Posted on by Fraser Cain

Lagoon Nebula By Hubble

This NASA/ESA Hubble Space Telescope image reveals a pair of half a light-year long interstellar ‘twisters’, eerie twisted funnel structures, in the heart of the Lagoon Nebula (M8).

The central hot star, O Herschel 36 (shown here on left, red), is the primary source of the ionising radiation for the brightest region in the nebula, called the ‘Hourglass’. Other hot stars, also present in the nebula, are ionising the outer visible parts of the nebulous material.

This ionising radiation heats up and ‘evaporates’ the surfaces of the clouds (seen as a blue ‘mist’ at the right of the image), and drives violent stellar winds which tear into the cool clouds.

Analogous to the phenomena of tornadoes on Earth, the large difference in temperature between the hot surface and cold interior of the clouds, combined with the pressure of starlight, may produce strong horizontal ‘windshear’ to twist the clouds into their tornado-like appearance.

The Lagoon Nebula and nebulae in other galaxies are sites where new stars are being born from dusty molecular clouds. These regions are the ‘space laboratories’ for astronomers to study how stars form and the interactions between the winds from stars and the gas nearby. By studying the wealth of data revealed by Hubble, astronomers will understand better how stars form in the nebulae.

These colour-coded images are the combination of individual exposures taken in 1995 with Hubble’s Wide Field and Planetary Camera 2 (WFPC2).

Original Source: ESA News Release

Posted on by Fraser Cain

New Perspective on Melas Chasma

This image of the southern part of Valles Marineris, called Melas Chasma, was obtained by the High Resolution Stereo Camera (HRSC) on board the ESA Mars Express spacecraft.

This image was taken at a resolution of approximately 30 metres per pixel. The displayed region is located at the southern rim of the Melas Chasma, centred at Mars latitude 11? S and Mars longitude 286? E. The images were taken on orbit 360 of Mars Express.

This perspective view has been turned in such a way that the observer has a view of the southern scarp, almost 5000 metres high. The basin on the floor of the valley is on the opposite side, bordered by a ridge.

On its flanks it is possible to make out some layering. However, the nature of the bright material, possibly some kind of deposit, is still unknown.

This perspective view was created by using the nadir (vertical view) channel and one stereo channel of the HRSC to produce a digital model of the terrain. Please note that image resolution has been reduced for use on the internet.

Original Source: ESA News Release

Posted on by Fraser Cain

Icy Tethys

Image credit: NASA/JPL/SSI
This view of icy Tethys (1060 kilometers, 659 miles across) shows a large crater in the moon?s southern hemisphere with a central peak. Other surface details of this heavily cratered surface are faintly visible. Cassini was at the time speeding away from the Saturn system on its initial long, looping orbit.

The image was taken in visible light with the narrow angle camera on July 13, 2004, from a distance of about 4.8 million kilometers (3 million miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 97 degrees. The image scale is 29 kilometers (18 miles) per pixel. The image has been magnified by a factor of two to aid visibility.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Original Source: CICLOPS

Posted on by Fraser Cain

Search for Origins Programs Shortlisted

NASA has selected nine studies to investigate new ideas for future mission concepts within its Astronomical Search for Origins Program.

Among the new mission ideas are some that will survey one billion stars within our own galaxy, measure the distribution of galaxies in the distant universe, study dust and gas between galaxies, study organic compounds in space and investigate their role in planetary system formation, and create an optical-ultraviolet telescope to replace the Hubble Space Telescope (HST).

The products from these concept studies will be used for future planning of missions complementing the existing suite of operating missions, including the Hubble and Spitzer Space Telescopes, and developmental missions such as the James Webb Space Telescope and Terrestrial Planet Finder.

Each of the selected studies will have eight months to further develop and refine concepts for missions addressing different aspects of Origins Program science. The Origins Program seeks to address the fundamental questions: “How did we get here?” and “Are we alone?” NASA received 26 proposals in response to this call for mission concepts.

The selected proposals and their principal investigators are:

– BLISS: Revealing the Nature of the Far-IR Universe, Matt Bradford, Jet Propulsion Laboratory, Pasadena, Calif. BLISS will enable far-infrared spectroscopy of the galaxies that make up the far-infrared background out to distances of some of the farthest galaxies known today. BLISS spectral surveys will chart the history of creation of elements heavier than helium and energy production through cosmic time.

