Horologium
the Clock
Star chart
J2000the Clock
Fixed J2000 coordinates
This image was made with reference to IAU charts.View IAU original · Opens in a new tab
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How to read this chart
Dots mark stars, and their sizes indicate brightness. Stars appear dark on light charts and light on dark charts. Green lines show a constellation pattern. The surrounding grid gives right ascension and declination.
This is a fixed reference map, rather than a view of tonight’s sky.
Read the full chart guide →Boundary coordinates
The boundary marks a sky region; it is separate from the green star pattern. These files preserve ordered coordinate points in the J2000 reference system.
Horologium23 boundary pointsDownload TXT →
View coordinate format & sample
Right ascension uses hours, minutes and seconds. Declination is in degrees. Convert right ascension to degrees with 15 × (hours + minutes/60 + seconds/3600).
RA (h m s) | Dec (degrees) | Abbreviation 04 20 18.3390 | -39.7007294 | HOR 04 19 31.7727 | -48.6996651 | HOR 04 08 35.9779 | -48.6699715 | HOR 04 08 23.6735 | -50.6697006 | HOR 03 53 30.5199 | -50.6304779 | HOR
The 0h / 24h meridian is continuous. A coordinate jump there should not be treated as a straight line across a flat map.