nearby white dwarfs

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Jim</i>
<br />This should prove weather or not the WD is older than the star it orbits as well as a few other points.<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Sounds like a good research project. Why not try it? -|Tom|-

I have been trying but who has the data? I don't have any access to the equipment needed to amass data on WD objects. Anyway, if they are in fact radiating anywhere near what a blackbody would radiate they should have a wide range of temperateres now since WDs have been made throughout time. But, I don't find any data indicating what individual WDs temperatures are. Have they ever been measured by astronomers?

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Jim</i>
<br />I have been trying but who has the data? ... I don't find any data indicating what individual WDs temperatures are. Have they ever been measured by astronomers?<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Finding the data and learning how to use it are part of any research project. Search the web, the literature, and the data centers. The Astrophysics Data System at http://adswww .harvard.edu is a good place to start. (Remove blank in middle to reassemble correct link. This MB won't parse it properly.) -|Tom|-

I sent an e-mail request to the data center but what can be done if the data has never been amassed? The source of data like this would be very large telescopes with a spectra measuring appliance. Not too many of them around I don't suppose so who manages those that do exist? Maybe some new data can be obtained if its requested.

<blockquote id="quote"><font size="2" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Jim</i>
<br />I sent an e-mail request to the data center but what can be done if the data has never been amassed? The source of data like this would be very large telescopes with a spectra measuring appliance. Not too many of them around I don't suppose so who manages those that do exist? Maybe some new data can be obtained if its requested.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">Tha ADS is a self-serve database. I'll be surprised if they have a person assigned to answer questions by email.

The system should enable you to find who has such data or is studying such issues. No one is going to collect data for you unless you pay for the telescope and personnel time with a large grant. -|Tom|-

The data is not to be found at this time but the H-R diagram indicates WD objects do vary in temperature and I have learned WDs also vary in mass. The thing that is very murky is weather or not these properties indicate age. It seems to me all WDs start out the same way so the variation in mass and temperature should be an indicator of age. But, how can this be pinned down one way or the other? In working on the rate of cooling it seems likely the oldest WD objects might be very old.