RSSArchive for May, 2010

Space telescope reveals hidden cosmos

WISE space telescope image of the Heart and Soul nebulae

Covering an area of the sky over 10 times as wide as the full Moon, the Heart and Soul nebulae form a vast star-forming complex about 6,000 light-years from Earth.

  • Infrared telescope, good for seeing cold objects
  • Making survey of the entire sky
  • Has spotted 60,000 asteroids so far

NASA’s Wide-field Infrared Survey Explorer, or WISE, has captured a huge mosaic of two bubbling clouds in space, known as the Heart and Soul nebulae.

The space telescope, which has completed about 74% of its infrared survey of the entire sky, has already captured nearly one million frames like the ones making up the newly released mosaic.

“This new image demonstrates the power of WISE to capture vast regions,” said Ned Wright, the mission’s principal investigator at UCLA. “We’re looking north, south, east and west to map the whole sky.”

The Heart nebula is named after its resemblance to a human heart; the nearby Soul nebula happens to resemble a heart too, but only the symbolic kind with two lobes.

The nebulae, which are about 6,000 light-years away, are both massive star-making factories, shown by the giant bubbles blown into surrounding dust by the radiation and “winds” from the stars.

The infrared vision of WISE allows it to see into the cooler and dustier crevices of clouds like these, where gas and dust are just beginning to collect into new stars.

The new image was captured as WISE circled over Earth’s poles, scanning strips of the sky. It is stitched together from 1,147 frames, taken with a total exposure time of three-and-a-half hours.

An artist's impression of the WISE space telescope

WISE carries an infrared telescope cooled by solid hydrogen.

WISE will complete its first map of the sky in July 2010. It will then spend the next three months surveying much of the sky a second time, before the solid-hydrogen coolant needed to chill its infrared detectors runs dry.

The first public instalment of the WISE catalogue will be released in summer 2011.

About 960,000 WISE images have been beamed down from space to date. Some show ethereal star-forming clouds, while others reveal the ancient light of very remote, powerful galaxies.

The Solar System’s rocky rubble

Many of the WISE images are speckled with little dots … asteroids in our Solar System. So far, the mission has seen more than 60,000 asteroids, most of which lie in the main belt between Mars and Jupiter.

About 11,000 of these objects are newly discovered, and about 50 of them belong to a class of near-Earth objects, which have paths that take them within about 48 million kilometres (30 million miles) of Earth’s orbit.

One goal of the WISE mission is to study asteroids throughout our Solar System and to find out more about how they vary in size and composition. Infrared helps with this task because it can get better size measurements of the space rocks than visible light.

“Infrared will help us understand more about the sizes, properties, and origins of asteroids near and far,” said Amy Mainzer, the principal investigator of NEOWISE, a program to study and catalogue asteroids seen by WISE (the acronym comes from combining near-Earth object, or NEO, with WISE).

WISE will also study the Trojans, asteroids that run along with Jupiter in its orbit around the Sun in two packs — one in front of and one behind the gas giant planet. It has seen more than 800 of these objects, and by the end of the mission, should have observed about half of all 4,500 known Trojans. The results will influence competing concepts about how the outer planets evolved.

Comets have also made their way into WISE images, with more than 72 seen so far, about a dozen of them new. WISE is taking a census of the types of orbits comets ride in. The data will help explain what kicks comets out of their original, more distant orbits, sending them in toward the Sun.

Adapted from information issued by NASA / JPL-Caltech / UCLA.

New star-forming regions found

The Orion Nebula

The Orion Nebula, an example of an H II gas cloud, where hydrogen gas is ionised and glows.

  • Previously-unknown star forming regions found
  • Scattered through the Milky Way
  • Hold chemical clues to stellar evolution

Astronomers studying the Milky Way have discovered a large number of previously-unknown regions where massive stars are being formed. Their discovery provides important new information about the structure of our home Galaxy and promises to yield new clues about the chemical composition of the Galaxy.

“We can clearly relate the locations of these star-forming sites to the overall structure of the Galaxy,” said Thomas Bania, of Boston University.

