Goddard Space Flight Center
Goddard Space Flight Center
News Article | May 12, 2017
Tropical Cyclone Ella is intensifying and NASA observed heavy rainfall in the storm. Ella is now expected to pass to the north of Fiji which is good news for the island nation. The Global Precipitation Measurement mission or GPM core observatory satellite flew over intensifying Tropical Cyclone Ella in the South Pacific on May 10, 2017 at 2301 UTC (7:01 p.m. EDT). The satellite's Microwave Imager (GMI) and Dual-Frequency Precipitation Radar (DPR) instruments showed bands of curved rainfall bands wrapping into the center of a well-defined center of circulation. GPM's DPR measured rain falling at a rate of over 231 mm (9.1 inches) per hour in an intense feeder band on Ella's eastern side. GPM is a joint mission between NASA and the Japanese space agency JAXA. At NASA's Goddard Space Flight Center in Greenbelt, Maryland, a 3-D view of Tropical Cyclone Ella was produced using GPM radar reflectivity data (DPR Ku Band). DPR showed that the highest storm tops around the intensifying tropical cyclone were located in intense storms in the feeder band on Ella's eastern side. Some of these powerful storms were found by GPM's DPR to reach altitudes above 15.5 km (9.6 miles). On May 11 at 1500 UTC (11 a.m. EDT), Ella's maximum sustained winds had increased to 70 knots (80 mph/129.6 kph).The center of Ella was located about 324 nautical miles northeast of Suva, Fiji near 13.7 degrees south latitude and 178.7 degrees west longitude. Ella was moving to the west at 4 knots (4.6 mph/7.4 kph). Fiji has a strong wind warning in effect for Vanua Levu, Taveuni and nearby smaller islands and Northern Lau Group. The Joint Typhoon Warning Center (JTWC) noted that animated enhanced infrared satellite imagery showed Ella was a compact system with a small central dense overcast. Ella has tightly curved thunderstorm banding wrapping into a small microwave eye feature along the northwest edge of the central convection. JWTC forecasts that Ella will move west and stay to the north of Fiji. The storm is at peak intensity and will gradually weaken, until it dissipates within about four days.
News Article | May 11, 2017
Tropical Cyclone Donna was one of the most powerful out-of-season tropical cyclones ever recorded in the southern hemisphere and generated extreme amounts of rainfall along its path. NASA analyzed and mapped rainfall totals generated by the storm. On May 10, 2017 rapidly dissipating tropical Cyclone Donna moved to the southeast of New Caledonia in the South Pacific. Up until that time, Donna spread heavy rainfall along its path from northern Vanuatu through the Loyalty Islands east of New Caledonia. Over 250 millimeters (~10 inches) of rainfall was reported in the islands of northern Vanuatu as Donna was moving through on May 5, 2017. At NASA's Goddard Space Flight Center in Greenbelt, Maryland, a rainfall analysis was constructed using data from NASA's Integrated Multi-satellitE Retrievals for GPM (IMERG). GPM is the Global Precipitation Measurement satellite, which is co-managed by NASA and the Japan Aerospace Exploration Agency. That data collected from the GPM core satellite in near-real time were utilized in IMERG's rainfall accumulation estimates for tropical cyclone Donna. The analysis covers tropical cyclone Donna for the period from May 2 through early May 10, 2017. IMERG showed that tropical cyclone Donna produced some extremely high rainfall totals. It indicated that the most extreme rainfall accumulation estimates were greater than 62.4 millimeters (24.6 inches). Those extreme values were located along Donna's path through the northern islands of Vanuatu. The tropical cyclone passed to the east of New Caledonia on the southern portion of its track so the Loyalty Islands east of New Caledonia received the heaviest rainfall in that area. By May 11, Donna had dissipated in the Southern Pacific Ocean. The Integrated Multi-satellitE Retrievals for GPM (IMERG) is a unified U.S. algorithm that provides a multi-satellite precipitation product. IMERG is run twice in near-real time with the "early" multi-satellite product being created at about 4 hours after observation time and a "late" multi-satellite product is provided at about 12 hours after observation time. IMERG rainfall totals have been adjusted to reflect observed values in other similar extreme rainfall events. For more information about GPM, visit: http://www. .
