New Kind of Gamma Ray Burst is Ultra Long-Lasting

GRB 111209A exploded on Dec. 9, 2011. The blast produced high-energy emission for an astonishing seven hours, earning a record as the longest-duration GRB ever observed. This false-color image shows the event as captured by the X-ray Telescope aboard NASA's Swift satellite. Credit: NASA/Swift/B. Gendre (ASDC/INAF-OAR/ARTEMIS)

According to astronomer Andrew Levan, there’s an old adage in studying gamma ray bursts: “When you’ve seen one gamma ray burst, you’ve seen … only one gamma ray burst. They aren’t all the same,” he said during a press briefing on April 16 discussing the discovery of a very different kind of GRB – a type that comes in a new long-lasting flavor.

Three of these unusual long-lasting stellar explosions have recently been discovered using the Swift satellite and other international telescopes, and one, named GRB 111209A, is the longest GRB ever observed, with a duration of at least 25,000 seconds, or about 7 hours.

“We have observed the longest gamma ray burst in modern history, and think this event is caused by the death of a blue supergiant,” said Bruce Gendre, a researcher now associated with the French National Center for Scientific Research who led this study while at the Italian Space Agency’s Science Data Center in Frascati, Italy. “It caused the most powerful stellar explosion in recent history, and likely since the Big Bang occurred.”

The astronomers said these three GRBs represent a previously unrecognized class of these stellar explosions, which arise from the catastrophic deaths of supergiant stars hundreds of times larger than our Sun. GRBs are the most luminous and mysterious explosions in the Universe. The blasts emit surges of gamma rays — the most powerful form of light — as well as X-rays, and they produce afterglows that can be observed at optical and radio energies.

Swift, the Fermi telescope and other spacecraft detect an average of about one GRB each day. As to why this type of GRB hasn’t been detected before, Levan explained this new type appears to be difficult to find because of how long they last.

“Gamma ray telescopes usually detect a quick spike, and you look for a burst — at how many gamma rays come from the sky,” Levan told Universe Today. “But these new GRBs put out energy over a long period of time, over 10,000 seconds instead of the usual 100 seconds. Because it is spread out, it is harder to spot, and only since Swift launched do we have the ability to build up images of GBSs across the sky. To detect this new kind, you have to add up all the light over a long period of time.”

Levan is an astronomer at the University of Warwick in Coventry, England.

He added that these long-lasting GRBs were likely more common in the Universe’s past.

The number, duration and burst class for GRBs observed by Swift are shown in this plot. Colors link each GRB class to illustrations above the plot, which show the estimated sizes of the source stars. For comparison, the width of the yellow circle represents a star about 20 percent larger than the sun. Credit: Andrew Levan, Univ. of Warwick.
The number, duration and burst class for GRBs observed by Swift are shown in this plot. Colors link each GRB class to illustrations above the plot, which show the estimated sizes of the source stars. For comparison, the width of the yellow circle represents a star about 20 percent larger than the sun. Credit: Andrew Levan, Univ. of Warwick.

Traditionally, astronomers have recognized two types of GRBs: short and long, based on the duration of the gamma-ray signal. Short bursts last two seconds or less and are thought to represent a merger of compact objects in a binary system, with the most likely suspects being neutron stars and black holes. Long GRBs may last anywhere from several seconds to several minutes, with typical durations falling between 20 and 50 seconds. These events are thought to be associated with the collapse of a star many times the Sun’s mass and the resulting birth of a new black hole.

“It’s a very random process and every GRB looks very different,” said Levan during the briefing. “They all have a range of durations and a range of energies. It will take much bigger sample to see if this new type have more complexities than regular gamma rays bursts.”

All GRBs give rise to powerful jets that propel matter at nearly the speed of light in opposite directions. As they interact with matter in and around the star, the jets produce a spike of high-energy light.

