Discovering the Sun's New Twin: HD 101364

[Astronuc]

I heard this the other day on a radio science program.

Astronomers have identified a yellow star they say is the best twin to our own sun yet seen. In other words, it's a star that's almost identical to the sun. And that's interesting because our sun shines on a life-bearing planet.

But stars like the sun are rare, according to astronomers. They account for only 4 percent of all stars in our Milky Way galaxy. And stars exactly like our sun must be even more rare. Scientists reported the previously best known example - a star named 18 Scorpii - ten years ago.

Now Jorge Melendez at Mount Stromlo Observatory in Australia and Ivan Ramirez at the University of Texas at Austin say they've found an even better solar twin. Its name is HD 101364. It is 220 light-years from Earth.

These astronomers say the star's mass, temperature, and chemical composition appear to match the sun's exactly. But the star may emit slightly more light than our sun. Since sun-like stars brighten as they age, this suggests the star may be a billion years older than our sun.

But that difference might actually be good news for extraterrestrial life seekers. It means an orbiting planet has had even more time to give rise to life than Earth has.

from http://www.Earth'sky.org/radioshows/51873/the-sun-has-a-twin


The star that is the sun's new twin - HD 101364 - also has the name HIP 56948.

http://arxiv.org/abs/0709.4290 - HIP 56948: A Solar Twin With a Low Lithium Abundance

http://kencroswell.com/HD98618.html

http://kencroswell.com/18scorpii.html

 

[Ironside]

Interesting article. However, if the sun is 1 billion years older than ours, that would suggest that if there is life on that solar system, it would be far superior to ours. So, how come they have not reached us yet. If we our sun is so identical, wouldn't they have picked up the similarities as well? Then again there could be life but maybe not nearly as advanced as us.

 

[neutrino]

Ah, it's not a longlost binary companion, then.

 

[Astronuc]

Interesting article. However, if the sun is 1 billion years older than ours, that would suggest that if there is life on that solar system, it would be far superior to ours. So, how come they have not reached us yet. If we our sun is so identical, wouldn't they have picked up the similarities as well? Then again there could be life but maybe not nearly as advanced as us.

I think the estimate on age is +/- 1 billion yrs. I think the sun and HD 101364 are more or less the same in size, class and luminosity, but that doesn't necessarily imply simliarity with respect to a planetary system. On the other hand, that is very interesting if the sun formed with a planetary system and HD 101364 did not.

 

[Ironside]

I think the estimate on age is +/- 1 billion yrs. I think the sun and HD 101364 are more or less the same in size, class and luminosity, but that doesn't necessarily imply simliarity with respect to a planetary system. On the other hand, that is very interesting if the sun formed with a planetary system and HD 101364 did not.

True, there are a lot of factors to be considered, really all humanity can do is wait to advance in technology good enough to take us to other solar systems. For now we can only guess.

 

[nrqed]

I think the estimate on age is +/- 1 billion yrs. I think the sun and HD 101364 are more or less the same in size, class and luminosity, but that doesn't necessarily imply simliarity with respect to a planetary system. On the other hand, that is very interesting if the sun formed with a planetary system and HD 101364 did not.

It's very true that an important factor is the probability that a sun similar to ours has planets orbiting it (isn't it one of the factors in the Drake equation?). And then there is the probability that a planet would be in the habitable range of possible orbits...and then that life would have formed and so on.

But still, I find that the most exciting aspect is that a star so similar to ours has been found so darn close! I bet people will aim telescopes at it and listen in the water hole region of the spectrum.

Assuming that there are "people" there and that they would not be aiming any directed signals at us but that they have been broadcasting for more than 220 years, I assume that our technology is not advanced enough to monitor such stray signals from such a distance?