Showing posts with label Nasa. Show all posts
Showing posts with label Nasa. Show all posts

NASA Picks Seven Commercial Spaceships for the Next Generation of Suborbital Science Missions




Virgin SpaceShip

The new post-shuttle NASA has said it aims to work more cooperatively with private space industry and outside sources of innovation in writing the next chapter in space exploration and science, and the agency is putting its money where its mouth is. After selecting 30 future technology proposals for funding earlier this week, NASA has now inked a number of much larger contracts with seven private space companies--including Virgin Galactic--to integrate and fly various technology payloads aboard their suborbital spacecraft.
We single out Virgin because its SpaceShipTwo is the furthest spacecraft along, development-wise, which means it could soon be ferrying scientific payloads into suborbital space, making it the first commercial company to take that role over from NASA in the post-shuttle era. SpaceShipTwo is already undergoing flight tests and could begin commercial operation as soon as next year.
That’s a big deal, because it’s a stepping stone toward fulfilling NASA’s vision of opening up space to more scientists and technology developers, and doing it on someone else’s less-expensive spacecraft. And Virgin isn’t the only company with a dog in this hunt: the other companies splitting the $10 million in contracts are Armadillo Aerospace, Near Space Corp., Masten Space Systems, Up Aerospace Inc., Whittinghill Aerospace LLC, and XCOR.
Many of these companies are looking to carry tourists into space, but the overarching idea of the Flight Opportunities Program (that’s the NASA funding initiative) is to cultivate a variety of ways for researchers to get their experiments--manned or unmanned--into space as well. There’s a lot of benefit to be spread around in doing so.
For one, it opens up suborbital space to groups that couldn’t afford it or simply couldn’t make the manifest on prior NASA missions (which were quite selective and pricey per pound of cargo). It also supports the private space industry by opening up another revenue stream for the Virgins and XCORs and Mastens of the world. But perhaps most importantly for NASA it means a proliferation in space science and technology development, and technologies that fall out of this program just might become part of NASA’s next-gen space transportation model.
Source: SPACE

Russia launches 'largest telescope ever made'

To look at the Russian RadioAstron spacecraft, which launched from Kazakhstan this Monday, it doesn't seem particularly record-breaking. Its 10-meter (33-foot) antenna is certainly no match for those on earthbound radio telescopes, which can be up to 300 meters (984 feet) across. Once in orbit, however, its signal will join forces with those from ground-based telescopes to form one giant virtual telescope. Using a process known as interferometry, they will form the equivalent of a single radio telescope dish that at over 350,000 kilometers (217,480 miles) across is almost 30 times wider than the Earth. Although it's not actually one physical object, it is nonetheless being heralded as the largest telescope ever created.



Interferometry itself is nothing new, having been around since the 1960s. Very basically speaking, it involves combining the output of two or more geographically-separated telescopes to obtain one image with a resolution higher than either telescope could achieve on its own.
While radio telescopes have been sent into space for this purpose before, the plan is for RadioAstron's oval-shaped orbit to take it up to ten times farther than any of those other spacecraft have traveled, at 10,000 to 390,000 kilometers (6,214 to 242,335 miles) from Earth. Working with telescopes in locations such as West Virginia, Germany and Puerto Rico, it should be able to capture details at 10,000 times the resolution of the Hubble Space Telescope.
Plans for its use include the observation of a huge black hole at the center of a nearby galaxy, M87.
Although already launched, it will still be a few months before the spacecraft reaches the starting point of its orbit, and then goes through a check-out period with its ground control team at Russia's Lebedev Physical Institute Astro Space Center. Once it starts receiving and transmitting data ... well, there will be a lot of it. It's estimated that RadioAstron will be taking in up to 144 megabits per second, which will be continuously relayed to the ground.
So far, however, there is only one 22-meter (72-foot) dish set up to receive that data, near Moscow. This means that much of the data will simply be lost. It is hoped that throughout RadioAstron's five-year mission, more receiving stations can be set up.
Source: Gizmag via New Scientist

How does fire behave in zero gravity?

We all know about how fire behaves in outer space: It doesn't. All those action movies were wrong. Fire needs oxygen and oxygen isn't abundant outside of Earth's atmosphere. Fires can happen inside a contained, oxygenated environment in space, but they don't behave the way they do on Earth. The Earth's gravity imposes a lot of conditions on fire that wouldn't happen in microgravity or zero g. Here's why astronauts can't burn a candle at both ends.



Image: NASA - LRC
Gravity it is a mixed bag. Sure, it helps maintain muscle tone, and bone density, and allows us to eat soup in a bowl without any mess. Unfortunately, it also tries to kill us by tripping us up and pulling heavy objects down onto us. It turns out that, not content with blunt force trauma, gravity is also trying to kill us with fire. When a fire starts, it heats up the air around it. This causes that particular section of air to become less dense. That low-density section of air heads upwards because gravity is pulling down on everything and colder, denser sections of air muscle it out of the way to get closest to the earth. This is lucky for the fire, because the only reason the air got hot was because the fire was consuming the oxygen. When the low-density air got pushed up and out of the way by the oxygen-rich air, the fire got a new delivery of fresh oxygen to burn.



Not so in zero gravity. The air that's is heated by the fire does expand, but with no gravity pulling denser air down into its space, it just . . . stays there. Meanwhile the fire continues consuming oxygen and putting out carbon dioxide until it smothers itself. Space travel is so complicated, with so many problems having such drastic consequences, fire is one of the few ways that astronauts really catch a break. Unless there is some kind of air circulation system blowing over the fire, giving it fresh oxygen, a fire in a space craft would put itself out. Which is not to say that fire isn't discouraged. Here an astronaut in the International Space Station nervously chuckles that he can't give a demonstration of how a lit match will put itself out up there. There are rules about that kind of thing.
Some fires, for example candle flames, also change color in space. Part of a burning candle is very endothermic - heat consuming. When a candle wick burns, it is being taken apart molecule by molecule. This separation takes up heat. However, when the molecules, in this case long strings of carbon, get pushed upwards, they're burned like charcoal and glow bright yellow. In zero gravity, the carbon strings don't get burned, and the flame is blue, cooler, and much much dimmer. As awesome as it might seem, fire in zero gravity is a very low-drama affair.
Source: io9 Via Nasa, Scientific American, Newton AAS, and About.com.