StarStuff

Just a reminder…
StarStuff episode 627 is now out
Listen to it on the best ABC radio stations across Australia.
On Science 360 Radio in the United States.
On line as audio on demand and as a podcast at:
http://www.abc.net.au/science/starstuff
or as a free download from iTunes

This week’s show…..

Record setting Gamma Ray Burst shocks astronomers
A powerful eruption of gamma rays from a dying star in a distant galaxy has stunned astronomers around the world. The gamma-ray burst produced the highest-energy light ever detected from such an event and signalled the birth of a black hole

Earth’s core moves to a different beat
A new study claims Planet Earth isn’t all spinning at the same rate. The planet’s inner-core rotation varies in comparison to its overlying mantle and crust.

Earth and Moon’s water had common origin
A new study has found that the water on the Moon came from the same source as the Earth’s water. The discovery implies some of Earth’s water was transferred to the Moon at the time of its formation.

Gas clouds solve cosmic mystery
In a dark, starless patch of intergalactic space, astronomers have discovered a never-before-seen cluster of hydrogen clouds strewn between two nearby neighbouring galaxies, Andromeda (M31) and Triangulum (M33). The research is providing new clues about galactic evolution.

Europe launches its new rocket
The European Space Agency’s new lightweight Vega launch vehicle has successfully blasted into orbit on its first mission since its maiden flight in February last year. Carrying two small Earth-observation satellites and a microsatellite, the 30 metre tall four stage rocket blasted off from the Kourou space port in French Guiana following a two day delay due to bad weather.

Skywatch May
The Eta Aquarids Meteor shower is just one of the highlights we check out on Skywatch in the night skies of May.

StarStuff is broadcast weekly on the best ABC Radio stations in Australia,
On the National Science Foundation’s Science 360 Radio across the United States.
As audio on demand and as a free podcast at….
http://www.abc.net.au/science/starstuff

NINE-YEAR-OLD MARS ROVER PASSES 40-YEAR-OLD RECORD

While Apollo 17 astronauts Eugene Cernan and Harrison Schmitt visited Earth’s Moon for three days in December 1972, they drove their mission’s Lunar Roving Vehicle 19.3 nautical miles (22.21 statute miles or 35.74 kilometers). That was the farthest total distance for any NASA vehicle driving on a world other than Earth until yesterday.

The team operating NASA’s Mars Exploration Rover Opportunity received confirmation in a transmission from Mars today that the rover drove 263 feet (80 meters) on Thursday, bringing Opportunity’s total odometry since landing on Mars in January 2004 to 22.22 statute miles (35.76 kilometers).

Cernan discussed this prospect a few days ago with Opportunity team member Jim Rice of NASA Goddard Space Flight Center, Greenbelt, Md. The Apollo 17 astronaut said, “The record we established with a roving vehicle was made to be broken, and I’m excited and proud to be able to pass the torch to Opportunity.”

The international record for driving distance on another world is still held by the Soviet Union’s remote-controlled Lunokhod 2 rover, which traveled 23 miles (37 kilometers) on the surface of Earth’s Moon in 1973.

Opportunity began a multi-week trek this week from an area where it has been working since mid-2011, the “Cape York” segment of the rim of Endeavor Crater, to an area about 1.4 miles (2.2 kilometers) away, “Solander Point.”

7 Notes

NASA Helps Pinpoint Glaciers’ Role in Sea Level Rise

A new study of glaciers worldwide using observations from two NASA satellites has helped resolve differences in estimates of how fast glaciers are disappearing and contributing to sea level rise.

The new research found glaciers outside of the Greenland and Antarctic ice sheets, repositories of 1 percent of all land ice, lost an average of 571 trillion pounds (259 trillion kilograms) of mass every year during the six-year study period, making the ocean rise 0.03 inches (0.7 millimeters) per year. This is equal to about 30 percent of the total observed global sea level rise during the same period and matches the combined contribution to sea level from the Greenland and Antarctica ice sheets.

The study compares traditional ground measurements to satellite data from NASA’s Ice, Cloud, and Land Elevation Satellite (ICESat) and Gravity Recovery and Climate Experiment (GRACE) missions to estimate ice loss for glaciers in all regions of the planet. The study period spans 2003 to 2009, the years when the two missions overlapped.

