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Hubble Captures a Rare Eclipse on Uranus

Tuesday, September 12, 2006

Uranus Eclipse
Arial traverses Uranus
click for larger image

This NASA Hubble Space Telescope image is a never-before-seen astronomical alignment of a moon traversing the face of Uranus, and its accompanying shadow. The white dot near the center of Uranus’ blue-green disk is the icy moon Ariel. The 700-mile-diameter satellite is casting a shadow onto the cloud tops of Uranus. To an observer on Uranus, this would appear as a solar eclipse, where the moon briefly blocks out the Sun as its shadow races across Uranus’s cloud tops. Though such "transits" by moons across the disks of their parents are commonplace for some other gas giant planets, such as Jupiter, the satellites of Uranus orbit the planet in such a way that they rarely cast shadows on the planet's surface. Uranus is tilted so that its spin axis lies nearly in its orbital plane. The planet is essentially tipped over on its side. The moons of Uranus orbit the planet above the equator, so their paths align edge-on to the Sun only every 42 years. This color composite image was created from images at three wavelengths in near infrared light obtained with Hubble’s Advanced Camera for Surveys on July 26, 2006. Dr. Kathy Rages, of the SETI Institute, made the identification of the bright spot as Ariel.

Credit: NASA, ESA, L. Sromovsky (University of Wisconsin, Madison), H. Hammel (Space Science Institute), and K. Rages (SETI)

Orion's Inner Beauty

Tuesday, August 15, 2006

Sword of Orion

This infrared image from NASA's Spitzer Space Telescope shows the Orion nebula, our closest massive star-making factory, 1,450 light-years from Earth. The nebula is close enough to appear to the naked eye as a fuzzy star in the sword of the popular hunter constellation.

The nebula itself is located on the lower half of the image, surrounded by a ring of dust. It formed in a cold cloud of gas and dust and contains about 1,000 young stars. These stars illuminate the cloud, creating the beautiful nebulosity, or swirls of material, seen here in infrared.

This image shows infrared light captured by Spitzer's infrared array camera. Light with wavelengths of 8 and 5.8 microns (red and orange) comes mainly from dust that has been heated by starlight. Light of 4.5 microns (green) shows hot gas and dust; and light of 3.6 microns (blue) is from starlight.

Take a look or download Orion's Portrait at medium or high resolution.

Credit: NASA-Spitzer Space Telescope

New Discoveries at Uranus

Friday, January 6, 2006

Fully-labeled composite image
Fully-labeled composite image

Credit: NASA, ESA, and M. Showalter (SETI Institute)

Deep exposure of Uranus taken with the Hubble Space Telescope reveal two small moons and two faint rings. All orbit outside of Uranus's previously known (main) ring system, but interior to the large, classical moons. The outer new moon, U XXVI Mab, orbits at roughly twice the radius of the main rings and shares its orbit with a dust ring. The second moon, U XXVII Cupid, orbits just interior to the satellite Belinda. A second ring falls between the orbits of Portia and Rosalind, in a region with no known source bodies. Collectively, these constitute a densely-packed, rapidly varying and possibly unstable dynamical system.

More: SETI - New Discoveries at Uranus

Hubble Prospects For Resources on The Moon

Saturday, November 12, 2005

Apollo 17 Landing Site
Apollo 17 Landing Site, HST and Apollo mission images. NASA/ESA/HST Moon Team
Although U.S. astronauts have visited the moon before, they only spent a few days there, making short forays into the barren landscape. A new Vison for Space Exploration, announced by President George W. Bush in January 2004, calls for the establishment of human outposts on the moon and later, human exploration of Mars. This time, we're going back to stay.

To prepare for potential manned missions to the Earth's Moon, NASA scientists are using the Hubble Space Telescope to hunt for resources, such as oxygen, that are essential for people to survive and to sustain their existence on the lunar surface. Hubble's preliminary observations and results are promising. A preliminary assessment of the Hubble observations pinpoints possible locations of ilmenite, a titanium oxide rich in oxygen, at the Apollo 17 landing region. Ilmenite is a potentially key resource because it contains easily extracted oxygen, which can be used for breathing and for rocket fuel. Since the moon doesn't have an atmosphere, scientists must hunt for oxygen in lunar soils if we are to learn to live off the “land”.

More: NASA - Hubble Prospects For Resources on The Moon

Hubble Spots Possible New Moons Around Pluto

Saturday, November 12, 2005

HST images showing two new candidate satellites orbiting around Pluto
HST images showing two new candidate satellites orbiting around Pluto
The Hubble Space Telescope images shown left, taken by the Advanced Camera for Surveys, reveal Pluto, its large moon Charon, and the planet's two new candidate satellites. Between May 15 and May 18, 2005, Charon, and the potential moons, provisionally designated P1 and P2, all appear to rotate counterclockwise around Pluto. P1 and P2 move less than Charon because they are farther from Pluto, and therefore would be orbiting at slower speeds. P1 and P2 are thousands of times less bright than Pluto and Charon. The enhanced-color images of Pluto (the brightest object) and Charon (to the right of Pluto) were constructed by combining short exposure images. The images of the new satellites were made from longer exposures.

More: NASA - Hubble Spots Possible New Moons Around Pluto - view more images and get the full story on this exciting discovery!

Hubble's Eye on Mars

Wednesday, August 27, 2003

NASA's Hubble Space Telescope snapshot of Mars
NASA's Hubble Space Telescope snapshot of Mars

NASA's Hubble Space Telescope took this snapshot of Mars 11 hours before the planet made its closest approach to Earth. The two planets are 34,648,840 miles (55,760,220 km) apart. This image was made from a series of exposures taken between 6:20 p.m. and 7:12 p.m. EDT Aug. 26 with Hubble's Wide Field and Planetary Camera 2.

Photo credit: NASA/J. Bell (Cornell U.) and M. Wolff (SSI)

330 x 330, 32 KB

NASA's Hubble Space Telescope made observations of the planet Mars on August 26 and 27, when Earth and Mars were closer together than they have been in the last 60,000 years. As Hubble's high-resolution images of the Red Planet are received at the Space Telescope Science Institute and are digitally processed by the Mars observing team, they will be released to the public and news media via the Internet. The Hubble images are the sharpest views of Mars ever taken from Earth. They reveal surface details as small as 17 miles (24 km) across. Though NASA's Mars-orbiting spacecraft can photograph the Red Planet in much finer detail, Hubble routinely serves as a "weather satellite" for tracking atmospheric changes on Mars and for probing its geology on a global scale.

More: NASA - Hubble Space Telescope's Viewing Plans For Earth's 'Close Encounter' With Mars

Link: Sky & Telescope - Mars at Its All-Time Finest

A Cold New World

Tuesday, October 8, 2002

NASA's Hubble Space Telescope measured the largest object in the solar system seen since the discovery of Pluto 72 years ago. The icy world 2002 LM60, dubbed "Quaoar" by its discoverers, measures 1300 kilometers wide - approximately half the size of Pluto. Just a curious point of light until recently, Quaoar lies a billion kilometers beyond Pluto.

More: Science@NASA - A Cold New World