News Article | May 10, 2017
KBRwyle will provide engineering services throughout the spacecraft mission life cycle for mission operations, including concept studies, design, development, integration, test, verification, operations, sustainment of mission operations systems and subsystems, and operations processes and procedures. "We are very pleased to have been awarded this contract by NASA to support the agency's missions managed by Goddard Space Flight Center," said Stuart Bradie, KBR President & CEO. "KBRwyle and its heritage organizations have partnered with NASA in advancing technology and science at Goddard as well as other NASA operations across the country for more than half a century. We are looking forward to the opportunity to continue to contribute KBRwyle's expertise to NASA," Bradie continued. As task orders are awarded throughout the contract period on this single award IDIQ contract, they will be booked into backlog of unfilled orders for KBR's Government Services business segment. KBR is a global provider of differentiated professional services and technologies across the asset and program life cycle within the Government Services and Hydrocarbons sectors. KBR employs over 34,000 people worldwide (including our joint ventures), with customers in more than 80 countries, and operations in 40 countries, across three synergistic global businesses: KBR is proud to work with its customers across the globe to provide technology, value-added services, integrated EPC delivery and long term operations and maintenance services to ensure consistent delivery with predictable results. At KBR, We Deliver. The statements in this press release that are not historical statements, including statements regarding future financial performance, are forward-looking statements within the meaning of the federal securities laws. These statements are subject to numerous risks and uncertainties, many of which are beyond the company's control that could cause actual results to differ materially from the results expressed or implied by the statements. These risks and uncertainties include, but are not limited to: the outcome of and the publicity surrounding audits and investigations by domestic and foreign government agencies and legislative bodies; potential adverse proceedings by such agencies and potential adverse results and consequences from such proceedings; the scope and enforceability of the company's indemnities from its former parent; changes in capital spending by the company's customers; the company's ability to obtain contracts from existing and new customers and perform under those contracts; structural changes in the industries in which the company operates; escalating costs associated with and the performance of fixed-fee projects and the company's ability to control its cost under its contracts; claims negotiations and contract disputes with the company's customers; changes in the demand for or price of oil and/or natural gas; protection of intellectual property rights; compliance with environmental laws; changes in government regulations and regulatory requirements; compliance with laws related to income taxes; unsettled political conditions, war and the effects of terrorism; foreign operations and foreign exchange rates and controls; the development and installation of financial systems; increased competition for employees; the ability to successfully complete and integrate acquisitions; and operations of joint ventures, including joint ventures that are not controlled by the company. KBR's most recently filed Annual Report on Form 10-K, any subsequent Form 10-Qs and 8-Ks, and other Securities and Exchange Commission filings discuss some of the important risk factors that KBR has identified that may affect the business, results of operations and financial condition. Except as required by law, KBR undertakes no obligation to revise or update publicly any forward-looking statements for any reason. To view the original version on PR Newswire, visit:http://www.prnewswire.com/news-releases/kbr-awarded-engineering-services-contract-to-support-nasa-exploration-missions-300454850.html
News Article | May 8, 2017
NASA's James Webb Space Telescope has arrived at NASA’s Johnson Space Center in Houston, Texas, where it will undergo its last cryogenic test before it is launched into space in 2018. The telescope was loaded onto a trailer truck from NASA’s Goddard Space Flight Center in Greenbelt, Md., and moved slowly down a highway by the Webb team to U.S. Air Force’s Joint Base Andrews in Maryland. At Andrews, the telescope was then loaded onto a C-5 aircraft and flown to Ellington Field in Houston, Texas. When the C-5 landed at Ellington, the telescope was carefully unloaded and delivered to NASA Johnson. In the coming weeks, the telescope will be prepared for a final cryogenic test that will run approximately 100 days. Then, it will continue its journey to Northrop Grumman Aerospace Systems in Redondo Beach, California, for final integration and testing with the remainder of the Webb Observatory — the sunshield and spacecraft bus — prior to launch. To ensure the telescope's optics will operate at its frigid destination 1 million miles out in space, it must complete several cryogenic tests. The last cryogenic test will occur in Johnson's Chamber A, the same vacuum chamber where the Apollo spacecraft were tested. This critical end-to-end optical test will test the telescope at its extremely cold operating temperatures — at 40 Kelvin — the temperature that it will operate in space. The James Webb Space Telescope is the world’s most advanced space observatory. This engineering marvel is designed to unravel some of the greatest mysteries of the universe, from discovering the first stars and galaxies that formed after the big bang to studying the atmospheres of planets around other stars. It is a joint project of NASA, ESA (the European Space Agency), and the Canadian Space Agency, and was assembled in a Class 10,000 cleanroom at NASA's Goddard Space Flight Center.
