Oldest star HD 140283

The star HD 140283 lies 190 light-years away from the Sun.
It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend 13.77 +/- s billion years ago.

Statistically, what is the probability that HD 140283 is older than the BB?

Dear lut...:

On Sunday, January 20, 2013 2:42:57 AM UTC-7, wrote:
....
The star HD 140283 lies 190 light-years away
from the Sun.

It is 13.9 +/- .7 billion years old,

Based on what assumptions? How much does a star age, if its heat sink temperature is hotter than our Sun's corona?

whereas the Big Bang happenend 13.77 +/- s
billion years ago.

Statistically, what is the probability that
HD 140283 is older than the BB?

Non zero.

David A. Smith

wrote:
The star HD 140283 lies 190 light-years away from the Sun.
It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend
13.77 +/- s billion years ago.

Where do you get your numbers for the star's age? This looks like a
misquote.

According to the 2013 AAS abstract by Howard Bond et al

http://adsabs.harvard.edu/abs/2013AAS...22144308B

the age and its formal error due only to parallax uncertainty is 13.30 ±
0.30 Gyr. They say there are larger uncertainties from stellar parameters
and chemical composition that are larger than 0.30 Gyr, though the abstract
does not quote what these add up to, though they say "considerably larger".


Statistically, what is the probability that HD 140283 is older than
the BB?

The error boundaries may overlap the age of the BB but no one thinks the
star is possibly older than the BB.

--
Mike Dworetsky

(Remove pants sp*mbl*ck to reply)

Le dimanche 20 janvier 2013 17:54:26 UTC+1, Mike Dworetsky a écrit*:
wrote:

The star HD 140283 lies 190 light-years away from the Sun.

It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend

13.77 +/- s billion years ago.



Where do you get your numbers for the star's age? This looks like a

misquote.



According to the 2013 AAS abstract by Howard Bond et al



http://adsabs.harvard.edu/abs/2013AAS...22144308B



the age and its formal error due only to parallax uncertainty is 13.30 ±

0.30 Gyr. They say there are larger uncertainties from stellar parameters

and chemical composition that are larger than 0.30 Gyr, though the abstract

does not quote what these add up to, though they say "considerably larger".





Statistically, what is the probability that HD 140283 is older than

the BB?



The error boundaries may overlap the age of the BB but no one thinks the

star is possibly older than the BB.

Mike Dworetsky

Thank you.

I read in the abstract that

"Within the errors, the age of HD 140283 is slightly less than the age of the Universe, 13.76 ± 0.11 Gyr, based on the microwave background and Hubble constant."

The BB happened 13.77 +/- 0.059 Gyr ago.

But our Galaxy must be older than HD 140283, thus older than the BB!

Dear lut...:

On Sunday, January 20, 2013 11:20:18 AM UTC-7, wrote:
....
But our Galaxy must be older than HD 140283,

So you do not believe that this star might not have predated the formation of this galaxy, and was simply a capture? Why?

David A. Smith

On 20/01/2013 11:54 AM, Mike Dworetsky wrote:
wrote:
The star HD 140283 lies 190 light-years away from the Sun.
It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend
13.77 +/- s billion years ago.

Where do you get your numbers for the star's age? This looks like a
misquote.

I think this might be where he got it from:

"The team then exploited the fact that HD 140283 is in a phase of its
life cycle in which it is exhausting the hydrogen at its core. In this
phase, the star's slowly dimming luminosity is a highly sensitive
indicator of its age, says Bond. His team calculates that the star is
13.9 billion years old, give or take 700 million years. Taking into
account that experimental error, the age does not conflict with the age
of the Universe, 13.77 billion years."

Nearby star is almost as old as the Universe : Nature News & Comment
http://www.nature.com/news/nearby-st...iverse-1.12196

Statistically, what is the probability that HD 140283 is older than
the BB?

The error boundaries may overlap the age of the BB but no one thinks the
star is possibly older than the BB.

Yes.

Yousuf Khan

On 20/01/2013 4:42 AM, wrote:
The star HD 140283 lies 190 light-years away from the Sun.
It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend 13.77 +/- s billion years ago.

Statistically, what is the probability that HD 140283 is older than the BB?

Statistically, you can ignore the numbers older than the BB. That's why
the error bars are so large.

It's kinda like statistics which estimate the population of some town to
be 500 +/- 600. There is no such thing as -100 people, so really the
population could be between 0 and 1100 people. You can safely ignore the
nonsense part of the error bars, just so long as some part of the error
bars existing within the sensical regions.

Yousuf Khan

wrote:
Le dimanche 20 janvier 2013 17:54:26 UTC+1, Mike Dworetsky a écrit :
wrote:

The star HD 140283 lies 190 light-years away from the Sun.

It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend

13.77 +/- s billion years ago.