“Further studies will allow us to better understand the process of star formation and to compare the chemical composition of such sites at widely different distances from the Galaxy’s centre.”

Bania worked with Loren Anderson of the Astrophysical Laboratory of Marseille in France, Dana Balser of the US National Radio Astronomy Observatory (NRAO), and Robert Rood of the University of Virginia.

Gas clouds hidden from view

Artist's impression of the Milky Way looking from above

Our current understanding of the major components of our galaxy, the Milky Way (artist's impression shown here). Astronomers have found dozens more star-forming regions known as H II clouds.

The star-forming regions the astronomers sought, called H II regions, are sites where hydrogen atoms are ionised, or stripped of their electrons, by the intense radiation of the massive, young stars. To find these regions hidden from visible-light detection by the Milky Way’s gas and dust, the researchers used infrared and radio telescopes.

“We found our targets by using the results of infrared surveys done with NASA’s Spitzer Space Telescope and of surveys done with the US National Science Foundation’s (NSF) Very Large Array (VLA) radio telescope,” Anderson said. “Objects that appear bright in both the Spitzer and VLA images we studied are good candidates for H II regions.”

The astronomers then used the NSF’s giant Robert C. Byrd Green Bank Telescope (GBT) in West Virginia, an extremely sensitive radio telescope. With the GBT, they were able to detect specific radio frequencies emitted by electrons as they recombined with protons to form hydrogen.

This evidence of recombination confirmed that the regions contained ionised hydrogen and thus are H II regions.

Our Galaxy’s chemical mix

Further analysis enabled the astronomers to determine the locations of the H II regions.  They found concentrations of the regions at the end of the Galaxy’s central elongated region and in its spiral arms. Their analysis also showed that 25 of the regions are farther from the Galaxy’s centre than the Sun.

“Finding the ones beyond the [Sun’s location] is important, because studying them will provide important information about the chemical evolution of the Galaxy,” Bania said. “There is evidence that the abundance of heavy elements changes with increasing distance from the Galactic centre.”

“We now have many more objects to study and improve our understanding of this effect.”

Adapted from information issued by NRAO / NASA / JPL-Caltech / R. Hurt (SSC-Caltech) / HHT (AURA / STScI / NASA).

Mars lander doesn’t phone home

Two images of the Phoenix Mars lander taken from Martian orbit in 2008 and 2010

Two images of the Phoenix Mars lander taken from Martian orbit in 2008 and 2010. The 2008 lander image shows two relatively blue spots on either side corresponding to the spacecraft's clean circular solar panels. In the 2010 image scientists see a dark shadow that could be the lander body and eastern solar panel, but no shadow from the western solar panel.

  • No contact with Phoenix Mars Lander
  • Completed its mission in 2008
  • Solar panels appeared damaged from ice

NASA’s Phoenix Mars Lander has ended operations after repeated attempts to contact the spacecraft were unsuccessful. And new image transmitted by NASA’s Mars Reconnaissance Orbiter (MRO) shows signs of severe ice damage to the lander’s solar panels.

“The Phoenix spacecraft succeeded in its investigations and exceeded its planned lifetime,” said Fuk Li, manager of the Mars Exploration Program at NASA’s Jet Propulsion Laboratory. “Although its work is finished, analysis of information from Phoenix’s science activities will continue for some time to come.”

Last week, NASA’s Mars Odyssey orbiter flew over the Phoenix landing site 61 times during a final attempt to communicate with the lander. No transmission from the lander was detected. Phoenix also did not communicate during 150 flights in three earlier listening campaigns this year.

Earth-based research continues on discoveries that Phoenix made during summer conditions at the far-northern site where it landed May 25, 2008. The solar-powered lander completed its three-month mission and kept working until sunlight waned two months later.

Phoenix was not designed to survive the dark, cold, icy winter. However, the slim possibility that Phoenix survived could not be eliminated without listening for the lander after abundant sunshine returned.

