Credit:X-ray: NASA/CXC/Univ. of Geneva, D. Eckert. Optical: SDSS provided by CDS through Aladin.

Astronomers have used data from NASA's Chandra X-ray Observatory to capture a dramatic image of an enormous tail of hot gas stretching for more than a million light years behind a group of galaxies that is falling into the depths of an even-larger cluster of galaxies. Discoveries like this help astronomers learn about the environment and conditions under which the Universe's biggest structures evolve.

Galaxy clusters are the largest structures in the Universe held together by gravity. While galaxy clusters can contain hundreds or even thousands of individual galaxies, the lion's share of mass in a galaxy cluster comes from hot gas, which gives off X-rays, and unseen dark matter. How did these cosmic giants get to be so big?

Credit: X-ray: NASA/CXC/INAF/A. Wolter et al; Optical: NASA/STScI

Astronomers have used NASA's Chandra X-ray Observatory to discover a ring of black holes or neutron stars in a galaxy 300 million light years from Earth.

Credit: X-ray: NASA/CXC/ICE/M.Mezcua et al.;
Infrared: NASA/JPL-Caltech; Illustration: NASA/CXC/A.Hobart

This image shows data from a massive observing campaign that includes NASA's Chandra X-ray Observatory. These Chandra data have provided strong evidence for the existence of so-called intermediate-mass black holes (IMBHs). Combined with a separate study also using Chandra data, these results may allow astronomers to better understand how the very largest black holes in the early Universe formed, as described in our latest press release.

The COSMOS ("cosmic evolution survey") Legacy Survey has assembled data from some of the world's most powerful telescopes spanning the electromagnetic spectrum. This image contains Chandra data from this survey, equivalent to about 4.6 million seconds of observing time. The colors in this image represent different levels of X-ray energy detected by Chandra. Here the lowest-energy X-rays are red, the medium band is green, and the highest-energy X-rays observed by Chandra are blue. Most of the colored dots in this image are black holes. Data from the Spitzer Space Telescope are shown in grey. The inset shows an artist's impression of a growing black hole in the center of a galaxy. A disk of material surrounding the black hole and a jet of outflowing material are also depicted.

The Eagle Nebula (M16)

The Eagle Nebula, also known as Messier 16, contains the young star cluster NGC 6611. It also the site of the spectacular star-forming region known as the Pillars of Creation, which is located in the southern portion of the Eagle Nebula.

J2150-0551

A team of researchers using data from ESA's XMM-Newton X-ray space observatory, NASA's Chandra X-ray Observatory and NASA's Swift X-Ray Telescope has found evidence for the existence of an intermediate-mass black hole (IMBH).

Scientists have strong evidence for the existence of stellar black holes, which are typically five to 30 times as massive as the Sun. They have also discovered that supermassive black holes with masses as large as billions of Suns exist in the centers of most galaxies. They have long been searching for IMBHs that would exist in between these two extremes, which would contain thousands of solar masses. Thought to be seeds that will eventually grow to become supermassive, IMBHs are especially elusive, and thus very few robust candidates have ever been found.

Alpha Centauri

A new study involving long-term monitoring of Alpha Centauri by NASA's Chandra X-ray Observatory indicates that any planets orbiting the two brightest stars are likely not being pummeled by large amounts of X-ray radiation from their host stars, as described in our press release. This is important for the viability of life in the nearest star system outside the Solar System. Chandra data from May 2nd, 2017 are seen in the pull-out, which is shown in context of a visible-light image taken from the ground of the Alpha Centauri system and its surroundings.

Alpha Centauri is a triple star system located just over four light years, or about 25 trillion miles, from Earth. While this is a large distance in terrestrial terms, it is three times closer than the next nearest Sun-like star.

The stars in the Alpha Centauri system include a pair called "A" and "B," (AB for short) which orbit relatively close to each other. Alpha Cen A is a near twin of our Sun in almost every way, including age, while Alpha Cen B is somewhat smaller and dimmer but still quite similar to the Sun. The third member, Alpha Cen C (also known as Proxima), is a much smaller red dwarf star that travels around the AB pair in a much larger orbit that takes it more than 10 thousand times farther from the AB pair than the Earth-Sun distance. Proxima currently holds the title of the nearest star to Earth, although AB is a very close second.

Dave Pooley

It is a pleasure to welcome Dave Pooley as a guest blogger. Dave led the black hole study that is the subject of our latest press release. He is an associate professor at Trinity University in San Antonio, Texas, where he loves doing research with a cadre of amazing undergraduates on topics ranging from gravitational lensing to supermassive black holes to supernova explosions to exotic X-ray binaries to globular clusters. He lives in Austin with his wife, two (soon to be three) children, two cats, and one dog. When he’s not setting up train tracks, watching Daniel Tiger, or analyzing Chandra data, he enjoys cooking, woodworking, and all manner of whisky.

A colleague of mine at MIT once said that the minute the Laser Interferometer Gravitational Wave Observatory (LIGO) detects gravitational waves, it will be one of the most successful physics experiments ever performed, and the next minute, it will immediately become one of the most successful astronomical observatories ever operated.

He was exactly right. The direct detection of gravitational waves was a tremendous success for fundamental physics. We knew that gravitational radiation existed, but to directly detect it was huge. It was a triumph due to the meticulous and brilliant work of the hundreds of people who worked for years and years to make LIGO a success.

And immediately with that first detection, astronomers added gravitational waves to our tool belt of ways to study the universe. With just that first event, which was a merger of two black holes, we learned so much more about black holes than we previously knew. That, in turn, raised even more questions about these intriguing objects. Clearly, 60-solar-mass black holes exist. (That was news to us!) And you make them from 30-solar-mass black holes. (That was news to us too!) So 30-solar-mass black holes exist. (Even that was news to us, too!) But how do you make those? We astronomers have a few ideas, but we’re really not sure. We haven’t figured that out yet. Nature of course, already has.

E0102

Astronomers have discovered a special kind of neutron star for the first time outside of the Milky Way galaxy, using data from NASA's Chandra X-ray Observatory and the European Southern Observatory's Very Large Telescope (VLT) in Chile.

Neutron stars are the ultra dense cores of massive stars that collapse and undergo a supernova explosion. This newly identified neutron star is a rare variety that has both a low magnetic field and no stellar companion.

The neutron star is located within the remains of a supernova — known as 1E 0102.2-7219 (E0102 for short) — in the Small Magellanic Cloud, located 200,000 light years from Earth.