Interesting Astronomy & Astrophysics news from the week of 9/6/2020

Next week’s night sky:

On Monday, September 14, an extremely rare double transit of Jupiter will happen. What makes this transit special is that not only are there two transits happening at once, the great red spot will also be visible! To find Jupiter, go to stellarium-web.org

Thursday is the new moon. This is a great time to go stargazing because the moon doesn’t blot out any stars.

The double transit with the great red spot.

The butterfly nebula

VLT captured a new image of the butterfly nebula!. But this cosmic bubble of gas, isn’t as calm as the winged insect it resembles. This planetary nebula was produced by the death of one of two stars researchers suspect lie at its center.

Researchers hypothesize that one of the two stars shed its outer layers at the end of its life. They think that the other now flew through the flow of gas from its neighbor, creating this stunning space butterfly. The gas extends up to two light-years from the nebula’s center. This gas can reach temperatures of more than 10,000 degrees, thanks to radiation from the parent stars buried within.

The Butterfly Nebula

New multiwavelength images

Humanity has telescopes that detect different types of light through around the globe and in space. From radio waves to gamma rays, this “multiwavelength” approach to astronomy is crucial to getting a complete understanding of objects in space.

This compilation gives examples of the combined images of multiple telescopes. Each of these images contains data from NASA’s Chandra X-ray Observatory as well as other telescopes. These new images will help research everywhere.

The images are described below.

Top row, left to right:

M82

Messier 82, or M82, is a galaxy that is oriented edge-on to Earth. This gives researchers and their telescopes an interesting view of what happens as this galaxy undergoes bursts of star formation.

Abell 2744

The largest objects in the universe held together by gravity are galaxy clusters. They contain enormous amounts of superheated gas which glows brightly in X-rays and can be observed across millions of light-years between the galaxies. 

Supernova 1987A (SN 1987A)

This was one of the brightest supernova explosions in centuries.

Bottom row, from left to right:

Eta Carinae

What will be the next star in our Milky Way galaxy to explode as a supernova? Researchers aren’t certain, but one candidate is in Eta Carinae, a volatile system containing two massive stars that closely orbit each other. 

Cartwheel Galaxy

This galaxy’s appearance is partly due to a smaller galaxy that passed through the middle of this object. The violent collision produced shock waves that swept through the galaxy and triggered large amounts of star formation. 

Helix Nebula

When a star like the Sun runs out of fuel, it expands and its outer layers puff off, and then the core of the star shrinks. This phase is known as a “planetary nebula,” and astronomers expect our Sun will experience this in about 5 billion years. 

Shotgun-like meteoroid impacts

After NASA’s OSIRIS-REx spacecraft began orbiting the asteroid Bennu, it’s camera recorded small rocks shooting away from the surface at speeds up to 10 feet per second. We have seen more than 300 particles rocket away!

Researchers came up with three possible explanations: meteoroid impacts, thermal stress, and the release of water vapor. 

Bennu rotates every 4.3 hours. As the temperature rises and falls, rocks can crack and break down, possibly ejecting smaller fragments from the surface in the extreme low-gravity environment. The observed particle showers occurred more often in the late afternoon on Bennu, when surface rocks heat up.

The timing of the events also matches up well with head-on meteoroid impacts in the inner solar system thanks to an unseen population of small fragments released from comets as they near the Sun and heat up or even break apart.

Using a computer model, researchers found that sand-size meteoroids, hitting with the force of a shotgun blast, could explain many of the ejection events seen on Bennu. The model works best for asteroids with weak, porous surfaces, which pebble-strewn Bennu resembles.

Studying this meteor should prove to be a remarkable opportunity to expand our knowledge of how active asteroids behave.

Meteor Bennu

To learn more, go here: Photometry of particles ejected from active asteroid (101955) Bennu

Do you have any cool astronomy research news from this week? Share it in the comments below!

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