The size of Charon

In this week's edition of Nature, there is a report detailing observations of Pluto's moon Charon occulting a background star. The observations were made using part of the Very Large Telescope, the 0.5m Campo Catino Austral Telescope and the 2.5m Jorge Sahade telescope which are all based in South America.

At each of the three sites they saw the star passing behind a different part of Charon and this allowed accurate measurements of the diameter. The diameter is now found to be 603.6 km (±5.0km) which is incredibly accurate for a measurement of something so far away. Once you have a diameter for Charon you can also combine that with the mass of the moon to work out the average density. It turns out to be about 1.7 gm/cm³ which is equivalent to "an icy body with about slightly more than half of rocks". You can listen to this on the Nature podcast or read the ESO press release for more details.

Pluto is making the news quite a lot at the moment. It should get even more exciting soon as the first mission to Pluto should be launching in about 12 days time.

Tags: |
Posted in astro blog by Stuart on Thursday 05th Jan 2006 (08:51 UTC) | 3 Comments | Permalink

Comments: The size of Charon

what is the radius of Charon?

Posted by Stephanis Cheung on Wednesday 05th Apr 2006 (14:27 UTC)

Love your post and learn more about the thing I never known but interested.I also have a website about some acronyms ralated to many fields,including Astronomy.Please have a support and give some advices THANKS.

http://www.acronymlist.org/category/Astronomy-Acronyms.html

Posted by jessica on Monday 02nd Aug 2010 (01:52 UTC)

Love your post very much.And how many means do you know about 'NY',you may know the New York,anything else?! my web will give you answer.It will show you many many acronyms in some feilds,such as computers,chattings,economics, Astronomy and so on.Please give us your advices.

http://www.acronymlist.org/

Posted by jessica on Monday 02nd Aug 2010 (06:57 UTC)

ADD A COMMENT:


Don't provide an email/URL unless really necessary as your comment may get caught in the spam filter. No URLs get turned into links so don't bother. The ground rules for commenting are:
  1. No profanity or personal attacks please. Keep it clean.
  2. Restrict comments to subjects relevant to the post.
  3. Don't mention Pluto. If you do it'll be replaced by Goofy.
  4. No spam i.e. anything commercial unrelated to astronomy.
  5. If you think you've discovered a Theory of Everything, a replacement to Relativity, or something similar then please publish it in a journal rather than in my comments.
Comments against the spirit of these ground rules may be removed.











* required fields