News Article | May 11, 2017
A new study led by NASA with contributions from the University of Maryland reveals that the distant planet HAT-P-26b has a primitive atmosphere composed almost entirely of hydrogen and helium. Located about 437 light years away from Earth, HAT-P-26b orbits a star roughly twice as old as the sun. The analysis is one of the most detailed studies to date of a "warm Neptune," a planet that is Neptune-sized and orbits close to its star. By combining observations from NASA's Hubble and Spitzer space telescopes, the researchers determined that HAT-P-26b's atmosphere is relatively clear of clouds and has a strong water signature, although the planet is not a water world. The study, published in the May 12, 2017 issue of the journal Science, also provides the best measurement to date of water on an exoplanet of this size. "Not too long ago, it was exciting just to find an exoplanet," said Drake Deming, a professor of astronomy at UMD and a co-author of the study. "But now, as technology and methods become more refined, we are building a whole new understanding of the wide diversity of planetary systems beyond our own. It's a very exciting time to be in this field." The discovery of such a primordial atmosphere on this Neptune-sized planet has implications for how scientists think about the birth and development of planetary systems. Compared to Neptune and Uranus, the planets in our solar system with about the same mass, HAT-P-26b likely formed either closer to its host star or later in the development of its planetary system--or a combination of both. "Astronomers have just begun to investigate the atmospheres of these distant Neptune-mass planets, and almost right away, we found an example that goes against the trend in our solar system," said Hannah Wakeford, a postdoctoral researcher at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study. "This kind of unexpected result is why I really love exploring the atmospheres of alien planets." To study HAT-P-26b's atmosphere, the researchers used data from transits-- occasions when the planet passed in front of its host star. During a transit, a fraction of the starlight gets filtered through the planet's atmosphere, which absorbs some wavelengths of light but not others. By looking at how the signatures of the starlight change as a result of this filtering, researchers can work backward to figure out the chemical composition of the atmosphere. In this case, the team pooled data from four transits measured by Hubble and two seen by Spitzer. Together, these observations covered a wide range of wavelengths from yellow light through the near-infrared region. "To have so much information about a warm Neptune is still rare, so analyzing these data sets simultaneously is an achievement in and of itself," said co-author Tiffany Kataria of the Jet Propulsion Laboratory in Pasadena, California. Because the study provided a precise measurement of water, the researchers were able to use the water signature to estimate HAT-P-26b's metallicity--an indication of how rich the planet is in all elements heavier than hydrogen and helium. Astronomers calculate metallicity to provide clues about how a planet formed. To compare planets by their metallicities, scientists use the sun as a point of reference--almost like describing how much caffeine a beverage has by comparing it to a cup of coffee. Jupiter has a metallicity about 2 to 5 times that of the sun. For Saturn, it's about 10 times as much as the sun. These relatively low values mean that the two gas giants are made almost entirely of hydrogen and helium. The ice giants Neptune and Uranus are smaller than the gas giants but richer in the heavier elements, with metallicities of about 100 times that of the sun. So, for the four outer planets in our solar system, the trend is that the metallicities are lower for the bigger planets. Scientists think this happened because, as the solar system was taking shape, Neptune and Uranus formed in a region toward the outskirts of the enormous disk of dust, gas and debris that swirled around the immature sun. Summing up the complicated process of planetary formation in a nutshell: Neptune and Uranus would have been bombarded with a lot of icy debris that was rich in heavier elements. Jupiter and Saturn, which formed in a warmer part of the disk, would have encountered less of the icy debris. Two planets beyond our solar system also fit this trend. One is the Neptune-mass planet HAT-P-11b. The other is WASP-43b, a gas giant twice as massive as Jupiter. But Wakeford and her colleagues found that HAT-P-26b bucks the trend. They determined its metallicity is only about 4.8 times that of the sun, much closer to the value for Jupiter