Wednesday, February 29, 2012
Vowing to continue Mars exploration at a more measured, affordable pace after pulling out of a joint sample return program with Europe, the head of NASA’s science directorate said Monday the space agency is launching a feverish study to lay the groundwork for a robotic mission to the red planet in 2018.
It was welcome news at a meeting of Mars scientists outside Washington this week, but researchers may have trouble crafting a Mars mission to their liking at a cost cap of about $700 million, the figure floated by NASA science chief John Grunsfeld.
The planetary science decadal survey, a report prepared by an independent panel of researchers, recommended last year NASA should pursue a mission to select, gather and store rock samples on the surface of Mars in the coming decade, but only if it fit within the space agency’s budget.
With NASA’s budget outlook yielding little money for such an ambitious Mars mission, scientists went back to the drawing board.
The budget blueprint proposed by President Barack Obama on Feb. 13 would slash NASA’s Mars budget from $587 million in fiscal year 2012, to about $361 million next year, then dropping to less than $189 million by fiscal 2015.
NASA named Orlando Figueroa, a veteran Mars program manager, to head a planning board to create a new framework for the space agency’s Mars strategy. An interim report is due March 15, and the committee will complete its work this summer.
Engineers in Utah started crafting another five-segment solid rocket motor this week for a ground-shaking test firing to qualify the 22-million horsepower booster for flight on NASA’s Space Launch System in 2017.
The qualification campaign, led by rocket-builder ATK, will prove the solid-fueled motor is ready to help propel the Space Launch System from Earth on two test flights in 2017 and 2021. The 320-foot-tall rocket will launch unmanned first, and NASA says the second mission will carry astronauts on a trip around the moon inside an Orion capsule.
Each launch will be powered by two five-segment solid rocket boosters and hydrogen-fueled first stage engines left over from the space shuttle program.
Satisfied with the motor’s design after three development motor firings in the Utah desert, ATK and NASA will ignite another rocket in a test stand in the spring of 2013.
“We’re in the process of having QRRs, which are the readiness reviews for the first qualification motor firing,” said Todd May, NASA’s SLS project manager at the Marshall Space Flight Center in Huntsville, Ala. “That motor is scheduled to be tested in the spring of 2013. That test will baseline the performance and qualify the motor for flight.”
The qualification readiness reviews are due to be finished in April, then technicians in June will begin casting each of the motor’s segments with a recipe of solid propellant.
Tuesday, February 28, 2012
To see if life does lurk beneath the frigid crust of one of Saturn’s moons, scientists are developing a powerful drill that can melt and bore its way down to the moon’s icy depths.
Giant jets of water ice have been seen spewing into space from cryovolcanoes on Enceladus, Saturn’s sixth largest moon. When NASA’s Cassini spacecraft flew through these icy fountains, the probe detected organic compounds that hinted at the possibility of life.
But the problem with investigating cryovolcanoes for alien life is that landing directly on them is too risky. Furthermore, any potential traces of life could be destroyed during their launch from the fissures and subsequent exposure to the hostile conditions of space.
Instead, researchers are envisioning ways to dig into the icy crust of Enceladus to look for signs of life in the water that is thought to lurk beneath the moon’s surface, before the icy fountains burst upward.
The concept is to establish a base station that is a safe distance from a cryovolcano on the surface of Enceladus. This base station would power a probe dubbed IceMole, which is designed to melt and drill its way down to a depth of 330 to 660 feet (100 to 200 meters) at speeds of about 3 feet (1 meter) per hour.
Friday, February 24, 2012
Our Milky Way galaxy may be teeming with rogue planets that ramble through space instead of being locked in orbit around a star, a new study suggests.
These “nomad planets” could be surprisingly common in our bustling galaxy, according to researchers at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), a joint institute of Stanford University and the SLAC National Accelerator Laboratory. The study predicts that there may be 100,000 times more of these wandering, homeless planets than stars in the Milky Way.
If this is the case, these intriguing cosmic bodies would belong to a whole new class of alien worlds, shaking up existing theories of planet formation. These free-flying planets may also raise new and tantalizing questions in the search for life beyond Earth.
“If any of these nomad planets are big enough to have a thick atmosphere, they could have trapped enough heat for bacterial life to exist,” study leader Louis Strigari said in a statement.
And while nomad planets cannot benefit from the heat given off from their parent stars, these worlds could generate heat from tectonic activity or internal radioactive decay, the researchers said.
Wednesday, February 22, 2012
Observations by the NASA/ESA Hubble Space Telescope have come up with a new class of planet, a waterworld enshrouded by a thick, steamy atmosphere. It’s smaller than Uranus but larger than Earth.
An international team of astronomers led by Zachory Berta of the Harvard-Smithsonian Center for Astrophysics (CfA) made the observations of the planet GJ 1214b.
“GJ 1214b is like no planet we know of,” Berta said. “A huge fraction of its mass is made up of water.”
The ground-based MEarth Project, led by CfA’s David Charbonneau, discovered GJ 1214b in 2009. This super-Earth is about 2.7 times Earth’s diameter and weighs almost seven times as much. It orbits a red-dwarf star every 38 hours at a distance of 2 million kilometres, giving it an estimated temperature of 230 degrees Celsius.
In 2010, CfA scientist Jacob Bean and colleagues reported that they had measured the atmosphere of GJ 1214b, finding it likely that it was composed mainly of water. However, their observations could also be explained by the presence of a planet-enshrouding haze in GJ 1214b’s atmosphere.
Berta and his co-authors, who include Derek Homeier of ENS Lyon, France, used Hubble’s Wide Field Camera 3 (WFC3) to study GJ 1214b when it crossed in front of its host star. During such a transit, the star’s light is filtered through the planet’s atmosphere, giving clues to the mix of gases.