I've tried utilizing "Google Sky", however, once I've found the location of said star and am in the process of zooming in, the site craps out. Anyway... if there's someone out there with a little more experience in this field, here are the coordinates of the star i'm searching for: 10h 10m 11.1s, +4 3' 12.3"

I'd appreciate the effort, and thank's in advance.

  • 1
    $\begingroup$ Do you happen to know what epoch your coordinates are stated in? Is it J2000? $\endgroup$
    – zephyr
    Commented Oct 7, 2016 at 13:07

2 Answers 2


As far as I can see, this is just a faint star. Here is some data from the USNO B1.0 catalogue:

USNO B1.0 star

B1.0 ID: 0940-0181715

RA: 10h10m11.13s +/- 69 milliarcseconds

declination: + 4 03' 12.3" +/- 195 milliarcseconds

Epoch: 1977.9

Proper motion in RA: 12 +/- 2 milliarcseconds/year

Proper motion in dec: 6 +/- 6 milliarcseconds/year


Band mag Cal Survey Emulsi field S/G xi eta

B1: 14.36 1 POSS-I 103a-O 550 4 -0.05 0.03

R1: 13.33 1 POSS-I 103a-E 550 1 0.05 0.01

B2: 14.07 2 POSS-II IIIa-J 782 9 0.09 0.26

R2: 12.79 2 POSS-II IIIa-F 782 8 -0.07 -0.02

I: 12.37 2 POSS-II IV-N 781 -0.04 -0.30

"Cal" = calibration: 0 means calibrated via bright standard stars on the plate; 1 = via faint standards on the plate; 2 = faint standards on adjacent plate; 3 = faint standards two plates away, etc. "S/G" = star/galaxy index. 11=object looked starlike, to 0=fuzzy/galaxy-like. xi, eta = displacement of the star's position on this plate, in arcseconds, relative to the mean solution.

This USNO-B1.0 data was downloaded from a VizieR server.

  • $\begingroup$ Do you have a name for this star? And how do you know the epoch in reference is 1977.9? $\endgroup$
    – zephyr
    Commented Oct 7, 2016 at 13:04
  • $\begingroup$ I don't think it has a name - it's quite faint. The epoch is just what came from my planetarium software. I suspect the date quoted relates to when the measurement was made. The software was probably assuming the coordinates were JD 2000. $\endgroup$
    – Dr Chuck
    Commented Oct 8, 2016 at 17:44

Up to my understanding these are 2 angles, One is vertical one(Where parallel to ground is zero, perpendicular towards sky is 90) and One is horizontal one (Compass, where north will be considered as zero/360).

10h 10m 11.1s, +4 3' 12.3"(Vertical, Horizontal)

First one , 10h 10m 11.1s. It's hour min sec format. Where 1 hour is 360(total degrees)/24(number of hours in a day)=15 degrees. for 1 minute, 15(degrees per hour)/60 (no of minutes in an hour). same for the second. So that this angle will come around ~150+2.5+ (second's part).

second one, +4 3' 12.3". This one is degree min sec. Most probably this is compass angle. where north might be zero and clockwise is +ve. representation may vary, but if you'll check the scale you'll be able to figure out that.

Hope this will help you.if not feel free to ask more.

  • 2
    $\begingroup$ The co-ordinates are right ascension and declination. $\endgroup$
    – Dr Chuck
    Commented Oct 7, 2016 at 7:29
  • $\begingroup$ This answer describes horizontal coordinates. Star positions are usually given in equatorial coordinates. $\endgroup$
    – Mike G
    Commented Oct 7, 2016 at 15:24

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .