Posted on by Nancy Atkinson

36-Dish Australian Telescope Array Opens for Business

Three of 36 antennas of the ASKAP array. Credit: Alexander Cherney

The Australian Square Kilometer Array Pathfinder (ASKAP) is now standing tall in the outback of Western Australia, and will officially be turned on and open for business on Friday, October 5, 2012 . This large array is made up of 36 identical antennas, each 12 meters in diameter, spread out over 4,000 square meters but working together as a single instrument. ASKAP is designed to survey the whole sky very quickly, and astronomers expect to do studies of the sky that could never have been done before.

Below is a beautiful timelapse of the the ASKAP array. The photographer who put the video together, Alexander Cherney says the footage seen here may be quite unique because after the telescope testing phase is completed, any electronic equipment including cameras may not be used near the telescope.


ASKAP provides a wide field-of-view with a large spectral bandwidth and fast survey speed with its phased-array feed or “radio camera,” rather than ‘single pixel feeds’ to detect and amplify radio waves. This new technology allows telescopes to scan the sky more quickly than with traditional methods covers 30 square degrees – a thousand times the size of the full Moon in the sky.

“This will make ASKAP a very powerful survey radio telescope, a 100 times more powerful than any previous survey telescope,” said Brian Boyle, director of the SKA for Australia’s national science agency, speaking to Universe Today in interview earlier this year.

It will provide excellent coverage in a southern hemisphere location, and the radio quiet site at the Murchison Radio Observatory will make it an unprecedented synoptic telescope, according to the ASKAP website, and scientists expect to make advances in understanding galaxy formation and the evolution of the Universe.

While ASKAP will provide advances on its own, later, the dishes will be combined with 60 additional dishes to form part of the world’s largest radio telescope, The Square Kilometer Array. Construction of the SKA is due to begin in 2016.

You can see what the ASKAP looks like anytime by going to their webcam, plus there will be a webcast of the opening ceremonies on Friday at 12 noon – 1pm Western Australian Standard Time, which is 04:00 GMT Friday October 5, 2012 in GMT (midnight US EDT).

Posted on by Jason Major

What Happens When Supermassive Black Holes Merge?

Frame from a simulation of the merger of two black holes and the resulting emission of gravitational radiation (NASA/C. Henze)

The short answer? You get one super-SUPERmassive black hole. The longer answer?

Well, watch the video below for an idea.

This animation, created with supercomputers at the University of Colorado, Boulder, show for the first time what happens to the magnetized gas clouds that surround supermassive black holes when two of them collide.

The simulation shows the magnetic fields intensifying as they contort and twist turbulently, at one point forming a towering vortex that extends high above the center of the accretion disk.

This funnel-like structure may be partly responsible for the jets that are sometimes seen erupting from actively feeding supermassive black holes.

The simulation was created to study what sort of “flash” might be made by the merging of such incredibly massive objects, so that astronomers hunting for evidence of gravitational waves — a phenomenon first proposed by Einstein in 1916 — will be able to better identify their potential source.

Read: Effects of Einstein’s Elusive Gravity Waves Observed

Gravitational waves are often described as “ripples” in the fabric of space-time, infinitesimal perturbations created by supermassive, rapidly rotating objects like orbiting black holes. Detecting them directly has proven to be a challenge but researchers expect that the technology will be available within several years’ time, and knowing how to spot colliding black holes will be the first step in identifying any gravitational waves that result from the impact.

In fact, it’s the gravitational waves that rob energy from the black holes’ orbits, causing them to spiral into each other in the first place.

“The black holes orbit each other and lose orbital energy by emitting strong gravitational waves, and this causes their orbits to shrink. The black holes spiral toward each other and eventually merge,” said astrophysicist John Baker, a research team member from NASA’s Goddard Space Flight Center. “We need gravitational waves to confirm that a black hole merger has occurred, but if we can understand the electromagnetic signatures from mergers well enough, perhaps we can search for candidate events even before we have a space-based gravitational wave observatory.”

The video below shows the expanding gravitational wave structure that would be expected to result from such a merger:

If ground-based telescopes can pinpoint the radio and x-ray flash created by the mergers, future space telescopes — like ESA’s eLISA/NGO — can then be used to try and detect the waves.

Read more on the NASA Goddard new release here.

First animation credit: NASA’s Goddard Space Flight Center/P. Cowperthwaite, Univ. of Maryland. Second animation: NASA/C. Henze.

 

Posted on by Ken Kremer

Antares Commercial Rocket Reaches New Atlantic Coast Launch Pad

Image Caption: Antares Rocket At Wallops Flight Facility Launch Pad. Orbital Sciences Corporation’s Antares rocket at the launch pad at NASA’s Wallops Flight Facility. In a few months, Antares is scheduled to launch a cargo delivery demonstration mission to the International Space Station as part of NASA’s Commercial Orbital Transportation Services (COTS) program. Credit: NASA

At long last, Orbital Sciences Corporation has rolled their new commercially developed Antares medium class rocket to the nation’s newest spaceport – the Mid-Atlantic Regional Spaceport (MARS) at Wallops Island,Va – and commenced on pad operations as of Monday, Oct 1.

The long awaited rollout marks a key milestone on the path to the maiden test flight of the Antares, planned to blast off before year’s end if all goes well.

This is a highly noteworthy event because Antares is the launcher for Orbital’s unmanned commercial Cygnus cargo spacecraft that NASA’s hopes will reestablish resupply missions to the International Space Station (ISS) lost with the shuttle’s shutdown.

“MARS has completed construction and testing operations on its launch complex at Wallops Island, the first all-new large-scale liquid-fuel launch site to be built in the U.S. in decades,” said David W. Thompson, Orbital’s President and Chief Executive Officer.

“Accordingly, our pad operations are commencing immediately in preparation for an important series of ground and flight tests of our Antares medium-class launch vehicle over the next few months. In fact, earlier today (Oct. 1), an Antares first stage test article was transported to the pad from its final assembly building about a mile away, marking the beginning of full pad operations.”

Antares 1st stage rocket erected at Launch Pad 0-A at the Mid-Atlantic Regional Spaceport (MARS) at NASA Wallops Flight Facility in Virginia. Credit: NASA

In about 4 to 6 weeks, Orbital plans to conduct a 30 second long hot fire test of the first stage, generating a total thrust of 680,000 lbs. If successful, a full up test flight of the 131 foot tall Antares with a Cygnus mass simulator bolted on top is planned for roughly a month later.

An ISS docking demonstration mission to the ISS would then occur early in 2013 which would be nearly identical in scope to the SpaceX Falcon 9/Dragon demonstration flight successfully launched and accomplished in May 2012.

The first commercial resupply mission to the ISS by SpaceX (CRS-1) is now set to lift off on Oct. 7 from Cape Canaveral, Florida.

The 700,000 lb thrust Antares first stage is powered by a pair of Soviet era NK-33 engines built during the 1960 and 1970’s as part of Russia’s ill-fated N-1 manned moon program. The engines have since been upgraded and requalified by Aerojet Corp. and integrated into the Ukrainian built first stage rocket as AJ-26 engines.

Image Caption: Antares first stage arrives on the pad at NASA_Wallops on Oct. 1. First stage approaching adapter ring on the right. Credit: NASA

NASA awarded contracts to Orbital Sciences Corp and SpaceX in 2008 to develop unmanned commercial resupply systems with the goal of recreating an American capability to deliver cargo to the ISS which completely evaporated following the forced retirement of NASA’s Space Shuttle orbiters in 2011 with no follow on program ready to go.

“Today’s (Oct. 1) rollout of Orbital’s Antares test vehicle and the upcoming SpaceX mission are significant milestones in our effort to return space station resupply activities to the United States and insource the jobs associated with this important work,” said NASA Associate Administrator for Communications David Weaver. “NASA’s commercial space program is helping to ensure American companies launch our astronauts and their supplies from U.S. soil.”

The public will be invited to watch the Antares blastoff and there are a lot of locations for spectators to gather nearby for an up close and personal experience.

“Antares is the biggest rocket ever launched from Wallops,” NASA Wallops spokesman Keith Koehler told me. “The launches will definitely be publicized.”

Ken Kremer

Posted on by Nancy Atkinson

Year-Long Missions Could Be Added to Space Station Manifest

The International Space Station. Credit: NASA

UPDATE (10/5/12): It’s now official. NASA announced today that the international partners have announced an agreement to send two crew members to the International Space Station on a one-year mission designed to collect valuable scientific data needed to send humans to new destinations in the solar system.

The crew members, one American astronaut and one Russian cosmonaut, will launch and land in a Russian Soyuz spacecraft and are scheduled to begin their voyage in spring 2015. (end of update)

Special crews on board the International Space Station will stay in space for year-long missions instead of the usual six-month expeditions, according to a report by the Russian news agency Ria Novosti.

“The principal decision has been made and we just have to coordinate the formalities,” Alexei Krasnov, the head of Roscosmos human space missions was quoted, saying that the international partners agreed to add the longer-duration missions at the International Astronautical Congress in Italy this week.

This confirms rumors from earlier this year, and pushes ahead the aspirations of Roscosmos to add longer missions to the ISS manifest.

The first yearlong mission will be “experimental” and could happen as early as 2015.

“Two members of the international crew, a Russian cosmonaut and a NASA astronaut will be picked to carry out this yearlong mission,” Krasnov said, adding that planning for the missions has already been underway.

“If the mission proves to be effective, we will discuss sending year-long missions to ISS on a permanent basis,” he said.

For years, the Russian Space Agency indicated that they wanted to do some extra-long-duration mission tests on the ISS, much like the Mars 500 mission that was done by ESA and Russia in 2010–2011 which took place on Earth and only simulated a 500-day mission to Mars.

Since NASA’s long-term plans now include human missions to Mars or asteroids, in April of this year, Universe Today asked NASA’s associate administrator for the Science Mission Directorate, John Grunsfeld about the possibility of adding longer ISS missions in order to test out – in space — the physiological and psychological demands of a human Mars mission. At that time, Grunsfeld indicated longer missions wouldn’t be necessary to do such tests.

“A 500-day mission would have a six-month cruise to Mars and a six-month cruise back,” he said. “When we send a crew up to the ISS on the Soyuz, they spend six months in weightlessness and so we are already mimicking that experiment today.”

However, a year-long mission on the ISS certainly would provide a better rubric to test the longer-term effects of spaceflight and time away from Earth.

This, of course, won’t be the first year-long missions in space. Russian cosmonaut Valery Polyakov spent over 437 consecutive days in space on the Mir Space Station, from January 1994 to March 1995.

For the Mars 500 mission, six volunteers from Russia, Europe and China spent 520 days inside a capsule set up at a research institute in Moscow.

Sources: Ria Novosti, MSNBC

Posted on by Nancy Atkinson

Why is the Sky Dark at Night?

The Minute Physics folks have created another great video, this time explaining why the sky is dark at night. Although at first glance it seems like an easy question to answer, throw in Olbers’ Paradox (the light from an infinite amount of stars should make the night sky completely bright) and it really is quite a complicated matter. In fact, it takes the Minute Physics teams nearly four minutes to explain it all!

Posted on by Nancy Atkinson

Astrophoto: Spectacular 22-Degree Sun Halo Over Kuala Lumpur

A 22 degree Sun halo was seen in Kuala Lumpur on October 2, 2012. Credit: Shahrin Ahmad

Denizens of Kuala Lumpur, Malaysia were treated to a stunning mid-day meteorological phenomenon today (October 2, 2012,) a Sun Halo. A ‘rainbow’ of sorts forms around the Sun (or the Moon, too) when the light is refracted by ice crystals from high cirrostratus clouds.

News reports said the spectacle began around 12.30pm local time, “a sight which drew gasps of wonder from office workers on their way to lunch.”

Shahrin Ahmad captured the beautiful view and sent it to Universe Today.

“This is among the cleanest view of the Halo I’ve seen so far, and created quite a buzz everywhere,” he said.

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Posted on by Fraser Cain

Virtual Star Party – Sep. 30, 2012: Breaking the Rules Edition

We had another fantastic Virtual Star Party Sunday night, with a packed crew of astronomers, including a new face: Bill McLaughlin, streaming from Oregon.

