Expert: Jayendra Upadhye - 8/4/2004

Question
I'm reading about the Milky Way, clusters etc and i came across the term Sag DIG. Can you please tell me what it is?  

Answer
Hi Matt,
Sag DIG is a gas-rich, blue dwarf irregular galaxy with some known recent star formation.
It is also known as "Sagittarius Dwarf Irregular Galaxy".
there is obviously "Sag DEG" Which would mean "Sagittarius Dwarf Elliptical Galaxy" and so on.
Somewhere on the web there is likely to be a Galaxy naming convention. Such as the I.U.P.A.C which has helped Industrial Organic chemists a lot! It certainly helped me to know about number of shared bonds between two carbon atoms just by knowing the name, whether it was ethene, or ethyne or ethane!
But I am not aware of such a highly standardised convention for galaxies.
Use link:-
http://seds.lpl.arizona.edu/messier/more/local.html it lists both Sag DEG and Sag DIG.

If you by chance are studying Organic chemistry or are interested, this link to the IUPAC will prove very interesting.
http://www.chem.qmul.ac.uk/iupac/

Jayen.