Annular Solar Eclipse and other space and astronomy news

NTDTV on YouTube has this week's top story in Annular Solar Eclipse Seen from Australia's Outback.

Scientists and astronomers from around the world gathered at Tennant Creek In Australia's outback to view an annular Solar eclipse on Friday, beginning just before 7 a.m.
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The next total solar eclipse will be visible from Africa, Southern Europe and Eastern Americas in November 2013.

Follow over the jump for the rest of this past week's space and science news.

NASA Television on YouTube: Coolant Pump Replaced on ISS on This Week @NASA

Outside the International Space Station, Expedition 35 Flight Engineers Chris Cassidy and Tom Marshburn of NASA conducted a 5-hour, 30-minute spacewalk on the station's P6 truss to replace a suspect pump controller box which distributes coolant to the station's thermal control system. The quick-turnaround spacewalk was mounted just 48 hours after an ammonia coolant leak developed on P6. After installing the spare pump, power was turned on, and the system appeared to be working properly with no indications of ammonia leaking from the pump. Also, Humans 2 Mars, 40th Anniversary of Skylab, Marshburn "Testifies" From Space, Next ISS Crew Focused on Launch, Curiosity Rover Update, Landsat's Vegas Time-Lapse, Fruit Flies Improving Flight, Student Launch Projects and more!

DarkSyde at Daily Kos has more general space and science news in This week in science: Highs and lows.  Irene Klotz of Reuters writes more about the spacewalk in Spacewalking repairmen replace space station's leaky pump.

A pair of spacewalking astronauts wrapped up a hastily planned repair job on Saturday to replace a suspect coolant pump needed to keep the International Space Station at full power.

NASA astronauts Chris Cassidy and Tom Marshburn put on spacesuits and left the space station's airlock shortly before 9 a.m. EDT to attempt to stem an ammonia coolant leak that cropped up on Thursday.

Over the next four hours, they installed a spare pump, then positioned themselves to check for signs of escaping ammonia ice crystals when the system was turned back on.

"No flakes," Cassidy reported to flight controllers at the Johnson Space Center in Houston.

Now for the news from the perimeter of the Solar Systemm to the surface of the Earth itself, beginning with Getting to Know Your Solar System (32): Tethys
by Troubadour on Daily Kos.

Saturn's moon Tethys is a rough, pitted ice carcass of a world, and is in many ways emblematic of most of its fellow moons: Ancient, composed almost completely of water ice, geologically dead, and brutally scarred.  It typifies an entire class of satellite in the system, bearing so great a resemblance to its larger, more distant counterparts Dione and Rhea that it's often difficult to tell them apart at a glance.

Next, NASA Television on YouTube: ScienceCasts: Sunset Triangle

The three brightest planets in this month's night sky are lining up for a beautiful sunset conjunction at the end of May.

As the report moves inward, here are two news items about Earth's Moon and an item about the second human to step foot on it.

Nature (UK): Common source for Earth and Moon water
Chemical fingerprints of lunar rocks suggest both bodies already had their water at birth.
Ron Cowen
09 May 2013

Measurements of the chemical composition of Moon rocks suggest that Earth was born with its water already present, rather than having the precious liquid delivered several hundred million years later by comets or asteroids. And in finding a common origin for the water on Earth and the Moon, the results highlight a puzzle over the leading theory for the formation of Earth's satellite.

Geochemist Alberto Saal of Brown University in Providence, Rhode Island, and his colleagues built on recent studies, including their own, that have revealed a substantial amount of water in the Moon’s interior. To find the source of the water, the team relied on a chemical fingerprint — the relative amounts of hydrogen and deuterium, a hydrogen isotope that has one extra neutron in its atomic nucleus.

In investigating primitive lunar samples carried to Earth by the Apollo 15 and 17 missions, the team found a deuterium-to-hydrogen ratio that matched the isotopic ratio in carbonaceous chondrites, which include some of the most primitive meteorites known. The ratio is also similar to that found in water on Earth. The findings “suggest a common source of water for both objects” and provide “a very important new constraint for models of Earth and Moon origin”, says planetary scientist Robin Canup of the Southwest Research Institute in Boulder, Colorado, who was not part of the study.

Nature (UK): Moon rocks offer new view of lunar dynamo
Process that generated magnetism lasted 160 million years longer than previously thought.
Alexandra Witze
06 May 2013

The Moon clung to its magnetic field until at least 3.56 billion years ago, a study suggests — about 160 million years longer than scientists had thought.

That small change may be enough to rule out some ideas about how the Moon generated and held onto its ancient magnetism, through a process known as a dynamo.

“It seems like the lunar dynamo lasted very late in the Moon’s history,” says Benjamin Weiss, a palaeomagnetics expert at the Massachusetts Institute of Technology (MIT) in Cambridge. “That’s a very surprising result.”

Space.com on YouTube: Buzz Aldrin's Visions For Missions: Mars and More | Video - Part 1

The Apollo 11 Moonwalker stopped by the SPACE.com newsroom to talk about his new book 'Mission To Mars'.

Speaking of ideas for the future...

Nature (UK): NASA astrophysicists seek ideas for the next 30 years
Posted by Alexandra Witze
06 May 2013

Why plan for 10 years out when you can plan for 30? One NASA advisory group is going for the long haul: between now and December it intends to draw up “a compelling, 30-year vision” for NASA’s astrophysics division.

This might seem like overkill, given that astronomers already perform “decadal surveys” every 10 years to prioritize future missions. In fact, the latest decadal survey came out just three years ago, with a midterm review due to start two years from now. The new  ‘roadmap’ isn’t meant to replace the decadal survey process, says NASA’s Paul Hertz, head of the astrophysics division. “What the roadmap does is it looks out 30 years and provides a vision of what astrophysics might do,” he told a virtual town-hall meeting on 6 May.

In other words, more of a wish list than a prioritizing document.

And that's it for this past week's news.