Many many objects joined the party including: Andromeda, Cave Nebula, Pacman Nebula, Double Star Albiero, Wizard Nebula, Cat’s Paw Nebula, Veil Nebula, North America Nebula, Double Cluster, and more.

Astronomers: Stuart Forman, Roy Salisbury, Mike Chasin, Gary Gonella, Bill McLaughlin, David Dickinson.

Commentators: Dr. Pamela Gay, Dr. Thad Szabo, Scott Lewis.

Host: Fraser Cain

Want to experience the star party live? Circle the Virtual Star Party page on Google+, and you’ll get a notification when we post a new event. And speaking of events, we’ve posted next week’s Event here.

Posted on by Jason Major

Mercury’s Surface is Full of Sulfur

The southern portion of Mercury’s Vivaldi basin and outlying rugged terrain

Named for the 17th-century Venetian composer, the southern half of Mercury’s Vivaldi basin is seen in this image acquired on August 26 by NASA’s MESSENGER spacecraft. The 213-km (132-mile) -wide crater’s smooth floor is contrasted by the incredibly rugged terrain beyond its outermost ring — a result of the ejected material that was flung out from the impact site and emphasized by the low angle of illumination.

The floor of the crater remained relatively smooth due to molten material that erupted in the wake of the impact event, flooding the basin.

Recent findings from the MESSENGER mission have revealed variations in Mercury’s surface composition due to volcanism that occurred at different times, as well as a surprising concentration of elements like magnesium and sulfur — much more so than any of the other terrestrial planets.

In results to be published in the Journal of Geophysical Research, scientists report that Mercury’s volcanic smooth plains differ in composition from older surrounding terrains. The older terrain has higher ratios of magnesium to silicon, sulfur to silicon, and calcium to silicon, but lower ratios of aluminum to silicon, suggesting that the smooth plains material erupted from a magma source that was chemically different from the source of the material in the older regions, according to Shoshana Weider of the Carnegie Institution of Washington, the lead author on the paper.

Mercury’s surface was also found to be high in magnesium and sulfur-enriched minerals.

“None of the other terrestrial planets have such high levels of sulfur. We are seeing about ten times the amount of sulfur than on Earth and Mars,” Weider said. “In terms of magnesium, we do have some materials on Earth that are high in magnesium. They tend to be ancient volcanic rocks that formed from very hot lavas. So this composition on Mercury tells us that eruptions of high-temperature lavas might have formed these high-magnesium materials.”

Read: MESSENGER Reveals Mercury’s Colors

The data was gathered with MESSENGER’s X-Ray Spectrometer (XRS) — one of two instruments designed to measure the abundances of many key elements in the top 2mm of Mercury’s crust. XRS detects emissions from elements in the 1-10 kiloelectron-volt (keV) range – specifically, magnesium, aluminum, silicon, sulfur, calcium, titanium, and iron.

Read more on the MESSENGER mission site here.

Inset image: A global mosaic of Mercury from MESSENGER (2011). Image credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Posted on by Nancy Atkinson

Watch Live: A Day in the Life of the Very Large Telescope

Ever wonder what takes place on a daily basis at one of the premier ground-based observatories? The European Southern Observatory (ESO) is celebrating its 50th anniversary, and on October 5, 2012, they will host a free, live event on the web, “A Day in the Life of ESO.” There will be live observations from ESO’s flagship observatory, the Very Large Telescope (VLT), on Cerro Paranal in Chile’s Atacama Desert, as well as talks from astronomers at ESO’s Headquarters in Germany. Members of the public are invited to ask questions in advance of the event, or during the stream, by Facebook, Twitter, and email.

The webcast will be streamed through Livestream.

For the first time in ESO’s history, the VLT will be pointed towards an object in the sky selected by members of the public — the Thor’s Helmet Nebula (NGC 2359). This striking nebula was selected as part of the Choose What the VLT Observes competition. Brigitte Bailleul, from France, won the Tweet Your Way to the VLT! competition, and will travel to the Paranal Observatory in Chile to help make the observations. The live link to Paranal will show the observations and the telescopes on the mountaintop, in the stunning landscape of the Atacama Desert, letting viewers join Brigitte on her trip of a lifetime.

