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How Did Earth’s Primitive Chemistry Get Kick Started?

By Guest PostAugust 2, 2013Scienceacetate, alkaline hydrothermal fluids, alkaline hydrothermal vents, ancient enzymes, atlantic ocean, bottom of oceans, chemical signature, distribution, earliest oceans, earth, enceladus, evolution, floor, future of life, hypothesis, icy worlds, jupiter, lauren white, laws of thermodynamics, mike russell, moon europa, nano engines, NASA, organic carbon, origin, polymers, primitive chemistry, saturn

How did life on Earth get started? Three new papers co-authored by Mike Russell, a research scientist at NASA’s Jet Propulsion Laboratory, Pasadena, Calif., strengthen the case that Earth’s first life began at alkaline hydrothermal vents at the bottom of oceans. Scientists are interested in understanding early life on Earth because if we ever hope to find life on other worlds — especially icy worlds with subsurface oceans such as Jupiter’s moon Europa and Saturn’s Enceladus — we need to know what chemical signatures to look for.

Two papers published recently in the journal Philosophical Transactions of the Royal Society B provide more detail on the chemical and precursor metabolic reactions that have to take place to pave the pathway for life. Russell and his co-authors describe how the interactions between the earliest oceans and alkaline hydrothermal fluids likely produced acetate (comparable to vinegar). The acetate is a product of methane and hydrogen from the alkaline hydrothermal vents and carbon dioxide dissolved in the surrounding ocean. Once this early chemical pathway was forged, acetate could become the basis of other biological molecules. They also describe how two kinds of “nano-engines” that create organic carbon and polymers — energy currency of the first cells — could have been assembled from inorganic minerals. (more…)

Water Geysers on Saturn’s Moon

By Guest PostAugust 1, 2013Sciencecassini spacecraft, christophe sotin, cornell university, data, enceladus, enceladus plume, galileo, gravity, hydrocarbon composition, icy surface, instrument, ithaca, jet propulsion laboratory, linda spilker, matt hedman, moon, moon of saturn, NASA, organic material, robert brown, saturn, saturn gravity, saturnian moon, seismological signs, tiger stripes, titan, university of arizona, vims, water geysers

A new study published in Nature this week describes the forces that control the jets of water and organic material that erupt from the icy surface of Enceladus, a moon of Saturn. UA scientists contributed data to the study.

The intensity of the jets of water ice and organic molecules that shoot out from Saturn’s moon Enceladus depends on the moon’s proximity to the planet, according to data obtained by NASA’s Cassini spacecraft. The finding, detailed in the journal Nature this week, is the first clear observation that shows the Enceladus plume varies in a predictable manner. (more…)

How Mars’ atmosphere got so thin: New insights from Curiosity

By Guest PostJuly 29, 2013Scienceadditional neutron, carbon 12, carbon 13, carbon isotope, curiosity rover, heavier stable isotope, insights from curiosity, isotopes, lighter isotopes, mahli, mars atmosphere, martian air, NASA, sam, samples, solar system, sushil atreya, thin, university of michigan

ANN ARBOR — New findings from NASA’s Curiosity rover provide clues to how Mars lost its original atmosphere, which scientists believe was much thicker than the one left today.

“The beauty of these measurements lies in the fact that these are the first really high-precision measurements of the composition of Mars’ atmosphere,” said Sushil Atreya, professor of atmospheric, oceanic and space sciences at the University of Michigan. (more…)

NASA Releases Images of Earth by Distant Spacecraft

By Guest PostJuly 24, 2013Sciencecarolyn porco, cassini images earth, cassini spacecraft, columbia university, coming of age, distant spacecraft, images of earth, linda spilker, mercury, messenger, moon, NASA, nasa interplanetary spacecraft, photo of earth, planetary explorers, saturns rings, sean solomon, wide angle image

PASADENA, Calif. — Color and black-and-white images of Earth taken by two NASA interplanetary spacecraft on July 19 show our planet and its moon as bright beacons from millions of miles away in space.