than for Neptune. "This analysis shows that there is a lot more diversity in the atmospheres of these exoplanets than we were expecting, which is providing insight into how planets can form and evolve differently than in our solar system," said David K. Sing of the University of Exeter and the second author of the paper. "I would say that has been a theme in the studies of exoplanets: Researchers keep finding surprising diversity." The research paper, "HAT-P-26b: A Neptune-mass Exoplanet with a Well-constrained Heavy Element Abundance," Hannah Wakeford, David Sing, Tiffany Kataria, Drake Deming, Nikolay Nikolov, Eric Lopez, Pascal Tremblin, David Amundsen, Nikole Lewis, Avi Mandell, Jonathan Fortney, Heather Knutson, Björn Benneke and Tom Evans, was published May 12, 2017 in the journal Science. This work was supported by the European Space Agency, NASA (Award Nos. NAS 5-26555 and HST-GO-14260) and the European Research Council (Award Nos. 336792, 313014, and 247060-PEPS). The content of this article does not necessarily reflect the views of these organizations. This release is adapted from text provided by NASA's Goddard Space Flight Center. University of Maryland College of Computer, Mathematical, and Natural Sciences 2300 Symons Hall College Park, MD 20742 http://www. @UMDscience About the College of Computer, Mathematical, and Natural Sciences The College of Computer, Mathematical, and Natural Sciences at the University of Maryland educates more than 7,000 future scientific leaders in its undergraduate and graduate programs each year. The college's 10 departments and more than a dozen interdisciplinary research centers foster scientific discovery with annual sponsored research funding exceeding $150 million.
News Article | May 13, 2017
An exoplanet located about 437 light-years away with a mass comparable to that of Neptune or Uranus sheds light on how planets form around their host stars. HAT-P-26b, also called "warm Neptune," is characterized by an atmosphere composed mostly of hydrogen and helium. Data from the Hubble and Spitzer space telescopes helped astronomers determine the planet's metallicity, a measure of elements that are heavier than helium and hydrogen in the atmosphere that can help determine how a planet formed. If a planet has more heavier elements compared with the sun, it is described to have high metallicity. Jupiter has a metallicity of about two to five times that of the solar system's sun, while Saturn has a metallicity of about 10 times that of the sun. The low values suggest that these two gas giants are almost made up of hydrogen and helium. Neptune and Uranus, the ice giants of the solar system, are smaller compared with the gas giants but have heavier elements with 100 times the metallicity of the sun. In the solar system, the trend is that bigger planets like Jupiter and Saturn tend to have lower metallicities. Astronomers said that this likely happened because during the formation of the solar system, Neptune and Uranus formed in the outskirts of the disk that circled around the sun and these planets were likely pounded by icy debris carrying heavier elements. The metallicity of Saturn and Jupiter indicates that they likely formed closer to the sun, where there was fewer icy debris present. The gas giants formed in the warmer region of the disk, which means they were less hit by those objects. Researchers found that HAT-P-26b has 4.8 times the amount of heavy elements found in the sun, which means it has relatively low metallicity when compared with the standards of the solar system. Based on the assumed metallicity of the exoplanet, researchers also argued that HAT-P-26b formed closer to its star than it is now. Despite having a mass comparable with Neptune and Uranus, its metallicity is closer in value to Jupiter's than the two icy planets. "We were expecting [HAT-P-26b] to have a very high metallicity, but what we found is it's actually closer to Jupiter in the amount of heavy elements it has in its atmosphere," said study researcher Hannah Wakeford, of NASA's Goddard Space Flight Center in Greenbelt, Maryland. The researchers said that their analysis shows more diversity in the atmosphere of exoplanets than expected. It also offers insights on how exoplanets can form and evolve differently from the solar system. Scientists said they often find diversity when studying extraterrestrial worlds. "I would say that has been a theme in the studies of exoplanets: Researchers keep finding surprising diversity," said study researcher David Sing from the University of Exeter. Results of the analysis of warm Neptune were reported in a study published in Science on May 12. © 2017 Tech Times, All rights reserved. Do not reproduce without permission.