Gendre and his colleagues made a detailed study of GRB 111209A, which erupted on Dec. 9, 2011, using gamma-ray data from the Konus instrument on NASA’s Wind spacecraft, X-ray observations from Swift and the European Space Agency’s XMM-Newton satellite, and optical data from the TAROT robotic observatory in La Silla, Chile. The 7-hour burst is by far the longest-duration GRB ever recorded.

Another event, GRB 101225A, exploded on December 25, 2010 and produced high-energy emission for at least two hours. Subsequently nicknamed the “Christmas burst,” the event’s distance was unknown, which led two teams to arrive at radically different physical interpretations. One group concluded the blast was caused by an asteroid or comet falling onto a neutron star within our own galaxy. Another team determined that the burst was the outcome of a merger event in an exotic binary system located some 3.5 billion light-years away.

“We now know that the Christmas burst occurred much farther off, more than halfway across the observable universe, and was consequently far more powerful than these researchers imagined,” said Levan.

Using the Gemini North Telescope in Hawaii, Levan and his team obtained a spectrum of the faint galaxy that hosted the Christmas burst. This enabled the scientists to identify emission lines of oxygen and hydrogen and determine how much these lines were displaced to lower energies compared to their appearance in a laboratory. This difference, known to astronomers as a redshift, places the burst some 7 billion light-years away.

Levan’s team also examined 111209A and the more recent burst 121027A, which exploded on Oct. 27, 2012. All show similar X-ray, ultraviolet and optical emission and all arose from the central regions of compact galaxies that were actively forming stars. The astronomers have concluded that all three GRBs constitute a new kind of GRB, which they are calling “ultra-long” bursts.

Astronomers suggest that blue supergiant stars may be the most likely sources of ultra-long GRBs. These stars hold about 20 times the sun's mass and may reach sizes 1,000 times larger than the sun, making them nearly wide enough to span Jupiter's orbit. Credit: NASA's Goddard Space Flight Center/S. Wiessinger.
Astronomers suggest that blue supergiant stars may be the most likely sources of ultra-long GRBs. These stars hold about 20 times the sun’s mass and may reach sizes 1,000 times larger than the sun, making them nearly wide enough to span Jupiter’s orbit. Credit: NASA’s Goddard Space Flight Center/S. Wiessinger.

“Ultra-long GRBs arise from very large stars,” said Levan, “perhaps as big as the orbit of Jupiter. Because the material falling onto the black hole from the edge of the star has further to fall it takes longer to get there. Because it takes longer to get there, it powers the jet for a longer time, giving it time to break out of the star.”

Levan said that Wolf-Rayet stars best fit the description. “They are born with more than 25 times the Sun’s mass, but they burn so hot that they drive away their deep, outermost layer of hydrogen as an outflow we call a stellar wind,” he said. Stripping away the star’s atmosphere leaves an object massive enough to form a black hole but small enough for the particle jets to drill all the way through in times typical of long GRBs

John Graham and Andrew Fruchter, both astronomers at the Space Telescope Science Institute in Baltimore, provided details that these blue supergiant contain relatively modest amounts of elements heavier than helium, which astronomers call metals. This fits an apparent puzzle piece, that these ultra-long GRBs seem to have a strong intrinsic preference for low metallicity environments that contain just trace amounts of elements other than hydrogen and helium.

“High metalicity long duration GRBs do exist but are rare,” said Graham. “They occur at about 1/25th the rate (per unit of star formation) of the low metallicity events. This is good news for us here on Earth, as the likelihood of this type of GRB going off in our own galaxy is far less than previously thought.”

The astronomers discussed their findings Tuesday at the 2013 Huntsville Gamma-ray Burst Symposium in Nashville, Tenn., a meeting sponsored in part by the University of Alabama at Huntsville and NASA’s Swift and Fermi Gamma-ray Space Telescope missions. Gendre’s findings appear in the March 20 edition of The Astrophysical Journal.

Paper: “The Ultra-long Gamma-Ray Burst 111209A: The Collapse of a Blue Supergiant?” B. Genre et al.

Paper: “The Metal Aversion of LGRBs.” J. F. Graham and A. S. Fruchter.

Sources: Teleconference, NASA, University of Warwick, CNRS

Stunning Aurora Video: Polar Spirits

Polar Lights by Ole Salomonsen

This year, there have been some epic auroral displays, and astrophotographer Ole C. Salomonsen has just released this new video which includes real-time recordings of these “polar spirits.”

“My main focus is on getting the auroras [to] show as close as possible to real-time speed given the time available in a short video,” Salomonsen wrote on Vimeo. “In the film I have tried to show the slower majestic dancing lights, as well as the more faster, dramatic and abstract shows, and finally the auroras in combination with city lights and urban elements.”

Simply stunning, and if you watch closely on the opening sequence you can actually see some whales breaching out in the fjord!

POLAR SPIRITS from Ole C. Salomonsen on Vimeo.

Cosmic Explosion Left Imprint in Fossil Record

Crab Nebula from NASA's Hubble Space Telescope
Ancient iron-loving bacteria may have collected particles from a supernova that exploded about 2.2 million years ago. The Crab Nebula, shown here in this image from NASA's Hubble Space Telescope, is much younger having exploded in 1054. Credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)

Ancient iron-loving bacteria may have scooped up evidence of a nearby supernova explosion 2.2 million years ago, leaving an extraterrestrial iron signature in the fossil record, according to German researchers presenting their findings at a recent meeting of the American Physical Society.

In 2004, German scientists reported finding an isotope of iron in a core sample from the Pacific Ocean that does not form on Earth. The scientists calculated the decay rate of the radioactive isotope iron-60 and determined that the source was from a nearby supernova about 2 million years ago. The blast, they say, was close enough to Earth to seriously damage the ozone layer and may have contributed to a marine extinction at the Pliocene-Pleistocene geologic boundary.

Shawn Bishop, a physicist with the Technical University of Munich in Germany and the primary author of the recent study, wondered if traces of the supernova could be found in the fossil record as well. Some deep sea bacteria soak up iron creating tiny magnetic crystals. These 100-nanometer-wide crystals form long chains inside highly-specialized organelles called magnetosomes which help the bacteria orient themselves to Earth’s magnetic field. Using a core sample from the eastern equatorial Pacific Ocean, Bishop and his team sampled strata spaced about 100,000 years apart. By using a chemical treatment that extracts iron-60 while leaving other iron, the scientists then ran the sample through a mass spectrometer to determine whether iron-60 was present.

And in the layers around 2.2 million years ago, tiny traces of iron-60 appeared.

Although the scientists are not sure which star exploded to rain radioactive iron onto Earth, the scientists refer to a paper from 2002 that points to several supernovae generated in the Scorpius-Centaurus star association. The group of young stars, just 130 parsecs (about 424 light-years) from Earth, has produced 20 supernovae within the past 11 million years.

Source: Nature.com and APS.org “Abstract X8.00002: Search for Supernova 60FE in the Earth’s Fossil Record”, Physical Review Letters, “Evidence for Nearby Supernova Explosions” and 60Fe Anomaly in a Deep-Sea Manganese Crust and Implications for a Nearby Supernova Source.

How to Spot the Antares Launch from NASA Wallops on Wednesday

Sighting prospects for the US Eastern Seaboard during the ascent of Antares. (Credit: The Orbital Sciences Corporation).

A space launch marking a new era is departing from the Virginia coast this Wednesday evening, and if you live anywhere along a wide area of the US Eastern seaboard, you’ll have a great opportunity to witness the launch with your own eyes. Here’s all the information you’ll need to see it, plus some tips for capturing it with your camera.

Orbital Sciences’ Antares rocket will launch from Pad 0A at NASA’s Mid-Atlantic Regional Spaceport based on Wallops Island, Virginia. This will mark not only the first launch of Antares, but the first orbital launch of a liquid-fueled rocket from Wallops. The launch window runs from 5:00 to 8:00 PM EDT (21:00-24:00 UT).

There were some concerns when a technical anomaly shutdown a “Wet Dress Rehearsal” test this weekend at T-16 minutes, but Orbital Sciences has stated that the problems have been resolved and the launch is pressing ahead as planned.

Space shots are a familiar sight to the residents of the Florida Space Coast, but will provide a unique show for residents of the U.S. central Atlantic region. The launch of Antares from Wallops will be visible for hundreds of miles and be over 10° above the horizon for an arc spanning from Wilmington, North Carolina to Washington D.C. and north to the New York City tri-state area as it heads off to the southeast. Antares is a two stage rocket with a 1st stage liquid fueled engine and a solid-fueled 2nd stage. The primary mission for Wednesday’s Antares A-One flight will be to demonstrate the ability for the Antares rocket to place a payload into orbit. If all goes well, Orbital Sciences will join SpaceX this summer in the select club of private companies with the ability provide cargo delivery access to the International Space Station in Low Earth Orbit.

Antares heads to orbit. Artist's concept. (Credit: Orbital Sciences Corperation).
Antares heads to orbit. Artist’s concept. (Credit: Orbital Sciences Corporation).

Antares will deploy a dummy mass simulating the Cygnus module. Also onboard are the Phonesat-1a, -1b, and -1c micro-cubesats and the Dove 1 satellite.

Be sure to watch for the launch of Antares if you live in the region. Find a spot with a low uncluttered eastern horizon and watch from an elevated rooftop or hilltop location if possible. I live a hundred miles west of Cape Canaveral and I’ve followed launches all the way through Main Engine Cutoff and first stage separation with binoculars.

Be sure to also follow the launch broadcast live for any last minute delays via NASA TV or Universe Today will have a live feed as well. Antares is aiming to put the Cygnus test mass in a 250 x 300 kilometre orbit with a 51.6° inclination. This is similar to what will be necessary to head to the ISS, but this week’s launch will not be trailing the ISS in its path. This also means that the launch window can be extended over three hours rather than having to be instantaneous.

If the launch goes at the beginning of the window, the local sun angle over the launch facility will be 30° to the west. Sunset at Wallops on the evening of April 17th occurs at 7:41PM EDT, meaning we could be in for a photogenic dusk launch of Antares if it stretches to the end of the target window.

And speaking of which, a pre-sunset launch means short daytime exposure settings for photography. Be prepared to switch over for dusk conditions if the launch extends into the end of the window. Conditions during twilight can change almost moment-to-moment. One of the most memorable launches we witnessed was the pre-dawn liftoff of STS-131 on April 5th, 2010:

The predawn launch of STS-131 as seen from 100 miles west. (Photo by author).
The predawn launch of STS-131 as seen from 100 miles west. (Photo by author).

Once in orbit, the launch of Antares should generate four visible objects; the test mass payload, the two clam-shell fairings, and the stage two booster. This configuration is similar to a Falcon 9/Dragon launch, minus the solar panel covers. These objects should be visible to the naked eye at magnitudes +3 to +5. The cubesat payloads are tiny and below the threshold of naked eye visibility.

Preliminary visibility for the objects will favor latitudes 0-30° north at dusk to 10-40° at dawn. Keep in mind these predictions could change as the launch window evolves. The next NORAD tracking ID in the queue is 2013-015A. Yesterday’s launch of Anik G1 from Baikonur was just cataloged today as 2013-014A plus associated hardware. The weather is forecast to be 45% “go” for tomorrow’s launch. In the event of a scrub, the next launch window for Antares is April 18-21st.

First orbit of the Cygnus test mass; shadow orientation of the Earth assumes a nominal launch at 22:00UT on April 17th. (Created by the author using Orbitron. TLEs courtesy of (name)
First orbit of the Cygnus test mass; shadow orientation of the Earth assumes a nominal launch at 22:00 UT on April 17th. (Created by the author using Orbitron. Two-Line Elements courtesy of Henry Hallam).

It’ll be exciting to follow this first flight of Antares and its first scheduled mission to the International Space Station this summer. Also watch for the first ever lunar mission to depart Wallops on August 12 with the launch of the Lunar Atmosphere and Dust Environment Explorer (LADEE).

Finally, if you’ve got a pass of the International Space Station this week, keep an eye out for Progress M-17M currently about 10 minutes ahead of the station in its orbit. The unmanned Progress vehicle just undocked yesterday from the station and will be conducting a series of experiments monitoring the interactions of its thrusters with the ionosphere before burning up on reentry over the South Pacific on April 21st.

A pass of the ISS over UK tonite (April 16th) with Progress leading at 20:30UT. (Created by the author in Orbitron).
A pass of the ISS over UK tonite (April 16th) with Progress leading at 20:30UT. (Created by the author in Orbitron).

The ISS and more can be tracked using Heavens-Above. Also, we’ll be tweeting all of the updates and orbital action as it evolves as @Astroguyz. Let us know of those launch sightings both near and far. It’ll be interesting to see what, if any, impact launches visible to a large portion of the U.S. population will have on the public’s perception of spaceflight. Be sure to look up tomorrow night!

ATV-4 Albert Einstein Says ‘Fill ‘er Up!’

Europe's ATV 4 Albert Einstein prepares for its cargo-carrying mission to the International Space Station. Credit: ESA

The next European cargo mission to the International Space Station is preparing for launch, and in this new image, a fuelling operator at Europe’s Spaceport in French Guiana inspects the ATV-4 Albert Einstein as it is filled with propellant. Launch is currently scheduled for June 5, 2013 on an Ariane 5ES rocket to bring about 7 tons of cargo the ISS, including fuel to give the space station an orbital re-boost.


These Automated Transfer Vehicles (ATVs) bring other supplies such as equipment, experiments, water, air, nitrogen, oxygen and fuel.

As the ISS circles Earth, it slowly loses altitude, and occasionally needs a boost to keep it in the proper orbit. ATVs, Progress resupply ships and the thrusters on the Zvezda service module are used to re-boost the station; Soyuz spacecraft are also used “in a pinch” said Johnson Space Center News Chief Kelly Humphries, but they mainly want to save the Soyuz fuel for the departing crew heading back to Earth.

Watch this video as astronaut Jeff Williams demonstrates the acceleration experienced inside the cabin during a reboost on January 24, 2010 (the acceleration starts about 3:50 in the video):

Beautiful Astrophoto: The Moon and the Milky Way Arch

A 21-image mosaic showing the Milky Way and the setting Moon at dawn, at the Convent of Orada in Monsaraz, Portugal, in the Alqueva´s Dark Sky Reserve. Credit and copyright: Miguel Claro.

With the arrival of spring, the Milky Way begins its rise in the sky in the northern hemisphere. Now visible at dawn in the skies over Portugal at dawn, astrophotographer Miguel Claro captured this stunning 21-image mosaic showing the arch of the Milky Way framing the setting Moon from Monsaraz, Portugal in the Alqueva Dark Sky Reserve. In the foreground is the Convent of Orada (dated 1670).

“Near the center at the right of palm trees, the moon shines brightly, although not interfering with the giant arc of the Milky Way where it is possible to distinguish a lot of constellations like Ursa Minor, with the Polaris star to the left of the image,” Claro said via email, “until the swan (Cygnus), with its North America nebula (NGC7000) clearly visible, down to the right, we still find the constellation of Sagittarius and Scorpio, with the brilliant super giant star, Antares.”

Click the images to see larger versions (yes, you really want to ’embiggen!’)

See an annotated version below. Claro used a Canon 60Da – ISO1600 Lens 24mm f/2; Exp. 15 seconds, taken on 06/04/2013 at 5:32 AM local time.


An annotated version of a 21-image mosaic showing the Milky Way and the setting Moon at dawn, at the Convent of Orada in Monsaraz, Portugal, in the Alqueva´s Dark Sky Reserve. Credit and copyright: Miguel Claro.
An annotated version of a 21-image mosaic showing the Milky Way and the setting Moon at dawn, at the Convent of Orada in Monsaraz, Portugal, in the Alqueva´s Dark Sky Reserve. Credit and copyright: Miguel Claro.

The Exoplanet Naming Debate Heats Up

An artist's impression of an extra solar planet Photo credit: David A Hardy, astroart.org Copyright: STFC.

Following last Friday’s press release from the International Astronomical Union (IAU) concerning the naming of extrasolar planets, a heated debate has arisen over two separate but related issues. One is the “official” vs. “popular” names of astronomical objects (and the IAU’s jurisdiction over them) and the other is Uwingu’s intentions in their exoplanet naming contests.

We’re going to talk about the latter first, as this seems to be where much of the contention lies.

As has been reflected in our articles, Universe Today feels that Uwingu has always been upfront that the names chosen in their exoplanet naming contests were never meant to be “officially” recognized by the IAU, but instead are a way to engage the public and to create non-governmental funding for space research. As we said in our article on Nov. 7, 2012 about the first contest that creates a “baby book” of exoplanet names:

The names won’t be officially approved by the International Astronomical Union, but (Alan) Stern said they will be are similar to the names given to features on Mars by the mission science teams (such as the “Jake Matijevic” rock recently analyzed by the Curiosity rover) that everyone ends up using. This also solves the problem of how to come up with names, a task that the IAU has yet to discuss.

Please read these articles on Time and New Scientist which explicitly quote Uwingu CEO Alan Stern as saying the names generated by Uwingu’s contest will not be officially recognized by the IAU, but are a way to get the public involved and excited about exoplanets.

Anyone who implies that Uwingu is like the ‘name a star’ scams, or that they are out to make money to line their own pockets is completely misreading Uwingu’s website and completely missing the point. The profits go towards science research and education. So far Uwingu has given approximately $5,500 to several projects: Astronomers Without Borders, the Galileo Teacher Training Program, the Purdue Multiethnic Training Program, and the Allen Telescope Array for SETI.

Additionally, as the Uwingu Twitter feed confirmed, “No one at Uwingu has ever been paid, we have all worked for free from the start.”

The IAU’s statement on Friday infers that Uwingu is trying to sell “the rights to name exoplanets” and today Uwingu issued a statement that says the IAU’s press release “significantly mischaracterized Uwingu’s People’s Choice contest and Uwingu itself.”

As astronomer Carolyn Collins Petersen wrote on her Spacewriter’s Ramblings blog, nowhere on Uwingu’s website does it say that you’re buying the right to name a planet, as seems to be suggested by the IAU press release.

“If you donate a few dollars, you get to suggest a name,” she wrote. “You donate a few cents and you can vote for the coolest names. The coolest names win prizes. The money goes to research and education.”

And Stern has said the time has come where exoplanets should be named: “The IAU has had ten years to do something about this and they haven’t done anything,” he told Universe Today previously. “What we’re doing might be controversial, but that’s OK. It’s time to step up to the plate and do something.”

And many agree with his point that since the public is obviuosly intrigued and interested in exoplanets, they should be involved in the naming process, if only to suggest names. And as we’ve said before, since the IAU has said it will be difficult to come up with names since there are now hundreds of known explanets, Uwingu’s projects fits the bill of what is needed.

Also from Uwingu’s statement today:

Uwingu affirms the IAU’s right to create naming systems for astronomers. But we know that the IAU has no purview — informal or official — to control popular naming of bodies in the sky or features on them, just as geographers have no purview to control people’s naming of features along hiking trails. People clearly enjoy connecting to the sky and having an input to common-use naming. We will continue to stand up for the public’s rights in this regard, and look forward to raising more grant funds for space researchers and educators this way.

Over the weekend, the debate raged on the various social media outlets, and astronomer Jason Wright wrote a blog post that called out the IAU’s statement, saying it couldn’t be the official IAU policy, because “IAU policy is determined by democratic vote of its commissions and General Assembly. Neither has endorsed any nomenclature for planets, much less the assertions of the press release.”