“For the first time, we have been able to very precisely constrain how much these glaciers as a whole are contributing to sea level rise,” said Alex Gardner, Earth scientist at Clark University in Worcester, Mass., and lead author of the study. “These smaller ice bodies are currently losing about as much mass as the ice sheets.”

The study was published Thursday in the journal Science.

ICESat, which stopped operating in 2009, measured glacier change through laser altimetry, which bounces lasers pulses off the ice surface to inform the satellite of changes in the height of the ice cover. ICESat’s successor, ICESat-2, is scheduled to launch in 2016. GRACE, still operational, detects variations in Earth’s gravity field resulting from changes in the planet’s mass distribution, including ice displacements.

The new research found all glacial regions lost mass from 2003 to 2009, with the biggest ice losses occurring in Arctic Canada, Alaska, coastal Greenland, the southern Andes and the Himalayas. In contrast, Antarctica’s peripheral glaciers — small ice bodies not connected to the main ice sheet — contributed little to sea level rise during that period. The study builds on a 2012 study using only GRACE data that also found glacier ice loss was less than estimates derived from ground-based measurements.

Current estimates predict all the glaciers in the world contain enough water to raise sea level by as much as 24 inches (about 60 centimeters). In comparison, the entire Greenland ice sheet has the potential to contribute about 20 feet (about 6 meters) to sea level rise and the Antarctic ice sheet just less than 200 feet (about 60 meters).

“Because the global glacier ice mass is relatively small in comparison with the huge ice sheets covering Greenland and Antarctica, people tend to not worry about it,” said study co-author Tad Pfeffer, a glaciologist at the University of Colorado in Boulder. “But it’s like a little bucket with a huge hole in the bottom: it may not last for very long, just a century or two, but while there’s ice in those glaciers, it’s a major contributor to sea level rise.”

To make ground-based estimates of glacier mass changes, glaciologists perform on-site measurements along a line from a glacier’s summit to its edge. Scientists extrapolate these measurements to the entire glacier area and carry them out for several years to estimate the glacier’s overall mass change over time. While this type of measurement does well for small, individual glaciers, it tends to overestimate ice loss when the findings are extrapolated to larger regions, such as entire mountain ranges.

“Ground observations often can only be collected for the more accessible glaciers, where it turns out thinning is occurring more rapidly than the regional averages,” Gardner said. “That means when those measurements are used to estimate the mass change of the entire region, you end up with regional losses that are too great.”

GRACE does not have fine enough resolution and ICESat does not have sufficient sampling density to study small glaciers, but the two satellites’ estimates of mass change for large glaciered regions agree well, the study concluded.

“We now have a lot more data for the glacier-covered regions because of GRACE and ICESat,” said Gardner. “Without having these independent observations, there was no way to tell that the ground observations were biased.”

The research involved 16 researchers from 10 countries, with major contributions from Clark University, the University of Michigan in Ann Arbor, Scripps Institution of Oceanography in San Diego, Trent University in Ontario, the University of Colorado at Boulder and the University of Alaska Fairbanks. For images of glaciers studied for this paper, visit: http://go.nasa.gov/15JSmzl .

GRACE is a joint mission with the German Aerospace Center and the German Research Center for Geosciences, in partnership with the University of Texas at Austin. For more about GRACE, visit: http://www.nasa.gov/grace and http://www.csr.utexas.edu/grace . For information about NASA and agency programs, visit: http://www.nasa.gov . NASA’s Jet Propulsion Laboratory, Pasadena, Calif., developed the GRACE spacecraft and manages the mission for NASA’s Science Mission Directorate, Washington. The California Institute of Technology in Pasadena manages JPL for NASA.

IMAGE…The Aletschglacier in Switzerland is the largest valley glacier in the Alps. Its volume loss since the middle of the 19th century is well visible from the trimlines to the right of the image. Credit: Frank Paul, University of Zurich

1 Notes

NASA’s Asteroid Sample Return Mission Moves into Development WASHINGTON — NASA’s first mission to sample an asteroid is moving ahead into development and testing in preparation for its launch in 2016.

The Origins-Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) passed a confirmation review Wednesday called Key Decision Point (KDP)-C. NASA officials reviewed a series of detailed project assessments and authorized the spacecraft’s continuation into the development phase.

OSIRIS-REx will rendezvous with the asteroid Bennu in 2018 and return a sample of it to Earth in 2023.

