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Results from Spitzer
Scientists present new discoveries from the Spitzer Space Telescope, including their findings of raw ingredients for life detected around young stars. (53min 03sec file)
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Spacewalk previewed
The Expedition 9 crew describes their upcoming spacewalk in Russian spacesuits, life aboard the space station and the view of Earth in this interview with Bill Harwood of CBS News. (20min 19sec file)
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Progress undocking
The Progress 13P cargo ship departs the International Space Station on May 24 carrying trash and unneeded items to burn up in the atmosphere. (2min 56sec file)
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AP interviews the crew
The Associated Press interviews the two-man Expedition 9 crew living aboard the International Space Station on May 24. (9min 36sec file)
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Atlas launches AMC-11
The Lockheed Martin Atlas 2AS rocket launches from Cape Canaveral carryin the AMC-11 communications satellite. (4min 30sec file)
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Moon tells of unexpected Earth climate changes
CALIFORNIA INSTITUTE OF TECHNOLOGY NEWS RELEASE
Posted: May 28, 2004

Scientists who monitor Earth's reflectance by measuring the moon's "earthshine" have observed unexpectedly large climate fluctuations during the past two decades.

By combining eight years of earthshine data with nearly twenty years of partially overlapping satellite cloud data, they have found a gradual decline in Earth's reflectance that became sharper in the last part of the 1990s, perhaps associated with the accelerated global warming in recent years.

Surprisingly, the declining reflectance reversed completely in the past three years. Such changes, which are not understood, seem to be a natural variability of Earth's clouds.

The May 28, 2004, issue of the journal Science examines the phenomenon in an article, "Changes in Earth's Reflectance Over the Past Two Decades," written by Enric Palle, Philip R. Goode, Pilar Montanes Rodriguez, and Steven E. Koonin. Goode is distinguished professor of physics at the New Jersey Institute of Technology (NJIT), Palle and Montanes Rodriguez are postdoctoral associates at that institution, and Koonin is professor of theoretical physics at the California Institute of Technology. The observations were conducted at the Big Bear Solar Observatory (BBSO) in California, which NJIT has operated since 1997 with Goode as its director. The National Aeronautics Space Administration funded these observations.

The team has revived and modernized an old method of determining Earth's reflectance, or albedo, by observing earthshine, sunlight reflected by the Earth that can be seen as a ghostly glow of the moon's "dark side"-or the portion of the lunar disk not lit by the sun. As Koonin realized some 14 years ago, such observations can be a powerful tool for long-term climate monitoring. "The cloudier the Earth, the brighter the earthshine, and changing cloud cover is an important element of changing climate," he said.

Precision earthshine observations to determine global reflectivity have been under way at BBSO since 1994, with regular observations commencing in late 1997.

"Using a phenomenon first explained by Leonardo DaVinci, we can precisely measure global climate change and find a surprising story of clouds. Our method has the advantage of being very precise because the bright lunar crescent serves as a standard against which to monitor earthshine, and light reflected by large portions of Earth can be observed simultaneously," said Goode. "It is also inexpensive, requiring only a small telescope and a relatively simple electronic detector."

By using a combination of earthshine observations and satellite data on cloud cover, the earthshine team has determined the following:

Earth's average albedo is not constant from one year to the next; it also changes over decadal timescales. The computer models currently used to study the climate system do not show such large decadal-scale variability of the albedo.

The annual average albedo declined very gradually from 1985 to 1995, and then declined sharply in 1995 and 1996. These observed declines are broadly consistent with previously known satellite measures of cloud amount.

The low albedo during 1997-2001 increased solar heating of the globe at a rate more than twice that expected from a doubling of atmospheric carbon dioxide. This "dimming" of Earth, as it would be seen from space, is perhaps connected with the recent accelerated increase in mean global surface temperatures.

2001-2003 saw a reversal of the albedo to pre-1995 values; this "brightening" of the Earth is most likely attributable to the effect of increased cloud cover and thickness.

These large variations, which are comparable to those in the earth's infrared (heat) radiation observed in the tropics by satellites, comprise a large influence on Earth's radiation budget.