Wright added that he contacted a member of Commission 53 (the IAU committee that will discuss the future of exoplanet naming) “and learned that they were not consulted for or even informed of this press release before it went out, and that the commission has not established a naming process since it met in Beijing in 2012.”

As far as the difference between “official” and “common” names, the IAU said in their press release that a “clear and systematic system for naming these objects is vital. Any naming system is a scientific issue that must also work across different languages and cultures in order to support collaborative worldwide research and avoid confusion.”

However, many people have pointed out that other sciences — like biology – have scientific names and common names that are both used and there doesn’t appear to be rampant confusion over this.

But stars can have several names as well, as astronomer Stuart Lowe wrote in his Astroblog, “Currently stars can have one proper name but also be in many different catalogues with different IDs.”

Uwingu pointed out in their statement that the star Polaris (its well-known common name!) is also known as the North Star, Alpha Ursae Minoris, HD 8890, HIP 11767, SAO 308, ADS 1477, FK5 907, and over a dozen more designations.

Uwingu also noted how non-scientific, informal names are prevalent in astronomy. Our own Milky Way galaxy is a great example, and “there are many instances where astronomers name things without going through the IAU’s internal process. There are many of features on Mars, ranging from mountains to individual rocks, with names applied by Mars-mission scientists and never adopted by, or even considered by, the IAU. And Apollo astronauts did not seek IAU permission before naming features at their landing sites or from orbit.”

Also, recent press releases reflect where astronomical objects were given names by astronomers without any IAU process such as Supernova Wilson, Galaxy cluster “El Gordo,” and the “Black Eye Galaxy.” “None drew attention from the IAU,” Uwingu said.

Planetary scientist and educator David Grinspoon (who is on Uwingu’s board of advisors) probably summed it up best in a comment he posted on Universe Today: “IAU maintains names for astronomers and that’s fine, but they do not own the sky. Planets are PLACES not just astronomical research objects, and if informal names for these places proliferate, outside of some self-appointed professional “authority”, and the public at large is more engaged in the exoplanet revolution, that is a very good thing indeed.”

Launch! Anik G1 Satellite Aims To Ease Communications Overcrowding

Anik G1 lifts off from Baikonur, Kazakhstan on April 15, 2013. Credit: ILS Launch Services (screencap)

Update, April 16, 8:20 a.m. EDT: Anik G1 was successfully released from the upper stage of the rocket nine hours and 13 minutes after the launch. The satellite is now in orbit above Earth.

A new communications satellite aims to ease the strain of overcrowded communications networks in Latin America, while adding capacity to direct-to-home services in Canada and government and military users across the Americas.

Anik G1 lifted off at 2:36 p.m. EDT (6:36 p.m. UTC) today, April 15, from Baikonur, Kazakhstan. The satellite, carried by a Proton-M rocket, is still undergoing orbital maneuvers as of this writing; the upper Breeze-M stage will fire five times to put Anik G1 in the proper orbit.

These maneuvers should be completed about 9 hours after launch, if all goes well, at which point Anik G1 will separate.

Anik G1 is expected to last 15 years, a typical lifespan for a communications satellite. Once Anik G1 is activated, should all go well with the deployment, Canadian operator Telesat is marketing the satellite as a way to alleviate overcapacity in Latin American telecommunications services.

Continue reading “Launch! Anik G1 Satellite Aims To Ease Communications Overcrowding”

Enjoy Several New Podcasts at Astronomy Cast

Astronomy Cast has recently uploaded several new podcasts, and while we normally post them separately here on Universe Today, since there are a number of them arriving at once, here’s a list of the new ones:

 

We’ve recently had a ‘changing of the guard’ at Astronomy Cast as far as getting things posted to the AC website and getting podcasts loaded to the feed, and are now getting caught up. But as you probably know, Fraser and Pamela now record Astronomy Cast as part of Google+ Hangouts. You can watch them record live at Google+ (they usually record on Mondays at 12 noon Pacific time) or at the AstrosphereVids You Tube channel (where you can watch past Hangouts as well).

