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required three functioning wheels to maintain the precision pointing necessary to detect the signal of small Earth-sized exoplanets

With the failure of a second reaction wheel, the spacecraft can no longer precisely point at the mission's original field of view. The culprit is none other than our own sun

pushes the spacecraft around

the pressure exerted when the photons of sunlight strike the spacecraft

Without a third wheel to help counteract the solar pressure, the spacecraft's ultra-precise pointing capability cannot be controlled in all directions.

Kepler mission and Ball Aerospace engineers have developed an innovative way of recovering pointing stability by maneuvering the spacecraft so that the solar pressure is evenly distributed across the surfaces of the spacecraft

To achieve this level of stability, the orientation of the spacecraft must be nearly parallel to its orbital path around the sun

This technique of using the sun as the 'third wheel' to control pointing is currently being tested on the spacecraft and early results are already coming i

During a pointing performance test in late October, a full frame image of the space telescope's full field of view was captured showing part of the constellation Sagittarius

Photons of light from a distant star field were collected over a 30-minute period and produced an image quality within five percent of the primary mission image quality

Additional testing is underway to demonstrate the ability to maintain this level of pointing control for days and weeks.

The K2 mission concept has been presented to NASA Headquarters

A decision to proceed to the 2014 Senior Review – a biannual assessment of operating missions – and propose for budget to fly K2 is expected by the end of 2013

For four years, the space telescope simultaneously and continuously monitored the brightness of more than 150,000 stars, recording a measurement every 30 minutes.

ProVision, made by defense contractor L-3 Communications, a passenger enters a chamber that looks like a round phone booth and is scanned with millimeter waves, a form of low-energy radio waves, which have not been shown to strip electrons from atoms or cause cancer.

Some scientists argue the danger is exaggerated. They claim low levels stimulate the repair mechanism in cells, meaning that a little radiation might actually be good for the body.

But in the authoritative report on low doses of ionizing radiation, published in 2006, the National Academy of Sciences reviewed the research and concluded that the preponderance of research supported the linear link. It found “no compelling evidence” that there is any level of radiation at which the risk of cancer is zero.

Rebecca Smith-Bindman, a radiologist at the University of California, San Francisco, estimated that the backscatters would lead to only six cancers over the course of a lifetime among the approximately 100 million people who fly every year. David Brenner, director of Columbia University’s Center for Radiological Research, reached a higher number — potentially 100 additional cancers every year.

But in 1982, the FDA merged the radiological health bureau into its medical-device unit. “I was concerned that if they were to combine the two centers into one, it would probably mean the ending of the radiation program because the demands for medical-device regulation were becoming increasingly great,” said Villforth, who was put in charge of the new Center for Devices and Radiological Health. “As I sort of guessed, the radiation program took a big hit.”

As a result, there is an FDA safety regulation for X-rays scanning baggage — but none for X-rays scanning people at airports.

The U.S. Customs Service deployed backscatter machines for several years but in limited fashion and with strict supervision. Travelers suspected of carrying contraband had to sign a consent form, and Customs policy prohibited the scanning of pregnant women.

In July, a federal appeals court ruled that the agency failed to follow rule-making procedures and solicit public comment before installing body scanners at airports across the country

Federal Aviation Administration’s medical institute has advised pregnant pilots and flight attendants that the machine, coupled with their time in the air, could put them over their occupational limit for radiation exposure

It was made up of 15 people, including six representatives of manufacturers of X-ray body scanners and five from U.S. Customs and the California prison system. There were few government regulators and no independent scientists.

The FDA delegated the task of establishing the voluntary standards to the American National Standards Institute.

“Establishing a mandatory standard takes an enormous amount of resources and could take a decade to publish,” said Dan Kassiday, a longtime radiation safety engineer at the FDA.

and before 9/11, many states also had the authority to randomly inspect machines in airports. But that ended when the TSA took over security checkpoints from the airlines.

Last year, in reaction to public anger from members of Congress, passengers and advocates, the TSA contracted with the Army Public Health Command to do independent radiation surveys. But email messages obtained in a lawsuit brought by the Electronic Privacy Information Center, a civil liberties group, raise questions about the independence of the Army surveys.

One email sent by TSA health and safety director Jill Segraves shows that local TSA officials were given advance notice and allowed to “pick and choose” which systems the Army could check.

The TSA considered the scanners again after two Chechen women blew up Russian airliners in

Facing a continued outcry over privacy, the TSA instead moved forward with a machine known as a “puffer” because it released several bursts of air on the passengers’ clothes and analyzed the dislodged particles for explosives. But after discovering the machines were ineffective in the field and difficult to maintain, the TSA canceled the program in 2006.

Around that time, Rapiscan began to beef up its lobbying on Capitol Hill. It opened a Washington, D.C., office and, according to required disclosures, more than tripled its lobbying expenditures in two years, from less than $130,000 in 2006 to nearly $420,000 in 2008. It hired former legislative aides to Rep. David Price, D-N.C., then chairman of the homeland security appropriations subcommittee, and to Sen. Trent Lott, R-Miss.

In addition, it opened a new North Carolina plant in Price’s district and expanded its operations in Ocean Springs, Miss., and at its headquarters in Torrance, Calif., in Harman’s district.

in 2007, with new privacy filters in place, the TSA began a trial of millimeter-wave and backscatter machines at several major airports, after which the agency opted to go with the millimeter-wave machines. The agency said health concerns weren’t a factor.

In its statement, Orbcomm suggested that i

had enough access to the satellite in less than four days in orbit to validate the performance of its major subsystems.

Orbcomm said that, had its satellite been the primary payload on SpaceX’s Oct. 7 flight, the mission would have been a success

OG2 satellite bus systems including power, attitude control, thermal and data handling were also tested to verify proper operation

The solar array and communications antenna deployments were successful

Orbcomm requested that SpaceX carry one of their small satellites

few hundred pounds, vs. Dragon at over 12,000 pounds

on this flight so that they could gather test data before we launch their full constellation next year.

The higher the orbit, the more test data they can gather, so they requested that we attempt to restart and raise altitude

NASA agreed to allow that, but only on condition that there be substantial propellant reserves, since the orbit would be close to the space station

Orbcomm understood from the beginning that the orbit-raising maneuver was tentative

They accepted that there was a high risk of their satellite remaining at the Dragon insertion orbit.

GLACIER, or General Laboratory Active Cryogenic ISS Experiment Refrigerator, is primarily used to preserve science samples that require temperatures between minus 301 and 39 degrees Fahrenheit (minus 160 and 4 degrees Celsius

The brand of ice cream flying in the Dragon's GLACIER is Blue Bell Creameries, a Texas dairy that has a strong fan base in Houston

Blue Bell ice cream has been flown to the space station before. The creamery's cups first launched to the orbiting laboratory in 2006 on board the space shuttle Atlanti

prominent