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STS-68: Radar mapper

A spectacular sight during STS-68 was the eruption of the Kliuchevskoi volcano on the Kamchatka Peninsula. The crew narrates post-flight movie.


The brightest supernova

Scientists tell the story about a monstrous explosion, a hundred times more energetic than a typical supernova. Observations have been made by the Chandra spacecraft and ground telescopes.


STS-64: Free-flying EVA

Spacewalking astronauts flying untethered from shuttle Discovery as they tested a new safety jetpack was a visual highlight of STS-64.


Astronaut Hall of Fame

Veteran space shuttle fliers Mike Coats, Steve Hawley and Jeff Hoffman are inducted into the Astronaut Hall of Fame at Kennedy Space Center during this ceremony held May 5.

 Part 1 | Part 2

Traveling on Freedom 7

Fly with Alan Shepard during his historic journey into space with this documentary that takes the viewer along as an invisible companion to America's first astronaut.


Encounter with Jupiter

The Pluto-bound New Horizons spacecraft recently flew past the Jovian system for a gravity sling-shot toward the outer solar system. New images of Jupiter and its moons are revealed in this briefing.

 Presentation | Q&A

"The Time of Apollo"

This stirring 1970s documentary narrated by Burgess Meredith pays tribute to the grand accomplishments of Apollo as men left Earth to explore the Moon and fulfill President Kennedy's challenge to the nation.


1958: America in space

This is a video report on the United States' space exploration efforts during 1958. These historic pioneering days included the launch of Explorer 1, the first American satellite to orbit Earth.


The Flight of Faith 7

The final and longest manned flight of Project Mercury was carried out by astronaut Gordon Cooper in May 1963. This film shows the voyage of Faith 7.


STS-62 crew report

Shuttle mission STS-62 was a two-week flight of Columbia with packages of microgravity research experiments housed on pallets in the payload bay. The crew narrates the highlights in this film.


Pegasus launches AIM

An air-launched Pegasus rocket lofts NASA's AIM satellite into orbit to study mysterious clouds at the edge of space.

 Full coverage

The Sun in 3-D

NASA's twin STEREO spacecraft have made the first three-dimensional images of the Sun. Scientists unveil the images in this news conference held April 23.


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Astronomers make the first map of an extrasolar planet
Posted: May 9, 2007

CAMBRIDGE, MA - For the first time, astronomers have created a rough map of a planet orbiting a distant sun-like star, employing a technique that may one day enable mapping of Earth-like worlds. Since the planet just charted is a gas giant and lacks a solid surface, the map shows cloud-top features. Using the Spitzer infrared space telescope, astronomers detected a bright hot spot that is offset from "high noon," where heating is greatest.

An artist's conception of HD 189733b, which some have dubbed the "Bulls-eye" planet because of the bright "hot spot" shown here. Credit: David A. Aguilar (CfA)
"We are getting our first good look at a completely alien world," said Heather Knutson, a graduate student at Harvard University and lead author of a paper about the research appearing in the May 10 issue of the journal Nature.

"We felt a little like Galileo must have felt when he first glimpsed Jupiter through the eyepiece of his telescope," Knutson continued.

Spitzer is only capable of mapping large, hot worlds - planets too hot for liquid water or life. However, the upcoming James Webb Space Telescope (scheduled for launch in 2013) may be able to map Earth-like worlds using the technique Knutson and her colleagues pioneered.

The team examined the planet, known as HD 189733b, using the Infrared Array Camera on board NASA's Spitzer Space Telescope. Infrared observations offer an advantage because the brightness difference between star and planet is lessened, making it easier to tease out the planet's signal.

Over the course of 33 hours, the team collected more than a quarter million data points. Although Spitzer could not resolve the planet into a disk, by measuring changes as the planet rotated, the team created a simple longitudinal map. That is, they measured the planet's brightness in a series of pole-to-pole strips across the planet's visible cloud-tops, then assembled those strips into an overall picture.

"We can see the changes in brightness as features in the planet's atmosphere rotate into and out of view," Knutson explained.

Four views of the planet's cloudtops in infrared light, each centered at a point of longitude 90 degrees from the last. A grid of longitude lines is superimposed on the map. These views clearly show a hot spot that is offset from the substellar point (high noon) by about 30 degrees. The offset may indicate fast "jet stream" winds of up to 6,000 mph. Credit: NASA/JPL-Caltech/Heather Knutson (CfA)
The map revealed a single "hot spot" that is about twice as big as the Great Red Spot on Jupiter and much hotter. The Great Red Spot is only about 30 degrees Fahrenheit warmer than its surroundings, with a temperature of -200 degrees F. In comparison, the hot spot on HD 189733b is a scorching 1700 degrees F.

Interestingly, researchers found that the hottest point on the planet is not the substellar point ("high noon" on the planet), but rather is offset by about 30 degrees longitudinally. They speculate that the shift is due to winds redistributing heat across the face of the planet.

"This planet has powerful jet streams. While Earth's jet stream blows at around 200 miles per hour, the jet stream on HD 189733b may blow as fast as 6,000 miles per hour, according to computer models," said co-author David Charbonneau (Harvard-Smithsonian Center for Astrophysics).

The distant planet's strong, hot winds may also help to keep the planet's night side warm. Without winds, the side facing the star would broil while the opposite side would freeze. However, the astronomers measured a maximum temperature difference of about 500 degrees F. The coldest regions on the night side remain a balmy 1200 degrees F.

"Every night is hot on this world," stated Knutson.

HD 189733b orbits a star slightly cooler and less massive than the Sun located about 60 light-years from Earth in the direction of the constellation Vulpecula. It is the closest known "transiting" planet to Earth.

HD 189733b orbits its star at a distance of only three million miles, completing one revolution every 2.2 days. Its mass and physical size are both slightly larger than Jupiter.

This discovery was made with Spitzer's Infrared Array Camera, built primarily at NASA Goddard Space Flight Center in Greenbelt, Maryland. The instrument's principal investigator is Giovanni Fazio of the Harvard-Smithsonian Center for Astrophysics.

NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer Space Telescope mission for NASA's Science Mission Directorate, Washington. Science operations are conducted at the Spitzer Science Center, Pasadena, Calif. JPL is a division of California Institute for Technology, Pasadena.