Tag Archives: astronomer

A Window into Europa’s Ocean Right at the Surface

By Guest PostMarch 8, 2013Scienceastronomer, california institute, chemical environment, chemical exchange, epsomite, europa, frozen exterior, galileo mission, icy moon, jet propulsion laboratory, johns hopkins university, kevin hand, liquid ocean, magnesium sulfate salt, mike brown, mineral, NASA, osiris spectrometer, oxidation, pasadena, potassium chlorides, salty ocean, sodium chloride, spectroscopic feature, surface of jupiter, Technology, voyager

If you could lick the surface of Jupiter’s icy moon Europa, you would actually be sampling a bit of the ocean beneath. A new paper by Mike Brown, an astronomer at the California Institute of Technology in Pasadena, Calif., and Kevin Hand from NASA’s Jet Propulsion Laboratory, also in Pasadena, details the strongest evidence yet that salty water from the vast liquid ocean beneath Europa’s frozen exterior actually makes its way to the surface.

The finding, based on some of the best data of its kind since NASA’s Galileo mission (1989 to 2003) to study Jupiter and its moons, suggests there is a chemical exchange between the ocean and surface, making the ocean a richer chemical environment. The work is described in a paper that has been accepted for publication in the Astronomical Journal. (more…)

Texas Astronomers Measure Most Massive, Most Unusual Black Hole Using Hobby-Eberly Telescope

By Guest PostNovember 29, 2012Scienceastronomer, austin, bosch, constellation perseus, elliptical, Galaxy, galaxy mass, het data, hobby eberly telescope, karl gebhardt, lenticular galaxy, mass, massive black hole, massive galaxy survey, mcdonald observatory, Milky Way, neptune, ngc 1277, oddball galaxy, pennsylvania state university, remco, sun mass, texas, university, van den

FORT DAVIS, Texas — Astronomers have used the Hobby-Eberly Telescope at The University of Texas at Austin’s McDonald Observatory to measure the mass of what may be the most massive black hole yet — 17 billion times our sun’s mass — in galaxy NGC 1277. The unusual black hole makes up 14 percent of its galaxy’s mass, rather than the usual 0.1 percent. This galaxy and several more in the same study could change theories about how black holes and galaxies form and evolve. The work will appear in the journal Nature on Nov. 29.

NGC 1277 lies 220 million light-years away in the constellation Perseus. The galaxy is only 10 percent the size and mass of our Milky Way. Despite NGC 1277’s diminutive size, the black hole at its heart is more than 11 times as wide as Neptune’s orbit around the sun. (more…)

Astronomers Pin Down Origins of “Mile Markers” for Expansion of Universe

By Guest PostNovember 24, 2012Scienceastronomer, ben shappee, brightness, chemical element, dead stars, kris stanek, lbt, mile markers, mods system, mods1, ohio state university, optical telescope, origin, pattern, pinwheel galaxy, rick pogge, supernova 2011fe, supernovae, type ia, white dwarfs, zombies

COLUMBUS, Ohio – A study using a unique new instrument on the world’s largest optical telescope has revealed the likely origins of especially bright supernovae that astronomers use as easy-to-spot “mile markers” to measure the expansion and acceleration of the universe.

In a paper to appear in the Astrophysical Journal, researchers describe observations of recent supernova 2011fe that they captured with the Large Binocular Telescope (LBT) using a tool created at Ohio State University: the Multi-Object Double Spectrograph (MODS). (more…)

How Galaxies Grow Up

By Guest PostOctober 20, 2012Scienceadam block, age, andromeda galaxy, astronomer, benjamin weiner, blue galaxies, california, computer program, computer simulation, deep2, emission line, galaxies, Galaxy, galaxy evolution, galaxy population, galaxy type, gas, grow up, hawaii, internal motion, keck telescopes, lick observatory, light years, m88 galaxy, massive system, Milky Way, mount lemmon, NASA, observational data, random motion, redshift survey, rotation speed, santa cruz, skycenter, spiral disk shape, star forming galaxies, susan kassin, ua, universe, university, velocity

A study of 544 star-forming galaxies shows that disk galaxies like our own Milky Way reached their current state as orderly rotating pinwheels much later than previously thought, long after much of the universe’s star formation had ceased.

Galaxies are in no hurry to grow up, a team of astronomers has discovered. A comprehensive study of hundreds of galaxies observed by the Keck telescopes in Hawaii and NASA’s Hubble Space Telescope has revealed an unexpected pattern of change that extends back 8 billion years, or more than half the age of the universe.