– Origins Billion Star Survey (OBSS), Kenneth Johnston, U.S. Naval Observatory, Washington. OBSS will provide a complete census of giant extrasolar planets for all types of stars in our galaxy and the demographics of stars within 30,000 light-years of the sun.

– The Space Infrared Interferometric Telescope (SPIRIT), David Leisawitz, Goddard Space Flight Center, Greenbelt, Md. SPIRIT is an imaging and spectral Michelson interferometer operating in the mid- to far-infrared region of the spectrum. Its very high angular resolution in the far infrared will enable revolutionary developments in the field of star and planet formation research.

– Cosmic Inflation Probe (CIP), Gary Melnick, Smithsonian Astrophysical Observatory, Cambridge, Mass. CIP will measure the shape of cosmic inflation potential by conducting a space-based near-infrared large-area redshift survey capable of detecting galaxies that formed early in the history of the universe.

– HORUS: High ORbit Ultraviolet-visible Satellite, Jon Morse, Arizona State University, Tempe. HORUS will conduct a step-wise, systematic investigation of star formation in the Milky Way, nearby galaxies and the high-redshift universe; the origin of the elements and cosmic structure; and the composition of and physical conditions in the extended atmospheres of extrasolar planets.

– Hubble Origins Probe, Colin Norman, Johns Hopkins University, Baltimore. This mission seeks to combine instruments built for the fifth HST servicing mission: Cosmic Origins Spectrograph and Wide Field Camera 3. This new space telescope at the forefront of modern astronomy will have a unifying focus on the period when the great majority of star and planet formation, heavy element production, black-hole growth and galaxy assembly took place.

– The Astrobiology SPace InfraRed Explorer (ASPIRE) Mission: A Concept Mission to Understand the Role Cosmic Organics Play in the Origin of Life, Scott Sandford, Ames Research Center, Moffett Field, Calif. ASPIRE is an mid- and far-infrared infrared space observatory optimized to spectroscopically detect and identify organic compounds and related materials in space, and understand how these materials are formed, evolve and find their way to planetary surfaces.

– The Baryonic Structure Probe, Kenneth Sembach, Space Telescope Science Institute, Baltimore. The Baryonic Structure Probe will strengthen the foundations of observational cosmology by directly detecting, mapping and characterizing the cosmic web of matter in the early universe, its inflow into galaxies, and its enrichment with elements heavier than hydrogen and helium (the products of stellar and galactic evolution).

– Galaxy Evolution and Origins Probe (GEOP), Rodger Thompson, University of Arizona. GEOP observes more than five million galaxies to study the mass assembly of galaxies, the global history of star formation, and the change of galaxy size and brightness over a volume of the universe large enough to determine the fluctuations of these processes.

More information on NASA’s Origins Program is available on the Internet at:

http://origins.jpl.nasa.gov/

Original Source: NASA News Release

Posted on by Fraser Cain

Public Invited to Help Catalog Mars

NASA scientists have modified a scientific Web site so the general public can inspect big regions and smaller details of Mars’ surface, a planet whose alien terrain is about the same area as Earth’s continents.

After adding ‘computer tools’ to the ‘Marsoweb’ Internet site, NASA scientists plan to ask volunteers from the public to virtually survey the vast red planet to look for important geologic features hidden in thousands of images of the surface. The Web site is located at:

http://marsoweb.nas.nasa.gov/landingsites/index.html

“The initial reason to create Marsoweb was to help scientists select potential Mars landing sites for the current Mars Exploration Rover (MER) mission,” according to Virginia Gulick, a scientist from the SETI Institute, Mountain View, Calif., who works at NASA Ames Research Center, located in California’s Silicon Valley. “The Web site was designed just for Mars scientists so they could view Mars data easily,” she added.

But when the first Mars Exploration Rover landed on Mars in January, the general public discovered Marsoweb. More than a half million ‘unique visitors’ found the page, and the Web experienced about 26.7 million ‘hits’ in January.

“An interactive data map on Marsoweb allows users to view most Mars data including images, thermal inertia, geologic and topographical maps and engineering data that includes rock abundance,” Gulick said. Thermal inertia is a material’s capacity to store heat (usually in daytime) and conduct heat (often at night). “The engineering data give scientists an idea of how smooth or rocky the local surface is,” Gulick explained.

To examine a large number of distinctive or interesting geologic features on the red planet close up would take an army of people because Mars’ land surface is so big. Such a multitude of explorers – modern equivalents of America’s early pioneers – may well survey details of Mars through personal computers.

Researchers hope that volunteers will help with an upcoming Mars imaging experiment. NASA scientists are getting ready for the High Resolution Imaging Science Experiment (HiRISE) that will fly on the Mars Reconnaissance Orbiter (MRO) mission, slated for launch in August 2005. Gulick, co-investigator and education and public outreach lead of the HiRISE team, said that the experiment’s super high-resolution camera will be able to capture images of objects on Mars’ surface measuring about a yard (one meter) wide.

User-friendly ‘Web tools’ soon will be available to the science community and the public to view and analyze HiRISE images beginning in November 2006 and to submit image observation requests, according to HiRISE scientists. If all goes according to plan, a request form will be on the Internet for use by scientists and the public about the time of the Mars Reconnaissance Orbiter launch in 2005. Marsoweb computer scientist Glenn Deardorff, Gulick and other HiRISE team members are now designing Web-friendly software ‘tools’ to allow the public to examine and evaluate HiRISE images.

“We will ask volunteers to help us create ‘geologic feature’ databases of boulders, gullies, craters – any kind of geologic feature that may be of interest,” Gulick explained. “Scientists or students can use these data bases to propose theories about Mars that could be proven by future exploration.”

Preliminary details about Mars Reconnaissance Orbiter HiRISE’s exploration of Mars are on the World Wide Web at:

http://marsoweb.nas.nasa.gov/hirise/

The current Marsoweb site includes animated ‘fly-throughs’ of some Mars locations. The site also permits users to fine-tune Mars images for brightness, contrast and sharpness as well as make other adjustments.

NASA’s Jet Propulsion Laboratory, operated by the California Institute of Technology in Pasadena, Calif., manages the Mars Exploration Rover and Mars Reconnaissance Orbiter missions for the NASA Office of Space Science, Washington, D.C.

Original Source: NASA News Release

Posted on by Fraser Cain

Titan’s Purple Haze

Encircled in purple stratospheric haze, Titan appears as a softly glowing sphere in this colorized image taken one day after Cassini’s first flyby of that moon.

This image shows two thin haze layers. The outer haze layer is detached and appears to float high in the atmosphere. Because of its thinness, the high haze layer is best seen at the moon’s limb.

The image was taken using a spectral filter sensitive to wavelengths of ultraviolet light centered at 338 nanometers. The image has been falsely colored: The globe of Titan retains the pale orange hue our eyes usually see, and both the main atmospheric haze and the thin detached layer have been brightened and given a purple color to enhance their visibility.

The best possible observations of the detached layer are made in ultraviolet light because the small haze particles which populate this part of Titan’s upper atmosphere scatter short wavelengths more efficiently than longer visible or infrared wavelengths.

Images like this one reveal some of the key steps in the formation and evolution of Titan’s haze. The process is thought to begin in the high atmosphere, at altitudes above 400 kilometers (250 miles), where ultraviolet light breaks down methane and nitrogen molecules. The products are believed to react to form more complex organic molecules containing carbon, hydrogen and nitrogen that can combine to form the very small particles seen as haze. The bottom of the detached haze layer is a few hundred kilometers above the surface and is about 120 kilometers (75 miles) thick.

The image was taken with the narrow angle camera on July 3, 2004, from a distance of about 789,000 kilometers (491,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 114 degrees. The image scale is 4.7 kilometers (2.9 miles) per pixel.

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s Office of Space Science, Washington, D.C. The imaging team is based at the Space Science Institute, Boulder, Colorado.

For more information about the Cassini-Huygens mission, visit http://saturn.jpl.nasa.gov and the Cassini imaging team home page, http://ciclops.org.

Posted on by Fraser Cain

Plasma Jets on the Sun Explained

Solar physicists from Lockheed Martin and the Solar Physics and upper-Atmosphere Research Group at the Department of Applied Mathematics of the University of Sheffield, UK have used computer modeling and some of the highest resolution images ever taken of the solar atmosphere to explain the cause of supersonic jets that continuously shoot through the low atmosphere of the Sun.

Their results, which appear as the cover story in tomorrow?s issue of the journal Nature, directly address the origin of these jets, called spicules. The origin of spicules has been a mystery since their discovery in 1877. These findings may well lead to a better understanding of how matter is propelled upward into the solar corona to form the solar wind, a stream of particles continuously emitted by the Sun that sweeps past Earth?s orbit. Disturbances in the solar wind can influence the upper atmosphere and space environment around the Earth and damage satellites in orbit.

?The combination of computer modeling, new high resolution images taken with the Swedish 1-meter Solar Telescope (SST) on the island of La Palma, Spain and data taken simultaneously with two satellites in space, was crucial to figure out how spicules are formed,? said Dr. Bart De Pontieu, one of the main investigators on the study, and solar physicist at the Lockheed Martin Solar and Astrophysics Lab (LMSAL) at the company?s Advanced Technology Center in Palo Alto, Calif. ?We used a computer model to provide the missing link between observations of the surface of the Sun, taken with the MDI instrument onboard ESA/NASA?s Solar and Heliospheric Observatory (SOHO) satellite, and observations of the jets in the low solar atmosphere taken with the SST and NASA?s Transition Region and Coronal Explorer (TRACE) satellite.?

Spicules are jets of gas or plasma propelled upwards from the surface of the Sun. They shoot into its atmosphere or corona at supersonic speeds of about 50,000 miles per hour, and reach heights of 3,000 miles above the solar surface in less than five minutes. Although there are over 100,000 spicules at any time in the Sun?s low atmosphere, or chromosphere, they remain largely unexplained, in part because observations are difficult for objects with so brief a lifetime (about five minutes) and relatively small size (300 miles diameter).

?By simultaneously taking a series of high resolution images with the Swedish Solar Telescope, showing details down to 80 miles, and with the TRACE satellite, we discovered that these jets often occur periodically, usually every five minutes or so, at the same location,? said Professor Robertus Erd?lyi von F?y-Siebenb?rgen, the other main investigator on the study, and professor in applied mathematics at the Solar Physics and upper-Atmosphere Research Group of the University of Sheffield, UK. ?We developed a computer model of the Sun?s atmosphere to show that the periodicity of the spicules is caused by sound waves at the solar surface that have the same five minute period.?

The sound waves at the solar surface are usually damped before they can reach the Sun?s atmosphere. However, De Pontieu, Erd?lyi and Stewart James, a newly graduated Ph.D. under the supervision of Professor Erd?lyi at the University of Sheffield, found that under certain conditions, the sound waves can penetrate through the damping zone and leak into the solar atmosphere. Their computer model shows that after the sound waves leak into the atmosphere, they develop into shock waves that propel matter upwards, forming a spicule.

De Pontieu and his colleagues measured actual waves and oscillations at the surface of the Sun, using these measurements to drive their computer model of the solar atmosphere, which then predicted when jets of gas should shoot up. They were pleasantly surprised to see that the model predicts very accurately when jets should be observed on the Sun with the SST and TRACE.

?Spicules carry more than 100 times the mass into the Sun?s atmosphere required to feed the solar wind,? said De Pontieu, ?which means that they are of huge importance for the balance of how much mass goes into and out of the corona.? With the origins of spicules revealed, it will be possible to study whether the mass that spicules carry into the solar corona contributes to the solar wind. Future studies will also focus on the role the shock waves may play in the higher solar atmosphere or corona.

The results of this study are in a paper published in the journal Nature. The authors are Dr. Bart De Pontieu of Lockheed Martin Solar and Astrophysics Lab, and Professor Robertus Erd?lyi von F?y-Siebenb?rgen and Dr. Stewart James of The Solar Physics and upper-Atmosphere Research Group at the Department of Applied Mathematics, University of Sheffield, UK. Funding for the studies came from NASA, the Particle Physics and Astronomy Research Council of the UK and the Hungarian National Science Foundation.

The Lockheed Martin Solar and Astrophysics Lab is part of Lockheed Martin?s Advanced Technology Center ? the research and development organization of Lockheed Martin Space Systems Company. Headquartered in Bethesda, Md., Lockheed Martin employs about 130,000 people worldwide and is principally engaged in the research, design, development, manufacture and integration of advanced technology systems, products and services. The corporation reported 2003 sales of $31.8 billion.

Original Source: LMSAL News Release

Posted on by Fraser Cain

Swift Moves to Florida to Prepare for Launch

The Swift satellite, which will pinpoint the location of distant yet fleeting explosions that appear to signal the births of black holes, arrived at Kennedy Space Center today in preparation for an October launch.

These enigmatic flashes, called gamma-ray bursts, are the most powerful explosions known in the Universe, emitting more than one hundred billion times the energy than the Sun does in an entire year. Yet they last only a few milliseconds to a few minutes, never to appear in the same spot again.

The Swift satellite is named for the nimble bird, because it can swiftly turn and point its instruments to catch a burst “on the fly” to study both the burst and its afterglow. The afterglow phenomenon follows the initial gamma-ray flash in most bursts; and it can linger in X-ray light, optical light and radio waves for hours to weeks, providing great detail.

“Gamma-ray bursts have ranked among the biggest mysteries in astronomy since their discovery over 35 years ago,” said Dr. Neil Gehrels, Swift Lead Scientist from NASA’s Goddard Space Flight Center in Greenbelt, Md. “Swift is just the right tool needed to solve this mystery. One of Swift’s instruments will detect the burst, while, within a minute, two higher-resolution telescopes will be swung around for an in-depth look. Meanwhile, Swift will ‘e-mail’ scientists and telescopes around the world to observe the burst in real-time.”

The Burst Alert Telescope (BAT) instrument, built by NASA Goddard, will detect and locate about two gamma-ray bursts per week, relaying a 1- to 4-arc-minute position to the ground within about 20 seconds. This position will then be used to “swiftly” re-point the satellite to bring the burst area into the narrower fields of view to study the afterglow with the X-ray Telescope (XRT) and the
UltraViolet/Optical Telescope (UVOT).

These two longer-wavelength (lower-energy) instruments will determine an arc-second position of a burst and the spectrum of its afterglow at visible to x-ray wavelengths. For most of the bursts detected with Swift this data, together with observations conducted with ground-based telescopes, will enable measurement of the redshift, or distance, to the burst source. The afterglow provides crucial information about the dynamics of the burst, but scientists need precise information about the burst in order to locate the afterglow.

Swift notifies the community — which includes museums and the general public, along with scientists at world-class observatories — via the Goddard-maintained Gamma-ray Burst Coordinates Network (GCN). A network of dedicated ground-based robotic telescopes distributed around the world await Swift-GCN alerts.

Continuous burst information flows through the Swift Mission Operations Center, located at Penn State. Penn State, a key U.S. collaborator, built the XRT with University of Leicester (UK) and the Astronomical Observatory of Brera (Italy) and the UVOT with Mullard Space Science Lab (UK).

In addition to providing new clues to the nature of the burst mechanism, Swift’s detection of gamma-ray bursts could provide a bonanza of cosmological data.

“Some bursts likely originate from the farthest reaches, and hence earliest epoch, of the Universe,” said Swift Mission Director John Nousek, professor of astronomy and astrophysics at Penn State. “They act like beacons shining through everything along their paths, including the gas between and within galaxies along the line of sight.”

Theorists have suggested that some bursts may originate from the first generation of stars, and Swift’s unprecedented sensitivity will provide the first opportunity to test this hypothesis.

With NASA’s High-Energy Transient Explorer (HETE-2), now in operation, scientists have determined that at least some bursts involve the explosions of massive stars. Swift will fine-tune this knowledge — that is, answer such questions as how massive, how far, what kind of host galaxies, and why are some bursts so different from others?

While the link between some fraction of bursts with the death of massive stars appears firm, others may signal the merger of neutron stars or black holes orbiting each other in exotic binary star systems. Swift will determine whether there are different classes of gamma-ray bursts associated with a particular origin scenario. Swift may be fast enough to identify afterglows from short bursts, if they exist. Afterglows have only been seen for bursts lasting longer than two seconds. “We may be seeing only half the story so far,” said Gehrels.

