Sunday 3 April 2022

When the star 32 Cam is not 32 Cam


If you check star atlas 2000 (1998) and look at the star marked 32 Cam at position RA 12h 49 min 13.7 sec and Dec +83 degrees 24 mins 46 secs you will be in for an interesting adventure. Why? Well although labelled 32 Cam it is in fact the star Struve 1694. Before you suggest that it is another name for 32 Cam you are wrong. The star Struve 1694 was originally part of the constellation of Camelopardalis the Giraffe under the designation 32H.It was the 32nd star in Camelopardalis which was labelled by the Polish astronomer Johannes Hevelius in his catalogue. It’s not 32 Cam.

If you check Norton’s star atlas you will see that this star is correctly labelled Struve 1694.

So what’s going on?

If you want to find out where 32 Cam can be found you will need to look at Xi Auriga, RA 05 h 54 m 50s + 55 deg 42 min 25 sec because this star was once part of Flamsteed’s constellation of Camelopardalis as 32Cam.

I don’t know where Sky atlas 2000 got there information from, but I have checked an old Norton’s Star Charts which was published in 1938 and the 2000 version which shows the star as Struve 1694,. Other star atlases have different ideas, the Cambridge Star Atlas (1996) by Wil Tirion shows it just as a double star but with no designation. The Atlas of the Night Sky by Storm Dunlop (2005) shows it as 32, while the stars by Dorling Kindersley (2016) show it as Struve 1694. I am sure there are other star charts available!

I don’t know at what point the star changed its designation, but I might guess that it was in 1930 when the International Astronomical Union defined the constellation boundaries and designations we use today.

As an aside around about the year 800CE Struve 1694 was the closest star to the north pole.

This is the only trouble when I undertake searches for high latitude novae and I find other things that make me change direction!!

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