 arc sec/century in the proper motions. The corresponding figures for the AGK3 (Heckmann et al., 1975) on the northern hemisphere are 0.45 arc sec and 0.9 arc sec/century. Common to both catalogues is the fact that proper motions area derived from two observational epochs only. Both catalogues are nominally on the B1950/FK4 co-ordinate system.

The PPM Star Catalogue (Roeser and Bastian, 1991, Bastian et al., 1993; for a short description see Roeser and Bastian, 1993) effectively replaced these catalogues by providing more precise astrometric data for more stars on the J2000/FK5 co-ordinate system. Compared to the SAO Catalogue the improvement in precision is about a factor of 3 on the northern and a factor of 6 to 10 on the southern hemisphere. In addition, the number of stars is increased by about 50 percent. Typical values for the rms errors on the northern hemisphere are 0.27 arc sec in the positions at epoch 1990, and 0.42 arc sec/century in the proper motions. On the southern hemisphere PPM is much better, the corresponding figures being 0.11 arc sec and 0.30 arc sec/century. The PPM catalogues (ftp://cdsarc.u-strasbg.fr/cats/I/146, ftp://cdsarc.u-strasbg.fr/cats/I/193) are available in ASCII format from the Centre de Données astronomiques de Strasbourg

Note: These ASCII catalogues can't be accessed by HNSKY directly conversion. Converted version is already available!

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Catalogue of Positions and Proper Motions (PPM) supplements.

==The 90000 Stars supplement to the PPM Star Catalogue (89676 stars,1994)==

The improvement over the SAO Catalogue was made possible by the advent of new big catalogues of position measurements and by the inclusion of the century-old Astrographic Catalogue (AC) into the derivation of proper motions (for a description of AC see Eichhorn, 1974). But even PPM does not fully exploit the treasure of photographic position measurements available in the astronomical literature of the last 100 years. The Astrographic Catalogue contains roughly four million stars that are not included in PPM. For most of them no precise modern-epoch position measurements exist. Thus it is not yet possible to derive proper motions with PPM quality for all AC stars. But among the 4 million there is a subset of some 100,000 CPC-2 stars that are not included in PPM. These stars constitute the 90,000 Stars supplement to PPM.

==The Bright Stars Supplement (275 stars, 1993)==

A number of bright stars is missing from the PPM Star Catalogue, both on the northern and on the southern hemisphere. The Bright Stars Supplement described here makes PPM complete down to V=7.5 mag. For this purpose it lists all missing stars brighter then V=7.6 mag that we could find in published star lists. Their total number is 275. Only 2 of them are brighter then V=3.5 This replaces the December 1992 edition of the Bright Stars Supplement which inadvertently contained 46 duplicates of stars already contained in the main parts of PPM.

The PPM supplement catalogues ftp://cdsarc.u-strasbg.fr/cats/I/208/ are available in ASCII format from Centre de Données astronomiques de Strasbourg

Note: These ASCII catalogs can't be accessed by HNSKY without conversion. Converted version is already available!

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New General Catalog (NGC).

Included in the main deep sky database.

The popular New General Catalog was compiled by the astronomer J.L.E. Dreyer (1852 - 1926) and contains information on 7,840 objects. Object types include galaxies, nebulae and clusters.

Index Catalog (IC)

The Index Catalog. By 1908 J.L.E. Dreyer compiled an additional list of 5,386 objects to his NGC catalog.

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Tycho-2 information.

The Tycho2++ is the standard star database used in the HNSKY program. Format is in the 290 format. It is made from the combined Tycho-2 and UCAC4 star catalogues free available from the CDS(Centre de Données astronomiques de Strasbourg) webpage. The Tycho-2++ contains 4,7 million stars if which 2.5 million Tycho stars and additional about 2.2 million UCAC4 stars to make it complete up to magnitude 12.5.

The reason the UCAC4 was not used completely is the poor magnitude value for some bright stars. This compilation was created by adding all UCAC4 star without an HIP, FK6 or Tycho label to Tycho-2. The only exception is the Polar star. This star was due to it's importance added manually. It is include in original Tycho-2 but without position and labelled with flag HIP source in UCAC4 so omitted in the automatic merge.

The star proper motion is not included, but an update with the correct epoch (currently 2017) will released.

The star labels of both the Tycho-2 and UCAC4 stars, magnitude and accurate position are preserved in the very compact HNSKY format of 11 bytes only. See .290 format description.

Total size of Tycho-2++ is about 46 Mbyte. Up to magnitude 7 it contains 147 UCAC4 stars and up to magnitude 10 it contains only 336 UCAC4 stars.

Abstract:

The Tycho-2 Catalogue is an astrometric reference catalogue containing positions and proper motions as well as two-colour photometric data for the 2.5 million brightest stars in the sky. The Tycho-2 positions and magnitudes are based on precisely the same observations as the original Tycho Catalogue (hereafter Tycho-1; see Cat. <I/239>)) collected by the star mapper of the ESA Hipparcos satellite, but Tycho-2 is much bigger and slightly more precise, owing to a more advanced reduction technique.

Components of double stars with separations down to 0.8 arc sec are included. Proper motions precise to about 2.5 mas/yr are given as derived from a comparison with the Astrographic Catalogue and 143 other ground-based astrometric catalogues, all reduced to the Hipparcos celestial coordinate system. Tycho-2 supersedes in most applications Tycho-1, as well as the ACT (Cat. <I/246>) and TRC (Cat. <I/250>) catalogues based on Tycho-1. Supplement-1 lists stars from the Hipparcos and Tycho-1 Catalogues which are not in Tycho-2. Supplement-2 lists 1146 Tycho-1 stars which are probably either false or heavily disturbed.

For more information, please consult the Tycho-2 home page: webpages

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The UCAC4 star catalog.

If you want star proper motion implemented or the original designation you could download the 113 million stars, 8.5 Gbytes large USNO UCAC4 from ftp://cdsarc.u-strasbg.fr/cats/I/322A/UCAC4/ HNSKY can access this catalog directly. Download Z001 to Z900 from the U4b directory and add to the same directory file u4index.unf from U4i. This is a catalog where HNSKY will use proper motion for maximum accuracy.

Link in menu SETTINGS to this U4b directory.

For more information download the readme files from the web Page mentioned above.

The magnitude error is larger then for the Tycho catalog. HNSKY will select the brightest value from "UCAC fit model magnitude", "UCAC aperture magnitude" and "B magnitude from APASS". The 2MASS unique star identifier is displayed in the status bar of HNSKY.