The Swift team expects to detect and analyze over 100 bursts a year. When not catching gamma-ray bursts, Swift will conduct an all-sky survey at high-energy “hard” X-ray wavelengths, which will be 20 times more sensitive than previous measurements. Scientists expect that Swift’s enhanced sensitivity relative to earlier surveys will uncover over 400 new supermassive black holes.

Swift, a medium-class explorer mission, is managed by NASA’s Goddard Space Flight Center in Greenbelt, Md., Swift was built in collaboration with national laboratories, universities, and international partners, including the Los Alamos National Laboratory, Penn State University, Sonoma State University, Italy, and the United Kingdom.

Original Source: NASA News Release

Posted on by Fraser Cain

Quintuplet Cluster Imaged by Chandra

This Chandra image presents the first detection of X-rays from stars in the Quintuplet Cluster, an extremely dense young star cluster near the Galactic Center. Because dust blocks visible light from the Galactic Center, the cluster was not discovered until 1990 when it was detected with an infrared telescope. Named for its five brightest stars at infrared wavelengths, the Quintuplet is known to be home to hundreds of stars. Several of these are very massive stars that are rapidly losing gas from their surfaces in high-speed stellar winds.

The bright point-like concentrations of 50 million degree Celsius gas in Chandra’s image are thought to be caused by collisions between the high-speed winds in massive stars that have closely orbiting partners. Colliding stellar winds could also explain the diffuse X-radiation seen between the stars in the Quintuplet. The detection of radio waves from hot gas in this region provides further evidence for vigorous heating of gas by winds from massive stars.

Original Source: Chandra News Release

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Young Stars Thrown Out of the Nursery

Astronomers studying data from the National Science Foundation’s Very Long Baseline Array (VLBA) and other telescopes have concluded that a binary pair of stars forming an energetic microquasar was blasted out of the cluster in which it was born by a supernova explosion some 1.7 million years ago. This is the first time that a fast-moving stellar pair has been tracked back to a specific star cluster.

The scientists analyzed numerous observations of a microquasar called LSI +61 303, and concluded that it is moving away from a star cluster named IC 1805 at nearly 17 miles per second.

A microquasar is a pair of stars, one of which is either a dense neutron star or a black hole, in which material sucked from a “normal” star forms a rapidly-rotating disk around the denser object. The disk becomes so hot it emits X-rays, and also spits out “jets” of subatomic particles at nearly the speed of light.

“In this case, both the microquasar and the star cluster are about 7,500 light-years from Earth and the characteristics of the ‘normal’ star in the microquasar match those of the other stars in the cluster, so we feel confident that the microquasar was shot out from a birthplace in this cluster,” said Felix Mirabel, an astrophysicist at the Institute for Astronomy and Space Physics of Argentina and French Atomic Energy Commission. Mirabel worked with Irapuan Rodrigues, of the Federal University of Rio Grande do Sul, Brazil, and Qingzhong Liu of the Purple Mountain Observatory in Nanjing, China. The astronomers reported their results in the August 1 issue of the scientific journal Astronomy & Astrophysics.

Many neutron stars have been found to be moving rapidly through the sky, leading scientists to conclude that the supernova explosions that produced them were asymmetric, giving a “kick” to the star. LSI +61 303’s motion has carried it about 130 light-years from the cluster IC 1805. The cluster is in the constellation Cassiopeia.

LSI +61 303 contains, the astronomers say, either a black hole or a neutron star with twice the mass of the Sun, orbiting a normal star 14 times more massive than the Sun every 26.5 days. The supernova explosion that produced the black hole or neutron star blew away about twice the mass of the Sun.

The black hole or neutron star originally was much more massive than its companion. The scientists still are unsure about how massive it was. Some evidence, they say, indicates that it was formed only four or five million years ago and exploded a million or so years ago. In that case, the star would have been 60 or more times more massive than the Sun, and would have expelled some 90 percent of its initial mass before the supernova explosion.

On the other hand, they say, the star may have formed some 10 million years ago, in which case it would have been 15-20 times more massive than the Sun.

“Studying this system and hopefully others like it that may be found will help us to understand both the evolution of stars before they explode as supernovae and the physics of the supernova explosions themselves,” Mirabel said.

The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

Original Source: NRAO News Release