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Dinosaur star
Galaxy Babe - eclectic editor Started conversation Jul 13, 2003
Some 13 billion years ago in a distant cluster of stars, a planet
formed.
Remarkably it's still there, according to astronomers using the Hubble
Space Telescope.
How do they know it's still there?
When we're looking into outer space, aren't we looking backwards in time? It could have disintergrated long ago....and we could be looking at its 
Dinosaur star
Tabitca Posted Jul 13, 2003
one for the philosophers I think ! How are you ? Hope things are going ok
Dinosaur star
pheloxi | is it time to wear a hat? | Posted Jul 13, 2003
Galaxy Babe going back into past while living in the future
Dinosaur star
pheloxi | is it time to wear a hat? | Posted Jul 13, 2003
oh yeah do not change too much in past, because we might suddendly have green ears!
Dinosaur star
Clelba Posted Jul 15, 2003
what's wrong with green ears?
^. .^
= ' =
Guru
CommunityArtist
Dinosaur star
turvy (Fetch me my trousers Geoffrey...) Posted Jul 15, 2003
Hi Galaxy Babe
Is this the planet located in M4 and posted on the NASA web site?
(Here as it happens. http://www.nasa.gov/home/hqnews/2003/jul/HQ_03234_Oldest_Planet.html or http://hubblesite.org/newscenter/archive/2003/19/ which has more images. )
If it is then the light is only 5600 years old. I suppose it is conceivable that the planet has evapourated or something, but after 13 billion years and a supernova it is doing quite well!
turvy
Dinosaur star
turvy (Fetch me my trousers Geoffrey...) Posted Jul 16, 2003
Probably a slightly fishy smell and wrinkles!
Dinosaur star
turvy (Fetch me my trousers Geoffrey...) Posted Jul 23, 2003
You have obviously never looked after old people!!
turvy
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Researcher 159112 Posted Jul 23, 2003
isn't it something to do with time + space and light? Telling how old it is, I mean...?
Dinosaur star
turvy (Fetch me my trousers Geoffrey...) Posted Jul 23, 2003
The simple answer is yes!
After that it gets harder to explain but stick with it...
1. Light (electromagnetic radiation) travels at approx. 300,000 kilometres per second. This is an absolute under normal conditions in this universe. Nothing can travel any faster and light goes no slower. A light year is the distance that light travels in 1 terrestrial year, so a light year is a distance measure that is also an expression of time. If something is 5600 light years away it is within our Galaxy, which is big, but the light from it takes 5600 years to reach us here on Earth
2. The age of the planet and the star cluster it lives in is a different matter. This is measured in a number of ways and relies on the acceptance of the validity of a number of measures, the main one being the Hubble constant - the rate of expansion of space. Others include the type of stars found in the cluster which are assessed by studying their colour/temperature and the presence or absence of certain elements in their makeup (I don't mean mascara and lippy here!) and how far away they are. Distance is estimated by looking for what are called 'standard candles' - Cepheid variable stars which vary in brightness very specifically with a direct correlation to redshift. Combine this with the Hubble constant and you have distance (a best guess anyway)
Globular clusters are generally full of smallish, oldish stars which formed early in the life of the Galaxy between 13 and 20 billion years ago (if you accept the Hubble constant as true). Hence the estimated age of the planet in question. This best guess is done by people who are a lot smarter that me so I tend to accept what they say.
there is still debate about the age of the Universe. Apparently there are stars in our Galaxy that are older than the best fit age of the Universe. 
Hope you are still here?
turvy
Dinosaur star
Researcher 159112 Posted Jul 24, 2003
I read A Brief History of Time, but it's a bit difficult. Not to understand, just to imagine things that are bigger than my existance... does that sound silly?
Dinosaur star
turvy (Fetch me my trousers Geoffrey...) Posted Jul 25, 2003
No it's not silly at all.
When I read it I was filled with a sense of wonder and a need to discover more. It's just a sideline for me really - something I enjoy reading about along with Sci Fi and Harry Potter at the moment. I've just read 3 books by Alistair Reynolds (Revelation Space, Chasm City and Redemption Ark). Outstanding!
There are lots of books out there that help you to get to grips with the Cosmology. Sir Martin Rees, the Astronomer Royal has written some good stuff as has John Gribben.
turvy
Dinosaur star
Galaxy Babe - eclectic editor Posted Jul 25, 2003
"Apparently there are stars in our Galaxy that are older than the best fit age of the Universe"
I'm reminded of the chicken and the egg question.........but 
s are really pretty to gaze at........and who cares how old they are?
Dinosaur star
pheloxi | is it time to wear a hat? | Posted Jul 25, 2003
bit by bit the egg gets legs
an african saying
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Dinosaur star
- 1: Galaxy Babe - eclectic editor (Jul 13, 2003)
- 2: Tabitca (Jul 13, 2003)
- 3: pheloxi | is it time to wear a hat? | (Jul 13, 2003)
- 4: pheloxi | is it time to wear a hat? | (Jul 13, 2003)
- 5: tom (Jul 13, 2003)
- 6: Clelba (Jul 15, 2003)
- 7: pheloxi | is it time to wear a hat? | (Jul 15, 2003)
- 8: turvy (Fetch me my trousers Geoffrey...) (Jul 15, 2003)
- 9: Sergeant Mushroom (Jul 15, 2003)
- 10: turvy (Fetch me my trousers Geoffrey...) (Jul 16, 2003)
- 11: Clelba (Jul 22, 2003)
- 12: turvy (Fetch me my trousers Geoffrey...) (Jul 23, 2003)
- 13: Researcher 159112 (Jul 23, 2003)
- 14: turvy (Fetch me my trousers Geoffrey...) (Jul 23, 2003)
- 15: Researcher 159112 (Jul 24, 2003)
- 16: turvy (Fetch me my trousers Geoffrey...) (Jul 24, 2003)
- 17: Researcher 159112 (Jul 24, 2003)
- 18: turvy (Fetch me my trousers Geoffrey...) (Jul 25, 2003)
- 19: Galaxy Babe - eclectic editor (Jul 25, 2003)
- 20: pheloxi | is it time to wear a hat? | (Jul 25, 2003)
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