Gaia indices

[Karsten Schindler]

Having read a number of posts, I found some ambiguous information regarding available Gaia indices. 

So far, I thought the 5000 series was based on Gaia DR2 positions, and the 5200 series on Gaia EDR3. Thus, I expected both indices to be at Gaia magnitudes ("complete" between 12 and 17 mag), i.e. all bright stars missing, which can be problematic for the solver as it relies on the brightest stars in each quad.

This post mentions that for "the 5200-series, [Dustin] merged Tycho-2 and Gaia (carefully) to create a more complete input catalog before hpsplit and indexing."

I found no other explicit information if the 5200 series has actually merged Tycho2 and Gaia EDR3. If that holds true, it would probably be the "goto-index" for solving image data at visible wavelengths?

Thanks for confirming.

Karsten

[Dustin Lang]

Hi Karsten,

According to

http://data.astrometry.net/

the 5200-series is made from Tycho-2 + Gaia DR2.

The 5200-series is what the nova.astrometry.net service is using currently.

cheers,

dustin

[Karsten Schindler]

Thanks Dustin, I missed that page!