U.S. STUDENTS FLOCK TO GRADUATE SCIENCE PROGRAMS
by Jeffrey Mervis on 1 June 2012
The data are strangely absent from most discussions about the inadequacies of science education in the United States. But a new report from the National Science Foundation (NSF) finds that the number of Americans pursuing advanced degrees in science and engineering has risen sharply over the past decade and stands at an all-time high.
U.S. politicians are constantly complaining that the nation's system of higher education isn't producing the high-tech workforce needed to keep the country's economy competitive. And one big reason, they say, is a lack of student interest in the so-called STEM (science, technology, engineering, and mathematics) fields. But the numbers, at least for graduate education, tell a different story.
An NSF analysis released today shows that graduate enrollment in science and engineering programs at U.S. institutions increased 35% from 2000 to 2010, to a record 556,532. What experts regard as an even more sensitive barometer of student interest has shot up even faster, with first-time, full-time graduate enrollment in STEM programs registering a 50% increase over the decade.
A closer analysis of the numbers, which come from NSF's annual Survey of Graduate Students and Postdoctorates in Science and Engineering, offers still more encouraging demographic news. Although foreign students make up 30% of the total enrollment in U.S. graduate science and engineering programs, and while they constitute a majority in several fields, their slice of the overall pie has not grown in the past decade. Rather, the pools of U.S. citizens and those with temporary visas each grew by 35%.
Individuals and organizations trying to attract more women and minorities into careers in science and engineering also have cause for celebration. The number of female graduate students in STEM fields grew by 40% over the decade, outpacing the 30% growth rate for men. Likewise, the growth of Hispanic and African-American STEM graduate students rose by 65% and 50%, respectively, outpacing the 35% growth for the overall population.
The author of the report, NSF's Kelly Kang, points out that the increasing interest in STEM degrees among U.S. students is not a new phenomenon. She says her analysis simply provides additional evidence of a decade-long trend.
That is certainly true. On the other hand, it can take a long time for politicians to abandon arguments based on outdated numbers and to embrace new data that make the opposite case. The latest information from NSF has the potential to change minds and, in turn, influence the debate about preparing the next generation of U.S. scientists and engineers.
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SWISS WANT TO BUILD A SATELLITE THAT REMOVES SPACE LITTER
by Daniel Clery on 15 February 2012
Space researchers in Switzerland are seeking funding to build a spacecraft that will home in on a redundant satellite, grab it, and drag it down to burn up when reentering the atmosphere. The idea is to stem the tide of debris that is littering space around the Earth.
Researchers at the Swiss Space Center at the École Polytechnique Fédérale de Lausanne have been working on the necessary technology for 3 years, says Swiss Space Center Director Volker Gass. The experimental probe's potential first target would be Switzerland's first space mission, a picosatellite called SwissCube that was launched in 2009. Gass says the spacecraft, dubbed CleanSpaceOne, would cost an estimated $11 million to build and launch and could be ready between 2015 and 2017.
Space junk is an increasing problem for space agencies. It ranges in size from entire satellites that are uncontrolled to rocket stages or fragments from collisions. NASA tracks some 16,000 objects larger than 10 cm, but there are many more fragments smaller than this. Despite the objects' small size, their velocity gives them the ability to do a lot of damage.
In 2009, an operational Iridium mobile communications satellite collided with a redundant Russian communications satellite at a relative speed of more than 42,000 km per hour. NASA estimated that the crash created as many as 1000 new fragments larger than 10 cm and many smaller ones. The debris can also put astronauts at risk. The International Space Station often has to maneuver to avoid space junk, with its residents sometimes taking shelter in the escape capsule.
CleanSpaceOne is designed to take down larger pieces of junk. The semiautomatic probe will need a sophisticated guidance and control system to insert itself into the right orbit to reach a target moving at 28,000 km/h. Cameras will be used to optically identify the target satellite and ion microthrusters will ease the probe right up to it. The Swiss researchers are investigating biologically inspired gripping mechanisms to snag the target, such as one that has tentacles like a sea anemone.
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Once captured, the combined object will have a new center of gravity and may be spinning in an uncontrolled way. The probe has to stabilize the trajectory and then guide itself onto a curve toward the atmosphere. "There are quite some challenges," says Gass.
Gass envisages a whole family of ready-made craft able to de-orbit different sorts of satellites. Another approach would be to sell "de-orbit kits" to be built into new satellites so that they could bring themselves down at the end of their useful lives. "Switzerland is a country that likes to keep things clean," Gass says. "So we decided to first get our own satellite down."
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