"Our results are only part of the story, since the Earth's surface temperature is determined by a balance between sunlight that warms the planet and heat radiated back into space, which cools the planet," said Palle. "This depends upon many factors in addition to albedo, such as the amount of greenhouse gases (water vapor, carbon dioxide, methane) present in the atmosphere. But these new data emphasize that clouds must be properly accounted for and illustrate that we still lack the detailed understanding of our climate system necessary to model future changes with confidence."

Goode says the earthshine observations will continue for the next decade. "These will be important for monitoring ongoing changes in Earth's climate system. It will also be essential to correlate our results with satellite data as they become available, particularly for the most recent years, to form a consistent description of the changing albedo. Earthshine observations through an 11-year solar cycle will also be important to assessing hypothesized influences of solar activity on climate."

Montanes Rodriguez says that to carry out future observations, the team is working to establish a global network of observing stations. "These would allow continuous monitoring of the albedo during much of each lunar month and would also compensate for local weather conditions that sometimes prevent observations from a given site."

BBSO observations are currently being supplemented with others from the Crimea in the Ukraine, and there will soon be observations from Yunnan in China, as well. A further improvement will be to fully automate the current manual observations. A prototype robotic telescope is being constructed and the team is seeking funds to construct, calibrate, and deploy a network of eight around the globe.

"Even as the scientific community acknowledges the likelihood of human impacts on climate, it must better document and understand climate changes," said Koonin. "Our ongoing earthshine measurements will be an important part of that process."

Ferryflight Shuttle Patch

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"The Final Mission" - NASA emblem developed for the Shuttle Carrier Aircraft crew and their support teams to deliver the orbiters to their final destinations at museums.
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Soviet Space
For the first time ever available in the West. Rocket & Space Corporation Energia: a complete pictorial history of the Soviet/Russian Space Program from 1946 to the present day all in full color. Available from our store.
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Viking patch
This embroidered mission patch celebrates NASA's Viking Project which reached the Red Planet in 1976.
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Apollo 7 DVD
For 11 days the crew of Apollo 7 fought colds while they put the Apollo spacecraft through a workout, establishing confidence in the machine what would lead directly to the bold decision to send Apollo 8 to the moon just 2 months later.
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Gemini 12
Gemini 12: The NASA Mission Reports covers the voyage of James Lovell and Buzz Aldrin that capped the Gemini program's efforts to prove the technologies and techniques that would be needed for the Apollo Moon landings. Includes CD-ROM.
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Apollo 12 tribute DVD set

New! Featuring the jovial crew of Pete Conrad, Dick Gordon and Alan Bean, the Apollo 12 mission was struck by lightning shortly after liftoff but proceeded on the second successful exploration voyage to the lunar surface. This three-disc DVD brings the mission to life with extraordinary detail.
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Fallen Heroes special patch
This special 12-inch embroidered patch commemorates the U.S. astronauts who made the ultimate sacrifice, honoring the crews of Apollo 1, Challenger and Columbia.
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Women in Space
Women of Space: Cool Careers on the Final Frontier is for girls, young women, and anyone else interested in learning about exciting careers in space exploration. Includes CD-ROM.
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Mars rover poster
This new poster features some of the best pictures from NASA's amazing Mars Exploration Rovers Spirit and Opportunity.
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Gemini 12
Gemini 12: The NASA Mission Reports covers the voyage of James Lovell and Buzz Aldrin that capped the Gemini program's efforts to prove the technologies and techniques that would be needed for the Apollo Moon landings. Includes CD-ROM.
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John Glenn Mission Patch

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The historic first orbital flight by an American is marked by this commemorative patch for John Glenn and Friendship 7.
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Final Shuttle Mission Patch

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The crew emblem for the final space shuttle mission is available in our store. Get this piece of history!
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Celebrate the shuttle program

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This special commemorative patch marks the retirement of NASA's Space Shuttle Program. Available in our store!
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Anniversary Shuttle Patch

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This embroidered patch commemorates the 30th anniversary of the Space Shuttle Program. The design features the space shuttle Columbia's historic maiden flight of April 12, 1981.
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Mercury anniversary

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Celebrate the 50th anniversary of Alan Shephard's historic Mercury mission with this collectors' item, the official commemorative embroidered patch.
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Fallen Heroes Patch Collection
The official patches from Apollo 1, the shuttle Challenger and Columbia crews are available in the store.
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