Category: Orion

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You may be familiar with Betelgeuse, as it is the upper-left star in the constellation Orion, forming what would be his shoulder. But this is an image of Betelgeuse that you wouldn’t see with your own eyes or even your own telescope. Images taken with the Akari infrared telescope show that as Betelgeuse travels through the interstellar medium, it creates what is called a “bow shock”.

Betelgeuse (pronounced “beetle-juice”, just like the 80’s film starring Michael Keaton) is a red supergiant 640 light-years from Earth, and is located in the winter constellation Orion. It travels through the interstellar medium at 30 km/sec (19 miles/sec). It’s not the star itself that creates the bow shock, but rather the interaction of the stellar wind emanating from Betelgeuse with the gas in the interstellar medium.

As Betelgeuse plows through the interstellar medium, the wind that it’s spewing out at 17 km/sec (11 miles/sec) warms up the surrounding gas – which originates from star-forming regions in Orion’s Belt – releasing light in the infrared. There is a rather strong current of interstellar gas in the area surrounding Betelegeuse, and just like the wave of water that is produced in front of a boat traveling over a lake, the dust and gas bunches up in front of Betelgeuse in the direction of travel.

The bow shock is approximately 3 light-years across, and the interaction it has with the stellar wind from Betelgeuse gives astronomers a better understanding of the density of the interstellar medium in the region, which in turn can help them get a better picture of the star forming regions in Orion’s Belt that are the source of the gas.

If you turned your telescope towards the Betelgeuse star, you sadly would not be able to see the bow shock. Akari created the image using a composite of images taken at 65 (blue), 90 (green) and 140 (red) micrometers, well below what the human eye can see.

Source: ESA, Bad Astronomy

For three weeks, 23 volunteers spent time helping NASA test a new life support system for the spacecraft that will replace the shuttle. Five volunteers at a time would squeeze into a special room the size of a walk-in closet for eight hours. Sweating and heavy breathing was encouraged, as scientists at Johnson Space Center wanted to measure the amount of moisture and carbon dioxide absorbed by a new system designed to control carbon dioxide and humidity inside a crew capsule in order to make air breathable and living space more comfortable. The tests took place from April 14 to May 1 of this year and are some of the first to use human subjects in support of NASA’s Orion crew capsule, Altair lunar lander and lunar rovers.

“We’re moving from paper studies to tests with hardware that will evolve and become part of the spacecraft that will fly back to the moon,” said test volunteer and NASA engineer Evan Thomas at Johnson.

Known as the Carbon-dioxide and Moisture Removal Amine Swing-bed, or CAMRAS, the new system will help sustain life on exploration vehicles and reduce the dependence on resupply from Earth.

“Our goal for CAMRAS is to develop a simple, regenerative, lightweight device that will work for both the Orion crew capsule and the Altair lunar lander,” said lead researcher Jeff Sweterlitsch.

The Exploration Life Support project also is developing technologies that will recover oxygen and water vapor, recycle spacecraft wastewater into drinking water and recover usable resources from wastes.

This series of tests put volunteers inside a test chamber scaled to be the size of the Orion crew capsule, about 570 cubic feet. The volunteers, who were selected and grouped to replicate a typical crew, were asked to sleep, eat and exercise during test sessions that lasted from a few hours to overnight.

“The air smelled a little artificial, like on a plane, and it was a little crowded,” said Aaron Hetherington, one of the volunteers and a director for the test. “But the air was fine; the temperature comfortable. My biggest observation is that it was unremarkable, which is good because that means the hardware was working.”

Two additional phases of testing on CAMRAS are planned.

Video of the tests are available on NASA TV

Original News Source: NASA Press Release

I know what you’re thinking, and no, that’s not a UFO in a secret government laboratory. It’s not a prop for an upcoming science fiction movie, and it’s not the world’s largest Frisbee. It’s a prototype heat shield, developed by Boeing for NASA’s Orion Crew Exploration Vehicle.

When Orion returns from space, it needs to decelerate from orbital velocity to be able to land safely. Just like the space shuttle, the capsule will point this heat ablating surface into the atmosphere, and let it get super hot. The heat shield can rise to extremely high temperatures, while the astronauts stay nice and safe.

The lunar protective system will need to be much more capable that the shuttle’s system, since capsules will be returning directly to the Earth after flying from the Moon. In some cases, Orion’s thermal protection will face 5 times as much heat as vehicles returning from the International Space Station. That’s hot.

It was the catastrophic failure of Columbia’s heat shield that doomed it when it was re-entering the Earth’s atmosphere. Needless to say, NASA wants to get this right.

The contract for the new Thermal Protection System was awarded to Boeing Advanced Systems about a year ago. Last month, a NASA Ames technical and quality inspection team completed an acceptance review of the shield.

The shield is made from Phenolic Impregnated Carbon Ablator (PICA). That’s a mouthful, but it uses a special trick to keep the capsule cool. As the heat shield heats up during reentry, the PICA material “ablates”. It chars, melts and then sublimates to create a cool boundary layer that protects the spacecraft.

Boeing will continue working on the heat shield, to meet Orion’s TPS preliminary design review in early 2008.

Original Source: Boeing News Release