NASA’s Cassini spacecraft captured the color images of Earth and the moon from its perch in the Saturn system nearly 900 million miles (1.5 billion kilometers) away. MESSENGER, the first probe to orbit Mercury, took a black-and-white image from a distance of 61 million miles (98 million kilometers) as part of a campaign to search for natural satellites of the planet. (more…)

Solar tsunami used to measure Sun’s magnetic field

By Guest PostJuly 20, 2013Scienceatmosphere, cmes, coronal mass ejections, david long, earth, eis, explosion, extreme, japanese hinode spacecraft, magnetic field, measure, NASA, satellite, sdo, solar activity, solar dynamics observatory, solar storms, solar tsunami, sun, technological infrastructure, ultraviolet, ultraviolet imaging spectrometer, xray

A solar tsunami observed by NASA’s Solar Dynamics Observatory (SDO) and the Japanese Hinode spacecraft has been used to provide the first accurate estimates of the Sun’s magnetic field.

Solar tsunamis are produced by enormous explosions in the Sun’s atmosphere called coronal mass ejections (CMEs). As the CME travels out into space, the tsunami travels across the Sun at speeds of up to 1000 kilometres per second.

Similar to tsunamis on Earth, the shape of solar tsunamis is changed by the environment through which they move. Just as sound travels faster in water than in air, solar tsunamis have a higher speed in regions of stronger magnetic field. This unique feature allowed the team, led by researchers from UCL’s Mullard Space Science Laboratory, to measure the Sun’s magnetic field. The results are outlined in a paper soon to be published in the journal Solar Physics. (more…)

In the Zone: How Scientists Search for Habitable Planets

By Guest PostJuly 18, 2013Scienceatmosphere, exoplanets, goldilocks planets, habitable planets, habitable zone, kepler 69c, kepler mission, liquid water, lucianne walkowicz, NASA, penn state university, radiation, ravi kumar kopparapu, scientists, search, solar system, star, stephen kane, super earth, super venus planet, total energy output, venus like planet

There is only one planet we know of, so far, that is drenched with life. That planet is Earth, as you may have guessed, and it has all the right conditions for critters to thrive on its surface. Do other planets beyond our solar system, called exoplanets, also host life forms?

Astronomers still don’t know the answer, but they search for potentially habitable planets using a handful of criteria. Ideally, they want to find planets just like Earth, since we know without a doubt that life took root here. The hunt is on for planets about the size of Earth that orbit at just the right distance from their star – in a region termed the habitable zone. (more…)

Cloud modeling expands estimate of life-supporting planets

By Guest PostJuly 2, 2013Sciencebrazil, cloud cover, cloud modeling, dark side, dorian abbot, dwarf stars, earth like planets, earth size planet, global climate simulation, indonesia, james webb, jun yang, kepler mission, larger habitable zone, life supporting planets, milky way galaxy, NASA, nicolas cowan, northwestern university, one dimensional, space telescope, sub stellar region, thermostat, university of chicago

Larger habitable zone suggests 60 billion planets could sustain water, life

A new study that calculates the influence of cloud behavior on climate doubles the number of potentially habitable planets orbiting red dwarfs, the most common type of star in the universe. This finding means that in the Milky Way galaxy alone, 60 billion planets may be orbiting red dwarf stars in the habitable zone.

Researchers at the University of Chicago and Northwestern University based their study, which appears in Astrophysical Journal Letters, on rigorous computer simulations of cloud behavior on alien planets. This cloud behavior dramatically expanded the estimated habitable zone of red dwarfs, which are much smaller and fainter than stars like the sun. (more…)

NASA’s Voyager 1 Explores Final Frontier of Our ‘Solar Bubble’

By Guest PostJune 29, 2013Sciencecharged particles, cosmic ray, depletion region, ed stone, energetic particle data, final frontier, heliosphere, interstellar arrival, interstellar space, johns hopkins university, jupiter, leonard burlaga, magnetic field, magnetosphere, Milky Way, NASA, solar bubble, solar originating particles, stamatios krimigis, twin spacecraft, voyager 1, voyager project scientist

PASADENA, Calif. — Data from Voyager 1, now more than 11 billion miles (18 billion kilometers) from the sun, suggest the spacecraft is closer to becoming the first human-made object to reach interstellar space.

Research using Voyager 1 data and published in the journal Science today provides new detail on the last region the spacecraft will cross before it leaves the heliosphere, or the bubble around our sun, and enters interstellar space. Three papers describe how Voyager 1’s entry into a region called the magnetic highway resulted in simultaneous observations of the highest rate so far of charged particles from outside heliosphere and the disappearance of charged particles from inside the heliosphere. (more…)

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