“Successfully passing KDP-C is a major milestone for the project,” said Mike Donnelly, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Md. “This means NASA believes we have an executable plan to return a sample from Bennu. It now falls on the project and its development team members to execute that plan.”

Bennu could hold clues to the origin of the solar system. OSIRIS-REx will map the asteroid’s global properties, measure non-gravitational forces and provide observations that can be compared with data obtained by telescope observations from Earth. OSIRIS-REx will collect a minimum of 2 ounces (60 grams) of surface material.

“The entire OSIRIS-REx team has worked very hard to get to this point,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson. “We have a long way to go before we arrive at Bennu , but I have every confidence when we do, we will have built a supremely capable system to return a sample of this primitive asteroid.”

The mission will be a vital part of NASA’s plans to find, study, capture and relocate an asteroid for exploration by astronauts. NASA recently announced an asteroid initiative proposing a strategy to leverage human and robotic activities for the first human mission to an asteroid while also accelerating efforts to improve detection and characterization of asteroids.

NASA’s Goddard Space Flight Center in Greenbelt, Md. will provide overall mission management, systems engineering and safety and mission assurance. The University of Arizona in Tucson is the principal investigator institution. Lockheed Martin Space Systems of Denver will build the spacecraft. OSIRIS-REx is the third mission in NASA’s New Frontiers Program. NASA’s Marshall Space Flight Center in Huntsville, Ala., manages New Frontiers for NASA’s Science Mission Directorate in Washington.

IMAGE….Asteroid-Sampling Mission Moves into Development
NASA’s first mission to sample an asteroid is moving ahead into development and testing in preparation for its launch in 2016.

Sierra Nevada Corporation Dream Chaser Testing Begins at NASA Dryden, Langley

Sierra Nevada Corporation’s (SNC) Space Systems Dream Chaser flight vehicle arrived at NASA’s Dryden Flight Research Center in Edwards, Calif., Wednesday to begin tests of its flight and runway landing systems.

The tests are part of pre-negotiated, paid-for-performance milestones with NASA’s Commercial Crew Program (CCP), which is facilitating U.S.-led companies’ development of spacecraft and rockets that can launch from American soil. The overall goal of CCP is to achieve safe, reliable and cost-effective U.S. human access to and from the International Space Station and low-Earth orbit.

Tests at Dryden will include tow, captive-carry and free-flight tests of the Dream Chaser. A truck will tow the craft down a runway to validate performance of the nose strut, brakes and tires. The captive-carry flights will further examine the loads it will encounter during flight as it is carried by an Erickson Skycrane helicopter. The free flight later this year will test Dream Chaser’s aerodynamics through landing.

Meanwhile, on the east coast, several NASA astronauts will be at the agency’s Langley Research Center in Hampton, Va., this week to fly simulations of a Dream Chaser approach and landing to help evaluate the spacecraft’s subsonic handling. The test will measure how well the spacecraft would handle in a number of different atmospheric conditions and assess its guidance and navigation performance.

“Unique public-private partnerships like the one between NASA and Sierra Nevada Corporation are creating an industry capable of building the next generation of rockets and spacecraft that will carry U.S. astronauts to the scientific proving ground of low-Earth orbit,” said William Gerstenmaier, NASA’s associate administrator for human exploration and operations in Washington. “NASA centers around the country paved the way for 50 years of American human spaceflight, and they’re actively working with our partners to test innovative commercial space systems that will continue to ensure American leadership in exploration and discovery.”

The Dream Chaser Space System is based on Langley’s Horizontal Lander HL-20 lifting body design concept. The design builds on years of analysis and wind tunnel testing by Langley engineers during the 1980s and 1990s. Langley and SNC joined forces six years ago to update the HL-20 design in the Dream Chaser orbital crew vehicle. In those years SNC has worked with the center to refine the spacecraft design. SNC will continue to test models in Langley wind tunnels. Langley researchers also helped develop a cockpit simulator at SNC’s facility in Louisville, Colo., and the flight simulations being assessed at the center.

NASA is partnered with SNC, Space Exploration Technologies (SpaceX) and The Boeing Company to meet CCP milestones for integrated crew transportation systems under the Commercial Crew Integrated Capability (CCiCap) initiative. Advances made by these companies under their funded Space Act Agreements ultimately are intended to lead to the availability of commercial human spaceflight services for government and commercial companies.

