Are there any large star databases containing mass and density?

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Discussion Overview

The discussion centers around the search for large star databases that include detailed information such as mass and density, particularly focusing on databases that contain data for a significant number of stars (preferably over 50,000) and are based on nearby stars for accuracy. Participants explore the availability of such databases and the challenges in obtaining the desired data.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant expresses difficulty in finding large star databases that meet specific criteria, including mass and density, and suggests that such data may not exist or be readily available online.
  • Another participant recommends the Hipparcos database, noting it contains over 110,000 stars with precise parallax data but lacks mass information.
  • A participant acknowledges the Hipparcos database's advantages but reiterates the importance of mass data, mentioning their attempts to estimate mass using luminosity and spectral data, while expressing concerns about the uncertainty of this method.
  • One participant suggests that mass can be estimated from luminosity and spectral types using the mass-luminosity relation, although this may not provide precise values.
  • Another participant points out that accurate measurements of stellar mass and size are primarily possible for binary systems and references a limited stellar mass table by Belikov (1995) that contains only a few hundred entries.

Areas of Agreement / Disagreement

Participants generally agree on the challenges of finding comprehensive star databases with mass data, but multiple competing views exist regarding methods for estimating mass and the availability of relevant databases.

Contextual Notes

Participants highlight limitations in the availability of mass data and the challenges associated with estimating mass from other stellar properties, indicating that the discussion is constrained by the current state of star cataloging and measurement techniques.

Xilor
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Hi, I was trying to find large star databases to work with, but found that most of the databases I could find did not come close to what I was looking for. Is it possible the data I'm looking for just doesn't exist yet?
The data I'm looking for should preferably contain all kinds of stars and be mostly based on the closest stars since that data would probably be the most accurate and complete. But after searching for a while, all the databases I could find were too small (I was hoping for 50000+) or were missing variables that are important to me (mass, density, whether it is part of a binary/trinary system, spectral type, position, space velocity) and the 'would be nice' variables (age, total redshift, lifetime phase, error bars) or I couldn't actually download them.

I'm starting to suspect such databases don't exist or aren't placed online, possibly because mass and density might not be too easy to calculate. But I was hoping that someone here might be able to point me to databases I missed.
 
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Have you tried Hipparcos?
http://heasarc.gsfc.nasa.gov/W3Browse/star-catalog/hipparcos.html#crl_dec_ra

It's a large database of some +110 000 stars with very precise parallax data(you'll have to convert it to distance yourself).
It includes proper motion data, but no mass.
As far as I'm aware you'll have a hard time finding a catalogue with mass data, as this quantity is not easy to determine.
 
I haven't tried that, it does seem to have a lot more information than the one I was using. Which was the one downloadable here: http://www.astronexus.com/node/34
But without mass it doesn't really add what I'm looking for. I'm currently trying to find a way to use a combination of luminosity and spectral data to lump the stars in categories and to then try and estimate the mass of them based on those categories and the luminosity. But that would add so much uncertainty that it's probably not worth pursuing.
 
Depends on whether you need to be precise or not, you could guesstimate the masses from luminosity and spectral types via the mass-luminosity relation. I think.

edit: (which is what you've just said yourself, I've noticed)
 
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