2011 Science News of the Year: Atom & Cosmos

Not so fast, neutrinos

News of particles zipping along faster than light (SN: 10/22/11, p. 18) was met with universal skepticism — including from the physicists in Italy who reported the results. But the Gran Sasso National Laboratory’s OPERA team hasn’t found any source of error that could explain how the neutrinos appeared to shave 60 nanoseconds off of light-speed travel time while covering the 730 kilometers from the CERN physics laboratory near Geneva to Gran Sasso.

Einstein’s special theory of relativity says such speeds shouldn’t be attainable. And even if they were, the neutrinos would have shed observable energy during flight, report physicists at Boston University (SN: 11/5/11, p. 10). Critics suggest that at the different locales gravity may have pulled on the clocks with different strengths, causing the timekeepers to tick at different rates. Or some of the particles in the neutrino bunches could have started the trip earlier than thought.

Faced with these criticisms, the OPERA team has used shorter, sharper pulses of particles to check the results. The researchers say the findings still stand, but other large neutrino projects plan to repeat the experiment. — Devin Powell

Still shining  Some of the universe’s first stars may still be shining in the Milky Way, 13.4 billion years after forming, disputing the prevailing view that early stars died out quickly (SN: 2/26/11, p. 18).

Peter Nugent and the Palomar Transient Factory

Boom, then zoom Telescopes capture a white dwarf star going supernova just 21 million light-years away (SN: 9/24/11, p. 5).

Rocks of life  Life-related chemicals are found in nearly a dozen meteorites, the strongest evidence yet that space rocks contain the building blocks of DNA and could have delivered them to Earth (SN Online: 8/10/11).

Superhot solution  NASA’s Solar Dynamics Observatory spots fountainlike jets of hot gas that shoot into the sun’s outer atmosphere, possibly explaining why it is millions of degrees hotter than the solar surface (SN: 1/29/11, p. 12).

Good-bye shuttle  Three decades after the first launch, the space shuttle program ends its run (SN: 6/18/11, p. 20). NASA also announces its pick of designs for a heavy-lift rocket to take next-gen astronauts into space.

Solar doldrums  Scientists predict that the sunspot cycle that began in early 2008 will be the weakest in 200 years (SN: 3/26/11, p. 5). Studies also suggest that a period of reduced solar activity could help cool the climate (SN: 7/16/11, p. 12).

Exoplanet bonanza A bevy of exoplanets are added to the growing list, including the first confirmed rocky planet beyond the solar system (SN: 2/12/11, p. 12) and a planet with a radius 2.4 times larger than Earth’s parked firmly within its star’s life-friendly zone (SN: 12/31/11, p. 11).

Last words The Fermi National Accelerator Laboratory’s Tevatron shuts down after a quarter century (SN: 9/24/11, p. 22). Before the closing, scientists discover the Xi-sub-b particle, predicted by the standard model of particle physics (SN: 8/27/11, p. 14).

Lurking lakes  Europa’s chaotic surface features signal the presence of large pockets of liquid water tucked into the Jupiter moon’s rock-hard ice, scientists report (SN: 12/17/11, p. 5).

Fluid situation  Analyses of mineral data hint that Mars’ ancient surface may have been cold and frigid, with fluids appearing only beneath the planet’s ruddy sands (SN: 12/3/11, p. 5).

Mercury close-up  NASA’s MESSENGER spacecraft returns the first images ever taken by a probe orbiting Mercury, showing parts of the south and north polar terrains (SN Online: 3/30/11).

Dark check  Astronomers looking at distortions of microwaves left over from the Big Bang independently confirm the existence of dark energy (SN: 8/13/11, p. 18).

Crabby flares  The Crab Nebula hurls gamma-ray flares more energetic and five times brighter than any previously recorded, challenging theories about how the heavens accelerate charged particles (SN: 6/4/11, p. 10).

Crash course  The Genesis probe finds that, compared with the sun, the Earth is enriched in two types of oxygen and one of nitrogen (SN: 7/16/11, p. 5).

Superdupernova  A new class of supernovas emit much of their light at ultraviolet wavelengths and show no traces of hydrogen (SN: 7/2/11, p. 10).

Probe payoff  Gravity Probe B confirms that the Earth drags spacetime as it rotates, an effect known as “frame dragging” that is predicted by Einstein’s general theory of relativity (SN: 5/21/11, p. 5).

Hints of the Higgs Two experiments at the Large Hadron Collider find hints of the elusive Higgs boson, the last missing piece in particle physics’ standard model (SN: 12/31/11, p. 10).