While NASA works with U.S. industry partners to develop commercial spaceflight capabilities, the agency also is developing the Orion spacecraft and the Space Launch System (SLS), a crew capsule and heavy-lift rocket to provide an entirely new capability for human exploration. Designed to be flexible for launching spacecraft for crew and cargo missions, SLS and Orion will expand human presence beyond low-Earth orbit and enable new missions of exploration in the solar system

4 Notes

NASA’S ASTEROID SAMPLE RETURN MISSION MOVES INTO DEVELOPMENT

NASA’s first mission to sample an asteroid is moving ahead into development and testing in preparation for its launch in 2016.

The Origins-Spectral Interpretation Resource Identification Security Regolith Explorer (OSIRIS-REx) passed a confirmation review Wednesday called Key Decision Point (KDP)-C. NASA officials reviewed a series of detailed project assessments and authorized the spacecraft’s continuation into the development phase.

OSIRIS-REx will rendezvous with the asteroid Bennu in 2018 and return a sample of it to Earth in 2023.

“Successfully passing KDP-C is a major milestone for the project,” said Mike Donnelly, OSIRIS-REx project manager at NASA’s Goddard Space Flight Center in Greenbelt, Md. “This means NASA believes we have an executable plan to return a sample from Bennu. It now falls on the project and its development team members to execute that plan.”

Bennu could hold clues to the origin of the solar system. OSIRIS-REx will map the asteroid’s global properties, measure non-gravitational forces and provide observations that can be compared with data obtained by telescope observations from Earth. OSIRIS-REx will collect a minimum of 2 ounces (60 grams) of surface material.

“The entire OSIRIS-REx team has worked very hard to get to this point,” said Dante Lauretta, OSIRIS-REx principal investigator at the University of Arizona in Tucson. “We have a long way to go before we arrive at Bennu , but I have every confidence when we do, we will have built a supremely capable system to return a sample of this primitive asteroid.”

The mission will be a vital part of NASA’s plans to find, study, capture and relocate an asteroid for exploration by astronauts. NASA recently announced an asteroid initiative proposing a strategy to leverage human and robotic activities for the first human mission to an asteroid while also accelerating efforts to improve detection and characterization of asteroids.

STANFORD PROFESSOR AND FORMER NASA OFFICIAL
EXPLAINS HOW NASA MIGHT REVIVE THE KEPLER SPACE TELESCOPE

** Synopsis: Scott Hubbard, a consulting professor of aeronautics and astronautics, helped guide the Kepler mission when he served as director of NASA Ames Research Center. He explains how NASA might bring the planet-hunting spacecraft back online. **

NASA officials announced Wednesday, May 15, that the Kepler space telescope — the agency’s primary instrument for detecting planets beyond our solar system — had suffered a critical failure and could soon be shut down permanently.

Scott Hubbard, a consulting professor of aeronautics and astronautics at Stanford’s School of Engineering, served as director of NASA Ames Research Center during much of the building phase of the Kepler space telescope. He also worked on the project alongside William Borucki, the Kepler science principal investigator at Ames and the driving force behind the effort, for the decades leading up to formal approval of the mission.

The Kepler spacecraft’s photo-detector array registers more than 100,000 stars at a time, Hubbard said, and in order to detect exoplanets (planets orbiting stars outside our solar system), the telescope must remain extremely steady so that the stars do not wander across the optics. A series of four gyroscope-like reaction wheels whir within the telescope to hold its gaze. At least three must be functioning to keep Kepler stable. One failed about a year ago and was shut off, and NASA scientists announced Wednesday, May 15, that a second wheel was no longer operating and that Kepler had paused operations.

In a conversation with Stanford News Service, Hubbard explained the possible ways that NASA could bring the spacecraft back online, and what planet hunters will do next if that’s not possible.

Q: How big of a loss will it be if the Kepler space telescope can’t be repaired?

A: The science returns of the Kepler mission have been staggering and have changed our view of the universe, in that we now think there are planets just about everywhere.

It will be very sad if it can’t go on any longer, but the taxpayers did get their money’s worth. Kepler has, so far, detected more than 2,700 candidate exoplanets orbiting distant stars, including many Earth-size planets that are within their star’s habitable zone, where water could exist in liquid form.

