NASA Archives

July 19, 2007December 26, 2015 by Fraser Cain

Saturn’s 60th Moon Discovered

Saturn’s little system hit a big milestone this week with the announcement of its 60th moon. This new moon joins the crop of new satellites turned up by researchers poring through data sent back by NASA’s Cassini spacecraft.

The newly discovered moon first appeared as a faint dot in a series of images captured by Cassini on May 30. The discoverers, from Queen Mary, University of London, then went back through the vast library of Cassini images, verifying that they had found a new object.

Codenamed “Frank” for now, the new moon is only about 2 km (1.2 miles) across, and it’s mostly made of ice and rock. It’s located in between the orbits of Methone and Pallene.

This is the fifth new moon discovered by the Cassini imaging team.

Original Source: Cassini-Huygens News Release

July 16, 2007December 26, 2015 by Fraser Cain

Building an Engine that Can Throttle Down

Here on Earth, we’ve gotten used to the concept of a car’s accelerator pedal. Put it down a little, and the car accelerates slowly. Put the “pedal to the metal” and you’ll go faster. Imagine trying to park your car when you only have two choices: off and full speed. Developing a similar concept for a rocket is very difficult. Most rockets are designed to go at full blast, or nothing at all.

A variable acceleration rocket would tremendously useful for landing on the Moon. Instead of firing the landing rockets in short bursts, astronauts could throttle down for a nice smooth landing. But building an engine like this is harder than it sounds.

NASA researchers think they’ve got a prototype engine that should give the variable rate of acceleration astronauts are looking for. The newly developed Common Extensible Cryogenic Engine (CECE) is a variant on the RL10 engine that boosted the Surveyor robot landers to the Moon back in 1966-68. The RL10 is designed to only go full throttle, so adding the variable thrust was difficult.

The main problem is that changing the throttle affects how the whole engine functions. At low power, liquid hydrogen can slow and vapourize in the coolant lines. This might cause the engine to stall. During one test, the experimenters discovered that the engine “chugged”, vibrating 100 times a second. It turned out oxygen vapours were forming on the injector plate, inhibiting normal flow, causing the vibrations.

It’s not ready for space yet, but CECE might eventually become part of the design of a future lunar lander. The astronauts returning to the Moon will be very appreciative.

Original Source:Science@NASA

July 12, 2007December 26, 2015 by Fraser Cain

Station’s New Oxygen Generation System Activated

Apparently astronauts want to breathe. In their mad quest for air, the astronauts on board the International Space Station activated the new US-built oxygen generation system, designed to assist the intermittent Russian Elektron system.

The new oxygen generation system (or OGS) was turned on for the first time on Wednesday. Although there were a few glitches in the beginning, it’s been running fine today, and should start producing oxygen later today.

The OGS is capable of producing between 5 and 9 kgs(12 and 20 pounds) of oxygen a day. That much won’t be needed today, with only three crew members on board the station, but it’ll be critical when it has the full complement of six astronauts on board.

One of the OGS’ advantages is that it uses a solid polymer to assist the electrolysis of water into hydrogen and oxygen. The Russian system uses a liquid called potassium hydroxide. It turns out that this liquid had flowed around inside the Elektron, and clogged up one of the hydrogen valves, disabling it.

Original Source: NASA News Release

July 3, 2007December 26, 2015 by Fraser Cain

NASA’s New Einstein Probes Office

Albert Einstein made enough predictions about the nature of gravity and relativity that NASA has dedicated a whole office and fleet of spacecraft to him. This week the space agency announced their new Einstein Probes Office, where they’ll be compiling evidence for the strangest stuff in the Universe: dark energy, black holes, and the cosmic microwave background radiation.

The Beyond Einstein program consists of 5 proposed spacecraft; two major spacecraft, and 3 smaller probes. The two major missions are already in the works, and include the Laser Interferometer Space Antenna (LISA), which will orbit the Sun and measure gravitational waves. Constellation-X will watch matter falling into supermassive black holes.

The smaller probes include missions to investigate the nature of dark energy, the physics of the Big Bang, and the distribution and types of black holes in the universe. NASA has already approved preliminary studies into some of these missions.

NASA and the U.S. Department of Energy have put together a committee to figure out which missions should be launched first, and will release their findings in September, 2007.

Original Source:NASA Goddard

June 26, 2007December 26, 2015 by Fraser Cain

Double Supernovae Discovered

Supernovae are rare events, only occurring once every 25-100 years in galaxy. So it came as a complete surprise when NASA’s Swift satellite turned up two supernovae going off at the same time in a galaxy – separated by only 16 days.

Until now, astronomers have never seen a supernova going off in the galaxy MCG +05-43-16, and then suddenly: kaboom kaboom. The twin supernovae have been categorized SN 2007ck and SN 2007co.

And they’re completely different events. The first, SN 2007ck, is a Type II supernova, where a star with many times the mass of our own Sun runs out of fuel and collapses catastrophically. This creates a black hole or neutron star, and blows the outer layers of the star into space.

The second, SN 2007co is a Type Ia event. This is where a white dwarf star steals material from a binary partner until it can’t hold any more material, and detonates in a massive blast.

This is a complete coincidence. The two events are separated by tens of thousands of light years of space. In fact, an astronomer in the galaxy might see the two events separated by thousands of years.