News Article | May 10, 2017
Telescopes literally from around the world have banded together to give us a detailed look at the Crab Nebula, the remnant of a supernova explosion that has been hanging in our night sky for 1,000 years. Scientists used data from three Earth-orbiting satellites, another that trails the Earth in its orbit around the sun, and a telescope on the ground in New Mexico to piece together a view of the nebula, complete with the quickly rotating neutron star at its center, the remnant of the star that exploded to produce it. NASA’s Goddard Space Flight Center said the telescope images represent almost the whole electromagnetic spectrum: radio waves from the Karl G. Jansky Very Large Array on Earth, infrared from the Spitzer Space Telescope as it trails Earth in orbit around the sun, and from satellite orbit, Hubble Space Telescope’s visible light, the XMM-Newton Observatory’s ultraviolet and Chandra X-ray Observatory’s X-rays. In a video (below), NASA combines them, using a different color for each — red, yellow, green, blue and purple, respectively. Read: How a Supernova Kills You in Space The images were taken a few years ago, but astronomers have been analyzing them to learn more about how supernova remnants work. Viewing it through different wavelengths gives scientists multiple perspectives from which to study it. Supernova explosions occur when a star accumulates too much mass, whether that’s because it’s very old or because it has devoured a companion star, in the case of binary star systems where more than one star orbits the same point in space together. Astrophysicist Neil deGrasse Tyson has described it as “one of the greatest events in the universe.” It’s the biggest space explosion there is. “It would look beautiful up close, right up until the energy intensity vaporized you,” Tyson has said. In the case of the Crab Nebula, which is 6,500 light years away, the remnant of the exploded star spins at its center, rotating about 30 times a second. That neutron star is a pulsar that is “shooting out rotating lighthouse-like beams of radio waves and light,” NASA said. “The nebula’s intricate shape is caused by a complex interplay of the pulsar, a fast-moving wind of particles coming from the pulsar, and material originally ejected by the supernova explosion and by the star itself before the explosion.” Earth observers today can only see what the supernova explosion has left behind, but Chinese astronomers and other stargazers witnessed the supernova blowing up in 1054, with the Chinese first noting it on July 4 of that year. “Knowledge of star-fields was not necessary to spot this surprising visitor,” Space.com explained. “According to records, the bright source was visible during the daytime for 23 days, shining six times as brightly as Venus. Those well-versed with the night sky would have been able to see it for 653 days — almost two years — with the naked eye.” Japanese, Arabic and Native American astronomers also took note of the event, and since its discovery hundreds of years ago, it has been a star target of space enthusiasts. Imagine Our Universe with this Stunning NASA Art
News Article | May 11, 2017
On April 12, one of the spacecraft's instruments – the Large Area Telescope (LAT), which was conceived of and assembled at the Department of Energy's SLAC National Accelerator Laboratory – detected its billionth extraterrestrial gamma ray. Since gamma rays are often produced in violent processes, their observation sheds light on extreme cosmic environments, such as powerful star explosions, high-speed particle jets spewed out by supermassive black holes, and ultradense neutron stars spinning unimaginably fast. Gamma rays could also be telltale signs of dark matter particles – hypothetical components of invisible dark matter, which accounts for 85 percent of all matter in the universe. "Since Fermi's launch in 2008, the LAT has made a number of important discoveries of gamma-ray emissions from exotic sources in our galaxy and beyond," says Robert Cameron, head of the LAT Instrument Science Operations Center (ISOC) at SLAC. The LAT has already collected hundreds of times more gamma rays than the previous-generation EGRET instrument on NASA's Compton Gamma-ray Observatory – an advance that has tremendously deepened insights into the production of this energetic radiation. Among the LAT discoveries are more than 200 pulsars – rapidly rotating, highly magnetized cores of collapsed stars that were up to 30 times more massive than the sun. Before Fermi's launch, only seven of these objects were known to emit gamma rays. As pulsars spin around their axis, they emit "beams" of gamma rays like cosmic lighthouses. Many pulsars rotate several hundred times per second – that's tens of millions times faster than Earth's rotation. "Understanding pulsars tells us about the evolution of stars because they are one possible end point in a star's life," Cameron says. "The LAT data have led us to totally revise our understanding of how pulsars emit gamma rays." The LAT has also shown for the first time that novae – thermonuclear explosions on the surface of stars that have accumulated material from neighboring stars – can emit gamma rays. These data provide new details about the physics of burning stars, which is a crucial process for the synthesis of chemical elements in the universe. Even more exotic gamma-ray sources detected by the LAT are microquasars. These objects are star-sized analogs of active galactic nuclei, with gas