Eye In The Sky

Astronomy Picture of the Day

Stickney Crater

Stickney Crater
Credit: HiRISE, MRO, LPL (U. Arizona), NASA
Stickney Crater, the largest crater on the martian moon Phobos, is named for Chloe Angeline Stickney Hall, mathematician and wife of astronomer Asaph Hall.

Asaph Hall discovered both the Red Planet's moons in 1877.

Astronmomy Picture of the Day

How Cool Is Outer Space?

Trifid Pillars & Jets
Credit: J. Hester (Arizona St. U) et al., WFPC2, HST, NASA

Explanation: Dust pillars are like interstellar mountains. They survive because they are more dense than their surroundings, but they are being slowly eroded away by a hostile environment. Visible in the above picture is the end of a huge gas and dust pillar in the Trifid Nebula, punctuated by a smaller pillar pointing up and an unusual jet pointing to the left. The pink dots are newly formed low-mass stars. A star near the small pillar's end is slowly being stripped of its accreting gas by radiation from a tremendously brighter star situated off the above picture to the upper right. The jet extends nearly a light-year and would not be visible without external illumination. As gas and dust evaporate from the pillars, the hidden stellar source of this jet will likely be uncovered, possibly over the next 20,000 years.

Hubble Captures Galaxies's Gravity Dance

Two galaxies perform an intricate dance in this new Hubble Space Telescope image. The galaxies, containing a vast number of stars, swing past each other in a graceful performance choreographed by gravity. CLick on image for larger view.

via Spulch and Space Telescope

Hubble Captures Veil Nebula

The Hubble Space Telescope has caught just-released snapshots of the 1500-light-year-distant Veil Nebula, the remnants of a supernova, or star explosion, that happened a few as five thousand years ago.

The Hubble close-ups reveal the rope-like filaments of gas in the nebula, which resulted from enormous amounts of dusty debris plowing into gaseous surroundings. Thicker filaments of material result from viewing the supernova’s shock wave edge-on, while more wispy and diffuse views correspond to a face-on view of other parts of the shock wave from Earth.

Link

Quadruple Sunsets Possible

Planets may be present in a quadruple star system 150 light years from Earth, according to Spitzer Space Telescope observations.

The system, called HD 98800, consists of two pairs of stars in which the partners in each pair orbit one another closely. The pairs themselves travel around each other on a very elongated path. A dusty disc was already known to surround one of the pairs of stars.

An observer watching from the surface of the planet could witness dual sunsets and sunrises involving the central pair of stars, Furlan says. The pair would appear as twin suns, both tinged orange because they are a bit less massive and cooler than the Sun. The other pair, being more distant, would merely look like bright stars.

Link New Scientist
via Spluch

Dark Matter

Today scientists announced that they had mapped a ring of dark matter around a galaxy cluster utilizing gravitational distortions observed in photographs taken by the Hubble space telescope.

This is a groundbreaking discovery, since for decades scientists had theorized that the bulk of the Universe is held together by dark matter, and that this matter could not be observed since it neither emits nor reflects light.

Read more at the Bad Astronomy Blog.

Amazing Hubble Photo

NGC 6302: Big, Bright, Bug Nebula
Credit: A. Zijlstra (UMIST) et al., ESA, NASA

Explanation: The bright clusters and nebulae of planet Earth's night sky are often named for flowers or insects, and NGC 6302 is no exception. With an estimated surface temperature of about 250,000 degrees C, the central star of this particular planetary nebula is exceptionally hot though -- shining brightly in ultraviolet light but hidden from direct view by a dense torus of dust. Above is a dramatically detailed close-up of the dying star's nebula recorded by the Hubble Space Telescope. Cutting across a bright cavity of ionized gas, the dust torus surrounding the central star is in the upper right corner of this view, nearly edge-on to the line-of-sight. Molecular hydrogen has recently been detected in this hot star's dusty cosmic shroud. NGC 6302 lies about 4,000 light-years away in the arachnologically correct constellation Scorpius.

via Astronomy Picture of the Day

Possible seas discovered on Saturn moon

Scientists have discovered what appear to be sea-size bodies of liquid, probably methane or ethane, on the surface of Saturn's largest moon, including one about as big as Montana.

Cassini's camera last month spied a large, irregular feature stretching 680 miles long with a surface area similar to Montana's, or to Asia's landlocked Caspian Sea. Its radar instrument swept over the feature's northern tip and determined that it likely contains liquid methane or ethane because of its smooth appearance.

The spacecraft also discerned another body one-fifth the size of Titan's "Caspian Sea." With a surface area of about 46,000 square miles, it is larger than Lakes Superior and Ontario combined, scientists said.

USA Today

Saturn from Above

Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA

Explanation: This image of Saturn could not have been taken from Earth. No Earth based picture could possibly view the night side of Saturn and the corresponding shadow cast across Saturn's rings. Since Earth is much closer to the Sun than Saturn, only the day side of the planet is visible from the Earth. In fact, this image mosaic was taken in January by the robotic Cassini spacecraft now orbiting Saturn. The beautiful rings of Saturn are seen in full expanse, while cloud details are visible near the night-day terminator divide.

via Astronomy Picture of the Day