An Ultraluminous X-ray Source (ULX) that astronomers had thought was a black hole is really the brightest pulsar ever recorded. ULXs are objects that produce more X-rays than most "normal" X-ray binary systems, in which a star is orbiting a neutron star or a stellar-mass black hole. Black holes in these X-ray binary systems generally weigh about five to thirty times the mass of the sun.

Note: An earlier version of this article appeared on Peter Edmonds' blog.

Recently, beautiful photos of auroras have been in the news. These colorful light shows were generated by solar storms, and provide a vivid demonstration of activity on the Sun affecting the Earth. The pummeling experienced by our home planet is an example of our one-way relationship with the Sun: it can have a noticeable effect on the Earth, but the Earth has a negligible effect on the Sun. Further afield in the galaxy, this isn't always the case. In a few other systems planets can have a big effect on their star, changing their looks in surprising ways.

A spectacular picture of auroras by photographer Mike Taylor taken over Unity Pond in Waldo County, Maine on September 12, 2014. Credit: Mike Taylor photography.

A new study using data from NASA's Chandra X-ray Observatory has shown that a planet is making the star that it orbits act much older than it actually is, as explained in our latest press release. The artist's illustration featured in the main part of this graphic depicts the star, WASP-18, and its planet, WASP-18b.

The destructive results of a powerful supernova explosion reveal themselves in a delicate tapestry of X-ray light, as seen in this image from NASA's Chandra X-Ray Observatory and the European Space Agency's XMM-Newton.

The Eta Carinae star system does not lack for superlatives. Not only does it contain one of the biggest and brightest stars in our galaxy, weighing at least 90 times the mass of the Sun, it is also extremely volatile and is expected to have at least one supernova explosion in the future.

New data from NASA's Chandra X-ray Observatory has provided stringent constraints on the environment around one of the closest supernovas discovered in decades. The Chandra results provide insight into possible cause of the explosion, as described in our press release.

Dr. Harvey Tananbaum at the Smithsonian's Castle Library in May 2006. (Credit: Jim Moran)

On April 20, 2014, Harvey Tananbaum stepped down after 23 years as director of the Chandra X-ray Center (CXC). This event was duly noted in various press releases, but its significance may not have been widely appreciated.

A month or two after Chandra launched in July 1999, I was asked at a Chandra X-ray Center (CXC) senior staff meeting how long I actually expected Chandra to operate. I spontaneously responded: "23 years". Now that is a number not heard very frequently, so there were lots of quizzical looks indicating that an explanation was in order.

Here is a roundup of blog articles for #astrolovers from around the web this week:

A galaxy about 23 million light years away is the site of impressive, ongoing, fireworks. Rather than paper, powder, and fire, this galactic light show involves a giant black hole, shock waves, and vast reservoirs of gas.