spinning around a black hole at the center. As the black hole devours matter from its surroundings, it ejects jets of charged particles traveling almost as fast as light into space, generating beams of gamma rays in the process. At a galactic scale, such an ejection mechanism could have produced what is known as the Fermi bubbles – two giant areas above and below the center of the disk of our Milky Way galaxy that shine in gamma rays. Discovered by the LAT in 2010, these bubbles suggest that the supermassive black hole at the center of our galaxy once was more active than it is today. Researchers also use the LAT to search for signs of dark matter particles in the central regions of the Milky Way and other galaxies. Theories predict that the hypothetical particles would produce gamma rays when they decay or collide and destroy each other. "With the sensitivity we have achieved with the LAT, we should in principle be able to see such dark matter signatures," says SLAC's Seth Digel, who leads the Fermi group at the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), a joint institute of Stanford University and SLAC. "But we haven't found any conclusive signals yet, and so far the LAT data can also be explained with other astrophysical sources." Finally, the LAT has explored gamma ray sources closer to home, including gamma rays produced by thunderstorms in Earth's atmosphere, by solar flares and even by charged particles hitting the surface of the moon. From its location on Fermi at an altitude of 330 miles, the LAT sees 20 percent of the sky at any given time. Every two orbits – each takes about 95 minutes – the instrument collects the data necessary for a gamma-ray map of the entire sky. But identifying the right signals for the map is a little bit like finding needles in a haystack: For every gamma-ray photon, the LAT sees many more high-energy charged particles, called cosmic rays. Most of these background signals are rejected right away by hardware triggers and software filters in the LAT on Fermi, which reduces the rate of signals from 10,000 to 400 per second. The remaining data are compressed, transmitted back to Earth and sent to NASA's Goddard Space Flight Center in Greenbelt, Maryland, where they get separated into three different datasets for the LAT, the GBM (Fermi's second scientific instrument, which monitors short-lived gamma-ray bursts) and spacecraft data. The LAT data are transferred to the LAT ISOC at SLAC, where 1,000 computer cores automatically analyze the data stream and filter out even more background signals. 70 percent of all detected gamma rays are from Earth's atmosphere, leaving only two to three extraterrestrial gamma-ray signals per second out of the 10,000 initial detector events. These data are then sent back to NASA Goddard, where they are made publicly available for further analysis. "The ISOC receives about 15 deliveries of LAT data throughout the day for a total of 16 gigabytes or three DVDs worth of data every day," Cameron says. "For each delivery, the entire process – from the time the data leave Fermi to the time the gamma rays get deposited in the public archive – takes about four hours." Next year, the Fermi mission will reach its 10-year operations goal. What happens after that will largely depend on funding. "With no successor mission planned, the LAT is in many ways irreplaceable, particularly for studies of low-energy gamma rays," Digel says. "The telescope is still going strong after all these years, and there is a lot of science left to be done." An important new role for the LAT is to search for gamma-ray sources associated with gravitational wave events. These ripples in space-time occur, for example, when two black holes merge into a single one, as recently observed by the LIGO detector. This opens up the completely new field of gravitational wave astrophysics. The LAT ISOC is a department in KIPAC and the Particle Astrophysics and Cosmology Division of SLAC. KIPAC researchers contribute to the international Fermi LAT Collaboration, whose research is funded by NASA and the DOE Office of Science, as well as agencies and institutes in France, Italy, Japan and Sweden. Explore further: Origin of Milky Way's hypothetical dark matter signal may not be so dark
Seager S.,Massachusetts Institute of Technology |
Deming D.,Goddard Space Flight Center
Annual Review of Astronomy and Astrophysics | Year: 2010
At the dawn of the first discovery of exoplanets orbiting Sun-like stars in the mid-1990s, few believed that observations of exoplanet atmospheres would ever be possible. After the 2002 Hubble Space Telescope detection of a transiting exoplanet atmosphere, many skeptics discounted it as a one-object, one-method success. Nevertheless, the field is now firmly established, with over two dozen exoplanet atmospheres observed today. Hot Jupiters are the type of exoplanet currently most amenable to study. Highlights include: detection of molecular spectral features, observation of day-night temperature gradients, and constraints on vertical atmospheric structure. Atmospheres of giant planets far from their host stars are also being studied with direct imaging. The ultimate exoplanet goal is to answer the enigmatic and ancient question, "Are we alone?" via detection of atmospheric biosignatures.Two exciting prospects are the immediate focus on transiting super Earths orbiting in the habitable zone of M-dwarfs, and ultimately the spaceborne direct imaging of true Earth analogs. © 2010 by Annual Reviews.