Astronomy Picture of the Day
Posted By admin On November 12, 2011 @ 8:25 pm In Photo Essays | Comments Disabled
[1]Credit: X-ray: XMM-Newton [2], Chandra [3] / IR: WISE [4], Spitzer [5]
Explanation: In 185 AD, Chinese astronomers [6] recorded the appearance of a new star in the Nanmen asterism – a part of the sky identified with Alpha and Beta Centauri on modern star charts. The new star was visible for months and is thought to be the earliestrecorded supernova [7]. This multiwavelength [8] composite image from orbiting telescopes of the 21st century, XMM-Newton and Chandra in X-rays, and Spitzer and WISE in infrared, shows RCW 86 [9], understood to be the remnant of that stellar explosion [10]. The false-color view [11] traces interstellar gas heated by the expanding supernova shock wave at X-ray energies (blue and green) and interstellar dust radiating at cooler temperatures in infrared light (yellow and red). An abundance of the element iron and lack of a neutron star or pulsar in the remnant suggest that the original supernova was Type Ia. Type Ia supernovae [12] are thermonuclear explosions that destroy [13] a white dwarf star as it accretes material from a companion in a binary star system. Shock velocities measured in [14] the X-ray emitting shell and infrared dust temperatures indicate that the remnant is expanding extremely rapidly into a remarkable low density bubble created before the explosion by the white dwarf system. Near the plane of our Milky Way [15] Galaxy, RCW 86 is about 8,200 light-years away and has an estimated radius of 50 light-years.
Article printed from Recorder Online: http://www.berthoudrecorder.com
URL to article: http://www.berthoudrecorder.com/2011/11/12/astronomy-picture-of-the-day-87/
URLs in this post:
[1] Image: http://www.berthoudrecorder.com/wp-content/uploads/2011/11/rcw86_IRXraycomposite2811.jpg
[2] XMM-Newton: http://xmm.esac.esa.int/
[3] Chandra: http://chandra.haravard.edu/
[4] WISE: http://wise.ssl.berkeley.edu/
[5] Spitzer: http://spitzer.caltech.edu/
[6] Chinese astronomers: http://en.wikipedia.org/wiki/Chinese_astronomy
[7] recorded supernova: http://arxiv.org/abs/astro-ph/0301603
[8] multiwavelength: http://coolcosmos.ipac.caltech.edu/cosmic_classroom/multiwavelength_astronomy/multiwavelength_astronomy/
[9] shows RCW 86: http://www.spitzer.caltech.edu/news/1324-ssc2011-09-NASA-Telescopes-Help-Solve-Ancient-Supernova-Mystery
[10] stellar explosion: http://apod.nasa.gov/apod/ap060728.html
[11] false-color view: http://www.spitzer.caltech.edu/images/4777-nhsc2011-09b-All-Eyes-on-Oldest-Recorded-Supernova
[12] Type Ia supernovae: http://en.wikipedia.org/wiki/Type_Ia_supernova
[13] destroy: http://apod.nasa.gov/apod/ap110430.html
[14] measured in: http://arxiv.org/abs/1108.1207
[15] Milky Way: http://apod.nasa.gov/apod/ap110520.html
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