Here an example of NGC884 & NGC869 using the UCAC4:

Abstract:

UCAC4 is a compiled, all-sky star catalog covering mainly the 8 to 16 magnitude range in a single bandpass between V and R. Positional errors are about 15 to 20 mas for stars in the 10 to 14 mag range. Proper motions have been derived for most of the about 113 million stars utilizing about 140 other star catalogs with significant epoch difference to the UCAC CCD observations. These data are supplemented by 2MASS photometric data for about 110 million stars and 5-band (B,V,g,r,i) photometry from the APASS (AAVSO Photometric All-Sky Survey) for over 50 million stars. UCAC4 also contains error estimates and various flags. All bright stars not observed with the astrograph have been added to UCAC4 from a set of Hipparcos and Tycho-2 stars. Thus UCAC4 should be complete from the brightest stars to about R=16, with the source of data indicated in flags. UCAC4 also provides a link to the original Hipparcos star number with additional data such as parallax found on a separate data file included in this release.

The proper motions of bright stars are based on about 140 catalogs, including Hipparcos and Tycho, as well as all catalogs used for the Tycho-2 proper motion construction. Proper motions of faint stars are based on re-reductions of early epoch SPM data (-90 to about -20 deg Dec) and NPM (PMM scans of early epoch blue plates) for the remainder of the sky. These early epoch SPM data have also been combined with late epoch SPM data to arrive at proper motions partly independent from UCAC4 (Girard et al. 2011). The NPM data used in UCAC4 are not published. No Schmidt plate data is used in UCAC4.

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Example load event.

You have just have just adjusted the date at 2002-7-25, 3:30 UT and zoomed in to M1. Saturn is eclipsing M1. This event can be saved as"Eclipse of the Crab nebula by Saturn". To recall this event, justload this file as an event. The time of the event, position and zoom factor will be returned.

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Saving and loading program status.


Save status in the pull down menu "File" will save all your settings including your position on Earth, equinox, parallax, time zone, window size. These settings are stored in the file DEFAULT.HNS. After start-up these settings are loaded again automatically. Depending on your setting in main menu "SETTINGS", the program will start with the view at midnight or actual. The save/load option behaviour is different for high and low magnifications or zoom factors. For high zoom factors, the program will return the same RA/DEC as saved. Due to time differences, the view will be slightly rotated, unless load event to restore original time and date is used. For low zoom factors, the program will always return the same Azimuth/Altitude as saved. This is good for start-up overviews such as a wide view to the south.

Save as The program settings are saved in a different file then DEFAULT.HNS. "Save as" is a helpful tool to find and restore your favourite object.

Load status The saved status is restored. This will not (unless your load DEFAULT.HNS) effect your settings for position on Earth, equinox, parallax, time zone, window size and time settings)

Load event As load status but also the original time and date are restored.

Example load event

See also subject 'Projection method'

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Instruments and found markers.

Several instruments are available:



Several found markers are available:



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Program files.

The following files are part of the program:

Located in: C:\Program Files\hnsky:

hnsky.exe	Main program
sao_hsky.dat	Star database,SAO stars to magnitude 9.5
ppm_hsky.dat	The PPM star database and supplements to magnitude 10.0 (468861 stars)
tyc_*.290	Tycho-2 star database containing 2.5 million stars. .290 file format. (32 files).
Deep sky level 1.hnd Deep sky level 2.hnd Deep sky level 3.hnd	- Small deep sky databases with 267 selected objects. Good start for beginners. - Large deep sky database with 2600 objects. Up to magnitude 12. GX>=1 arc min. - Very large deep sky database with 26000 objects. Up to magnitude 15.5. GX>=1 arcsin.
deepsky.chm	Deep sky help file containing more then 10.000 deep sky observations by Steve Gottlieb, Steve Coe and Tom Lorenzin.
*.ini	Non English menu translation files

Located in: Documents\hnsky

hns_com.cmt	The comet database.
hns_ast.ast	The asteroid database.
hns_****.sup	Several deep sky and star supplements files, in ASCII format. (Milky Way, Yale catalog, binary and variable stars, messier objects, world map.
*.hns	Setting and event files in ASCII format.you can load/save. During start-up 'default.hns is loaded'

Located in: Documents\hnsky\fits

*.fit

Several deep sky and planetary images in FITS format.

Located in: Documents\hnsky\cache

*.txt

Cache of online downloaded star catalogues UCAC4, Gaia DR2.

The above files locations are for v3.0.1 and higher
The Windows hidden "Application Data" directory is not used by purpose.

New fresh installations of the program will by default be placed in the "c:\Program Files\hnsky" directory. Existing installations will stay in the previous selected directory such as "c:\hnsky". If you want to move the new location, then save your default.hns settings file somewhere else, uninstall the old version, install the new version and copy & overwrite the default.hns file.

The following databases can be accessed directly if downloaded:

UCAC4 113 million stars, dated 2014

Instead of the above mentioned local UCAC4 you could access online:

UCAC4 (obsolete)

. Some obsolete translations are still available:  Italian, Romanian, Korean, Volunteers to update or create new translations are welcome.

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Personal menu shortcuts.

All non English versions including the English module have the possibility to add your personal menu shortcuts.

For example if you look inside the file ENGLISH.INI in HNSKY directory, you can modify the menu shortcuts. This looks like:

    savesettingsS   = CTRL+W
    loadS           = CTRL+L
    loadeventS      = CTRL+J
    locationS       = CTRL+E
    asteroideditorS = CTRL+1
    cometeditorS    = CTRL+2
   

All labels should be there. Removing them will result in blank menu items.

You could enter keys such as W or CTRL+W or Alt+W or CTRL+Alt+W. Single letters such a W (except F1, F2 ...) are not recommended, since they will block typing in the SEARCH menu.

To disable these files, delete or remove the *.ini file(s). The original English text and menu short cuts will return. You could also delete the settings file "default.hns" but you will loose all you settings including you position.

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Units and spectral types:

Brightness: Magnitude pro square arc minute.

Size: Size or diameter in arc minutes. In case an " is displayed, the diameter is in arc seconds (typical for planets)

Spectral types of stars:

The spectral types of stars are defined with two characters.

See also subject 'Database files of stars and deep sky objects'

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Accuracy of the program:

General remark: HNSKY has a high accuracy. To get comparable and correct ephemerides it is important to set:

    1) Geographical position on Earth correct.
    2) Time zone and day light savings. When necessary check the UTC time in the pull down menu "ABOUT". To get maximum moon and Sun accuracy, select ΔT correction on.
    3) Desired equinox. Normally J2000.
    4) Correction for parallax error on for topocentric values and off for geocentric values.

For 2) See subject 'ET and UT time'
For 2) For time zone of major cities see subject 'System time, time zone and location on Earth'

All positions of the Deep sky and planetary objects are astrometric referred to equinox J2000 (2000, January 1.5), equinox B1950, the mean equinox of the current date or apparent. These are the co-ordinates as they would appear to a stationary observer at the year 2000, 1950 or current date. Star positions in J2000 or B1950 may be compared directly with planet positions. The mean position is depending on the orientation of the earth of that epoch. The apparent position are the mean positions corrected for the velocity of the moving Earth aberration and wobble of the earth axis nutation. These aberration and nutations are effecting both stellar and planet positions equally (max. 30 arc seconds) and does no effect the displayed map.

