Celestia Forums

Dear Seddon Thanks for your response. <<The ESA Tycho catalog does not include any distances or parallax values.>> I thought it did though. Most sources seem to imply it does - can you explain what's happened there then. See: http://apm5.ast.cam.ac.uk/hipp/tycho.html or http://adc.gsfc.nasa.gov/adc-...

Hi

Can anyone point me to where I can download the Tycho 1997 catalogue already in Excel format?
Looking for all stars up to around 40 light years away.

Thanks

Thanks Fridger, very helpful. However........errrm.....................slight error in orders of magnitude......... Have now spoken to the original author again. The max distance for measurement of star density around the sun was 38 light years - not 35 million (told you it was only a slight error.....

OK thanks.
But if the results show a star depletion over 360 degrees in all planes (as I believe his work indicated), it would indicate either that there is something unusual going on, or there is an inherent problem with the way we estimate star distances, would it not?

<<So ideally one needs to first examine a display of the acceptance across the full angular region.>>

Sorry, not sure what that means...or how to go about doing it?

A scientist colleague of mine once did a manual 3D calculation (using I think the Hipparcos and Tycho catalogues) and claims that the results gave a low star density for so many light years around the sun - compared to average density throughout the "sphere". ie the conclusion would be tha...

Thanks for that.
OK if we started with just the 100,000 (or even the 2,000,000) stars, how might we approach the display side?
I know a good programmer. Is there a resource that explains how to go about it?
Thanks again.

Hi I would like to go out to say 50 million light years and look back on the sun and all the stars surrounding the sun in a 35 million light year diameter sphere. So you would see a ball of stars with the sun in the middle and then take sections through the centre to look at the relative star densit...