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.
APEX takes a glimpse into the heart of darkness
25.05.2018 | Max-Planck-Institut für Radioastronomie
First chip-scale broadband optical system that can sense molecules in the mid-IR
24.05.2018 | Columbia University School of Engineering and Applied Science
The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.
Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...
A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.
The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...
At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.
At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...
There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?
At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...
So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics
Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...
25.05.2018 | Event News
02.05.2018 | Event News
13.04.2018 | Event News
25.05.2018 | Event News
25.05.2018 | Machine Engineering
25.05.2018 | Life Sciences