A 13.2Billion year old star just 186 Lyrs from earth

  • Context: Undergrad 
  • Thread starter Thread starter Tanelorn
  • Start date Start date
  • Tags Tags
    Earth Star Year
Click For Summary

Discussion Overview

The discussion revolves around the discovery of a 13.2 billion-year-old star located 186 light-years from Earth, exploring its implications regarding stellar populations, redshift, and the potential for intelligent life around older stars. The conversation includes theoretical considerations and clarifications about stellar classifications and lifespans.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants express surprise that very old stars can be observed at relatively low redshifts, suggesting a misunderstanding of stellar lifespans and redshift relationships.
  • One participant notes that the star in question is not a Population III star due to its measured metallicity, indicating it belongs to a different classification.
  • Another participant explains that Population III stars are expected to be short-lived, and thus it is not surprising that older stars can be found nearby, as their age is not directly tied to redshift.
  • A clarification is made regarding the definitions of star population classes, with a specific mention that HD 140283 is classified as a Population II star.
  • One participant proposes that the high velocity of HD 140283 could suggest it was ejected from a nearby low metallicity dwarf galaxy.

Areas of Agreement / Disagreement

Participants exhibit a mix of agreement and disagreement, particularly regarding the implications of stellar age and classification. There is no consensus on the broader implications of the star's age for the development of intelligent life.

Contextual Notes

Some limitations include the dependence on definitions of stellar populations and unresolved questions about the implications of stellar age on the potential for life.

Tanelorn
Messages
906
Reaction score
15
A 13.2Billion year old star just 186 Lyrs from earth

I thought that these really old stars would have only been observed at super high red shifts because of a shorter life but apparently not.

http://www.salon.com/2013/01/12/astronomers_may_have_found_the_oldest_star_in_the_universe/


After thought: Would older stars have a greater chance of developing intelligent life?
 
Space news on Phys.org
Tanelorn said:
I thought that these really old stars would have only been observed at super high red shifts because of a shorter life but apparently not.
The article mentions explicitly that this is not a population III star, due to the measured abundance of metals.
 
Population III stars are expected to be very short lived, so its not big surprise we haven't seen any. The age of a star has little to do with redshift. Stars at high redshift are limited in age to that of the universe at that age, so a star with a redshift of 2 could not be more than about 3 billion years of age given the universe itself was only about 3.3 billion years old when those photons left that star. Hence, it is unsurprising some of the oldest stars in the universe are relatively nearby. A low mass star like a red dwarf is capable of 'living' much longer than the age of the universe. A star like the sun has a main sequence life expectancy of around 9 billion years.
 
Just to clarify, I did not know the definitions of the various star population classes. My recollection was that the first stars were very short lived hence my surprise to find that one as old as this still existed in our own back yard. I think this article says that this old star HD 140283, is a population II star.
 
Given its relatively high velocity, HD 140283 could be a star ejected by a nearby low metallicity dwarf galaxy.
 

Similar threads

  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 19 ·
Replies
19
Views
4K
  • · Replies 9 ·
Replies
9
Views
4K
  • · Replies 3 ·
Replies
3
Views
6K
  • · Replies 20 ·
Replies
20
Views
4K
  • · Replies 23 ·
Replies
23
Views
5K
  • · Replies 13 ·
Replies
13
Views
7K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
7K
  • · Replies 4 ·
Replies
4
Views
3K