A view of one of Mars Phoenix Lander's two circular solar panels.

A view of one of Mars Phoenix Lander's two circular solar panels. Scientists think winter ice might have broken one of the panels.

Ice damage

The MRO image of Phoenix taken this month by the High Resolution Imaging Science Experiment, or HiRISE, camera on board the spacecraft suggests the lander no longer casts shadows the way it did during its working lifetime.

“Before and after images are dramatically different,” said Michael Mellon of the University of Colorado in Boulder, a science team member for both Phoenix and HiRISE.

“The lander looks smaller, and only a portion of the difference can be explained by accumulation of dust on the lander, which makes its surfaces less distinguishable from surrounding ground.”

Apparent changes in the shadows cast by the lander are consistent with predictions of how Phoenix could be damaged by harsh winter conditions. It was anticipated that the weight of a carbon-dioxide ice build-up could bend or break the lander’s solar panels. Mellon calculated hundreds of kilograms of ice probably coated the lander in mid-winter.

A view of the Phoenix Mars Lander's arm and scoop

A view of the Phoenix Mars Lander's arm and scoop, with a solar panel in the foreground.

Interesting chemistry

During its mission, Phoenix confirmed and examined patches of the widespread deposits of underground water ice detected by Odyssey and identified a mineral called calcium carbonate that suggested occasional presence of thawed water.

The lander also found soil chemistry with significant implications for life, and observed falling snow.

The mission’s biggest surprise was the discovery of perchlorate, an oxidizing chemical on Earth that is food for some microbes and potentially toxic for others.

“We found that the soil above the ice can act like a sponge, with perchlorate scavenging water from the atmosphere and holding on to it,” said Peter Smith, Phoenix principal investigator at the University of Arizona in Tucson.

“You can have a thin film layer of water capable of being a habitable environment. A micro-world at the scale of grains of soil—that’s where the action is.”

The perchlorate results are shaping subsequent astrobiology research, as scientists investigate the implications of its antifreeze properties and potential use as an energy source by microbes. Discovery of the ice in the uppermost soil by Odyssey pointed the way for Phoenix.

Artist's impression of the MRO spacecraft in orbit around Mars

Artist's impression of the MRO spacecraft in orbit around Mars.

Ice deposits

More recently, the MRO detected numerous ice deposits in middle latitudes at greater depth using radar and exposed on the surface by fresh impact craters.

“Ice-rich environments are an even bigger part of the planet than we thought,” Smith said. “Somewhere in that vast region there are going to be places that are more habitable than others.”

NASA’s MRO reached the planet in 2006 to begin a two-year primary science mission. Its data show Mars had diverse wet environments at many locations for differing durations during the planet’s history, and climate-change cycles persist into the present era.

The mission has returned more planetary data than all other Mars missions combined.

Odyssey has been orbiting Mars since 2001. The mission also has played important roles by supporting the twin Mars rovers Spirit and Opportunity.

Adapted from information issued by NASA / JPL-Caltech / University of Arizona / Texas A&M University.

Aussie tracking stations honoured

The Canberra Deep Space Communication Complex

The Canberra Deep Space Communication Complex at Tidbinbilla near Canberra, a part of NASA’s Deep Space Network.

  • NASA’s tracking stations in Australia
  • One current, two former
  • Made sites of Historic Aerospace Significance

The Canberra Deep Space Communication Complex (CDSCC) at Tidbinbilla and former tracking stations, Honeysuckle Creek and Orroral Valley, near Canberra, have been honoured by the American Institute of Aeronautics and Astronautics (AIAA) as sites of Historic Aerospace Significance.

Managed by CSIRO Astronomy and Space Science (CASS), the CDSCC host a plaque-unveiling ceremony at Tidbinbilla on Tuesday, May 25.

The three ACT tracking stations are being recognised as part of the AIAA’s global register of Historic Aerospace Sites which includes other important sites such as; the NASA Ames Research Centre, Moffett Field, California; Kitty Hawk, North Carolina.; and Tranquility Base on the Moon.

