Astronomy – The case of the vanishing star

Astronomy can be amazing, beautiful and fill you with awe, but it is also filled with mysteries to rival those of Sherlock Holmes.

From 2001 to 2011 astronomers observed an unstable massive star, poetically named PHL 293B, in the Kinman Dwarf galaxy, which is some 75 million light-years away from Earth. Light spectrum readings showed the blue variable star as being 2.5 million times brighter than the sun.

Images of the Kinman Dwarf galaxy were captured in the past by a camera on the Hubble Space Telescope. But since the galaxy is so far away, researchers have not been able to clearly observe its individual stars.

After a break of a few years, astronomers turned the Very Large Telescope in Chile to point in the direction of the star. Instead of the star, they found … nothing.

The team tried searching several more times using different equipment, but still found no signs of the star. It had simply disappeared!

It is highly unusual for a star of this size to simply vanish. They usually explode in a magnificent way, turning into a supernova which is an extremely bright, super-powerful explosion. Evidence of a supernova such as this would persist for many years to come.

So what happened to PHL 293B?

One possibility is that a dust cloud has passed in front of the star, blocking its lights from reaching our observatories. We saw something similar recently with the dimming and brightening of Betelgeuse.

Another possibility would be that the star collapsed into a black hole, without producing a supernova. This would be highly unusual and contrary to what we know in science to be the result of a star of this size dying.

Until we get better telescopes to see into this region of space, the fate of this star will remain a tantalising mystery. 

This is just one of many mysteries lurking in our solar system, galaxy and in the unexplored universe. 

The Hibiscus Coast Astronomical Society meets every first and third Thursday of the month at Faithfull Funeral Services Hall in Red Beach, 7.30pm. Look for their sign on the road!

Hibiscus Coast Astronomical Society