Researchers May Have Finally Detected a Dark Matter Particle

The international Super Cryogenic Dark Matter Search (SuperCDMS) has detected what may be the particle that's thought to make up dark matter throughout the Universe.

Dark matter: it’s invisible, it’s elusive, it’s controversial… and it’s everywhere — in the Universe, yes, but especially in the world of astrophysics, where researchers have been exhaustively trying to reveal its true identity for decades.

Now, scientists with the international Super Cryogenic Dark Matter Search (SuperCDMS) experiment are reporting the detection of a particle that’s thought to make up dark matter: a weakly-interacting massive particle, or WIMP. According to a press release from Texas A&M University (whose high-energy physicist Rupak Mahapatra is a principal investigator in the experiment) SuperCDMS has identified a WIMP-like signal at the 3-sigma level, which indicates a 99.8 percent chance of an actual discovery — a “concrete hint,” as it’s being called.

“In high-energy physics, a discovery is only claimed at 5-sigma or better,” Mahapatra said. “So this is certainly very exciting, but not fully convincing by the standards. We just need more data to be sure. For now, we have to live with this tantalizing hint of one of the biggest puzzles of our time.”

If this is indeed a WIMP it will be the first time such a particle has been directly observed, lending more insight into what dark matter is… or isn’t.

Notoriously elusive, WIMPs rarely interact with normal matter and therefore are difficult to detect. Scientists believe they occasionally bounce off, or scatter like billiard balls from, atomic nuclei, leaving behind a small amount of energy capable of being tracked by detectors deep underground, particle colliders such as the Large Hadron Collider at CERN and even instruments in space like the Alpha Magnetic Spectrometer (AMS) mounted on the International Space Station.

A stack of crystal germanium CDMS detectors (Fermilab)
A stack of crystal germanium CDMS detectors (Fermilab)

The CDMS experiment, located a half-mile underground at the Soudan mine in northern Minnesota and managed by the United States Department of Energy’s Fermi National Accelerator Laboratory, has been searching for dark matter since 2003. The experiment uses very sophisticated detector technology and advanced analysis techniques to enable cryogenically cooled (almost absolute zero temperature at -460 degrees F) germanium and silicon targets to search for the rare recoil of dark matter particles.

This newly-announced detection actually comes from data acquired during an earlier phase of the experiment.

“This result is from data taken a few years ago using silicon detectors manufactured at Stanford that are now defunct,” Mahapatra said. “Increased interest in the low mass WIMP region motivated us to complete the analysis of the silicon-detector exposure, which is less sensitive than germanium for WIMP masses above 15 giga-electronvolts [one GeVa is equal to a billion electron volts] but more sensitive for lower masses. The analysis resulted in three events, and the estimated background is 0.7 events.”

Although Mahapatra says the result is certainly encouraging and worthy of further investigation, he cautions it should not be considered a discovery just yet.

“We are only 99.8 percent sure, and we want to be 99.9999 percent sure,” Mahapatra said. “At 3-sigma, you have a hint of something. At 4-sigma, you have evidence. At 5-sigma, you have a discovery.”

“In medicine, you can say you are curing 99.8 percent of the cases, and that’s OK. When you say you’ve made a fundamental discovery in high-energy physics, you can’t be wrong.”

– Dr. Rupak Mahapatra, SuperCDMS principal investigator, Texas A&M University

Advanced 6-inch silicon detectors developed by Mahapatra's lab at Texas A&M
Advanced 6-inch silicon detectors developed by Mahapatra’s lab at Texas A&M

The collaboration will continue to probe this WIMP sector using the SuperCDMS Soudan experiment’s operating germanium detectors and is considering using larger, more advanced 6-inch silicon detectors developed at the Texas A&M’s Department of Electrical Engineering in future experiments.

The team has detailed its results in a paper published in arXiv that eventually will appear in Physical Review Letters. Mahapatra will also announce the results today at 12 p.m. CDT in a talk at the Mitchell Institute for Fundamental Physics and Astronomy.

Source: Texas A&M University

(Read more about dark matter here and here.)