NASA Space Telescope Finds Fewer Asteroids Near Earth

NASA Space Telescope Finds Fewer Asteroids Near Earth

New observations by NASA’s Wide-field Infrared Survey Explorer, or WISE, show there are significantly fewer near-Earth asteroids in the mid-size range than previously thought. The findings also indicate NASA has found more than 90 percent of the largest near-Earth asteroids, meeting a goal agreed to with Congress in 1998.

Astronomers now estimate there are roughly 19,500 — not 35,000 — mid-size near-Earth asteroids. Scientists say this improved understanding of the population may indicate that the hazard to Earth could be somewhat less than previously thought. However, the majority of these mid-size asteroids remain to be discovered. More research also is needed to determine if fewer mid-size objects (between 330 and 3,300 feet wide) also mean fewer potentially hazardous asteroids (those that come closest to Earth).

[SOURCE: www.cfa.harward.edu]

East of Huygens

East of Huygens

Saturn’s rings lie in the distance as the Cassini spacecraft looks toward Titan and its dark region called Shangri-La, east of the landing site of the Huygens Probe. See Hugyens’ Landing Site and Dawn at the Huygens Site to learn more. The moon’s north polar hood is also visible here. See Titan’s Hazes and Haze Layers on Titan to learn more about Titan’s atmosphere. This view looks toward the anti-Saturn side of Titan (5,150 kilometers, or 3,200 miles across). North on Titan is up. This view looks toward the northern, sunlit side of the rings from just above the ringplane. The image was taken with the Cassini spacecraft narrow-angle camera on Aug. 9, 2011 using a spectral filter sensitive to wavelengths of near-infrared light centered at 938 nanometers. The view was acquired at a distance of approximately 1.4 million kilometers (870,000 miles) from Titan and at a Sun-Titan-spacecraft, or phase, angle of 35 degrees. Image scale is 8 kilometers (5 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Space Calendar September 28 – October 4 2011

Space related activities and anniversaries for September 28 – October 4 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

Rhea Lit at Night

Rhea Lit at Night

Southern terrain on Saturn’s moon Rhea is dimly illuminated by Saturnshine in this Cassini spacecraft view of the dark side of the moon. The spacecraft’s camera is looking toward the night side of Rhea (1,528 kilometers, or 949 miles across), but sunlight reflected off the day side of immense Saturn is bright enough to illuminate the craters seen here. This view is centered on terrain at 23 degrees south latitude, 315 degrees west longitude. Four background stars are visible. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Aug. 1, 2011. The view was obtained at a distance of approximately 6,000 kilometers (3,700 miles) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 113 degrees. Scale in the original image was 800 meters (2,600 feet) per pixel. The image was contrast enhanced and magnified by a factor of 1.5 to enhance the visibility of surface features. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA’s Science Mission Directorate in Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging team is based at the Space Science Institute, Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov or http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org . Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Space Calendar September 21 – September 27 2011

Space related activities and anniversaries for September 21 – September 27 2011. Fetched live every week from NASA JPL

If you want the complete list going more than a year ahead then see the Space Calendar at NASA JPL.

Enceladus (Raw Image 1)

Enceladus (Raw Image 1)

This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2012. For more information on raw images check out our Frequently Asked Questions section. Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Enceladus (Raw Image 2)

Enceladus (Raw Image 2)

This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2012. For more information on raw images check out our Frequently Asked Questions section. Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Enceladus (Raw Image 3)

Enceladus (Raw Image 3)

This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2012. For more information on raw images check out our Frequently Asked Questions section. Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Enceladus (Raw Image 4)

Enceladus (Raw Image 4)

This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2012. For more information on raw images check out our Frequently Asked Questions section. Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]

Enceladus (Raw Image 5)

Enceladus (Raw Image 5)

This image has not been validated or calibrated. A validated/calibrated image will be archived with the NASA Planetary Data System in 2012. For more information on raw images check out our Frequently Asked Questions section. Credit: NASA/JPL-Caltech/Space Science Institute

[SOURCE: saturn.jpl.nasa.gov]