The former launch facility at Woomera, South Australia, is the only other AIAA Historic Aerospace Site in Australia.

This award recognises the significant role these three Australian tracking stations have played throughout the last 50 years, and the hundreds of men and women who have worked at each site in support of NASA’s manned and robotic space missions.

This recognition comes during the 50th anniversary of treaty-level cooperation between Australia and the US in space exploration.

“CSIRO is honoured to accept this designation on behalf of the dedicated alumni of the Honeysuckle Creek, Orroral Valley and Canberra Deep Space tracking stations,” said CDSCC Director Dr Miriam Baltuck.

“Australia’s role in the exploration of space has been ‘mission critical’ for over half a century, and we look forward with pleasure to continuing in that role in the decades to come.”

US Ambassador Jeffrey Bleich attended the ceremony and AIAA President David Thompson (founder and CEO of Orbital Sciences Corporation) formally designated the three ACT sites.

Adapted from information issued by CSIRO.

Wacky planets force a rethink

Diagram showing the orbits of three planets around the star Upsilon Andromedae A

Three Jupiter-type planets orbit the star Upsilon Andromedae A. Astronomers have found that the orbits of two of the planets are inclined by 30 degrees with respect to each other, something that hasn't been detected in any other planetary system.

  • Planets orbiting a distant star
  • Their orbits are wildly tilted to each other
  • Forcing a rethink of planetary evolution

The discovery of a planetary system “out of whack,” where the orbits of two planets are at a steep angle to each other, has been reported today by a team of astronomers led by Barbara McArthur of The University of Texas at Austin McDonald Observatory.

The surprising finding will affect concepts of how multi-planet systems evolve, and shows that some violent events can happen to disrupt planets’ orbits after a planetary system forms, say the researchers.

“The findings mean that future studies of exoplanetary systems will be more complicated. Astronomers can no longer assume all planets orbit their parent star in a single plane,” McArthur says. (An exoplanet is one that orbits a star other than the Sun.)

McArthur and her team used data from Hubble Space Telescope (HST), the giant Hobby-Eberly Telescope, and other ground-based telescopes combined with extensive computer modelling to unearth a landslide of information about the planetary system surrounding the nearby star Upsilon Andromedae (“Ups And”).

McArthur reported these findings in a press conference at the 216th meeting of the American Astronomical Society in Miami, along with her collaborator Fritz Benedict, also of McDonald Observatory, and team member Rory Barnes of the University of Washington. The work also will be published in the June 1 edition of the Astrophysical Journal.

A new angle on the theory

For just over a decade, astronomers have known that three Jupiter-type planets orbit the yellow-white dwarf star Upsilon Andromedae. Similar to our Sun, Upsilon Andromedae lies about 44 light-years away. It’s a bit younger, a bit more massive, and a bit brighter than the Sun.

Diagram showing a comparison between our Solar System and the Upsilon Andromedae A system.

A comparison of planetary orbits in our Solar System and the Upsilon Andromedae A system.

Much more startling, though, is the finding that not all planets orbit this star in the same plane. The orbits of planets “c” and “d” are inclined by 30 degrees with respect to each other.

This research marks the first time that the “mutual inclination” of two planets orbiting another star has been measured. And, the team has uncovered hints that a fourth planet, “e”, orbits the star much farther out.

“Most probably Upsilon Andromedae had the same formation process as our own Solar System, although there could have been differences in the late formation that seeded this divergent evolution,” McArthur said.

Until now the conventional wisdom has been that a big cloud of gas collapses down to form a star. Left over material forms a flattened cloud—known as a “disc”—surrounding the young star, and the formation of planets within it is a natural by-product. In our Solar System, there’s a telltale sign of that process because all of the eight major planets orbit in nearly the same plane.

“But now we have measured a significant angle between these planets that indicates this isn’t always the case,” says McArthur.

On the precipice of stability

So how did the two planets end up in such dissimilar orbits?