Researchers say the distant blue galaxies they studied are gradually transforming into rotating disk galaxies like our own Milky Way. Until now, it had not been clear how a galaxy’s organization and internal motion change over time, said Benjamin Weiner, assistant astronomer at the UA Steward Observatory and co-author of the paper describing the findings, which are published in The Astrophysical Journal. (more…)

Bounce, Skid, Wobble: How Huygens Landed on Titan

By Guest PostOctober 11, 2012Science17th century, analysis, astronomer, cassini spacecraft, christiaan huygens, direction, dutch, earth, erich karkoschka, european, evaporate, friction, hazy atmosphere, horizon, huygens data, huygens impact, huygens probe, institute, lower atmosphere, max planck, methane, model, moon, moon surface, motion, mud like, NASA, nicolas altobelli, organic aerosols, ralph lorenz, saturn, space agency, splat, stefan schroder, substance, titan, titan atmosphere, undisturbed terrain

Piecing together the events of the farthest touchdown a manmade spacecraft has ever made on an alien world reveals new clues about Titan’s surface and helps plan future missions to moons and planets.

The Huygens probe, ferried to Saturn’s moon Titan by NASA’s Cassini spacecraft, bounced, slid and wobbled its way to rest in the 10 seconds after touching down on Titan in January 2005, a new analysis reveals. The moon’s surface is more complex than previously thought.

Scientists reconstructed the chain of events by analyzing data from a variety of instruments that were active during the impact, in particular changes in the acceleration experienced by the probe. The probe was supplied by the European Space Agency and named after the Dutch 17th century astronomer Christiaan Huygens. (more…)

MSU Research Sheds New Light on Star Clusters, Black Holes

By Guest PostOctober 7, 2012Scienceanil seth, array telescope, astronomer, black hole, density, earth, Environment, Galaxy, globular cluster, gravitational dance, hubble, james miller jones, jay strader, laura chomiuk, light year, m22, messier 22, michigan, Milky Way, new mexico, radio observation, radio wavelength, research, space telescope, star, star cluster, state university, thomas maccarone, university, utah, very large, xray

EAST LANSING, Mich. — Research by Michigan State University astronomers has scientists re-thinking the fates of black holes, particularly in groups of stars known as globular clusters.

The research of Jay Strader, MSU assistant professor of physics and astronomy, and colleagues focused on a cluster called Messier 22, or M22, a collection of hundreds of thousands of stars located about 10,000 light years from Earth. Using images of unprecedented depth observed at radio wavelengths, Strader and his team were surprised to find not one but two black holes in the cluster. (more…)

Infant Galaxy Offers Peek at Early Universe

By Guest PostSeptember 25, 2012Science1149 jd, astronomer, big bang, clash, cluster, cosmic, dark matter, Galaxy, gravitational lens, gravity, hubble telescope, light, macs, mass, megan donahue, michigan, Milky Way, NASA, northern hemisphere, object, ordinary galaxy, sky, space telescope, spitzer, state university, universe, zoom lens

EAST LANSING, Mich. — A Michigan State University astronomer is part of an international team of scientists that has discovered a galaxy so far, far away that its light was emitted not all that long after the Big Bang occurred.

The research of MSU’s physics and astronomy professor Megan Donahue and colleagues is detailed in the recent issue of the journal Nature. They found that this galaxy began emitting light “just” 490 million years after the Big Bang, when the universe was only 3.6 percent of its present age. (more…)

First Stars, Galaxies Formed more Rapidly than Expected

By Guest PostSeptember 9, 2012Scienceanalysis, anisotropy probe, Antarctica, astronomer, background, Berkeley, california, christian reichardt, cmb, cosmic microwave, cosmological evolution, data, earth axis, electron, Epoch, Galaxy, geographic, herschel satellite, high resolution, hydrogen atom, image, john carlstrom, kavli foundation, microwave, millimeter wavelength, national, neutral, neutral gas, oliver zahn, period, plasma, polar plateau, proton, radiation, reionization, s chandrasekhar, science foundation, south pole, star, telescope, ultraviolet light, universe, university, wilkinson

Analysis of data from the National Science Foundation’s South Pole Telescope, for the first time, more precisely defines the period of cosmological evolution when the first stars and galaxies formed and gradually illuminated the universe. The data indicate that this period, called the epoch of reionization, was shorter than theorists speculated — and that it ended early.

“We find that the epoch of reionization lasted less than 500 million years and began when the universe was at least 250 million years old,” said Oliver Zahn, a postdoctoral fellow at the Berkeley Center for Cosmological Physics at the University of California, Berkeley, who led the study. “Before this measurement, scientists believed that reionization lasted 750 million years or longer, and had no evidence as to when reionization began.” (more…)