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Messier Index/M82
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Messier 82 300px A combined Hubble/Spitzer/Chandra image of M 82. w:NASA/w:JPL-Caltech/STScI/CXC/UofA/w:ESA/AURA/JHU. w:J2000 I0NASA/IPAC Extragalactic Database
Results for NGC 3034
http://nedwww.ipac.caltech.edu/
2006-10-27 09 55 52.2 +69 40 47 11.5 ± 0.8 Mly (3.5 ± 0.3 Mpc) 203 ± 4 km/s 9.3 11′.2 × 4′.3 w:Ursa Major Edge on starburst galaxy NGC 3034, UGC 5322, Arp 337, Cigar Galaxy, PGC 28655
Messier 82 (also known as NGC 3034 or the Cigar Galaxy) is the prototype http://adsabs.harvard.edu/abs/2008A%26A...484..711B
2008
June 2008
Star cluster versus field star formation in the nucleus of the prototype starburst galaxy M 82
Barker
S.
de Grijs
R.
Cerviño
M.
Astronomy and Astrophysics
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711–720
10.1051/0004-6361:200809653 nearby w:starburst galaxy about 12 million w:light-years away in the w:constellation w:Ursa Major. The starburst galaxy is five times as bright as the whole w:Milky Way and one hundred times as bright as our galaxy's center.
In 2005, the Hubble revealed 197 young massive clusters in the starburst core. The average mass of these clusters is around 25 M⊙, hence the starburst core is a very energetic and high-density environment. Throughout the galaxy's center, young stars are being born 10 times faster than they are inside our entire Milky Way Galaxy.Happy Sweet Sixteen, Hubble Telescope! Newswise, Retrieved on w:July 30, w:2008.
Messier 81 triggering starburst
thumb|150px|left|Chandra X-ray Observatory image of the Cigar Galaxy
Forming a striking pair in small w:telescopes with nearby spiral M81, M82 is being physically affected by its larger neighbor. Tidal forces caused by w:gravity have deformed this w:galaxy, a process that started about 100 million years ago. This interaction has caused star formation to increase 10 fold compared to "normal" galaxies.
Recently, M82 has undergone at least one tidal encounter with M81 resulting in a large amount of gas being funneled into the galaxy's core over the last 200 Myr. The most recent such encounter is thought to have happened around 2–58 years ago and resulted in a concentrated starburst together with a corresponding marked peak in the cluster age distribution. This starburst ran for up to ~50 Myr at a rate of ~10 M⊙ per year. Two subsequent startbursts followed, the last (~4–6 Myr ago) of which may have formed the core clusters, both super star clusters (SSCs) and their lighter counterparts.
Ignoring any difference in their respective distances from us, the centers of M81 and M82 are visually separated by about 130,000 light-years.Declination separation of 36′.87 and Right Ascension separation of 9′.5 gives via w:Pythagorean theorem a visual separation of 38′.07; Average distance of 11.65 Mly × sin(38′.07) = 130,000 ly visual separation. The actual separation is 300300 200 kly.Separation = sqrt(DM812 + DM822 - 2 DM81 DM82 Cos(38′.07)) assuming the error direction is about the same for both objects.Karachentsev, I. D.; Kashibadze, O. G.
Masses of the local group and of the M81 group estimated from distortions in the local velocity field
3 light years 2006
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http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2006Ap.....49....3K
10.1007/s10511-006-0002-6
Starburst region
In the core of M82, the active starburst region spans a diameter of 500 pc. In optical, there are four high surface brightness regions or clumps (designated A, C, D, and E). These clumps correspond to known sources at w:X-ray, w:infrared, and radio frequencies. Consequently, they are thought to be the least obscured starburst clusters from our vantage point. M82's unique bipolar outflow (or 'superwind') appears to be concentrated on clumps A and C and fueled by the energy injected by w:supernova that occur about once every ten years.
The w:Chandra X-ray Observatory detected fluctuating w:X-ray emissions from a location approximately 600 light-years away from the center of M82. Astronomers have postulated that this fluctuating emission comes from the first known w:intermediate-mass black hole, of roughly 200 to 5000 w:solar masses.Patruno, A.; Portegies Zwart, S.; Dewi, J.; Hopman, C.
The ultraluminous X-ray source in M82: an intermediate-mass black hole with a giant companion
Monthly Notices of the Royal Astronomical Society: Letters
2006
370
1
L6–L9
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2005ApJ...628L..33M
10.1111/j.1745-3933.2006.00176.x M82, like most galaxies, hosts a supermassive black hole at its center with a mass of approximately 3 x 107 solar masses as measured from stellar dynamics. Gaffney, N. I., Lester, D. F., and Telesco, C. M. "The stellar velocity dispersion in the nucleus of M82" w:Astrophysical Journal Letters 1993 April 407 L57–L60 10.1086/186805 http://adsabs.harvard.edu/abs/1993ApJ...407L..57G
Structure
thumb|150px|left|M82 in a small telescope.
M82 was previously believed to be an irregular galaxy. However, in w:2005, two symmetric w:spiral arms were discovered in the w:near-infrared (NIR) images of M82. The arms were detected by subtracting an w:axisymmetric exponential disk from the NIR images. These arms emanate from the ends of the NIR bar and can be followed for the length of 3 disc scales. Even though the arms were detected in the NIR images, they are bluer than the disk. Assuming that the northern part of M82 is nearer to us, which most literature assumes, the observed sense of rotation implies trailing arms. Due to M82's high disk w:surface brightness, nearly edge-on orientation (~80°) with respect to us, and the presence of a complex network of dusty filaments in optical images, the arms were not previously detected.Mayya, Y. D.; Carrasco, L.; Luna, A.
The Discovery of Spiral Arms in the Starburst Galaxy M82
The Astrophysical Journal
2005
628
1
L33–L36
http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2005ApJ...628L..33M
10.1086/432644
External links
Messier 82
M82, SEDS Messier pages
M82 at Chandra
SST: Galaxy on Fire!
M82 at NASA/IPAC EXTRAGALACTIC DATABASE
ESA/Hubble images of M82
M82 The Cigar Galaxy
References
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