See new, spectacular, or mysterious sky images.
- Apathetic Retiree
- Posts: 21556
- Joined: Mon Aug 28, 2006 2:06 pm
- Location: Oklahoma
Hubble and Chandra Spot a Celestial Bauble | heic1018 | 14 Dec 2010
Supernova Bubble Resembles Holiday Ornament | STScI-2010-27 | 14 Dec 2010
Supernova Bubble Resembles Holiday Ornament | CXC 2010 SNR0509 | 14 Dec 2010
Hubble and Chandra Spot a Celestial Bauble
Hubble has spotted a festive bauble of gas in our neighbouring galaxy, the Large Magellanic Cloud. Formed in the aftermath of a supernova explosion that took place four centuries ago, this sphere of gas has been snapped in a series of observations made between 2006 and 2010.
The delicate shell, photographed by the NASA/ESA Hubble Space Telescope, appears to float serenely in the depths of space, but this apparent calm hides an inner turmoil. The gaseous envelope formed as the expanding blast wave and ejected material from a supernova tore through the nearby interstellar medium. Called SNR B0509-67.5 (or SNR 0509 for short), the bubble is the visible remnant of a powerful stellar explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160 000 light-years from Earth.
Ripples seen in the shell’s surface may be caused either by subtle variations in the density of the ambient interstellar gas, or possibly be driven from the interior by fragments from the initial explosion. The bubble-shaped shroud of gas is 23 light-years across and is expanding at more than 18 million km/h.
Astronomers have concluded that the explosion was an example of an especially energetic and bright variety of supernova. Known as Type Ia, such supernova events are thought to result when a white dwarf star in a binary system robs its partner of material, taking on more mass than it is able to handle, so that it eventually explodes.
Hubble’s Advanced Camera for Surveys observed the supernova remnant on 28 October 2006 with a filter that isolates light from the glowing hydrogen seen in the expanding shell. These observations were then combined with visible-light images of the surrounding star field that were imaged with Hubble’s Wide Field Camera 3 on 4 November 2010, and archival X-ray observations taken by NASA’s Chandra X-ray Observatory.
With an age of about 400 years, the supernova might have been visible to southern hemisphere observers around the year 1600, although there are no known records of a “new star” in the direction of the LMC near that time. A much more recent supernova in the LMC, SN 1987A, did catch the eye of Earth viewers and continues to be studied with ground and space-based telescopes, including Hubble.
Credit: NASA/ESA/Hubble Heritage (STScI/AURA); NASA/CXC/SAO/J Hughes (Rutgers)
Know the quiet place within your heart and touch the rainbow of possibility; be
alive to the gentle breeze of communication, and please stop being such a jerk. — Garrison Keillor
- Vacationer at Tralfamadore
- Posts: 18805
- Joined: Mon Jan 21, 2008 1:57 pm
- Location: Alexandria, Virginia
SNR 0509-67.5: Action Replay Of Powerful Stellar Explosion
<<This combination of X-ray and optical images shows the aftermath of a powerful supernova explosion in the Large Magellanic Cloud (LMC), a small galaxy about 160,000 light years from Earth. The debris from this explosion, the supernova remnant SNR 0509-67.5, is shown in a Chandra X-ray Observatory image (upper inset), where the lowest energy X-rays are shown in red, the intermediate energies are green and the highest energies are blue. In 2004, scientists used Chandra to show that SNR 0509-67.5 was likely caused by a Type Ia supernova, using an analysis of the elements, such as silicon and iron, that were detected. A Type Ia is thought to result from a white dwarf star in a binary system that reaches a critical mass and explodes.
The light echo image (lower inset), from the National Science Foundation's Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory (CTIO) in Chile, shows optical light from the original supernova explosion that has bounced off dust clouds in the neighboring regions of the LMC (the light echoes are shown in blue and stars in orange). The light from these echoes travels a longer path than the light that travels straight toward us, and so can be seen hundreds of years after the supernova itself. This image is one of a sequence of 5 images taken between 2001 and 2006 that are shown separately in a time-lapse movie.
The large optical image is from the Magellanic Cloud Emission Line Survey (MCELS), obtained with the University of Michigan's 0.9-meter Curtis Schmidt telescope at CTIO. Emission lines of hydrogen (H-alpha) are red, singly-ionized sulfur is green and doubly-ionized oxygen is blue. The image highlights regions of star formation in the LMC, including supernova remnants and giant structures carved out by multiple supernovas.
For the first time astronomers have used two methods - X-ray observations of a supernova remnant and optical observations of the expanding light echoes from the explosion - to estimate the energy of a supernova explosion. In two separate papers, astronomers concluded that the supernova occurred about 400 years ago (in Earth's time frame), and was unusually bright and energetic. This is the best ever determination of the power of a supernova explosion long after it was visible from Earth.
In the new optical study spectra of the light echo, obtained with Gemini Observatory, were used to confirm that the supernova was a Type Ia and to unambiguously determine the particular class of explosion and therefore its energy. In the new X-ray study, spectra from Chandra and ESA's XMM-Newton Observatory were then independently used to calculate the amount of energy involved in the original explosion, using an analysis of the supernova remnant and state-of-the-art explosion models. The X-ray work also concluded that the explosion was an especially energetic and bright variety of Type Ia supernova, confirming the validity of the explosion models.>>
- Posts: 8200
- Joined: Wed Jul 27, 2005 3:41 pm
- Location: Nebraska
Smile today; tomorrow's another day!