The webcast will run from 9:00 to 15:00 UTC on October 5. It will be hosted by astronomer — and host of the ESOcasts — “Dr J” — Dr. Joe Liske, from ESO. There will also be talks from astronomers at ESO’s Headquarters in Germany, on topics ranging from ESO’s state-of-the-art telescopes, via the latest news from the frontiers of astronomy, to what the life of an astronomer is like. Throughout the day there will be question and answer sessions, and the chance to test your ESO knowledge in a quiz to win some astronomical prizes.

Members of the public are invited to ask questions about the activities at the Paranal Observatory, the talks of the day, or general questions about ESO. You can send us your questions before the event, or during the webcast, in English in the following ways:

Send a tweet @ESO, also using the hashtag #ESO50years.

Write a question on your Facebook wall in which you tag ESO’s Facebook page.

Send an email to [email protected] with the subject ESO50years. Optionally, please include your name and country.

See this ESO webpage for more info and schedule of the webcast.

Posted on by Nancy Atkinson

Surprise! Hot Venus has a Cold Upper Atmosphere

Venus’ terminator – the transitional region between day and night — may fuel an unusually cold region in the atmosphere. Credit: ESA/MPS, Katlenburg-Lindau, Germany

The hottest planet in the Solar System has a surprisingly cold region high in the planet’s atmosphere, according to new findings by the Venus Express spacecraft. While surface temperatures on this hot and hostile planet tops out at 735 Kelvin, or 462 degrees Celsius, ESA scientists say that a layer in the atmosphere about 125 km up has temperatures of around –175 degrees C, and may be cold enough for carbon dioxide to freeze out as ice or snow.

This means this curious cold layer is much colder than any part of Earth’s atmosphere even though Venus is known for its dense, blistering atmosphere and is much closer to the Sun. Additionally, the cold layer appears to be affected by the transitioning between day and night on Venus.

Scientists made the discovery by watching as light from the Sun filtered through the atmosphere to reveal the concentration of carbon dioxide gas molecules at various altitudes along the terminator – the dividing line between the day and night sides of the planet.

Then they combined data about the carbon dioxide concentration with data on atmospheric pressure at each height. The scientists could then calculate the corresponding temperatures.

“Since the temperature at some heights dips below the freezing temperature of carbon dioxide, we suspect that carbon dioxide ice might form there,” said Arnaud Mahieux of the Belgian Institute for Space Aeronomy and lead author of the paper reporting the results in the Journal of Geophysical Research.

The temperature profile along the terminator for altitudes of 70–160 km above the surface of Venus. Credit: ESA/AOES–A.V. Bernus

Source: ESA

Clouds of small carbon dioxide ice or snow particles should be very reflective, perhaps leading to brighter than normal sunlight layers in the atmosphere.

“However, although Venus Express indeed occasionally observes very bright regions in the Venusian atmosphere that could be explained by ice, they could also be caused by other atmospheric disturbances, so we need to be cautious,” said Mahieux.

The study also found that the cold layer at the terminator is sandwiched between two comparatively warmer layers.

“The temperature profiles on the hot dayside and cool night side at altitudes above 120 km are extremely different, so at the terminator we are in a regime of transition with effects coming from both sides.

“The night side may be playing a greater role at one given altitude and the dayside might be playing a larger role at other altitudes.”

Similar temperature profiles along the terminator have been derived from other Venus Express datasets, including measurements taken during the transit of Venus earlier this year.

Models are able to predict the observed profiles, but further confirmation will be provided by examining the role played by other atmospheric species, such as carbon monoxide, nitrogen and oxygen, which are more dominant than carbon dioxide at high altitudes.

“The finding is very new and we still need to think about and understand what the implications will be,” says Håkan Svedhem, ESA’s Venus Express project scientist. “But it is special, as we do not see a similar temperature profile along the terminator in the atmospheres of Earth or Mars, which have different chemical compositions and temperature conditions.”