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NGC 6240 Animations
Click for low-resolution animation
Tour of NGC 6240
Quicktime MPEG With closed-captions (at YouTube)

Two large galaxies are colliding and scientists have used Chandra to make a detailed study of an enormous cloud of hot gas that surrounds them. This unusually large reservoir of gas contains as much mass as about 10 billion Suns, spans about 300,000 light years, and radiates at a temperature of more than 7 million degrees. This giant gas cloud, which scientists call a "halo," is located in the system known as NGC 6240. As the galaxies - each about the size and shape of our Milky Way -- merge, the gas contained in individual galaxy has been violently stirred up. This caused a baby boom of new stars that has lasted for at least 200 million years. During this burst of stellar birth, some of the most massive stars raced through their evolution and exploded relatively quickly as supernovas. According to researchers, this created new hot gas enriched with important elements -- such as oxygen, neon, and magnesium -- that expanded into and mixed with cooler gas that was already there. In the future, the two spiral galaxies will probably form one young elliptical galaxy over the course of millions of years. It is unclear, however, how much of the hot gas can be retained by this newly formed galaxy, or if it will be lost to surrounding space. Regardless, the collision in NGC 6240 offers the opportunity to witness a relatively nearby version of an event that was common in the early Universe.
[Runtime: 02:06]

(Credit: NASA/CXC/J. DePasquale)

Click for low-resolution animation
I Can See Your Halo
Quicktime MPEG With closed-captions (at YouTube)

The Universe is enormous and full of empty space. Light from the nearest star outside our solar system has to travel through empty black space for 4.2 years before it reaches our eyes, even though light moves faster than anything else in the Universe and we live in a very densely populated region of space! Yet somehow, despite all this empty space, galaxies crashing into each other is a fairly common sight. One such collision has been caught in this cosmic picture; which shows the enormous cloud of hot gas surrounding two large colliding galaxies called NGC 6240.

The two large spiral galaxies seen in this picture are similar in size and shape to our home galaxy, the Milky Way. Both galaxies are believed to be harbouring supermassive black holes at their centres, which are spiralling towards each other as we speak. It's likely that they will eventually merge together to form an even bigger black hole!

Another consequence of this pile up is the birth of millions of new stars in a 'stellarbaby boom' that has lasted over 200 million years! This was caused by the violent collision, which stirred up the gases in each galaxy. The baby boom resulted in the birth of many stars much more massive than the Sun. These then ended their lives in powerful supernova explosions, pumping material into the enormous gas cloud: a 'halo' of hot gas, which can be seen in this picture. And it contains enough material to make 10 billion Suns!
[Runtime: 02:01]

(Credit: NASA/CXC/April Jubett)

Return to NGC 6240 (April 30, 2013)