The desired equinox can be selected via main menu "FILE" and then menu option "SETTINGS".

Date and time setting:


Enter the required date and time in the "set time" menu. The day of the month can be entered with fraction. So entering 30.5 will give day 30 at 12 noon.
It follows the astronomical year numbering including year 0. Historians did not use the Latin zero, nulla, as a year, so the year preceding AD 1 is 1 BC. So year -44 is "45 BC"

The build in monthly calendar doesn't allow a date beyond 1752 and 9999 so a parallel input is created.


Alternatively you could enter the date as Julian day in the JD tab.

Valid dates of the program :

The program has an internal analytical planetary solution which is accurate for dates between the year 1750 and 2250, except for Pluto, which is only accurate between 1890 and 2100. For a longer period or higher accuracy download the JPL Propulsion Laboratory Development Ephemeris DE430 or DE431. The DE431 covers the years -13000 up to 16999.

The internal analytical planetary solution is based on "Astronomy on the Personal Computer" by O. Montenbruck and T. Pfleger, 1998, English edition (Almost equal to 1993 edition). This is a very detailed book for Pascal programmers and contains several professionally written routines. The source code is on an attached disk. This book is not intended to be a teaching guide.

Ephemerides calculations for the moons of Mars, Jupiter, Saturn Uranus, and Neptune are based on their rotation period and their correct axis orientation (Theta) in space. Their rotation center position equals the planet position is known from the planet ephemerides. A basic X,Y,Z calculation is required to determine their final position in space. Their orbit is calculated as perfect circular, which is for the major moons more or less correct. Only for the Moons of Jupiter a correction for their gravitational interactions factors is made based on some factors found in the book of Meeus, Astronomical Algorithms edition 1991.

Accuracy of Planet and Moon ephemerides:

The internal ephemerides of the planets have a typical error of a few arc seconds with a maximum of about ten arc seconds. Only Neptune has a maximum error of about 40 arc seconds.

The internal ephemerides of the Moon are correct within about one arc second. It is important to select "ΔT correction" on to get accurate Moon eclipses. The resulting eclipse is correct within one maybe two minutes. The JPL Propulsion Laboratory Development Ephemeris should be spot on.

Rise and set time should be correct within, perhaps, two minutes. To get accurate rise and set times, the atmospheric refraction correction should be set "ON" (menu "SET EQUINOX AND LOCATION"). Light from objects close to the horizon is bent while passing through the atmosphere. Objects close to the horizon will appear to be higher then their actual position. At zenith, this effect is zero and increases towards the horizon. At an altitude of 45 degrees it is only 1 arc-minute. At an altitude of 10 degrees it is 5 arc-minutes and at the horizon it increases rapidly to about 35 arc-minutes.

See explanation of atmospheric refraction in the glossary

Note that the rise and set time are given for a date. So if the HNSKY time is at 2015-11-25 24:00 hours and the rise time is give as 00:05 hours it happens in the morning at 2015-11-25 00:05 hours and most likely for you in the past. Is the HNSKY time at 2015-11-26 00:00 hours, rise and set times are given for date 2015-11-26.

Moon ephemerides reference: In general, the positions of the moons of Mars, Jupiter, Saturn, Uranus and Neptune are displayed with an error of 10 arc seconds or less. As a reference the ephemeris values of the 'Bureau of Longitudes' in France, web address and the "Solar System Dynamics Group of JPL", web address were used.

Remarks:

- The parallax error can be corrected. To get the geocentric value instead of the topocentric value, switch correction for parallax "OFF".
- Error due to speed of light, velocity of planets is corrected.
- Rise and set time. They are all, except for the Sun and Moon, given for the center of the object. For the Sun and Moon it is given for the upper limb of the disk.

Accuracy of the star database:

Star motion (proper motion) is not implemented except for the USNO UCAC4 and

online Gaia DR2. The HNSKY version of the SAO database does not contain star motion. Star position is correct for Equinox and Epoch 2000. For any other date only the Equinox can (if selected) be recalculated to the equinox of the current date or 1950. This means that in the several decades, before and after the year 2000, the positions of a few stars will have small errors. These (nearby) stars will move slowly across the sky introducing an error in arc seconds. If this program is still in use after 50 years, an updated star database could be created.

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Angular measuring tools, mosaic design, found object markers.

Angular measuring tools:

In the main menu "SCREEN" there are four tools to measure and aim objects:

1) Cross-hair. Automatic adjusted circles for quick estimate of distances. The numbers in the cross-hair indicate the distance from the center (radius !!) of the cross-hair in degrees. The numbers are in line to the north.

2) Imaging sensor measuring frame. At the mouse cursor a rectangle box will be shown, default orientated North/South.

ALt & mouse scroll wheel for small rotation steps.

3) If the measuring frame is ON, you can draw rectangles  by pressing the HOME button. The J2000 or MEAN position is given and orientation. The rectangles can be removed by pressing CTRL+DEL (as defined in the markers and line menu) The rectangles are stored a one line (brightness=-8)  in supplement 2. Save supplement 2 to make is permanent. See next image.

4) Pointing device. This can be used as a simulation of an aiming device such as TelRad. It shows maximum 5 fixed size circles. These aiming devices such as Telrad consists of a glass plate through which you look at the sky, which project's three concentric red circles (typical 4, 2, and 0.5 degrees) "superimposed" on the sky. You simply move the telescope while looking at the sky through the Telrad finder until the circles are centred on the desired object.

5) Zoom box. While keeping left mouse button down and pulling with the mouse a zoom square, the distance and angle are give in the status bar. Make zoom box small afterwards to prevent zooming in or use CTRL+Z to return to previous view.

1.  Use right mouse button pop-up menu and select measuring frame is on. (size of measuring frame can be set in settings)
2. Set the angle correct if required with CTRL + mousewheel.
   
3. Move the mouse to the desired position and hit HOME button (or using the mouse pop-up menu) to add a frame.
4. Add more frames with the home button.
   
5. If required remove any frames with the mouse pop-up option "remove last line" (shortcut CTRL + DEL) or option "Delete lines"
6. If ready save the supplement 2 containing the frames.
7. Position and angle of the frames can be exported to the CCDCiel or APT imaging programs using the TCP/IP server link. For export all frames use the mouse popup menu. For one by one click on each frame center and the frame celestial position and angle can be retrieved in CCDCiel or APT.

