Astronomy Picture Of the Day (APOD)Framed by Clouds
Last Sunday's fading evening twilight featured a young crescent Moon along the western horizon. The young Moon also shared the sky with the lovely Pleiades star cluster and wandering planet Mercury. Framed by clouds in this serene skyscape from Selsey, UK, a similar twilight scene was visible around the globe.
GRB 090423: The Farthest Explosion Yet Measured
An explosion so powerful it was seen clear across the visible universe was recorded in gamma-radiation last week by NASA's orbiting Swift Observatory. Farther than any known galaxy, quasar, or optical supernova, the gamma-ray burst recorded last week was clocked at redshift 8.2, making it the farthest explosion of any type yet detected.
NGC 4565: Galaxy on the Edge
Is our Galaxy this thin? We believe so. Magnificent spiral galaxy NGC 4565 is likely similar to our own spiral galaxy, but viewed edge-on from far away. Also known as the Needle Galaxy...
Prometheus Creating Saturn Ring Streamers
What's causing those strange dark streaks in the rings of Saturn? Prometheus. Specifically, an orbital dance involving Saturn's moon Prometheus keeps creating unusual light and dark streamers in the F-Ring of Saturn. Now Prometheus orbits Saturn just inside the thin F-ring, but ventures into its inner edge about every 15 hours.
NGC 4676: When Mice Collide
These two mighty galaxies are pulling each other apart. Known as "The Mice" because they have such long tails, each spiral galaxy has likely already passed through the other. They will probably collide again and again until they coalesce.
Dark Markings of the Sky
Based on wide field photographs, American astronomer Edward Emerson Barnard cataloged the dark markings of the sky in the early 20th century. Barnard's markings are dark nebulae, interstellar clouds of obscuring gas and dust.
Moon and Morning Star
Wednesday, the Moon and Venus rose together in early morning skies. Even through clouds, both show off a lovely crescent in this well-composed skyscape from Rutherford College, North Carolina, in the eastern US. Farther west, North American skygazers could also witness the Moon passing in front of Venus.
Blown by fast winds from a hot, massive star, this cosmic bubble is huge. Cataloged as Sharpless 308 it lies some 5,200 light-years away in the constellation Canis Major and covers over 2/3 degree on the sky (compared with 1/2 degree for the Full Moon).
Sky Panorama Over Lake Salda
As midnight approached, a spectacular sky appeared. Such was the case last month from the shore of Lake Salda in southwestern Turkey. In the above night sky panorama, rocky sand covers the foreground, while building lights are visible across the lake.
Global Warming Predictions
How much will the Earth's surface warm up over the lives of our children? No one is sure. Compared to the past 100 million years, the Earth is currently enduring a relative cold spell, possibly about four degrees Celsius below average.