SUNSET: 
Brown-Dwarf Binary May Challenge Theories
A tightly bound pair of sub-stars in Orion may throw models into disarray.
Amateurs Help Discover Exoplanet
Artist David A. Aguilar depicts the exoplanet that professional and amateur astronomers discovered recently by gravitational microlensing. The planet is about 3 times as massive as Jupiter, and it orbits its host star (upper right) at about 3 astronomical units. The moon is hypothetical.Courtesy David A. Aguilar (CfA). In a…
12 New Saturnian Moons
The circled white dot is one of 12 newly discovered Saturnian moons. This satellite, temporarily designated S/2004 S11, is about 6 kilometers (4 miles) across.Courtesy David Jewitt / Scott Sheppard / Jan Kleyna. There was once a time when the discovery of a single new moon was a landmark event…
"First Exoplanet" Image Confirmed
This infrared image resolves 2M 1207 into a close pair of objects, one of them 100 times brighter than the other. Astronomers infer that their masses are 25 and 5 Jupiter masses, which would make them a brown dwarf and a planet, respectively. Both are glowing with heat left over…
An Exo-Asteroid Belt
This artist's concept shows a massive asteroid belt in orbit around a star with an age and luminosity similar to our Sun. The Spitzer Space Telescope has apparently found such a belt around the star HD 69830.Courtesy NASA / JPL-Caltech / Tim Pyle (SSC). Astronomers have enjoyed considerable success in…
The Milky Way's New Neighbor
Many of the faint stars in this image belong to the newly discovered Ursa Major dwarf galaxy. The 5-by-5-arcminute image, taken with the 3.5-meter telescope at the Apache Point Observatory, covers the inner half of the galaxy.Courtesy Andrew West (University of Washington) / Apache Point Observatory. The Milky Way's family…
Exoplanets: The Heat Is On
Not a pleasant place to be: a hot Jupiter hovers near its parent star. This composite image combines art of an exoplanet and a TRACE satellite image of magnetic loops of hot gas on the Sun.Courtesy David Aguilar (CfA) / TRACE / NASA. For the first time ever, astronomers have…
The Most Massive Stars
The Arches Cluster is the most spectacular young star cluster in the Milky Way Galaxy. Located about 25,000 light-years away near the galactic center, it is home to about a dozen stars with more than 100 solar masses. The high resolution of this Hubble Space Telescope image, taken by the…
Hans Bethe
(1906—2005)
Hans Bethe earned the Nobel Prize for determining how stars generate energy. This research remains one of the greatest contributions to our understanding of the universe.Courtesy Cornell University. Hans Bethe, one of the towering figures of 20th-century astrophysics, died on Sunday, March 6th, at his home in Ithaca, New York,…
Einstein Passes New Tests
A binary pulsar system provides an excellent laboratory for testing some of the most bizarre predictions of general relativity. The two pulsars in the J0737-3039 system are actually very far apart compared to their sizes. In a true scale model, if the pulsars were the sizes of marbles, they would…
The Brightest Blast
This illustration, which is based on the latest scientific thinking, represents how a magnetar might appear if we could view it up close with X-ray vision. But this is not something anyone would want to do. Magnetars are neutron stars with magnetic fields so powerful that they could kill a…
A Flurry of Exoplanet Discoveries
This artist's concept depicts a disk of gas and dust around a young brown dwarf. Low-mass disks like this should be capable of forming planetary systems with perhaps one gas giant and several Earth-size bodies.Courtesy NASA / JPL / Caltech. Discoveries of extrasolar planets are coming so fast and furious…
Astro Image in the News:
The Real Rhea
Courtesy NASA / JPL / Space Science Institute. Cassini's narrow-angle camera acquired this image of Saturn's moon Rhea on January 16th. With a diameter of 1,528 kilometers (949 miles), Rhea edges out Iapetus for being Saturn's second largest satellite, though it is less than half the size of Earth's Moon.…
Opportunity Finds an Iron Meteorite
Tests have confirmed that the basketball-size Heat Shield Rock, imaged here by Opportunity's panoramic camera, is a meteorite composed primarily of iron and nickel. Note the small 'blueberries' that surround the meteorite.Courtesy NASA / JPL / Cornell University. On December 21, 2004, the Mars Exploration Rover Opportunity arrived at its…
Hooray for Huygens!
As Huygens descended through the atmosphere of Titan, the probe recorded this system of stubby, interconnected channels leading to an apparent shoreline. The scene is about 5 kilometers (3 miles) wide.Courtesy ESA/NASA/University of Arizona. Move over, Mars! Saturn's large moon Titan is now the most distant world touched by the…
Intriguing Iapetus
This Cassini image shows Iapetus's leading hemisphere, most of which is as dark as an asphalt parking lot. Scientists were amazed to find a giant ridge girdling at least one-third of the moon's circumference. The highest peaks along the ridge are about 20 kilometers (12 miles) high, which rivals Mars's…
Amateurs Detect Possible Exoplanet Ringlike Structure
This artist conception depicts a Jupiter-size planet transiting its host star at a close distance, as is the case with TrES-1. Amateur astronomer observations suggest that the planet might be surrounded by a cloud or torus of particles.S&T illustration by Steven A. Simpson. Amateur astronomers may have discovered a ringlike…
Making New Friends
This mosaic combines five Cassini images of Saturn's moon Dione. The moon's heavily cratered surface and grooved terrain are evident. The scale is 0.9 kilometer per pixel.Courtesy NASA / JPL / Space Science Institute. Scientists are beginning to digest a plethora of new images and data following Cassini's successful flybys…
Bush Fires Threaten "The Dish"
Smoke from a bush fire billows around the Parkes radio telescope in Australia. Fortunately, the observatory was not damaged.Photo copyright: CSIRO / John Sarkissian. Over the past several days, bush fires raged within 1 kilometer (0.6 mile) of the 64-meter Parkes radio telescope, located in New South Wales, Australia. Besides…
Astro Image in the News:
Surreal Saturn Portrait
Courtesy NASA / JPL / Space Science Institute. As Cassini recedes from Saturn after completing its first orbit, the spacecraft's narrow-angle camera is returning mesmerizing images of the planet, rings, and moons. This new image showcases curving shadows cast by the rings on Saturn's northern hemisphere. The small satellite Mimas…