Found object markers

As soon an object is found in the database it can be marked in three ways as set in main menu 'SCREEN', sub menu 'FOUND OBJECT MARKER':

    1) Two short lines orientated North-South.
    2) Pointing circle marker. This is very handy to make a field map with several of these circles.
    3) Name of object marker.
    4) Magnitude of object marker.

Then there is the special possibility to copy the object info into the clipboard so it can be passed into other Windows applications.

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Deep sky images from DSS and other.


Functionality: HNSKY can add deep sky images to the sky map. You can download them directly from the internet using the pop-up menu. This is the easiest and simplest method. You could add your own images. These images should be in the FITS format with the extension *.FIT *.FITS or *.FIT*. Each image should contain information about its position and pixel size and orientation in the so-called WCS format. HNSKY will read all FITS file as available and if required, plot them with the right size and orientation.

Images without the WCS keywords can't be used, unless you add them using a plate solver e.g. the online solver http://nova.astrometry.net/ or the  ASTAP  program. For more information see below "compatibility".

Filtering: The directory where HNSKY will look for FITS files can be set in SETTINGS. It will read all available 8, 16 bit or -32 float FITS files. If you have more then a few hundred FITS files, a file mask or filter could speed up the loading. Examples: 23*45*.FIT* or *_ORI.FIT*.

Image color: The color of the images is default red but can be set in one of the basic RGB colors in the menu SETTINGS, sub menu COLORS. The program supports also color FITS files but only in the format described below. Most color FITS images contain the three colors separate. You will need the program HNS_FV to create these files.



Background, Brightness: The FITS background and brightness are adjustable with the two sliders at the bottom of the OBJECT menu. Some deep sky DSS pictures are under-overexposed and need some fine-tuning to get maximum detail.

The first pixel in the DSS gets a hint containing the FITS file name and size. Normally that is the south-east corner.

Printing: Best printing results are obtained with a color printer. A black and white laser printer give less satisfactory results while the gray simulation spoils small details. In some cases a fixed map orientation to the North could improve plotting since the pixels are plotted as squares.

Compatibility: FITS images are very popular in astronomy and can contain all kinds of information but in our case just an image. The FITS (Flexible Image Transport System) files start with a pretty long information header, which in our cases should contain the image size, position and orientation in a subset of the so called WCS (World Coordinate System) format.

HNSKY will read FITS files containing the following WCS keywords:

    BITPIX  = 8, 16, 24, 32 bit integers, -32 ,-64 bit float
    NAXIS1  = Length X axis
    NAXIS2  = Length Y axis
    DATAMIN = Minimum valid value in the image
    DATAMAX = Maximum valid value in the image
    CRPIX1  = Refpix of X axis
    CRPIX2  = Refpix of Y axis
    CRVAL1  = RA at Ref pix in decimal degrees
    CRVAL2  = DEC at Ref pix in decimal degrees
    CDELT1  = RA pixel step in degrees
    CDELT2  = DEC pixel step in degrees
    CROTA2  = Rotation angle
   

Almost all DSS images contain in the header 2x20 DSS polynomial factors to calculate the pixel position with a high accuracy. These polynomials compensate for optical or plate non-linearities. These factors are not used in HNSKY.

Color FITS files can come in two types. They are using a third dimension for the RGB color information. HNSKY supports only the type where BITPIX=8 and NAXIS1=3 and does not support NAXIS3=3.

Example of a compatible FITS header:

    SIMPLE = T / Standard FITS format flag
    BITPIX = 8 / Bits per pixel
    NAXIS  = 3 / Number of dimensions
    NAXIS1 = 3 / Number of Colors
    NAXIS2 = 382 / Row length
    NAXIS3 = 255 / Number of rows
   

HNSKY uses this format for the coloured planetary images made with the program

• J2000: celestial coordinate system adapted to the mean earth pole and mean equator on 2000 Jan. 1.5 TD or 2000 Jan. 1 12:00 hours dynamical time or Julian date 2451545.0. It was fixed to the stars by the FK5 definition but now by its successor ICRS and based on set of distant extragalactic objects".  The ICRS axes are consistent, to better than 0.1 arcsecond, with the equator and equinox of J2000.0 defined by the dynamics of the Earth. However, the ICRS axes are meant to be regarded as fixed directions in space that have an existence independent of the dynamics of the Earth or the particular set of objects used to define them at any given time.  Modern positions are given in ICRS
  
• Mean equinox of date, coordinate system based on Earth mean pole and equator at the current date.
• Apparent coordinates,  as mean equinox of date but corrected for the velocity of the moving Earth aberration and wobble of the earth axis nutation. These aberration and nutations are effecting both stellar and planet positions equally (max. 30 arc seconds) and does no effect the displayed map.
• Galactic, coordinate system based on the Milky way.
• B1950, celestial coordinate system based on the earth pole and equator on 1949 Dec 31st 22:09 UT/ 1950, Jan. 0,9235 or Julian date 2433282.4235.

Designation: The star designation is stored in 32 bit integer named NR290. If the NR290 integer is positive, it contains an UCAC4 number. For UCAC4 the star zone is added as a multiply of $100000.  This allows $800 or 2048 zones and  $100000 or 1.048.576 stars. The UCAC4 contains maximum 286.833 stars in a zone and has 900 zones.

UCAC4 decoding:
      nr_regio:=(nr32store and $FFF00000) shr 20;{every 00 is 8 bits, so 5 zeros is 20 bits shift}
      nr_star:= (nr32store and $000FFFFF);

In case the NR290 integer is negative, the integer contains the Tycho/GSC label. After making the integer positive, the regional star number is stored in the lowest 2 bytes, the GSC/Tycho star region (1..9537) is stored in the highest 2 bytes except that if bit $40000000 is true, the Tycho specific extension is 2, else the Tycho extension is 1. The highest bit of star number at $00008000 is used for the Tycho-2 extension 3.

Tycho2 decoding
      nr_regio:=((-nr32store) and $3FFF0000) shr 16;
      nr_star:=(-nr32store) and $7FFF;

      if (((-nr32store) and $40008000)>0) then  {tycho extensions}
      begin
        if (((-nr32store) and $40000000)>0) then
         naam2:=naam2+'-2'
        else
         naam2:=naam2+'-3';
      end;

The sky is divided in 290 areas of equal surface except for the poles which are half of that size. The stars are stored in these 290 separate files and sorted from bright to faint. Each file starts with a header of 110 bytes of which the first part contains a textual description and the last byte contains the record size, 6, 7, 10 or 11 bytes. The source of the utility program to make star databases is provided.

The 290 area's look as follows:



The 290 area's:

The areas are based on an mathematical method described in a paper of the PHILLIPS LABORATORY called "THE DIVISION OF A CIRCLE OR SPHERICAL SURFACE INTO EQUAL-AREA CELLS OR PIXELS" by Irving I. Gringorten Penelope J. Yepez on 30 June 1992

First circles of constant declination are assumed. The first sphere segment defined by circle with number 1 has a height h1 from the pole and a surface of pi*sqr(h1).

