Observational Astronomy

Coronal heating and acceleration and NASA's Solar Probe Plus mission

The thermodynamic temperature of the Sun's atmosphere rises from ~6000K at the visible surface to millions of degrees in its outer atmosphere, the corona. This hot coronal plasma then expands supersonically to become the solar wind; this wind acceleration process is ongoing to very high altitudes (~10 solar radii) There is no sufficient thermal energy source for this heating and expansion, however remote sensing measurements of the coronal magnetic field suggest that the magnetic energy density is more than enough.

Space Buckyballs

Fullerenes are a class of large and remarkably stable carbonaceous molecules in the shape of a hollow sphere or ellipsoid; the best known member of the class is the archetypical “buckminsterfullerene” C60 that resembles a soccer ball (and is therefore often called “buckyball”). Dr. Cami and colleagues have recently discovered the unmistakable spectral signatures of the fullerene species C60 and C70 in Spitzer observations of a young planetary nebula, and these are now the largest molecules known to exist in space.

Jupiter Picture of the Day

The rich history of time-domain Jupiter data is of great value because it provides a whole new angle of attack, distinct from spatial-domain (imaging) data or from spectral-domain data. Time-domain Jupiter data provides a unique way to learn more about processes such as heat transport, atmospheric structure and evolution, composition, the formation of clouds and hazes, impact processes, and impactor populations. Dr.

The Search for Habitable Exoplanets in the Kepler Era and Beyond

For centuries people have wondered, “Are we alone?” With hundreds of planets now known to orbit other stars, we are finally able to begin answering the ancient questions, "Do other Earths exist? Are they common? Do any have signs of life? NASA's Kepler space telescope will soon tell us the statistical numbers of Earth-size planets orbiting sun-size stars. Beyond Kepler is the search for potentially habitable worlds around nearby, sun-like stars.

Detecting Circumbinary Planets

We discuss several techniques for the detection of circumbinary planets (CBP, planets that circle two stars at once). This involves detection by transits (which in the case of CBP produce a quasi-periodic signal), eclipsing binary (EB) timing, dynamical timing of EBs, and a new detection technique called the "eclipse echo" EE method. With all these acronyms the detection of CBP around EBs with the EE method should make NASA happy. : )

The oxygen isotopic composition of the Sun: implications for solar nebula chemistry

We have measured the oxygen isotopic composition of the solar wind, captured and returned to Earth by NASA's Genesis mission. The data demonstrate that the Earth, Moon, Mars, and bulk meteorites are depleted in 16O by ~7% relative to the bulk solar system in a non-mass-dependent manner. Gas phase photochemistry, occurring either in the solar nebula or in its progenitor molecular cloud, is most likely responsible for changing the isotopic composition of planetary materials in the inner solar system prior to planetesimal accretion.

Kepler and Doppler Searches for ExoEarths and Optical SETI

Science fiction portrays our Milky Way Galaxy as filled with habitable planets populated by advanced civilizations engaged in interstellar trade and conflict. Back in our real universe, Earth-like planets and alien life have proved elusive. Has science fiction led us astray? NASA has launched a space-borne telescope, Kepler, dedicated to discovering the first Earth-like worlds around other stars. The first results are startling and profound.

Analyzing the atmosphere of Super Earth GJ1214b

Astronomers currently know of over 500 planets orbiting distant stars beyond the confines of our solar system. Of these 500 "extrasolar" planets, most are large gas-rich planets, similar to Jupiter or Saturn. However, more recently, due to improvements in discovery techniques and instrumentation, astronomers have started to discover much smaller extrasolar planets, which are only slightly larger (or more massive) than the Earth. This new class of planets, which have masses of 1-10 times that of the Earth, have come to be known as super-Earths.

Planetary Observations with the James Webb Space Telescope

The James Webb Space Telescope is the next in the line of NASA's Great Observatories, a scientific successor to both the Hubble and Spitzer Space Telescopes. This space observatory will see the first galaxies to form in the universe, and explore how stars are born and give rise to planetary systems. It will study exoplanets, investigating their potential for life. JWST is optimized to detect infrared light, using a segmeted mirror more than 6 m in diameter and operating a million miles away in the cold, dark environment of Earth's Lagrange 2 point.

The Organism/Organics Exposure to Orbital Stresses (O/OREOS) NanoStatellite Mission

The O/OREOS (Organism/Organic Exposure to Orbital Stresses) nanosatellite is the first science demonstration mission of the NASA Astrobiology Small-Payloads Program. On November 19, 2010, O/OREOS was launched successfully to a high-inclination (72°), 650-km Earth orbit. O/OREOS consists of 3 conjoined cubesat (each 1000 cm3) modules: a control bus; the Space Environment Survivability of Living Organisms experiment, and the Space Environment Viability of Organics experiment.

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