Kepler has done what the program managers said it would do, and that is to give us an inventory of extrasolar planets. It completed its primary observation phase, and had entered its extended science phase. We’re already in the gravy train period — there’s still a year and a half’s worth of data in the pipeline that scientists will analyze to identify other candidate planets, and there will continue to be Kepler science discoveries for quite some time.

Q: How might NASA engineers go about getting Kepler functional again?

A: There are two possible ways to salvage the spacecraft that I’m aware of. One is that they could try turning back on the reaction wheel that they shut off a year ago. It was putting metal on metal, and the friction was interfering with its operation, so you could see if the lubricant that is in there, having sat quietly, has redistributed itself, and maybe it will work.

The other scheme, and this has never been tried, involves using thrusters and the solar pressure exerted on the solar panels to try and act as a third reaction wheel and provide additional pointing stability. I haven’t investigated it, but my impression is that it would require sending a lot more operational commands to the spacecraft.

Q: If neither of these options works, Kepler is still an amazing space instrument. Could it conduct other types of experiments?

A: People have asked about using it to find near-Earth objects, or asteroids. Kepler carries a photometer, not a camera, that looks at the brightness of stars, and so its optics deliberately defocus light from stars to create a nice spread of light on the detector, which is not ideal for spotting asteroids.

Whether or not it could function as a detector for asteroids is something that would have to be studied, but since it wasn’t built as a camera, I would say that I’m skeptical. That said, certainly between Ames Research Center and the Jet Propulsion Laboratory, they’ve got the best people in the world working on it.

Q: What’s next for exoplanet hunters?

A: As I said earlier, there is still a year and a half’s worth of data in the pipeline to analyze to identify candidate planets, so there are still discoveries to be made.

It’s important to make clear, though, that in the original queue of missions aimed at finding life elsewhere, a mission like Kepler was a survey mission to establish the statistical frequency of whether these planets are rare or common. It lived the length of its prime mission, and was extremely successful during that time at achieving this goal. It has paved the way for additional missions, such as TESS — Transiting Exoplanet Survey Satellite — and TPF — Terrestrial Planet Finder — which will continue the search for Earth-like exoplanets in the near future.

OUTH AFRICA’S NEW RADIO TELESCOPE REVEALS
GIANT OUTBURSTS FROM BINARY STAR SYSTEM

The first scientific paper based on observations performed with South Africa’s new KAT-7 radio telescope has been accepted for publication by the prestigious journal Monthly Notices of the Royal Astronomy Society.

“This is a significant milestone for South Africa’s SKA project, proving that our engineers are able to deliver a cutting-edge scientific instrument, and that our scientists are able to use it for frontier science,” says Derek Hanekom, South Africa’s Minister of Science and Technology. “It bodes well for the delivery of our 64-dish MeerKAT telescope, currently under construction in the Karoo, and for our ability to play a key role in building and commissioning thousands of SKA antennas over the next ten years.”

Using the new KAT-7 telescope in the Karoo and the existing 26 m radio telescope at the Hartebeesthoek Radio Astronomy Observatory (HartRAO), South African and international astronomers have observed a neutron star system known as Circinus X-1 as it fires energetic matter from its core in extensive, compact jets that flare brightly. The details of the flares are visible only in radio waves.

Circinus X-1 is an X-ray binary (or two-star system) where one of the companion stars is a high-density, compact neutron star (a neutron star is an extremely dense and compact remnant of an exploded star, only about 20 km in diameter). The two stars orbit each other every 16.5 days in an elliptical orbit. When the two stars are at their closest, the gravity of the dense neutron star pulls material from the companion star. A powerful jet of material then blasts out from the system.

During the time that KAT-7 observed Circinus X-1 (13 December 2011 to 16 January 2012), the system flared twice at levels among the highest observed in recent years. KAT-7 was able to catch both these flares and follow them as they progressed. This is the first time that the system has been observed in such detail during multiple flare cycles.

“One way of explaining what is happening is that the compact neutron star gobbles up part of its companion star and then fires much of this matter back out again,” explains Dr. Richard Armstrong, an SKA Fellow at the University of Cape Town and lead author of the paper reporting these results. “The dramatic radio flares happen when the matter Circinus X-1 has violently ejected slows down as it smashes into the surrounding gas.”

