The sun has a twin: the star HD 101364

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 Meléndez at Mount Stromlo Observatory in Australia and Iván Ramírez at the University of Texas at Austin say they’ve found an even better solar twin. Its name is HD 101364. It’s 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.

Our thanks to:
Jorge Meléndez
Mt. Stromlo in Australia