If the second circle of constant declination has a sphere segment with a height of 3*h1 then the surface area of the second sphere segment is nine times higher equal pi*sqr(3*h1). If the area between circle 1 en 2 is divided in 8 segments then these eight have the same area as the area of the first segment. The same is possible for the third circle by diving it in 16 segments, then in 24, 32, 40, 48, 56, 64 segments. The area of the third segment is pi*sqr(5*h1), where 25 equals 1+8+16. So the sphere segments have a height of h1, 3*h1, 5*h1, 7*h1. The height of h1=1-sin(declination). All areas are equal area but rectangle. In HNSKY all area's are a combination of two except for the polar areas to have a more square shape especially around the equator. The south pole is stored in file 0101.290 Area A2 and A3 are stored in file 02_01.290, area A4 and A5 are stored in file 0202.290. The distances between the circles is pretty constant and around 10 to 12 degrees. The distance between the area centres is around 15 degrees maximum.

The declinations are calculated by arcsin (1-1/289), arcsin(1-(1+8)/289), arcsin (1-(1+8+16)/289), arcsin(1-(1+8+16+24)/289)...

In a table:

Area	ring	declination_min	declination_max	Areas_equal_size	HNSKY_area's
A1	0-1	-90	-85.23224404	1	1
A2-A8	1-2	-85.23224404	-75.66348756	8	4
	2-3	-75.66348756	-65.99286637	16	8
	4-5	-65.99286637	-56.14497387	24	12
	6-7	-56.14497387	-46.03163067	32	16
	7-8	-46.03163067	-35.54307745	40	20
	8-9	-35.54307745	-24.53348115	48	24
	7-8	-24.53348115	-12.79440589	56	28
	8-9	-12.79440589	0	64	32
	9-10	0	12.79440589	64	32
	10-11	12.79440589	24.53348115	56	28
	11-12	24.53348115	35.54307745	48	24
	12-13	35.54307745	46.03163067	40	20
	13-14	46.03163067	56.14497387	32	16
	14-15	56.14497387	65.99286637	24	12
	15-16	65.99286637	75.66348756	16	8
	16-17	75.66348756	85.23224404	8	4
	17-18	85.23224404	90	1	1
			Total	578	290

6) Format of the .dat star databases (SAO_HSKY.DAT and PPM_HSKY.DAT):

The internal HNSKY star databases comes in two binary formats. The .290 format and a single file type with extension .dat This type is intended for databases up to about a half million stars. File names ***_HSKY.DAT. In this format the spectral code is is available. Examples, The SAO (sao_hnsky.dat) up to to about magnitude 9.5 and the PPM (ppm_hnsky.dat) star database complete to about magnitude 10.

The .dat record format:

    type
    hnskyhdr = record
    nr1  : byte;
    nr2  : byte;
    nr3  : byte;
    ra7  : byte;
    ra8  : byte;
    ra9  : byte;
    dec7 : byte;
    dec8 : byte;
    dec9 : shortint;
    mag0 : shortint;
    spec0: byte;
    end;

The record size for one star is then 11 bytes. Stars in the files are sorted from bright to faint.

The SAO/PPM number is stored in three bytes. Range 0 to 256^3-1. The RA position is stored in three bytes. Range 0 to 256^3-1, equals 0 to 2*pi or 24 hours. The DEC is stored as a three bytes integer (two's complement), so one bit is used for the polarity sign. Used range - 128*256*256-1 to +128*256*256-1, equals -pi/2 to pi/2 or -90 to 90 degrees

The resolution of this three byte storage will be for RA: 360*60*60/((256*256*256)-1) = 0.077 arc seconds. For the DEC value it will be: 90*60*60/((128*256*256)-1) = 0.039 arc seconds

The magnitude is stored in one byte or shortint, Used range -127 to 127, equal -12,7 to 12,7. Stars with a magnitude 12.8 and higher are stored as -12.6 and lower.

The spectral type is stored in one byte as follows:

    const spectral
    array[0..1,0..15] of char=(('0','1','2','3','4','5','6','7','8','9','A','B','C','E','+',' '),
                               ('O','B','A','F','G','K','M','R','N','S','C','W','P','Q','+',' '));
    spectr[0]:=spectral[1,spec0 shr 4]; highest 4 bits of spec0 define main spectral type
    spectr[1]:=spectral[0,spec0 and $0F];lowest 4 bits of spec0 define range 0...9..

The first 10 records+1 (111 bytes) are not used for star data, but contain a file description in txt/ASCII. The stars are sorted from bright to faint.

The size of the database is in principle unlimited, but a bigger database will slow down the build-up of the display. The program reads the database from disk and after some calculations the data is written directly to the window. Therefore the memory requirements of the program are very low.

Star proper motion is not implemented. Epoch is corrected by issuing every few years a new version with a proper epoch.

Here is a example how Sirius is stored in SAO_HSKY.DAT:

    Sirius is SAO 151881, stored at position 6F as hex 49 51 02 (reverse)

    The RA position is stored as C3 06 48 equals: (195+6*256+72*256*256)*24/((256*256*256)-1)=6.75247662 hours equals: 6:45:8.9
    The DEC position is stored as D7 39 E8, equals: 215 57 -24. The DEC is then (215+57*256-24*256*256)*90/((128*256*256)-1)=-16.7161401 degrees equals -16d 42 58

So DEC is stored as a two's complement (=standard), three bytes integer. The algebraic value of the two's complement can be found of the summing weight of sign bit (+ or - 256*256*128 ) and other bits added positively only.

For example +90 degrees will be stored as FF FF 7F (reverse) and -90 degrees will be stored as 01 00 80 (reverse).
Reconstruction of -90 degrees is then (01 + 00*256 -128 *256*256)*90/((128*256*256)-1).
Or as ( 1*(2^0) + 0*(2^1)+ 0*(2^2)....0*(2^22)+ 1 * -(2^23) )*90/((128*256*256)-1)

The reconstruction of RA and DEC could be done as follows:

    ra2:=(ra7 + ra8 shl 8 +ra9 shl 16)*(pi*2 /((256*256*256)-1));
    dec2:=((dec9 shl 16)+(dec8 shl8)+dec7)*(pi*0.5/((128*256*256)-1));

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Supplements for deep sky objects, stars, lines, logbook and local horizon.

These flexible database supplements can be used by users to enter additional deep sky objects, stars, labels and local horizons. Sorting on magnitude is not required. By using the internal HNSKY editor you can check the syntax. Due to the format, the speed is lower then for the standard deep sky database. HNSKY can become slow when the number of objects is above 10000. File names HNS_****.SUP. The format is defined in the first comment lines of the provided samples and in supplement files. Lines starting with ; are interpreted as comments. For creating a new large supplement a spreadsheet could be handy. The result should be saved as *.csv format.