Original Source: NASA

June 22, 2007December 26, 2015 by Fraser Cain

Atlantis Home from STS-117

The space shuttle Atlantis touched down Friday afternoon after a successful mission servicing the International Space Station. Because of bad weather in Florida, the shuttle was delayed a day, and finally re-routed to Edwards Air Force Base in California. It touched down at 3:49 pm EDT.

Over the course of their 14-day mission in space, the astronaut crew installed the new S3/S4 truss to the station, and deployed the new solar wings. They also retracted an older solar array, and performed some other minor fixes.

One of the big concerns was a thermal blanket that dislodged during Atlantis‘ launch. The astronauts tucked the blanket back in during one the mission’s 4 spacewalks. Whether or not the repair was necessary, Atlantis returned through the Earth’s atmosphere without a problem.

The next mission, STS-118, is scheduled for August and will deliver the S5 truss segment to the station.

Original Source : NASA

June 19, 2007December 26, 2015 by Fraser Cain

Tiny Mimas Beneath the Rings

Here’s a cool picture taken by Cassini of Saturn and one of its moons, Mimas – 397 kilometers (247 miles) across. If you look really closely, Mimas is that grey dot down near the bottom right-hand corner of the picture. Cassini took this photo on May 11, 2007 when it was approximately 720,000 kilometers (448,000 miles) from Saturn.

Original Source: NASA/JPL/SSI News Release

June 12, 2007December 26, 2015 by Fraser Cain

Journey to the Centre of the Earth’s Position in Space

NASA researchers have developed a new technique that gives them a precise measurement for the position of the centre of the Earth, to the closest millimetre. This is harder than it sounds, since the centre doesn’t stay in one position.

As the Earth rotates in space, its centre of mass ranges over a distance of 2 to 5 millimetres (.08 to .20 inches) a year. Until now, the best calculations differed by 1.8 millimetres a year. That doesn’t sound like much, but its actually important for very precise measurements. For example, the rise in global sea level due to increasing temperatures is measured in a handful millimetres. In other places, the Earth is rebounding after the weight of glaciers during the last ice age, 20,000 years ago.

The researchers combined 4 different space-based techniques to get this accurate measurement: the global positioning system, laser stations that track orbiting satellites, radio telescopes that measure the position of the Earth against quasars, and a French network of tracking satellites called DORIS.

Original Source: NASA/JPL News Release

May 31, 2007December 26, 2015 by Fraser Cain

NASA Administrator Isn’t Sure Global Warming is a Problem

I’ve got to say, I nearly fell out of my chair when I read this today. NASA Administrator Mike Griffin was interviewed on NPR about the threat of global warming. Apparently, he’s not convinced it’s a problem.

When it comes to the science on global warming, NASA is one of the good guys. They’ve got a fleet of spacecraft and aircraft analyzing every aspect of the planet. They measure ice levels, global temperatures, cloud cover, ocean levels, snow melt, rainfall patterns, dust storms, desertification and more. It’s amazing how many scientific instruments they have working on this project. They have luminaries from the scientific community working for them, like Dr. James Hansen.

And they release a hail of press releases. Just from the last week, we’ve got a story about how they detected increased snow melt in Antarctica, measuring Greenland’s glaciers, and a new release about how the Earth’s climate is approaching the point of no return.

Here’s what Griffin said on NPR:

I have no doubt that … a trend of global warming exists. I am not sure that it is fair to say that it is a problem we must wrestle with.

So he’s convinced that global warming is happening and it’s man made. But he thinks it’s arrogant for humans to decide what the perfect climate is.

… I would ask which human beings – where and when – are to be accorded the privilege of deciding that this particular climate that we have right here today, right now is the best climate for all other human beings. I think that’s a rather arrogant position for people to take.

Wow.

Sure, there’s a possibility that dramatic climate change could end up being better overall for the majority of humans on Earth, on average.

But there’s also a possibility that it’s not the case. That severe climate disruption will be terrible for a huge percentage of the population of the Earth. That the wrenching effects of change will hit the people least able to defend against it, and will suffer the most: the poor in undeveloped countries. Griffin thinks it’s okay to roll the dice. That’s it’s arrogant to not roll the dice.

If it’s okay to take that chance; if it’s arrogant to err on the side of caution, why bother investing in climate science at all? Just cut the funding, and take your chances.

NASA went into damage control mode today after Griffin’s statement, and posted a statement on its website.

“NASA is the world’s preeminent organization in the study of Earth and the conditions that contribute to climate change and global warming. The agency is responsible for collecting data that is used by the science community and policy makers as part of an ongoing discussion regarding our planet’s evolving systems. It is NASA’s responsibility to collect, analyze and release information. It is not NASA’s mission to make policy regarding possible climate change mitigation strategies. As I stated in the NPR interview, we are proud of our role and I believe we do it well.”

But this statement doesn’t really take back what Griffin said. I suspect he’s going to have an uncomfortable few weeks.

May 3, 2007March 3, 2023 by Fraser Cain

Train Carrying Shuttle Parts Derails

A Union Pacific train carrying space shuttle parts derailed on Wednesday, injuring six people. The train derailed when the wooden trestle it was traveling across collapsed, near the Tombigbee River in western Alabama.

The train was carrying 8 solid rocket booster motors and two end cones for future shuttle missions. These are interchangeable parts, and would be used for upcoming shuttle missions in October and December. It’s not known if the derailment will cause a delay for any upcoming mission. The next launch of the space shuttle Atlantis, scheduled for June, won’t be delayed, because the spacecraft already has its boosters.

Original Source: Reuters Article