APOD: M82: Starburst Galaxy with a Superwind (2011 Oct 06)

[APOD Robot]

M82: Starburst Galaxy with a Superwind

Explanation: Also known as the Cigar Galaxy for its elongated visual appearance, M82 is a starburst galaxy with a superwind. In fact, through ensuing supernova explosions and powerful winds from massive stars, the burst of star formation in M82 is driving the prodigous outflow of material. Evidence for the superwind from the galaxy's central regions is clear in this sharp composite image, based on data from small telescopes on planet Earth. The composite highlights emission from filaments of atomic hydrogen gas in reddish hues. The filaments extend for over 10,000 light-years. Some of the gas in the superwind, enriched in heavy elements forged in the massive stars, will eventually escape into intergalactic space. Triggered by a close encounter with nearby large galaxy M81, the furious burst of star formation in M82 should last about 100 million years or so. M82 is 12 million light-years distant, near the northern boundary of Ursa Major.

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[Beyond]

Hmm... The wider part of the red coming out of the center of the galaxy in the APOD is at about 7 Oclock. In the Stargazers photo it is at about 10 Oclock.

[neufer]

Mystery object in Starburst Galaxy M82 possible micro-quasar
14 April 2010

[b][color=#0000FF]An image of galaxy M82 taken by the Spitzer Telescope. Supernova explosions in the core of the galaxy have produced a hot wind which can be seen escaping from galaxy in this infra-red image where dust emission is coloured red. Credit: NASA/JPL-Caltech.[/color][/b]

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[b][color=#0000FF]Radio image of M82 made with the MERLIN and VLA telescopes. The resolution of the main image (the size of a pixel) is 100 milliarcseconds, the diameter of a 1 pence coin when viewed at a distance of 40 km. Insets show MERLIN images from April 25th and May 3rd 2009 demonstrating the sudden appearance of the mystery object. The resolution of these inset images is 40 mas. All images are at a frequency of 5 GHz. Credit: T.W.B. Muxlow, University of Manchester.[/color][/b]

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<<Radio astronomers at the University of Manchester’s Jodrell Bank Observatory have discovered a strange new object in a nearby galaxy. The object, which appeared very suddenly in radio wavelengths and shows no signs of going away, does not appear to be like anything that has been seen in the Milky Way.

The galaxy, known as M82, is 10 million light years away and is a stellar production line churning out new stars at a prodigious rate. However, many of these stars die quickly in huge explosions, with a new supernova explosion occurring every 20 to 30 years.

“The new object, which appeared in May 2009, has left us scratching our heads – we’ve never seen anything quite like this before,” said Dr Muxlow. “The object turned on very rapidly within a few days and shows no sign of decaying in brightness over the first few months of its existence. The new young supernova explosions that we were expecting to see in M82 brighten at radio wavelengths over several weeks and then decay over several months, so that explanation seems unlikely.” The plausibility of a supernova explanation was further undermined when very accurate positional monitoring by the UK network of radio telescopes, MERLIN, tentatively detected a change in position for the object over the first 50 days. This was equivalent to an apparent superluminal motion of over 4 times the speed of light. Such large apparent velocities are not seen in supernova remnants and are usually only found with relativistic jets ejected from accretion disks around massive black hole systems.

The nucleus of M82, like most major galaxies, is expected to contain a super-massive black hole. The new detection lies at a position close to, but several arcseconds from the dynamical centre of M82 – far enough away that it would seem unlikely that this object is associated with the central collapsed core of this galaxy.

The new source could be the first radio detection of an extragalactic ‘micro-quasar’. Examples of such systems within the Milky Way are found as X-ray binaries with relativistic jets ejected from an accretion disk around a collapsed star fuelled with material dragged from a close binary companion. However, this object would be brighter than any Galactic example yet detected, has lasted months longer than any known X-ray binary, and lies at a position in M82 where no variable X-ray source has yet been detected. If this object is an extragalactic micro-quasar, it would be the first that has been detected at radio wavelengths. The very high luminosity suggests that it is likely to be associated with a massive black hole system of some type; however this and its longevity imply that this type of object is extremely unusual and has not yet been seen within our Galaxy.