At the same time Circinus X-1 was being observed at HartRAO at two higher frequencies as part of a long-term study of this object. “The flares are much stronger at the higher frequencies and by combining the three sets of measurements, we could study how each flare evolved as time progressed and investigate details of the turbulent interactions of the jet,” adds HartRAO Emeritus Astronomer Dr. George Nicolson, a pioneer of radio astronomy in South Africa.

“These types of observations help us to understand how matter is accreted onto extremely dense systems, such as neutron stars and black holes,” Armstrong says. “They also shed light on how neutron stars are able to generate these powerful outflows and associated radio bursts.”

“KAT-7 was really intended as an engineering test bed to refine the design and systems for the MeerKAT telescope that we are working on now, but we are absolutely delighted that it has turned out to be a top quality science instrument, capable of producing significant science,” says Professor Justin Jonas of Rhodes University, who is also the associate director for science and engineering at the SKA South Africa Project Office. “We plan to continue using KAT-7 to do science until at least 2015 when part of the 64-dish MeerKAT telescope will become available to researchers.”

Scientists from the SKA Project in South Africa and local and international universities worked together on both the observations and the analysis. This work is part of the development for the ThunderKAT project on MeerKAT, which will find many more of these types of systems in the galaxy, and search for new types of radio systems that change rapidly with time.

The two leaders of the ThunderKAT project, Professor Rob Fender of the University of Southampton and Professor Patrick Woudt of the University of Cape Town, explain that the ThunderKAT project searches for all types of radio bursts and flashes in KAT-7 and MeerKAT data on timescales from seconds to years. Finding and studying the systems that produce these outbursts will allow us to test the extremes of physics, and are beyond anything achievable in any laboratory on Earth. “These systems provide a unique glimpse of the laws of physics operating in extraordinary regimes,” Woudt says, “and nearly all such events are associated with transient radio emission.”

The ThunderKAT project is already well under way, and besides these observations, has made targeted observations of other exciting systems including the flaring black hole candidate Swift J1745.1-2624, the diffuse radio structure around the black-hole binary GRS 1915+105, as well as a system that is very close to our Sun, the brown dwarf binary WISE 1049-5319.

TOP IMAGE….An artist’s impression of the Circinus X-1 system showing the binary (double) star system. Two stars orbit each other every 16.5 days in an elliptical orbit. The small white sphere is the neutron star - an extremely dense and compact remnant of an exploded star, only about 20 km in diameter. The red sphere is an ordinary star - the companion star in this system. When the two stars are at their closest, the neutron star pulls material from its companion star. An accretion disk (the blue disk) forms around the neutron star, containing the matter that is sucked from the ordinary star. Powerful jets of material (the orange rays) then blast out from the neutron star at close to the speed of light, causing powerful flares in radio frequencies.

LOWER IMAGE….Circinus X-1: The bright region in the middle of this KAT-7 radio image, observed at 1 822 MHz (with 256 MHz bandwidth), shows Circinus X-1 during the flare. Download

First new Galileo satellite arrives at ESA for space testing

The first satellite of Galileo’s next phase has arrived at ESA’s technical heart in the Netherlands for a rigorous set of tests to check its readiness for launch.

This first Galileo Full Operational Capability – FOC – satellite is functionally identical to the first four Galileo In-Orbit Validation satellites already in orbit, the operational nucleus of the full Galileo constellation, but has been built by a separate industrial team.

Like all the other 21 FOC satellites so far procured by ESA, the satellite’s prime contractor is OHB in Bremen, Germany and the navigation payload was produced by Surrey Satellite Technology Ltd in Guildford, UK.

This first FOC satellite arrived by road at ESTEC’s Test Centre in Noordwijk, the Netherlands, on 15 May to undergo a series of tests simulating different aspects of launch and space environment. The comprehensive test programme will validate the new design and all the satellites to follow.

A unique facility for Europe, ESA’s test centre has all the facilities needed to validate a satellite for launch under a single roof.

Thermal vacuum testing will simulate the temperature extremes the satellites must endure in the airlessness of space throughout their 12-year working lifetimes. Without any moderating atmosphere, temperatures can shift hundreds of degrees from sunlight to shadow.

