Is Earth Pelted by Space Snowballs?

A NASA satellite has captured evidence of house-sized comets smashing into Earth's atmosphere.

Spanish fossils enter human ancestry fray

Fossils about 800,000 years old have been assigned to a new Homo species, which may have been the last common ancestor of modern humans and Neandertals.

Enzyme rare in adults may signal cancers

Telomerase, an enzyme rarely seen in the healthy human body, may be a warning sign of cancer.

Where there's smoke, there's germination

Trace nitrogen gases in smoke trigger germination of wildflower seeds in fire-prone chaparral.

DNA doubles in a four-stranded huddle

Two closed loops of single-stranded DNA can form a novel, four-stranded structure.

A giant step toward creating better fats

Engineering novel enzymes may lead to crops that manufacture low-fat margarines and nylon feedstocks.

News flash! A bust goes the distance

After 25 years of debating whether gamma-ray bursts come from within our galaxy, astronomers have evidence that one of these energetic flashes originated outside the Milky Way.

Research Notes:

Biomedicine

Fidgety babies equals healthy babies

Videotaping the movements of premature babies indicate whether they have brain damage.

Betel nuts tasting a bit metallic?

Betel nuts contain copper, which may lead to mouth cancer in people chew them.

New cold sore cream on the market

The antiviral cream penciclovir speeds healing of cold sores.

Earth Science

Making a prisoner out of methane

Oceanographers for the first time fabricated an elusive form of solid methane in its natural environment.

Earth's temperature grows more uniform

The temperature difference between the tropics and poles has decreased over the last century.

Material Science

A magnet for a future atom smasher

Scientists have constructed the strongest dipole magnet, which may one day be used in a high-energy particle accelerator.

Stresses and strains on diamond

Diamond, long thought to be rigid, can bend a surprising amount under very high pressures.

Mathematics

Assessing irrational irregularity

A novel measure of irregularity indicates that the digits of pi are closer to being randomly distributed than those of other irrational numbers, such as the square root of 3.

Cracking a record number

A worldwide effort determined the two prime factors of a 167-digit number, setting a record for the largest number yet factored.

Articles:

Is Science Talent Squandered?

How future scientists can come undone

A dry experience with science in the first years of college saps the interest of many talented would-be scientists.

Sphinx of Fats

Some lipids, wallflowers for a century, show therapeutic promise

A ubiquitous but little known family of fats appears to help fight disease.

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