Possibilities include gravitational distortions during close encounters between planets in the system. Or it could have been a similar gravitational disruption caused by the parent star’s binary companion star, Upsilon Andromedae B.

The astronomers don’t know which scenario is correct, but they’ve found that the current orbital configuration is “right on the precipice of stability.”

“The planets pull on each other so strongly that they are almost able to throw each other out of the system,” says Barnes.

The team has also uncovered hints that a fourth, long-period planet may orbit beyond the three now known. There are only hints about that planet because it’s so far out, the signal it creates does not yet reveal the curvature of an orbit. Another missing piece of the puzzle is the inclination of the innermost planet b, which would require precision measurements 1,000 times greater than Hubble’s, a goal NASA’s planned Space Interferometry Mission (SIM) could attain.

The team’s Hubble data also confirmed Upsilon Andromedae’s status as a binary star. The companion star is a red dwarf less massive and much dimmer than the Sun.

We don’t have any idea what its orbit is,” Benedict said. “It could be very eccentric. Maybe it comes in very close every once in a while. It may take 10,000 years.”

Such a close pass by the primary star could gravitationally affect the orbits of its planets.

Adapted from information issued by McDonald Observatory, The University of Texas at Austin / STScI / NASA / ESA / A. Feild (STScI) / B. McArthur (The University of Texas at Austin, McDonald Observatory).

Bursting ‘bubbles’ give our Galaxy gas

The regions of our Galaxy the researchers studied

The regions of our Galaxy the researchers studied. More gas clouds were found in the region on the right than in the region on the left.

  • 650 Milky Way gas clouds studied
  • Each contains 700 times the mass of the Sun
  • Clouds might recycle gas in and out of the Galaxy

Like bubbles bursting on the surface of a glass of champagne, ‘bubbles’ in our Galaxy burst and leave ‘flecks’ of material in the form of clouds of hydrogen gas, researchers using CSIRO’s Parkes telescope have found.

Their study explains the origin of these clouds for the first time.

Swinburne University PhD student Alyson Ford (now at the University of Michigan) and her supervisors; Dr Naomi McClure-Griffiths (CSIRO Astronomy and Space Science) and Felix Lockman (US National Radio Astronomy Observatory), have made the first detailed observations of ‘halo’ gas clouds in our Galaxy.

Just as Earth has an atmosphere, the main starry disc of our Galaxy is surrounded by a thinner halo of stars, gas and ‘dark matter’.

The Parkes radio telescope

The Parkes radio telescope

The halo clouds skim the surface of our Galaxy, sitting 400 to 10,000 light-years outside the Galactic disc. They are big — an average-sized cloud contains hydrogen gas 700 times the mass of the Sun and is about 200 light-years across.

“We’re studying the clouds to understand what role they play in recycling material between the disc and halo,” Dr McClure-Griffiths said.

“The clouds can fall back down into the main body of the Galaxy, returning gas to it.”

Gas is “spritzing” up our Galaxy

The researchers studied about 650 clouds and found striking differences between them in different areas of the Galaxy. One part of the Galaxy had three times as many clouds as another next to it, and the clouds were twice as thick.

The region with lots of thick clouds is where lots of stars form, while the region with fewer clouds also forms fewer stars.

An image made with the Parkes radio telescope of some of the 'halo clouds' above the main body of our Galaxy.

An image made with the Parkes radio telescope of some of the 'halo clouds' above the main body of our Galaxy.

But the halo clouds aren’t found exactly where stars are forming right now. Instead, they seem to be linked to earlier star formation.

Massive stars grow old quickly. After a few million years they shed material into space as a ’wind‘ and then explode.

This violence creates bubbles in the gas in space, like the holes in a Swiss cheese.

“Stellar winds and explosions sweep up gas from the Galactic disc into the lower halo.

“We’ve found this churned-up gas is ‘spritzing’ the surface of the Galactic disc in the form of halo clouds.”

A star-forming region is active for less than a million years, but a super-bubble in the Galaxy takes 20 or 30 million years to form.