HNSKY can handle two supplements. They can contain a mixture of deep sky objects, stars, constellation lines, local horizon and logbook markers. Supplements are ordinary TXT files and can be modified inside HNSKY or any other editor. There are several examples available at the HNSKY webpage. A deep sky object could be entered as following line:

02,22.5,0,+42,21,0,101,NGC891,GX;old_position,131,120,20,22

The position of the galaxy NGC891 is at RA 02:22.5 and DEC +42 d 21. The magnitude is 10.1 and brightness is 13.1. The size is 12.0 x 2.0 arc minutes. The PA angle 22 degrees.

Under the editor tools menu there are two options to import a list of objects as a supplement.  Copy a piece of text containing deep sky names (e.g. webpage) and paste it. Any recognisable object name will be filtered out and object info from the HNSKY database will be added. It can be pasted as a label or  supplement line. Since HNSKY completes the data it is advisable to select first the deep sky database 3.


General description of supplements:

HNSKY supplement file for stars, deep sky objects and RA/DEC, AZ/Alt lines.

Deep sky mode:
   As soon the brightness value is given, (if unknown enter 999) the entry will
   be displayed as a deep sky object.

Star mode:
   As soon brightness=0 or a text description is given or nothing at brightness
   field the entry will be displayed as a star. The brightness field can be used for
   additional information. If the brightness text is too long, split it with
   the symbols ; or / or |. If the object is found, this the full text will be
   displayed in the status bar, however only the first part will be displayed in
   the screen top&left message.

Line mode:
   1) RA/DEC  To draw RA, DEC lines enter brightness=-2 to move to and -1 to draw
             line to. The line color is defined by the magnitude see below.
             To enter a RA, DEC based label, enter brightness=-99. This will also
             disable the hint. if the RA, DEC based label requires an hints enter
              brightness=-98.

   2) AZ/ALT  To draw azimuth, altitude lines enter brightness=-4 to move to and
             -3 to draw line to.
             The line color is defined by the magnitude. See below.
             To draw circles in azimuth, altitude enter brightness=-5
             To get a azimuth/altitude based label+hint enter the name.

   In the RA/DEC or AZ/ALT line mode the color can be set by the magnitude parameter.
   mag value -20 is the horizon color, -21 is bright deep sky, -22 medium, -23 faint,
   -24 is constellation boundary color, -25 is cross_hair and finally else
   (mag=0 or empty) constellation color.


All numbers are read as floating point. So RA of 23:30:00 could be entered as
23,30,0 or as 23.5,0,0 or as 0,1410,0   (RA minutes is 23.5*60)
Dec sign will be based on + or - sign of Dec hours. + or - sign of minutes and
seconds are ignored.
Lines starting with a semicolon = ; will be ignored.

General format:

RA[0..24.0],RAM[0..60.0],RAS[0..60.0],
   DEC[-90.0..90.0],DECM[0..60.0],DECS[0..60.0],
      mag[*10],
         name/secondname[ASCII],
            type[ASCII],
               brightness[*10],
                  length[min*10],
                     width[min*10],
                       orientation[degrees]

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Visual and photographic field of view.



Visual field of view:The true angular diameter of the field as seen true the telescope is mainly depending on the magnification and the apparent field of the eyepc. For a plössl with apparent field of about 50° the angular diameter is equal to 50°/magnification.

Visual field of view for a telescope with a focal length of 2000 mm:

Eye PC	Magnification	Type Plössl (50°)	Type Wide angle (67°)
40 mm	50 x	53'(44°)	80'
25 mm	80 x	38'	50'
20 mm	100 x	30'	40'
16 mm	125 x	24'	32'
10 mm	200 x	15'	20'
7 mm	286 x	10'	14'

Visual field of view for a telescope with a focal length of 1250 mm:

Eye PC	Magnification	Type Plössl (50°)	Type Wide angle (67°)
40 mm	31 x	85'(44°)	130'
25 mm	50 x	60'	80'
20 mm	63 x	48'	64'
16 mm	78 x	38'	52'
10 mm	125 x	24'	32'
7 mm	179 x	17'	22'

Visual field of view for a telescope with a focal length of 580 mm:

Eye PC	Magnification	Type Plössl (50°)	Type Wide angle (67°)
40 mm	15 x	176'(44°)	286'(exit pupil 6.7 mm)
25 mm	23 x	130'	175'(exit pupil 6 mm)
20 mm	29 x	103'	139'
16 mm	36 x	83'	112'
10 mm	58 x	52'	69'
7 mm	83 x	36'	48'

Note: 40 mm, 1-1/4" Plössl have a field of view of 44° only.

Photographic field of view: For a telescope with a 24 mm sensor, the size of photographed part of the sky will be as follows:

Focal length instrument	Photographic field of view for 24 mm sensor
50mm	1600' (' = arc min)
100mm	800'
200mm	400'
500mm	160'
1000mm	80'
2000mm	40'

Table of visual limiting magnitudes under a very dark sky:

Telescope aperture	Limiting magnitude (Visual)
7x50 Bin.	9
10x70 Bin.	10
6 inch	14.1
8 inch	14.7
10 inch	15.1
12 inch	15.4
14 inch	15.7
16 inch	16.0

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Sun and planet & moon data:

	MERCURY	VENUS	EARTH	MOON	MARS	JUPITER	SATURN	URANUS	NEPTUNE
Mass 1024kg)	0.330	4.87	5.97	0.073	0.642	1898	568	86.8	102
Diameter(km)	4879	12,104	12,756	3475	6792	142,984	120,536	51,118	49,528
Density (kg/m3)	5427	5243	5514	3340	3933	1326	687	1271	1638
Gravity (m/s2)	3.7	8.9	9.8	1.6	3.7	23.1	9.0	8.7	11.0
Escape Velocity (km/s)	4.3	10.4	11.2	2.4	5.0	59.5	35.5	21.3	23.5
Rotation Period (hours)	1407.6	-5832.5	23.9	655.7	24.6	9.9	10.7	-17.2	16.1
Length of Day (hours)	4222.6	2802.0	24.0	708.7	24.7	9.9	10.7	17.2	16.1
Distance from Sun (106 km)	57.9	108.2	149.6	0.384*	227.9	778.6	1433.5	2872.5	4495.1
Perihelion (106 km)	46.0	107.5	147.1	0.363*	206.6	740.5	1352.6	2741.3	4444.5
Aphelion (106 km)	69.8	108.9	152.1	0.406*	249.2	816.6	1514.5	3003.6	4545.7
Orbital Period (days)	88.0	224.7	365.2	27.3	687.0	4331	10,747	30,589	59,800
Orbital Velocity (km/s)	47.4	35.0	29.8	1.0	24.1	13.1	9.7	6.8	5.4
Orbital Inclination (degrees)	7.0	3.4	0.0	5.1	1.9	1.3	2.5	0.8	1.8
Orbital Eccentricity	0.205	0.007	0.017	0.055	0.094	0.049	0.057	0.046	0.011
Axial Tilt (degrees)	0.01	177.4	23.4	6.7	25.2	3.1	26.7	97.8	28.3
Mean Temperature (C)	167	464	15	-20	-65	-110	-140	-195	-200
Surface Pressure (bars)	0	92	1	0	0.01	Unknown*	Unknown*	Unknown*	Unknown*
Number of Moons	0	0	1	0	2	67	62	27	14
Ring System?	No	No	No	No	No	Yes	Yes	Yes	Yes
Global Magnetic Field ?	Yes	No	Yes	No	No	Yes	Yes	Yes	Yes
	MERCURY	VENUS	EARTH	MOON	MARS	JUPITER	SATURN	URANUS	NEPTUNE

