coordinates
coordinates
Hmmm..... just like to know, does any one know how get the exact right ascension and declination of a new object in the sky.
-
- Posts: 293
- Joined: Sun Oct 05, 2003 6:54 pm
Not sure what you are asking here.....
If you are asking how to use your setting circles to get the coordinates of a new object, you have to do a proper polar alignment. Your Dec should be set after this. Then point your telescope at an object whose coordinates you know. Then twist your RA circle until the readouts match those given in the charts. Then very quickly, point your telescope at your new object. Read off the setting circles and you have it.
If you are asking how to use your setting circles to get the coordinates of a new object, you have to do a proper polar alignment. Your Dec should be set after this. Then point your telescope at an object whose coordinates you know. Then twist your RA circle until the readouts match those given in the charts. Then very quickly, point your telescope at your new object. Read off the setting circles and you have it.
- Airconvent
- Super Moderator
- Posts: 5787
- Joined: Tue Sep 30, 2003 11:49 pm
- Location: United Federation of the Planets
I think what he means is how he can identify objects in the sky by looking at it. Checking the RA and declination would be one way but you will need some background knowledge on the more common constellations.
The easier way, of course is to use a goto computer (preferabbly with GPS!).
Point your scope to it and read the info off your autostar/hand controller!
rich
The easier way, of course is to use a goto computer (preferabbly with GPS!).
Point your scope to it and read the info off your autostar/hand controller!
rich
The Boldly Go Where No Meade Has Gone Before
Captain, RSS Enterprise NCC1701R
United Federation of the Planets
Captain, RSS Enterprise NCC1701R
United Federation of the Planets
- weixing
- Super Moderator
- Posts: 4708
- Joined: Wed Oct 01, 2003 12:22 am
- Favourite scope: Vixen R200SS & Celestron 6" F5 Achro Refractor
- Location: (Tampines) Earth of Solar System in Orion Arm of Milky Way Galaxy in Local Group Galaxies Cluster
Hi,
Below is what the information that I find on the web (thinking of doing a astronomy project for pocket pc, but no time... ) and I think it should be correct, but I have no time to verified:
Hour angle
-------------
HA =LST - RA (LST->Local Sidereal Time)
If HA negative, then add 360 to bring in range 0 to 360
RA must be in degrees.
Altitude
--------
sin(ALT) = sin(DEC) * sin(LAT) + cos(DEC) * cos(LAT) * cos(HA)
ALT = asin(ALT)
Aziumuth
-----------
cos(A) = sin(DEC) - sin(ALT)*sin(LAT) / cos(ALT)*cos(LAT)
A = acos(A)
If sin(HA) is negative, then AZ = A, otherwise
AZ =360 - A
Have a nice day.
Below is what the information that I find on the web (thinking of doing a astronomy project for pocket pc, but no time... ) and I think it should be correct, but I have no time to verified:
Hour angle
-------------
HA =LST - RA (LST->Local Sidereal Time)
If HA negative, then add 360 to bring in range 0 to 360
RA must be in degrees.
Altitude
--------
sin(ALT) = sin(DEC) * sin(LAT) + cos(DEC) * cos(LAT) * cos(HA)
ALT = asin(ALT)
Aziumuth
-----------
cos(A) = sin(DEC) - sin(ALT)*sin(LAT) / cos(ALT)*cos(LAT)
A = acos(A)
If sin(HA) is negative, then AZ = A, otherwise
AZ =360 - A
Have a nice day.
Yang Weixing
"The universe is composed mainly of hydrogen and ignorance."
"The universe is composed mainly of hydrogen and ignorance."