“Just as yeast takes a while to make wine bubbly, stars take a while to make the Galaxy bubbly,” Dr McClure-Griffiths said.

The halo clouds are distinct from a larger population of ‘high-velocity clouds’ that also sail outside the galaxy. The halo clouds move in tandem with the rotating Galaxy, while the high-velocity clouds scud along much faster.

This study is the first to accurately locate the halo clouds in relation to the main body of the Galaxy. Its findings were presented overnight at a news conference at a meeting of the American Astronomical Society in Miami, Florida.

Adapted from information issued by CSIRO / A Ford (U. Michigan), N. McClure-Griffiths (CSIRO Astronomy and Space Science) / NASA / JPL-Caltech / David McClenaghan.

Aussies and Kiwis forge cosmic connection

Antenna 1 of CSIRO's Australian SKA Pathfinder (ASKAP) telescope in Western Australia.

Antenna 1 of CSIRO's Australian SKA Pathfinder (ASKAP) telescope in Western Australia.

  • Six dishes linked across Australia / New Zealand
  • Formed one virtual telescope 5,500km wide
  • Australia bidding for world’s biggest radio telescope

Six radio telescopes across Australia and New Zealand have joined forces to act as one giant telescope, linking up over a distance of 5,500km for the first time.

The link-up was a collaboration between CSIRO’s Astronomy and Space Science division, the International Centre for Radio Astronomy Research at Curtin University of Technology in Western Australia, and AUT University in New Zealand.

The linked telescope will make images 10 times more detailed than those of the Hubble Space Telescope and has already been used to peer into the heart of a galaxy called Centaurus A.

Showing Australia and New Zealand can link telescopes this way strengthens the two countries’ joint bid to host the international Square Kilometre Array (SKA) telescope.

“The SKA is a truly mega-sized science project with its global reach, scale and ambition, akin to the Large Hadron Collider in Europe,” said CSIRO SKA Director Dr Brian Boyle.

“This successful linking of antennae shows Australia and New Zealand’s commitment to next-generation astronomical research and how seriously we are taking the SKA bid.”

The new 12-m dish near Warkworth in the North Island of New Zealand.

The new 12-m dish near Warkworth in the North Island of New Zealand.

Aiming for world’s biggest radio telescope

The giant $2.5 billion SKA will have several thousand antennae, up to 5,500km apart, working together as one telescope.

Fifty times more sensitive than today’s radio telescopes, the SKA will scan the cosmos for black holes, star formation and magnetic fields in space.

Australia and New Zealand are one of two regions shortlisted to host the SKA. The other is Southern Africa. A decision is expected in 2012.

The newcomers to the Australasian telescope team are the New Zealand dish, near Warkworth in the hills of the North Island, and a new CSIRO dish in Western Australia’s red dirt country, inland from Geraldton.

The new CSIRO dish is the first antenna of the Australian SKA Pathfinder (ASKAP) radio telescope.

The Warkworth dish is operated by AUT and is the first functioning research-quality radio telescope in New Zealand.

Data from New Zealand radio telescope were transferred from Warkworth directly to Australia using recently established 1 Gb per second connectivity via the Kiwi Advanced Research and Education Network (KAREN).

“The linking of the Warkworth antenna is a milestone for New Zealand science,” said the Director of the Institute for Radio Astronomy and Space Research at AUT, Professor Sergei Gulyaev.

Zooming in to the heart of galaxy Centaurus A

Zooming in to the heart of galaxy Centaurus A, 14 million light-years away. This composite image shows the entire galaxy, as imaged by CSIRO radio telescopes; radio emission from a central part of the galaxy, imaged by a US radio telescope; and the innermost part of the galaxy, imaged by the new network of Australian & NZ radio telescopes.

“It shows that Australia and New Zealand can achieve the SKA’s ambitious science goals.”

The other telescopes used in the link-up were three CSIRO facilities in New South Wales and a University of Tasmania dish near Hobart, Tasmania.

Amazing detail seen

One of the linked telescope’s first projects has been to study the heart of a galaxy called Centaurus A.