Other activities on the schedule include shaker and acoustic noise testing – simulating the vibration and noise of launch – as well as electromagnetic compatibility and antenna testing, placing the satellite in chambers shielded from all external radio signals to reproduce infinite space and check that its various antennas and electrical systems are interoperable without harmful interference.

Each satellite will offer the full range of Galileo positioning, navigation and timing services, plus search and rescue message relays, their accuracy ensured by onboard atomic clocks kept synchronised by a worldwide ground network.

“The Galileo FOC satellites provide the same capabilities as the previous IOV satellites, but with improved performance, such as higher transmit power,” explains Giuliano Gatti, the Head of the Galileo Space Segment Procurement Office. “They are to all intents a new design that requires a full checkout before getting the green light for launch.

“By fully validating this satellite, the second flight model due to follow it here at beginning of June, and the third one due to arrive in ESTEC at middle of July, we gain full knowledge of their characteristics, and the further satellites in the series will require less rigorous functional testing.”

2 Notes

Next destination: space

ESA astronaut Luca Parmitano left for Baikonur, Kazakhstan today, his last stop before heading to the International Space Station on 28 May.

His launch on a Soyuz rocket will be the culmination of more than two years of preparation that has seen Luca training in Russia, Canada, Japan, Europe and the US at facilities of the Station partners.

Luca and his crewmates, cosmonaut commander Fyodor Yurchikhin and NASA astronaut Karen Nyberg, spent the last few weeks in Moscow, Russia passing their final exams for flying the Soyuz spacecraft. They received their official tickets to the Space Station on 10 May when the Soyuz examination board declared them qualified to fly.

The trip from Moscow to Baikonur is more than 2000 km, roughly five times the distance to their next home in space. Luca’s Soyuz will arrive at the orbital outpost in under seven hours – only two hours longer than today’s plane journey to the launch site.

The crew will stay at the traditional Cosmonaut Hotel for the last days before launch. Luca, Fyodor and Karen will be quarantined to make sure they do not take any unwanted bacteria or viruses to the Space Station. Family and support personnel such as flight surgeons will be the only people allowed to stay with them.

Cosmonauts Pavel Vinogradov, Alexander Misurkin and NASA astronaut Chris Cassidy are already on the Station and will welcome the new Expedition when the Soyuz docks on 29 May.

Luca’s Volare mission is provided through an agreement with Italy’s ASI space agency. His busy schedule of science and maintenance involves two spacewalks to install new equipment and retrieve experiments.

Watch the launch live on 28 May from 20:00 GMT (22:00 CEST) and follow the Volare blog for updates from the mission directors and Luca himself.

4 Notes

Spacewalk repairing ammonia leak

Astronauts Chris Cassidy and Tom Marshburn ventured into space on 11 May 2013 and replaced a pump unit on the outside of the International Space Station that was leaking ammonia

After more than five hours working outside, the astronauts reentered the Station. Liquid ammonia is used to keep the Space Station at the right temperature by being pumped through external radiators to lose excess heat.

Credits: NASA

1 Notes

Abell S1077

Galaxy cluster Abell S1077, as seen by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 and the Advanced Camera for Surveys.

The cluster acts as a magnifying glass, its gravity high enough to warp even the fabric of space-time. This effect distorts the path that light from distant galaxies takes when it travels through the cluster, as can be seen here in the bright arcs smeared around the centre of Abell S1077.

The phenomenon of gravitational lensing allows astronomers to see objects that are aligned behind the cluster and that would otherwise be undetectable from Earth.

This image is based in part on data spotted by Nick Rose in the Hubble’s Hidden Treasures image processing competition.

Credits: ESA/Hubble & NASA; Acknowledgement: N. Rose

3 Notes

Proba-V’s first image

First raw image from the Proba-V satellite, acquired over France’s west coast on 15 May 2013. The image was generated using the three VNIR bands, blue, red and near-infrared (NIR) superposed, the green being replaced by the NIR. It has not yet been radiometrically or geometrically corrected. Less than a cubic metre in volume, the miniaturised ESA satellite is tasked to map land cover and vegetation growth across the entire planet every two days.

Credits: ESA

1583 Notes

Reblogged:

4gifs

dlsrlz:

andthengreenmetblue:

one of my favourite posts on tumblr

Preach

(Source: ilovecharts)

118983 Notes

Reblogged:

sd60macintosh2748

StarStuff

About Me

Blogs I follow: