Chefs have long used a simple trick to differentiate between a raw and hard-boiled egg. By spinning an egg and watching how it behaves when the spin is disrupted, it's easy to tell whether its interior is solid or liquid.

Applying a similar test to the planet Mercury, astronomers have found strong evidence that the planet closest to the sun has a fluid core. The research, led by Jean-Luc Margot, assistant professor of astronomy at Cornell, appears this week on the Web site of the journal Science.

New observations by the NASA/ESA Hubble Space Telescope have overturned conventional ideas about the early life of some massive globular clusters, showing that they can go through several periods of intense stellar formation rather than the previously accepted single burst. The analysis of Hubble data from the massive globular cluster NGC 2808 provides evidence that star birth occurred over three generations early in the cluster's life.

This NASA/ESA Hubble Space Telescope image of a dense swarm of stars shows the central region of the globular cluster NGC 2808. Astronomers were surprised when Hubble spied three generations of cluster stars.

Want to know if the International Space Station is over you right now? You can view the location of ESA's Earth-orbiting spacecraft and other ESA-related missions in real-time via a new tracking site.

Credits: ESA

Astronomers have discovered the most Earth-like planet outside our Solar System to date, an exoplanet with a radius only 50% larger than the Earth and capable of having liquid water. Using the ESO 3.6-m telescope, a team of Swiss, French and Portuguese scientists discovered a super-Earth about 5 times the mass of the Earth that orbits a red dwarf, already known to harbour a Neptune-mass planet. The astronomers have also strong evidence for the presence of a third planet with a mass about 8 Earth masses.

Artist's impression of the system of three planets surrounding the red dwarf Gliese 581.

NASA's Solar TErrestrial RElations Observatory (STEREO) satellites have provided the first three-dimensional images of the sun. For the first time, scientists will be able to see structures in the sun's atmosphere in three dimensions. The new view will greatly aid scientists' ability to understand solar physics and there by improve space weather forecasting. This web page contains 3-D anaglyph video and images. This 3-D video can be seen with red and cyan + 3-D paper glasses.

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Warm gas escaping from the clutches of enormous black holes could be the key to a form of intergalactic 'pollution' that made life possible, according to new results from ESA. The gas that escapes contains elements heavier than hydrogen or helium and is positively ionized, including carbon, the essential element for life on Earth.

Black holes are not quite the all-consuming monsters depicted in popular culture.

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There's a "First Light Fiesta" in the works at Mt. Hopkins near Amado, Ariz. And Iowa State University astrophysicists will be among those enjoying the celebration of a new telescope system and all the science it will produce.

Iowa State University astrophysicists designed and built four of these cameras for the VERITAS gamma ray telescope system. Each camera contains 500 tube-shaped photo detectors. Credit: Photo contributed by Frank Krennrich/Iowa State University

 

Giovanna Tinetti is an expert on detecting signs of life across interstellar space. She has worked at JPL, Caltech and the Institut d’Astrophysique de Paris, and has just won an Aurora Fellowship to pursue her research on biosignatures at University College, London. We caught up with her as she made an exploratory visit to the city that will be her home for the next three years.

How do you describe yourself?

A new theoretical thermometer built from heavy-duty mathematics and computer code suggests that the surfaces of certain neutron stars run significantly hotter than previously expected. Hot enough, in fact, to at least partially answer an open question in astrophysics -- how to explain the observed frequency of ultra-violent explosions known as superbursts that sometimes ignite on such stars' surfaces?

Neutron star accreting matter from a red giant star. The red giant (on the upper right) is expanding and dumping material onto the neutron star. This material forms a disk and then finally falls to the neutron star surface. Credit: Tony Piro, U.C. Berkeley

Cluster is providing new insights into the working of a ‘space tsunami’ that plays a role in disrupting the calm and beautiful aurora, or northern lights, creating patterns of auroral dances in the sky.

The image to the left is the typical appearance of the aurora before a magnetic substorm. During a substorm, the single auroral ribbon may split into several ribbons (centre) or even break into clusters that race north and south (right). Credits: Jan Curtis