Heavens

Twenty-four unusual stars, 18 of them newly discovered, have been observed in new Hubble telescope images. The stars are white dwarfs, a common type of dead star, but they are odd because they are made of helium rather than the usual carbon and oxygen.This is the first extensive sequence of helium-core white dwarfs to be observed in a globular cluster, a dense swarm of some of the oldest stars in our galaxy.

(Boston) – Researchers from Boston University School of Medicine (BUSM) have found that among preteens, the use of photographs to measure ultraviolet (UV) exposure, could motivate them to improve sun protection practices and limit number of sunburns. These findings appear in the April 2009 issue of the Journal of the Dermatology Nurses' Association.

Researchers at North Carolina State University have used a mathematical model that allows them to get a clearer picture of the galaxy's youngest supernova remnant by correcting for the distortions caused by cosmic dust. Their new data provides evidence that this remnant is from a type Ia supernova - the explosion of a white dwarf star - and raises questions about the ways in which magnetic fields affect the generation of the remnant's cosmic ray particles.

GREENBELT, Md. - An international team of astronomers has used the world's biggest radio telescope to look deep into the brightest galaxies that NASA's Fermi Gamma-ray Space Telescope can see. The study solidifies the link between an active galaxy's gamma-ray emissions and its powerful radio-emitting jets.

"Now we know for sure that the fastest, most compact, and brightest jets we see with radio telescopes are the ones that are able to kick light up to the highest energies," said Yuri Kovalev, a team member at the Max Planck Institute for Radio Astronomy in Bonn, Germany.

Pasadena, CA—Using information from a suite of telescopes, astronomers have discovered a mysterious, giant object that existed at a time when the universe was only about 800 million years old. Objects such as this one are dubbed extended Lyman-Alpha blobs; they are huge bodies of gas that may be precursors to galaxies. This blob was named Himiko for a legendary, mysterious Japanese queen. It stretches for 55 thousand light years, a record for that early point in time. That length is comparable to the radius of the Milky Way's disk.

"Asteroids seem to get a 'sun tan' very quickly," says lead author Pierre Vernazza. "But not, as for people, from an overdose of the Sun's ultraviolet radiation, but from the effects of its powerful wind."

It has long been known that asteroid surfaces alter in appearance with time — the observed asteroids are much redder than the interior of meteorites found on Earth1 — but the actual processes of this "space weathering" and the timescales involved were controversial.

Some parasites can exert a moderating effect on the immune system, perhaps reducing the risk of developing immune dysfunctions like asthma, allergies and some forms of arthritis. Researchers writing in the open access journal BMC Biology studied the effects of several parasites on the immune activity of wild wood mice, finding that louse infestation was associated with a reduced readiness to mount an immune response.

Over the past 19 years Hubble has taken dozens of exotic pictures of galaxies going "bump in the night" as they collide with each other and have a variety of close encounters of the galactic kind. Just when you thought these interactions couldn't look any stranger, this image of a trio of galaxies, called Arp 194, looks as if of the galaxies has sprung a leak. The bright blue streamer is really a stretched spiral arm full of newborn blue stars. This typically happens when two galaxies interact and gravitationally tug at each other gravitationally.

"The holy grail of current exoplanet research is the detection of a rocky, Earth-like planet in the 'habitable zone' — a region around the host star with the right conditions for water to be liquid on a planet's surface", says Michel Mayor from the Geneva Observatory, who led the European team to this stunning breakthrough.

Making choices is tough, especially in a competitive retail environment. A new study in the Journal of Consumer Research sheds some light on the processes consumers use to make choices among multiple options.

An international team  have discovered one of the coolest sub-stellar bodies ever found outside our own solar system, orbiting the red dwarf star Wolf 940, some 40 light years from Earth.

The object is thought to have formed like a star, but has ended up looking more like Jupiter. It is roughly the same size, despite being between 20 and 30 times as heavy, and when the infrared spectral "fingerprints" of the two objects are compared, their resemblance is striking.

Using NASA’s Spitzer Space Telescope, an international team of astronomers have found that at least 1 in 100 white dwarf stars show evidence of orbiting asteroids and rocky planets, suggesting these objects once hosted Solar Systems similar to our own. Team member Dr Jay Farihi of the University of Leicester will present this discovery on Monday 20th April at the European Week of Astronomy and Space Science conference at the University of Hertfordshire.

Astronomers have announced plans to build an ultra-stable, high-precision spectrograph for the Science and Technology Facilities Council's 4.2-m William Herschel Telescope (WHT - part of the Isaac Newton Group or ING on La Palma) in an effort to discover habitable Earth-like planets around other stars. Dr Ian Skillen of the ING will present the new High Accuracy Radial-velocity Planet Search – New Earths Facility (HARPS-NEF) spectrograph in a poster on Monday 20th April at the European Week of Astronomy and Space Science conference at the University of Hertfordshire.

'Sigmoids' are S-shaped structures found in the outer atmosphere of the Sun (the corona), seen with X-ray telescopes and thought to be a crucial part of explosive events like solar flares. Now a group of astronomers have developed the first model to reproduce and explain the nature of the different stages of a sigmoid’s life.

New Rochelle, April 16, 2009–Solar energy and winds, collisions with asteroids and comets, and changing magnetic fields have all altered the environment of Mars, a planet that may have been able to support life during its history, as documented in a special collection of papers published in the current issue of Astrobiology, a peer-reviewed journal published by Mary Ann Liebert, Inc. This Special Paper Collection is available free online at www.liebertpub.com/ast