Source and more information: http://nssdc.gsfc.nasa.gov/planetary/factsheet/
See also: https://en.wikipedia.org/wiki/Solar_System

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Comet and asteroid (minor planet) ephemerides:


The Comet and Asteroid routine use both an ASCII file which can be accessed and updated under the main menu "FILE" and then "COMET DATA EDITOR" or "ASTEROID DATA EDITOR", sub menu "TOOLS", option




























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Assigning of Greek letter to stars according Bayer.

Activating Bayer designations in HNSKY:

To activate Bayer designations, the menu function "Name all stars" in OBJECTS and "constellations" in SCREEN should be both on.

Bayer system of star designations:

In the year 1603, Bayer assigned to each constellation star a letter of the Greek alphabet, beginning usually with Alpha for the brightest, Beta for the second brightest, Gamma for the third, and so on till Omega. In a few cases however, as in the Ursa Major, order of position was used instead of order brightness. The Greek letter is followed by the name of the constellation written in the possessive or genitive form.

Examples: Alpha Lyrae, Beta Cephei.

Here is the Greek alphabet:

Letter	Name	Letter	Name
Α α	alpha	Ν ν	nu
Β β	beta	Ξ ξ	xi
Γ γ	gamma	Ο ο	omicron
Δ δ	delta	Π π	pi
Ε ε	epsilon	Ρ ρ	rho
Ζ ζ	zeta	Σ σ/ς	sigma
Η η	eta	Τ τ	tau
Θ θ	theta	Υ υ	upsilon
Ι ι	iota	Φ φ	phi
Κ κ	kappa	Χ χ	chi
Λ λ	lambda	Ψ ψ	psi
Μ μ	mu	Ω ω	omega

An other system devised by Flamsteed is using numbers. This is not supported by HNSKY. Examples: 23 Orionis, 89 Virginis.

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Abbreviations used for the visual deep sky description according Dreyer and others.

The visual description of the deep sky objects used in SAC are from the NGC, some prominent amateurs, back issues of Deep Sky Magazine, Astronomy magazine, Sky and Telescope magazine and Burnham's Celestial Handbook. The descriptions are written down using the abbreviations from the NGC and Burnham's. HNSKY will in most cases translate/decode the abbreviations.



In some cases it will not be able to translate and will give the original abbreviation. The abbreviations used are given below:

!	remarkable object	!!	very remarkable object
am	among	n	north
att	attached	N	nucleus
bet	between	neb	nebula, nebulosity
B	bright	P w	paired with
b	brighter	p	pretty (before F,B,L or S)
C	compressed	p	preceding
c	considerably	P	poor
Cl	cluster	R	round
D	double	Ri	rich
def	defined	r	not well resolved, mottled
deg	degrees	rr	partially resolved
diam	diameter	rrr	well resolved
dif	diffuse	S	small
E	elongated	s	suddenly
e	extremely	s	south
er	easily resolved	sc	scattered
F	faint	susp	suspected
f	following	st	star or stellar
g	gradually	v	very
iF	irregular figure	var	variable
inv	involved	nf	north following
irr	irregular	np	north preceding
L	large	sf	south following
l	little	sp	south preceding
mag	magnitude	11m	11th magnitude
M	middle	8...	8th magnitude and fainter
m	much	9...13	9th to 13th magnitude

If you have never dealt with the NGC abbreviations before, perhaps a few examples will help

NGC	Describtion	Decoded descriptions
214	pF,pS,lE,gvlbM	Pretty faint, pretty small, little elongatedgradually very little brighter in the middle
708	vF,vS,R	Very faint, very small, round
891	B,vL,vmE	Bright, very large, very much elongated
7009	!,vB,S	Remarkable object, very bright, small
7089	!!B,vL,mbMrrr,starsmags13.....	Extremely remarkable object, bright, verylarge, much brighter middle, resolved,stars 13th magnitude and dimmer
2099	!B,vRi,mC	Remarkable object, bright, very rich, much compressed
6643	pB,pL,E50,2stp	Pretty bright, pretty large,elongated in position angle 50 degrees, two stars preceding

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Constellations short names and positions

Abbreviation	Name	Ra [hours]	Dec [degrees]	Genitive
And,	Andromeda	1	39	Andromedae
Ant,	Antlia	10	-34	Antliae
Aps,	Apus	16	-80	Apodi
Aqr,	Aquarius	23	-11	Aquarii
Aql,	Aquila	20	3	Aquilae
Ara,	Ara	17	-52	Arae
Ari,	Aries	3	23	Arietis
Aur,	Auriga	6	42	Aurigae
Boo,	Bootes	15	32	Bootis
Cae,	Caelum	5	-39	Caeili
Cam,	Camelopardalis	6	72	Camelopardalis
Cnc,	Cancer	8	24	Cancri
CVn,	Canes_Venatici	13	42	Canum Venaticorum
CMa,	Canis_Major	7	-23	CanisMajoris
CMi,	Canis_Minor	8	7	CanisMinoris
Cap,	Capricornus	21	-20	Capricorni
Car,	Carina	8	-57	Carinae
Cas,	Cassiopeia	1	60	Cassiopeiae
Cen,	Centaurus	13	-44	Centauri
Cep,	Cepheus	22	73	Cephei
Cet,	Cetus	2	-7	Ceti
Cha,	Chamaeleon	12	-80	Chameleontis
Cir,	Circinus	15	-68	Circini
Col,	Columba	6	-37	Columbae
Com,	Coma_Berenices	13	23	Comae Berenices
CrA,	Corona_Australis	19	-41	Coronae Australis
CrB,	Corona_Borealis	16	33	Coronae Borealis
Crv,	Corvus	12	-18	Corvi
Crt,	Crater	11	-13	Crateris
Cru,	Crux	13	-61	Crucis
Cyg,	Cygnus	21	50	Cygni
Del,	Delphinus	21	12	Delphini
Dor,	Dorado	5	-64	Doradus
Dra,	Draco	18	66	Draconis
Equ,	Equuleus	21	8	Equulei
Eri,	Eridanus	4	-17	Eridani
For,	Fornax	3	-27	Fornacis
Gem,	Gemini	7	26	Geminorum
Gru,	Grus	22	-46	Gruis
Her,	Hercules	17	31	Herculis
Hor,	Horologium	3	-52	Horologii
Hya,	Hydra	9	-11	Hydrae
Hyi,	Hydrus	3	-72	Hydri
Ind,	Indus	21	-53	Indi
Lac,	Lacerta	23	47	Lacertae
Leo,	Leo	11	18	Leonis
LMi,	Leo_Minor	10	33	Leonis Minoris
Lep,	Lepus	5	-19	Leporis
Lib,	Libra	15	-15	Librae
Lup,	Lupus	15	-42	Lupi
Lyn,	Lynx	8	48	Lyncis
Lyr,	Lyra	19	41	Lyrae
Men,	Mensa	6	-80	Mensae
Mic,	Microscopium	21	-36	Microscopii
Mon,	Monoceros	7	-5	Monocerotis
Mus,	Musca	12	-70	Muscae
Nor,	Norma	16	-52	Normae
Oct,	Octans	22	-85	Octantis
Oph,	Ophiuchus	17	-3	Ophiuci
Ori,	Orion	6	5	Orionis
Pav,	Pavo	19	-65	Pavonis
Peg,	Pegasus	23	20	Pegasi
Per,	Perseus	4	45	Persei
Phe,	Phoenix	1	-48	Phoenicis
Pic,	Pictor	5	-52	Pictoris
Psc,	Pisces	1	15	Piscium
PsA,	Piscis_Austrinus	22	-31	Piscis Austrini
Pup,	Puppis	8	-32	Puppis
Pyx,	Pyxis	9	-29	Pyxidis
Ret,	Reticulum	4	-60	Reticuli
Sge,	Sagitta	20	17	Sagittae
Sgr,	Sagittarius	19	-29	Sagittarii
Sco,	Scorpius	17	-36	Scorpii
Scl,	Sculptor	0	-35	Sculptoris
Sct,	Scutum	19	-10	Scuti
Ser,	Serpens_Caput	16	11	Serpentis
Ser,	Serpens_Cauda	18	-14	Serpentis
Sex,	Sextans	10	-2	Sextantis
Tau,	Taurus	4	17	Tauri
Tel,	Telescopium	19	-52	Telescopii
Tri,	Triangulum	2	32	Trianguli
TrA,	Triangulum_Australe	16	-66	Trianguli Australis
Tuc,	Tucana	24	-64	Tucanae
UMa,	Ursa_Major	10	57	Ursae Majoris
UMi,	Ursa_Minor	15	76	Ursae Minoris
Vel,	Vela	9	-49	Velorum
Vir,	Virgo	13	-3	Virginis
Vol,	Volans	8	-69	Volantis
Vul,	Vulpecula	20	25	Vulpeculae

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Thanks:

1) The members of the Saguaro Astronomy Club (pronounced sa-war-oh) of Phoenix. Who compiled the: SAC DEEP SKY DATABASE VERSION 8.1.. The original SAC, SAO or PPM files (not in HNSKY format) are available at www.saguaroastro.org/content/downloads.htm

2) Wolfgang Steinicke's for his monumental work, correcting the NGC &IC. http://www.klima-luft.de/steinicke/index_e.htm

3) Writers O. Montenbruck and T. Pfleger for their book and diskette "Astronomy on the Personal Computer" English edition 1998 (Almost equal to 1993 edition).

4) The Smithsonian Astrophysical Observatory for their SAO star catalog of 258997 stars.

5) U. Bastian and S. Roeser (Astronomisches Rechen-Institut, Heidelberg) who compiled the Catalogue of Positions and Proper Motions (PPM).

6) USNO for the UCAC4.

7) ESA for the Tycho and Gaia catalog.

8) The organizations and many people behind:
http://simbad.u-strasbg.fr
http://archive.eso.org/
http://skyview.gsfc.nasa.gov

9) And finally some more books which where very useful:

• The astronomical companion by Guy Ottewell. Very compact but full of (technical) information to understand, enjoyment, as a reference and as a none mathematical course in astronomy. Fourteenth printing 1995.
• Astronomical formulae for calculators by Jean Meeus. Edition 1988
• Astronomical algorithms by Jean Meeus. Edition 1991

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Jet Propulsion Laboratory Development Ephemeris.

Info:
Use in HNSKY: Menu SETTINGS, topic JPL DE
Info Wikipedia: https://en.wikipedia.org/wiki/Jet_Propulsion_Laboratory_Development_Ephemeris

Download:
Only required if you want the very best accuracy for occultations or want planetary positions outside the 1750-2250 range of the internal solution.

Move mouse to one of the links below and with right mouse button and select SAVE LINK AS... This will download the file. Only one file is sufficient. You place the file either in the program folder typically \Program files\hnsky or at the document folder Documents\hnsky Select the correct JPL_DE folder in HNSKY menu SETTINGS by double click on the path and browse to the file. It is working if the capital letters DE are shown in the (blue) title bar of HNSKY. If your outside the time range, the letters DE will disappear. The program will use then the default internal solution and give a warning message at the status bar.

DE430, range year 2000 up to 2050 ( 5 mbytes):
www.hnsky.org/lnxp2000p2050.430

DE430, range year 1550 up to 2650 (100 mbytes)
ftp://ssd.jpl.nasa.gov/pub/eph/planets/Linux/de430/linux_p1550p2650.430

DE431, range year -13000 up to +16999 (2800 mbytes!!)
ftp://ssd.jpl.nasa.gov/pub/eph/planets/Linux/de431/lnxm13000p17000.431

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Web page of HNSKY, CDS and others.

HNSKY or "Hallo northern sky" homepage. Here you can download the latest version of HNSKY: http://www.hnsky.org/software.htm

The ASCOM telescope driver: http://ascom-standards.org/

SAGUARO ASTRONOMY CLUB containing deep sky database SAC8.1: http://www.saguaroastro.org/

Centre de Données astronomiques de Strasbourg

Simbad astronomical database: http://simbad.u-strasbg.fr/simbad/

To download UCAC4 from internet (8.5 Gbytes): ftp://cdsarc.u-strasbg.fr/cats/I/322A/sc/

TDT-UT estimates: http://eclipse.gsfc.nasa.gov/SEhelp/deltaT.html

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