Archive for April, 2010

UGPSJ0722-05

Tuesday, April 13th, 2010

Philip Lucas at the University of Hertfordshire, UK, and his international team are part of the UKIDSS Galactic Plane Survey, a program that uses the UK Infrared Telescope (UKIRT) in Hawaii to hunt for objects that glow in infrared, have spotted a brown dwarf 10 light-years from Earth. This makes it the nearest brown dwarf and one of ten nearest stellar objects to our solar system. It’s chemical composition of its atmosphere is a bit of a conundrum. UGPSJ0722-05 is  floating through interstellar space all by itself.

Brown dwarfs are sub-stellar objects which are too low in mass to sustain stable hydrogen fusion. Their mass is below that necessary to maintain hydrogen-burning nuclear fusion reactions in their cores, as do stars on the main sequence, but which have fully convective surfaces and interiors, with no chemical differentiation by depth. Brown dwarfs occupy the mass range between that of large gas giant planets and the lowest mass star. They emit in infrared, radiation the UKIDSS survey is sensitive to.

The UKIRT has already detected many cool brown dwarfs, but UGPSJ0722-05 appears to be the coolest ever discovered. It could have a surface temperature as low as 400 Kelvin, even cooler than the team’s previous record of slightly below 500 K.

Using the Gemini Observatory, follow-up spectroscopic analysis has detected methane and water vapor in its atmosphere. The presence of organic compounds is an extremely hot topic.

Interestingly, when looking at the spectrum from UGPSJ0722-05, there is an anomalous absorption line that cannot be explained by our current knowledge of brown dwarfs. This could be a new breed of brown dwarf or very cool object with some chemical in its atmosphere that absorbs infrared radiation at a wavelength of 1.25 micrometers.

NASA’s Unmanned Global Hawk Aircraft Makes First Science Flight

Monday, April 12th, 2010

WASHINGTON — NASA has successfully completed the first science flight of the Global Hawk unpiloted aircraft system over the Pacific Ocean. The flight was the first of five scheduled for this month’s Global Hawk Pacific, or GloPac, mission to study atmospheric science over the Pacific and Arctic oceans.

The Global Hawk is a robotic plane that can fly autonomously to altitudes above 60,000 feet — roughly twice as high as a commercial airliner — and as far as 11,000 nautical miles, which is half the circumference of Earth. Operators pre-program a flight path, then the plane flies itself for as long as 30 hours, staying in contact through satellite and line-of-site communications links to a ground control station at NASA’s Dryden Flight Research Center in California’s Mojave Desert.

“The Global Hawk is a revolutionary aircraft for science because of its enormous range and endurance,” said Paul Newman, co-mission scientist for GloPac and an atmospheric scientist from NASA’s Goddard Space Flight Center in Greenbelt, Md. “No other science platform provides the range and time to sample rapidly evolving atmospheric phenomena. This mission is our first opportunity to demonstrate the unique capabilities of this plane, while gathering atmospheric data in a region that is poorly sampled.”

GloPac researchers plan to directly measure and sample greenhouse gases, ozone-depleting substances, aerosols, and constituents of air quality in the upper troposphere and lower stratosphere. GloPac’s measurements will cover longer time periods and greater geographic distances than any other science aircraft.

During Wednesday’s flight, the plane flew approximately 4,500 nautical miles along a flight path that took it to 150.3 degrees West longitude, and 54.6 degrees North latitude, just south of Alaska’s Kodiak Island. The flight lasted just over 14 hours and flew up to 60,900 feet. The mission is a joint project with the National Oceanic and Atmospheric Administration, or NOAA.

The plane carries 11 instruments to sample the chemical composition of the troposphere and stratosphere. The instruments profile the dynamics and meteorology of both layers and observe the distribution of clouds and aerosol particles. Project scientists expect to take observations from the equator north to the Arctic Circle and west of Hawaii.

Although the plane is designed to fly on its own, pilots can change its course or altitude based on interesting atmospheric phenomena ahead. Researchers have the ability via communications links to control their instruments from the ground.

“The Global Hawk is a fantastic platform because it gives us expanded access to the atmosphere beyond what we have with piloted aircraft,” said David Fahey, co-mission scientist and a research physicist at NOAA’s Earth System Research Laboratory in Boulder, Colo. “We can go to regions we couldn’t reach or go to previously explored regions and study them for extended periods that are impossible with conventional planes.”

The timing of GloPac flights should allow scientists to observe the breakup of the polar vortex. The vortex is a large-scale cyclone in the upper troposphere and lower stratosphere that dominates winter weather patterns around the Arctic and is particularly important for understanding ozone depletion in the Northern Hemisphere.

Scientists also expect to gather high-altitude data between 45,000 and 65,000 feet, where many greenhouse gases and ozone-depleting substances are destroyed. They will measure dust, smoke and pollution that cross the Pacific from Asia and Siberia and affect U.S. air quality.

The Global Hawk will make several flights directly under the path of NASA’s Aura satellite and other “A-train” Earth-observing satellites, “allowing us to calibrate and confirm what we see from space,” Newman added. GloPac is specifically being conducted in conjunction with NASA’s Aura Validation Experiment.

The GloPac mission includes more than 130 researchers and technicians from NASA’s Goddard Space Flight Center, Dryden Flight Research Center, Jet Propulsion Laboratory in Pasadena, Calif., and Ames Research Center in Moffett Field, Calif. Also involved are NOAA’s Earth System Research Laboratory; the University of California, Santa Cruz; Droplet Measurement Technologies of Boulder, Colo.; and the University of Denver.

NASA Dryden and the Northrop Grumman Corp. of Rancho Bernardo, Calif., signed a Space Act Agreement to re-fit and maintain three Global Hawks transferred from the U.S. Air Force for use in high-altitude, long-duration Earth science missions.

For GloPac imagery and other information on the mission, visit:
http://www.nasa.gov/topics/earth/features/global-hawk.html

This news story is directly from NASA.gov

Anniversary of Gagarin, Shuttle, Apollo 13

Monday, April 12th, 2010

Today, April 11th, Soviet cosmonaut Yuri Gagarin who made the historic first manned space flight. It is the this is the 49th anniversary. Today is also the 29th anniversary of the first space shuttle flight. That’s not enough! “Houston, We’ve had a problem.”  It’s also the anniversary of the safe return of the Apollo 13 mission.

Epsilon Aurigae Eclipse Mystery Solved

Monday, April 12th, 2010

Epsilon Aurigae is located 2,000 light years from Earth in the northern constellation Auriga. It is one of the brightest stars but since the 1820s its light is halved in intensity for 18 months. It occurs once every 27.1 years.

Recently, the mystery surrounding the ‘eclipse’ has been solved, according to high-resolution images published in the journal Nature, points to a thin, dark and dense disk of dust that passes edge-on in front of the star, filtering out some of the light that reaches us. The dense disk of dust is thought to be a rare phase of stellar life, the building blocks of planets, and there is no other star system like this known.

The 26th National Space Symposium

Monday, April 12th, 2010

This event takes place in Colorado Springs, Colorado. It is a week long summit for the aerospace industry. A hot topic is the budget by President Barack Obama, which increases the role of commercial space exploration.  NASA Administrator Charles Bolden will even discuss the government’s vision for the private industry on Tuesday.  Space tourism, which companies have recently explored is a huge hot topic at the event.

More information can be found here: http://www.nationalspacesymposium.org/