The finding, made using NASA's Spitzer Space Telescope, represents the first time that any kind of variation has been seen across the surface of a planet outside our solar system. Previous studies of such planets—known to astronomers as “extrasolar” planets—have described whole-globe traits such as size and mass.
The results appear online today in Science Express, and will also be presented at the 38th meeting of the Division for Planetary Sciences of the American Astronomical Society in Pasadena, California.
“This observation completely changes our thinking about hot gas giant exoplanets,” Seager said. “Most astronomers expected them to be more uniformly heated, much like Jupiter. But this planet clearly has a hot side and a cool side.”
The gas giant planet, named Upsilon Andromeda b, is a so-called "hot-Jupiter" that circles closely around its scorching star every 4.6 days. Seager and her colleagues determined that the temperature variation between the planet’s light side and its dark side is about 2,550 degrees Fahrenheit.
"This planet has a giant hot spot in the hemisphere that faces the star," said lead author Joe Harrington of the University of Central Florida, Orlando. "The temperature difference between the day and night sides tells about how energy flows in the planet's atmosphere. Essentially, we're studying weather on an exotic planet."
The team believes that the planet is "tidally locked" to its star, meaning that the planet rotates slowly enough that the same side always faces its star—much like our tidally locked moon never reveals its "dark side" to the Earth. However, since the planet is made of gas, not rock, its outer atmosphere could move faster than its locked interior.
The extreme temperature difference between the two sides could mean that the atmosphere of Upsilon Andromeda b absorbs and re-radiates sunlight rapidly, allowing the circling gases to quickly cool off as they move from light side to dark side. Jupiter, on the other hand, maintains an even temperature all around.
"If you were moving across the planet from the night side to day side, the temperature jump would be equivalent to leaping into a volcano," said the project's principal investigator, Brad Hansen of the University of California, Los Angeles.
The team used Spitzer’s heat-seeking infrared eyes to periodically stare at the Upsilon Andromeda planetary system over a period of about five days. They found that the system's light dimmed and brightened in time with Upsilon Andromeda b's orbit; this change in observed light, or heat, is the result of the planet showing its different faces as it travels around the star. When the planet's sunlit side was in Earth's view, Spitzer detected more light from the system; when its dark side was facing us, Spitzer picked up less light. The technique takes advantage of the fact that planets stand out better relative to their stars when viewed in infrared light.
"This is a spectacular result," said Michael Werner, project scientist for Spitzer at NASA's Jet Propulsion Laboratory, Pasadena, Calif. "When we designed Spitzer years ago, we did not anticipate that it would be revolutionizing extrasolar-planet science."
Upsilon Andromeda b was discovered in 1996 around the star Upsilon Andromeda, which is 40 light-years away and visible to the naked eye at night in the constellation Andromeda. The star is circled by two other known planets, both located farther out than Upsilon Andromeda b. The plane of this planetary system is tilted relative to our solar system, such that the planets are always in Earth's line of sight.
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Researchers create artificial materials atom-by-atom
28.03.2017 | Aalto University
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
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