Astronomy Picture of the Day

2011-04-19

A symphony of planet-wide observations began abruptly on March 28 when the Earth-orbiting Swift satellite detected a burst of high-frequency gamma-rays from GRB 110328A. When the same source flared again after a 45 minute pause it was clear this ...

2011-04-18 Burrell Durrant Hifle Design & Direction Limited

What visual effects are depicted in this video? The effects were created by BDH for the BBC television show Wonders of the Universe, but are unlabeled in this version. Even so, some stills in the video are easily identified, such as the Hubble ...

2011-04-17 Roddy Mackenzie

What would it be like to stand atop the tallest mountain on Earth? To see a full panoramic vista from there, scroll right. Visible are snow peaked mountains near and far, tremendous cliffs, distant plateaus, the tops of clouds, and a dark blue ...

2011-04-16 Mark Hanson

This telescopic close-up shows off the otherwise faint emission nebula IC 410 in striking false-colors. It also features two remarkable inhabitants of the cosmic pond of gas and dust above and left of center, the tadpoles of IC 410. The picture ...

2011-04-15

Big, beautiful spiral galaxy M101 is one of the last entries in Charles Messier's famous catalog, but definitely not one of the least. About 170,000 light-years across, this galaxy is enormous, almost twice the size of our own Milky Way galaxy. ...

2011-04-14

Dust clouds and embedded newborn stars glow at infrared wavelengths in this tantalizing false-color composition from WISE, the Wide-field Infrared Survey Explorer. The cosmic canvas features one of the closest star forming regions, part of the ...

2011-04-13

What if you could see the huge radio jets of Centaurus A rising? The Cen A radio jets are not only over a million light years long, they occupy an angular area over 200 times greater than the full Moon in Earth's sky. The jets are expelled by a ...

2011-04-12

On April 12th, 1961, Soviet cosmonaut Yuri Alexseyevich Gagarin became the first human in space. His remotely controlled Vostok 1 spacecraft lofted him to an altitude of 200 miles and carried him once around planet Earth. Commenting on the first ...

2011-04-11 Robert Arn

What would a sunrise look like on another world? So far, humanity has only recorded sunrises on Mars and Earth, but it is fun to wonder what they would look like on planets known and yet unknown. Planets far from their parent star would record ...

2011-04-10

It was a quiet day on the Sun. The above image shows, however, that even during off days the Sun's surface is a busy place. Shown in ultraviolet light, the relatively cool dark regions have temperatures of thousands of degrees Celsius. Large ...