Tour: Young "Sun" Caught Blowing Bubbles by NASA's Chandra
(Credit: NASA/CXC/A. Hobart)
[Runtime: 03:27]

With closed-captions (at YouTube)

For the first time, astronomers have seen a bubble around a star that is similar in size and mass to our Sun, but much younger. This discovery, made using NASA’s Chandra X-ray Observatory, teaches astronomers about what might have been happening on our own Sun billions of years ago.

The discovery of this bubble, which astronomers called an “astrosphere,” was made around the star named HD 61005. This star is about 120 light-years from Earth.

Where does this astrosphere come from? Winds from the star’s surface are blowing up the bubble and filling it with hot gas as it expands into much cooler gas and dust surrounding the star. Our Sun has a similar bubble called the heliosphere. Scientists are interested not only how the heliosphere works today, but also how it behaved in the past.

The discovery of the astrosphere around HD 61005 gives them a window into our younger Sun. HD 61005 is only about 100 million years old, compared to the Sun’s age of about 5 billion years. Because it is so young, HD 61005 has winds of particles blowing from its surface that are about hundreds of times stronger than the wind from the Sun.

This is the first full view of an astrosphere that astronomers have obtained around a star like the Sun. For a few decades, astronomers have been trying to get an image of an astrosphere. Up until now, they were only able to capture images that were just a single point of light and didn’t give any information on the structure of the astrosphere itself.

Chandra was finally able to detect the astrosphere around HD 61005 because it is producing X-rays as the stellar wind runs into cooler dust and gas that surrounds the star. It required an X-ray telescope with the sharp vision of Chandra plus a long enough observation time to collect the data to make this discovery.

Previously, astronomers had nicknamed HC 61005 the “Moth” because the large amounts of dust in a disk around the star that you can see in infrared data, which gives it the appearance of the insect. This disk formed when rocks and icy bodies left behind after the star collided together, which is where the Kuiper Belt in our own solar system came from.

Because the strong wind should be blowing dust in the disk away from the star, the dust that makes up the moth-like structure around HD 61005 either does not last very long or is continually replenished by an unseen massive disk that keeps stirring itself to create more dust grains. This is something that astronomers will continue to investigate.

While you won’t be able to see all the things that Chandra and the other telescopes in space can, you can spot it with binoculars if you know where to look!

Quick Look: Young "Sun" Caught Blowing Bubbles by NASA's Chandra
(Credit: NASA/CXC/A. Hobart)
[Runtime: 00:46]

With narration (video above with voiceover)

With NASA’s Chandra, astronomers found the first “astrosphere” around a Sun-like star.

An astrosphere is a bubble of particles blown by winds from the star’s surface.

Our Sun has a similar bubble, but this star’s bubble is a few billion years younger.

This discovery reveals clues to how our Sun behaved when it was very young.