Lurking there is a black hole that shoots out jets of radio-emitting particles at close to the speed of light.

Observing for the galaxy for 10 hours, the telescopes took enough data to fill a stack of DVDs in their cases as high as a nine-storey building.

The International Centre for Radio Astronomy Research at Curtin University of Technology provided the equipment for recording the data and also analysed the data to make an image.

The resolution of the new image is 100,000 times higher than that of a ground-breaking radio image made by CSIRO last year, which is itself the most detailed image ever made of the whole galaxy.

“Centaurus A is 14 million light-years away,” said Curtin University’s Professor Steven Tingay, a radio astronomy expert. “We’re zooming in on the black hole at the heart of this galaxy, to learn about how these systems work.

“Making the new image has been like photographing a pin head from 20km away.”

Adapted from information issued by CSIRO.

Centaurus A image credit: Whole galaxy: I. Feain, T. Cornwell & R. Ekers (CSIRO/ATNF); ATCA northern middle lobe pointing courtesy R. Morganti (ASTRON); Parkes data courtesy N. Junkes (MPIfR). Inner radio lobes:  NRAO / AUI / NSF. Core: S. Tingay (ICRAR) / ICRAR, CSIRO and AUT. ASKAP

ASKAP image credit: P. Dawson

Warkworth antenna image credit: Tim Natusch, AUT

Space food: Try a strawberry

Purdue University's Gioia Massa, Cary Mitchell and Judith Santini found that a particular type of strawberry seems to meet NASA guidelines for foods that could be grown in space.

Purdue University's Gioia Massa, Cary Mitchell and Judith Santini found that a particular type of strawberry seems to meet NASA guidelines for foods that could be grown in space.

  • Strawberries tested for growing in space
  • Performed well in the laboratory
  • Could be used in “salad machines”

Astronauts could one day tend their own crops on long space missions, and Purdue University researchers have found a healthy candidate to help satisfy a sweet tooth—a strawberry that requires little maintenance and energy.

Cary Mitchell, professor of horticulture, and Gioia Massa, a horticulture research scientist, tested several cultivars of strawberries and found one variety, named Seascape, which seems to meet the requirements for becoming a space crop.

“What we’re trying to do is grow our plants and minimise all of our inputs,” Massa said. “We can grow these strawberries under shorter photoperiods than we thought and still get pretty much the same amount of yield.”

Cosmonaut Oleg V. Kotov pictured near "fresh" fruit floating freely in the International Space Station

Cosmonaut Oleg V. Kotov pictured near "fresh" fruit floating freely in the International Space Station. The fruit had been brought up on a supply mission.

Seascape strawberries are day-neutral, meaning they aren’t sensitive to the length of available daylight to flower. Seascape was tested with as much as 20 hours of daylight and as little as 10 hours. While there were fewer strawberries with less light, each berry was larger and the volume of the yields was statistically the same.

“I was astounded that even with a day-neutral cultivar we were able to get basically the same amount of fruit with half the light,” Mitchell said.

The perfect fruit for space missions

The findings, which were reported online early in the journal Advances in Space Research, showed that the Seascape strawberry cultivar is a good candidate for a space crop because it meets several guidelines set by NASA.

Strawberry plants are relatively small, meeting mass and volume restrictions. Since Seascape provides fewer, but larger, berries under short days, there is less labour required of crewmembers who would have to pollinate and harvest the plants by hand. Needing less light cuts down energy requirements not only for lamps, but also for systems that would have to remove heat created by those lights.

“We’re trying to think of the whole system—growing food, preparing it and getting rid of the waste,” Massa said. “Strawberries are easy to prepare and there’s little waste.”

Astronaut Sandra Magnus poses with food that she prepared at the galley in the International Space Station.

Astronaut Sandra Magnus poses with food that she prepared at the galley in the International Space Station.

Seascape also had less cycling, meaning it steadily supplied fruit throughout the test period. Massa said the plants kept producing fruit for about six months after starting to flower.

