Accuracy of NGC coordinates

[Stevo69]

I have two questions relating to RA and DEC coordinates from a catalogue or book, and using this data on a computer-controlled scope, such as the GOTO-type systems on the market.

I notice that some books and online lists show RA and DEC (2000.0) coordinates in hours, minutes AND seconds. While other sources do not show seconds. With GOTO/computer-controlled systems, is just hours, minutes and decimal seconds accurate enough for locating objects?

I guess it could depend on the faintness? I have lots of lists with just RA: hh mm.s, DEC: dd, mm

I'm just thinking ahead as I plan to purchase a Celestron CGT XLT 11" down the track.

Hoo roo.

[astroron (Ron)]

I think the program in the GOTO should update itself and so should be accurate enough to find any object in say a 30mm eyepiece which in an f10 SCT gives you about 45 arcminutes field of view, if it is visible.

[gary]

Originally Posted by Stevo69

I notice that some books and online lists show RA and DEC (2000.0) coordinates in hours, minutes AND seconds. While other sources do not show seconds. With GOTO/computer-controlled systems, is just hours, minutes and decimal seconds accurate enough for locating objects?

I guess it could depend on the faintness? I have lots of lists with just RA: hh mm.s, DEC: dd, mm

A pointing system that accepts RA as hh mm ss or hh mm.m and Dec as dd mm
will tend to provide enough precision for amateur scopes for all practical purposes.

Best Regards

Gary Kopff
Mt. Kuring-Gai