“We have just started processing data from an array of 20 radio telescopes across the Earth were taken for the central nuclear region of M82. These images will allow us to examine the structure of the new radio source in detail. However, processing such huge datasets takes significant amounts of computing effort and painstaking work. Only then will we be able to see if it is some rare form of micro-quasar. Watch this space…!” said Muxlow.>>

[Ann]

M82 is an interesting example of a starburst galaxy where the very star formation itself is rapidly depleting the galaxy of gas and depriving it of its ability to form new stars in the future.

In M82, all the action is taking place near the center of the galaxy. Note the intermediate color and smooth "texture" of the disk: There are few or no young star clusters here, and the disk is dominated by an evenly distributed intermediate population of A-, F- and G-type stars, similar to Sirius, Procyon and the Sun. Here, star formation has apparently already ended, probably at least 500 million years ago or so. Near the center, however, huge clusters of supermassive stars have recently formed and likely also exploded as supernovae, sending those tremendous billowing super-winds of ionized glowing red hydrogen gas out of the galaxy. Note the large amounts of brown dust which is a by-product of massive star formation.

That's a very nice APOD! Thanks, Dietmar Hager, Torsten Grossmann, Robert Nemiroff and Jerry Bonnell!

Ann

[Boomer12k]

In close up, it looks like lots of Hydrogen (I assume) bubbles. That is an awesome picture.

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[nstahl]

I'm guessing with the M81 encounter and its results that became a tough place to live, what with all the supernovae and their radiation. And of course such a future lies in store for the Milky Way (M0?) when Andromeda flies by in a while. Exciting times.

Nice APOD.

neufer, let's consider an alien race wanting to invade us and needing to point its propulsion system right at us to slow down. If it suddenly turned on out in the middle of nowhere we would be highly suspicious, but if it showed up in the middle of an active galaxy like M82 our scientists would just theorize about superluminal effects and such. Food for thought. And watch the skies!

[neufer]

In close up, it looks like lots of Hydrogen (I assume) bubbles. That is an awesome picture.

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Click to play embedded YouTube video.

[orin stepanek]

Click to play embedded YouTube video.

OMG; Mad Pumpkin

[supamario]

WHAT!? I was expecting more QR codes! Thats it, I'm not coming here anymore and taking my 2 cents with me!

Excellent photo!
And to think, M82 is around the same distance to M81 as the Magellanic Clouds are to the Milky Way, except, M82 is far brighter.
What a spectacular sight M82 must be to any observers in M81.

[neufer]

2 cents: Ignoring any difference in their respective distances from us, the centers of M81 & M82 are visually separated by about 130,000 light-years. The actual separation is more like 300,000 light-years.

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WHAT!? I was expecting more QR codes! Thats it, I'm not coming here anymore and taking my 2 cents with me!

Excellent photo!

And to think, M82 is around the same distance to M81 as the Magellanic Clouds are to the Milky Way, except, M82 is far brighter.

What a spectacular sight M82 must be to any observers in M81.

What a scary sight M82 must be to any observers in M81.

The LMC lies about 160,000 light years away,
while the SMC is around 200,000 light years.

[Chris Peterson]

What a scary sight M82 must be to any observers in M81.

What would be scary about a faint gray blob spanning 10 or 15 degrees of the sky, invisible except in dark sky sites? Is the Milky Way scary?

[neptunium]

Gee, what an interesting photo! I've been trying to see the galaxy through my telescope, but nowadays the Big Dipper is getting low in the sky...

And neufer, any reason why you take up so much empty space in your comments?

Like this???

[Beyond]

Space - the final frontier.

It's a really big place.

With a lot of -not much- between everything.

Like this.

[neptunium]

Now I gotcha!

[neptunium]

And neufer, any reason why you take up so much empty space in your comments?

Like this???

Or this???

[saturn2]

Galaxia M82 has a look very interesting.
This is a peculiar galaxy.

[neufer]

What a scary sight M82 must be to any observers in M81.

What would be scary about a faint gray blob spanning 10 or 15 degrees of the sky, invisible except in dark sky sites?

There would be a SN1987a supernova going off about every generation for one
(; not to mention the micro-quasars).

Is the Milky Way scary?

It can be.