Space-based “salad machines”

Mitchell said the earliest space crops will likely be part of a “salad machine,” a small growth unit that will provide fresh produce that can supplement traditional space meals. Crops being considered include lettuces, radishes and tomatoes. Strawberries may be the only sweet fruit being considered, he said.

“The idea is to supplement the human diet with something people can look forward to,” Mitchell said. “Fresh berries can certainly do that.”

Judith Santini, a research statistical analyst in Purdue’s Department of Agronomy, was responsible for data analysis from the tests.

Mitchell and Massa said they next plan to test Seascape strawberries using LED lighting, hydroponics and different temperature ranges. NASA funded their work.

Adapted from information issued by Purdue University / Purdue Agricultural Communication / Tom Campbell.

Spiral galaxy M83

Image of the nearby galaxy Messier 83

This image of the nearby galaxy Messier 83 was taken in the infrared part of the spectrum with the HAWK-I instrument on ESO’s Very Large Telescope, revealing vast numbers of stars within the galaxy.

  • 15 million light-years away
  • 40 percent the size of the Milky Way
  • Home to 6 recently spotted exploding stars

The European Southern Observatory (ESO) has released a beautiful image of the nearby galaxy Messier 83 taken by the HAWK-I instrument on ESO’s Very Large Telescope (VLT) at the Paranal Observatory in Chile.

The picture shows the galaxy in infrared light and demonstrates the impressive power of the camera to create one of the sharpest and most detailed pictures of Messier 83 ever taken from the ground.

Messier 83 is about 15 million light-years away. It is over 40,000 light-years wide, only 40 percent the size of the Milky Way, but in many ways is quite similar to our home galaxy, both in its spiral shape and the presence of a bar of stars across its centre.

The galaxy is famous among astronomers for its many supernovae: vast explosions that end the lives of some stars. Over the last century, six supernovae have been spotted in Messier 83 — a record number that is matched by only one other galaxy.

Comparison of the view of the galaxy Messier 83 in infrared and visible light.

Comparison of the view of the galaxy Messier 83 at infrared light wavelengths (left) and at visible light wavelengths (right). In the infrared, the dust that obscures many stars becomes nearly transparent, making the spiral arms seem less dramatic, but revealing a whole host of new stars that are otherwise invisible.

Even without supernovae, Messier 83 is one of the brightest nearby galaxies, visible using just binoculars.

When viewed in infrared light by HAWK-I, most of the obscuring dust that hides much of Messier 83 becomes transparent. The brightly lit gas around hot young stars in the spiral arms is also less prominent in infrared pictures. As a result much more of the structure of the galaxy and the vast hordes of its constituent stars can be seen.

This clear view is important for astronomers looking for clusters of young stars, especially those hidden in dusty regions of the galaxy. Studying such star clusters was one of the main scientific goals of these observations. The acute vision of HAWK-I reveals far more stars within the galaxy.

Adapted from information issued by ESO / M. Gieles / Mischa Schirmer.

The windy Leeward Islands

A NASA Terra satellite image of the Leeward Islands in the Caribbean Sea.

A NASA Terra satellite image of the Leeward Islands in the Caribbean Sea.

  • Located in the Caribbean Sea
  • Includes the Virgin Islands, Montserrat & Antigua

This image, captured by NASA’s Terra satellite on March 25, 2010, shows the Leeward Islands, part of the Lesser Antilles chain in the West Indies.

The Leewards are located in the Caribbean Sea, where the Sea meets the Atlantic Ocean. The Leeward Islands are so called because they are down wind (or leeward of) the Windward Islands. The prevailing winds in this region blow from the east, and hit the Windward Islands first.

The Virgin Islands, Montserrat, Antigua, and Saint Kitts are some of the more familiar islands that are part of the Leewards. Saint Kitts is the long oval island on the left side of this image. Nevis is to its southeast. Antigua is to the east of Nevis—it is the largest of the Leeward Islands.

Adapted from information issued by Jeff Schmaltz, MODIS Land Rapid Response Team, NASA GSFC.