Where do you get your numbers for the star's age? This looks like a

misquote.



According to the 2013 AAS abstract by Howard Bond et al



http://adsabs.harvard.edu/abs/2013AAS...22144308B



the age and its formal error due only to parallax uncertainty is
13.30 ±

0.30 Gyr. They say there are larger uncertainties from stellar
parameters

and chemical composition that are larger than 0.30 Gyr, though the
abstract

does not quote what these add up to, though they say "considerably
larger".





Statistically, what is the probability that HD 140283 is older than

the BB?



The error boundaries may overlap the age of the BB but no one thinks
the

star is possibly older than the BB.

Mike Dworetsky

Thank you.

I read in the abstract that

"Within the errors, the age of HD 140283 is slightly less than the
age of the Universe, 13.76 ± 0.11 Gyr, based on the microwave
background and Hubble constant."

The BB happened 13.77 +/- 0.059 Gyr ago.

Not sure why your figure differs from Bond et al.


But our Galaxy must be older than HD 140283, thus older than the BB!

Oh no, that isn't necessarily true at all! Our galaxy was (and is still
being) formed from many mergers of smaller galaxies over a long period of
time. In the Hubble Deep Fields all you see for very early epochs are small
irregular objects, few if any spiral galaxies at the earlier stages.
HD140283 could have come from the very early stages of star formation in one
such fragment, and that could have merged into the forming Galaxy at any
time.

--
Mike Dworetsky

(Remove pants sp*mbl*ck to reply)

Yousuf Khan wrote:
On 20/01/2013 11:54 AM, Mike Dworetsky wrote:
wrote:
The star HD 140283 lies 190 light-years away from the Sun.
It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend
13.77 +/- s billion years ago.

Where do you get your numbers for the star's age? This looks like a
misquote.

I think this might be where he got it from:

"The team then exploited the fact that HD 140283 is in a phase of its
life cycle in which it is exhausting the hydrogen at its core. In this
phase, the star's slowly dimming luminosity is a highly sensitive
indicator of its age, says Bond. His team calculates that the star is
13.9 billion years old, give or take 700 million years. Taking into
account that experimental error, the age does not conflict with the
age of the Universe, 13.77 billion years."

Nearby star is almost as old as the Universe : Nature News & Comment
http://www.nature.com/news/nearby-st...iverse-1.12196

Statistically, what is the probability that HD 140283 is older than
the BB?

The error boundaries may overlap the age of the BB but no one thinks
the star is possibly older than the BB.

Yes.

Yousuf Khan

OK thanks, the Nature article apparently has more information in it than the
published abstract of the talk.

--
Mike Dworetsky

(Remove pants sp*mbl*ck to reply)

Le lundi 21 janvier 2013 09:26:40 UTC+1, Mike Dworetsky a écrit*:
wrote:

Le dimanche 20 janvier 2013 17:54:26 UTC+1, Mike Dworetsky a écrit :

wrote:



The star HD 140283 lies 190 light-years away from the Sun.



It is 13.9 +/- .7 billion years old, whereas the Big Bang happenend



13.77 +/- s billion years ago.







Where do you get your numbers for the star's age? This looks like a



misquote.







According to the 2013 AAS abstract by Howard Bond et al







http://adsabs.harvard.edu/abs/2013AAS...22144308B







the age and its formal error due only to parallax uncertainty is

13.30 ±



0.30 Gyr. They say there are larger uncertainties from stellar

parameters



and chemical composition that are larger than 0.30 Gyr, though the

abstract



does not quote what these add up to, though they say "considerably

larger".











Statistically, what is the probability that HD 140283 is older than



the BB?







The error boundaries may overlap the age of the BB but no one thinks

the



star is possibly older than the BB.



Mike Dworetsky



Thank you.



I read in the abstract that



"Within the errors, the age of HD 140283 is slightly less than the

age of the Universe, 13.76 ± 0.11 Gyr, based on the microwave

background and Hubble constant."



The BB happened 13.77 +/- 0.059 Gyr ago.



Not sure why your figure differs from Bond et al.





But our Galaxy must be older than HD 140283, thus older than the BB!



Oh no, that isn't necessarily true at all! Our galaxy was (and is still

being) formed from many mergers of smaller galaxies over a long period of

time. In the Hubble Deep Fields all you see for very early epochs are small

irregular objects, few if any spiral galaxies at the earlier stages.

HD140283 could have come from the very early stages of star formation in one

such fragment, and that could have merged into the forming Galaxy at any

time.

Not so long ago, many people thougt that our Earth was alone in the Universe.
Now, it is presumed that billions of Earth-like planets are present in our galaxy.
Why wouldn't very many HD140283-like stars exist in our galaxy?
And why wouldn't some of them be still older than HD140283?





--

Mike Dworetsky



(Remove pants sp*mbl*ck to reply)