Since Valentine's Day is approaching, it's a good time to combine X-rays from the NASA's Chandra X-ray Observatory (pink) and optical data from the Hubble Space Telescope (red, green, blue) produced by the Space Telescope Science Institute (STScI) into a new image of a ring - not of jewels - but of black holes. The composite image is of Arp 147, a pair of interacting galaxies located about 430 million light years from Earth.
Arp 147 contains the remnant of a spiral galaxy (right) that collided with the elliptical galaxy on the left. This collision has produced an expanding wave of star formation that shows up as a blue ring containing in abundance of massive young stars. These stars race through their evolution in a few million years or less and explode as supernovas, leaving behind neutron stars and black holes.
A fraction of the neutron stars and black holes will have companion stars, and may become bright X-ray sources as they pull in matter from their companions. The nine X-ray sources scattered around the ring in Arp 147 are so bright that they must be black holes, with masses that are likely ten to twenty times that of the Sun.
The image is 54 arcsec (about 115,000 light years across) and this ring galaxy is in the constellation Cetus. Observation time was 11 hours and 49 minutes. Credit: X-ray: NASA/CXC/MIT/S.Rappaport et al, Optical: NASA/STScI
An X-ray source is also detected in the nucleus of the red galaxy on the left and may be powered by a poorly-fed supermassive black hole. This source is not obvious in the composite image but can easily be seen in the X-ray image. Other objects unrelated to Arp 147 are also visible: a foreground star in the lower left of the image and a background quasar as the pink source above and to the left of the red galaxy.
Infrared observations with NASA's Spitzer Space Telescope and ultraviolet observations with NASA's Galaxy Evolution Explorer (GALEX) have allowed estimates of the rate of star formation in the ring. These estimates, combined with the use of models for the evolution of binary stars have allowed the authors to conclude that the most intense star formation may have ended some 15 million years ago, in Earth's time frame.
These results were published in the October 1st, 2010 issue of The Astrophysical Journal but February is a fun time to look at the pictures.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Religious People View Science Favorably But Reject Some Theories - Just Like Everyone Else
- Spider-Man Webbing: How Many Calories Does It Take To Produce All That Silk?
- Battery Leasing And Better Charging Will Make Electric Cars Popular
- Why Climate Scientists Shouldn't Testify Before Congress
- Easter Island Mystery: What Really Happened To Rapa Nui Society?
- Outsourcing: 3 Ways To Stop Medical Research Brain Drain
- Lepton-Flavor-Violating Higgs Decays Fit In With LHCb Anomalies
- "The first three paragraphs of your article clash with the relatively cogent review of the published..."
- "Seven years is too short. 18+ years of warming hiatus is too short too when it pertains to questioning..."
- "Nothing false about it. They are the only two groups that count, meaning everything else is window..."
- "Hank i stand corrected om the NIH issue and i agree that research should be bases not om politics..."
- "I once heard that the FDA was Milton Friedman's prime example of bureaucracy run amok. He would..."
- Biofouling: Ocean acidification changes make a difference
- Cantona: Long series of droughts doomed Mexican city 1,000 years ago
- Flame retardants linked to preterm birth
- Erratic as normal: Arctic sea ice loss isn't predictable in the short term
- Long-necked 'dragon' named Qijianglong discovered in China