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Arp 147: Giant Ring of Black Holes
Arp 147
Arp 147

  • Arp 147 contains a spiral galaxy (right) that collided with an elliptical galaxy (left), triggering a wave of star formation.

  • Many of these newly-born massive stars raced through their lives and ended with supernova explosions, some as black holes.

  • A ring of these black holes can be seen in the Chandra data (pink) around the spiral galaxy.

Just in time for Valentine's Day comes a new image of a ring -- not of jewels -- but of black holes. This composite image of Arp 147, a pair of interacting galaxies located about 430 million light years from Earth, shows 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) in Baltimore, Md.

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.

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. The authors were Saul Rappaport and Alan Levine from the Massachusetts Institute of Technology, David Pooley from Eureka Scientific and Benjamin Steinhorn, also from MIT.

Fast Facts for Arp 147:
Credit  X-ray: NASA/CXC/MIT/S.Rappaport et al, Optical: NASA/STScI
Release Date  February 9, 2011
Scale  Image is 54 arcsec across. (about 115,000 light years across)
Category  Normal Galaxies & Starburst Galaxies
Coordinates (J2000)  RA 03h 11m 18.9s | Dec +01° 18´ 52.99"
Constellation  Cetus
Observation Date  9/13/2009, 9/15/2009
Observation Time  11 hours 49 min
Obs. ID  11280, 11887
Instrument  ACIS
Also Known As Ring Galaxy
Color Code  Optical (Red, Green, Blue); X-ray (Magenta)
Distance Estimate  About 440 million light years
distance arrow
Visitor Comments (20)

That is the future of the Milky Way. Andromeda galaxies when they collide in four billion years. Ultimately they will merge into one big galaxy. In the above pictures, the two galaxies will also probably merge together as one galaxy.

Posted by Michael Amato on Friday, 08.28.15 @ 13:26pm

These are so beautiful.

Posted by whitney on Saturday, 08.22.15 @ 05:43am

Really great, amazing views of galaxies and parts of the universe.

Posted by RAM CHANDRAN on Wednesday, 12.24.14 @ 10:45am

So very amazing. Great explanations of x-ray information, along with images of other wavelengths. Wonderful. Thank you.

Posted by stan on Wednesday, 04.16.14 @ 14:58pm

Very beautiful! I love space. We are a part of it. Congratulations to NASA, further success.

Posted by Michael on Tuesday, 02.14.12 @ 14:43pm

Introspective viewpoints are a challenge to define, perhaps like the elements of space, to locate a viewpoint and understand it from our own limitations.

Posted by Ron lynn on Wednesday, 06.22.11 @ 12:10pm

The universe truly is amazing.

Posted by vedette on Wednesday, 04.27.11 @ 10:49am

Oh my god, these images are so beautiful. I love NASA.

Posted by AcID on Thursday, 03.24.11 @ 08:15am

If possible, I would like to have a picture of the distribution of "dark matter" after the collision of these two galaxy.
Thank you

Posted by Johnny Jiang on Monday, 03.21.11 @ 08:11am

Dear J. Madson,
Thanks for your question. The surface of the Sun is well known to pulsate in a complicated set of harmonics, resulting from internal sound waves that are excited by convection in the interior of the Sun and bounce around inside the Sun. I encourage you to explore more about this intriguing field of "helioseismology" using Google, beginning with:

P.Edmonds, CXC

Posted by P. Edmonds on Wednesday, 03.9.11 @ 11:11am

This is so cool.

Posted by awesome on Monday, 02.28.11 @ 13:44pm

Hello, would you be able to compile photos of the poles of the sun and see any periodocity? and can you see any size diameter variations? can you see a harmonic?

Posted by J Madson on Thursday, 02.24.11 @ 01:32am

These are so beautiful.

Posted by jerry on Friday, 02.18.11 @ 22:34pm

Wow. It seems like there would be a heart-like figure inside the right galaxy.

Posted by Miquel L on Wednesday, 02.16.11 @ 09:26am

The universe never ceases to amaze.

Posted by Jack MCFarland on Tuesday, 02.15.11 @ 23:49pm

Galaxy mergers and "collisions" also interactions have always fascinated me. This particular one is one of the most beautiful.
Has the elliptical passed through the spiral galaxy? That is what seems to have happened, just my own guess on the matter. Many forces at work here.
It is all very beautiful.
Marvin L. S.

Posted by Marvin L. S . on Friday, 02.11.11 @ 16:01pm

Wow, no words to describe the beauty, it's just felt.

Posted by David Barber on Thursday, 02.10.11 @ 19:50pm


Posted by wilfred e thoman on Thursday, 02.10.11 @ 12:23pm

I really love to collect images from NASA. These are truly wonderful and amazing. I love NASA.
Best wishes

Posted by Brahmana Tushar Goswami on Thursday, 02.10.11 @ 08:25am

These photo in x-ray shows to us at least 3 black holes and the cone deep form, for elliptical galaxy a massive black hole in center. A massive Black hole, can be create to the neighbor galaxy, it don't only depend of the accretion mass disk of a galaxy but really of the type of star.

Posted by PECQUERY on Wednesday, 02.9.11 @ 18:38pm

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