Swirling, stormy clouds may be ever-present on cool celestial orbs called brown dwarfs. New observations from NASA’s Spitzer Space Telescope suggest that most brown dwarfs are roiling with one or more planet-size storms akin to Jupiter’s “Great Red Spot.”
“As the brown dwarfs spin on their axis, the alternation of what we think are cloud-free and cloudy regions produces a periodic brightness variation that we can observe,” said Stanimir Metchev of the University of Western Ontario, Canada. “These are signs of patchiness in the cloud cover.” (more…)
AUSTIN, Texas — In a finding of relevance to the search for life in our solar system, researchers at The University of Texas at Austin’s Institute for Geophysics, the Georgia Institute of Technology, and the Max Planck Institute for Solar System Research have shown that the subsurface ocean on Jupiter’s moon Europa may have deep currents and circulation patterns with heat and energy transfers capable of sustaining biological life.
Scientists believe Europa is one of the planetary bodies in our solar system most likely to have conditions that could sustain life, an idea reinforced by magnetometer readings from the Galileo spacecraft detecting signs of a salty, global ocean below the moon’s icy shell. (more…)
Astronomers have discovered a “weird and freakish object” resembling a rotating lawn sprinkler in the asteroid belt between Mars and Jupiter. The find, reported online in the Nov. 7 issue of the Astrophysical Journal Letters, has left them scratching their heads and searching for an explanation for the strange asteroid’s out-of-this-world appearance.
Normal asteroids appear simply as tiny points of light. This bizarre asteroid has six comet-like tails of dust radiating from it like spokes on a wheel. (more…)
Most of what scientists know of Jupiter’s moon Europa they have gleaned from a dozen or so close flybys from NASA’s Voyager 2 spacecraft in 1979 and NASA’s Galileo spacecraft in the mid-to-late 1990s. Even in these fleeting, paparazzi-like encounters, scientists have seen a fractured, ice-covered world with tantalizing signs of a liquid water ocean under its surface. Such an environment could potentially be a hospitable home for microbial life. But what if we got to land on Europa’s surface and conduct something along the lines of a more in-depth interview? What would scientists ask? A new study in the journal Astrobiology authored by a NASA-appointed science definition team lays out their consensus on the most important questions to address.
“If one day humans send a robotic lander to the surface of Europa, we need to know what to look for and what tools it should carry,” said Robert Pappalardo, the study’s lead author, based at NASA’s Jet Propulsion Laboratory, Pasadena, Calif. “There is still a lot of preparation that is needed before we could land on Europa, but studies like these will help us focus on the technologies required to get us there, and on the data needed to help us scout out possible landing locations. Europa is the most likely place in our solar system beyond Earth to have life today, and a landed mission would be the best way to search for signs of life.” (more…)
AUSTIN, Texas — Scientists at the University of Texas at Austin’s Institute for Geophysics helped develop a blueprint for a possible future NASA lander mission to Europa, an icy moon of Jupiter that has a global ocean covered by an ice shell. Europa’s large reservoir of liquid water has long enchanted planetary scientists with the possibility of harboring life. Many experts believe it to be the most likely place in our solar system besides Earth to host life today. The proposed mission is designed to assess the moon’s habitability by studying its surface composition, ice shell, ocean and geology.
Don Blankenship, senior research scientist at the institute, is part of the science definition team commissioned by NASA to draft the report, which appears in the August 2013 issue of Astrobiology. Blankenship and two colleagues — Krista Soderlund, postdoctoral fellow at the institute; and Britney Schmidt, formerly a postdoctoral fellow at the institute, now assistant professor at the Georgia Institute of Technology — developed a part of the mission scenario that would use sound waves to study the moon’s icy shell, deep ocean and possible shallow lakes. (more…)
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…)
PASADENA, Calf. — The true identity of centaurs, the small celestial bodies orbiting the sun between Jupiter and Neptune, is one of the enduring mysteries of astrophysics. Are they asteroids or comets? A new study of observations from NASA’s Wide-field Infrared Survey Explorer (WISE) finds most centaurs are comets.
Until now, astronomers were not certain whether centaurs are asteroids flung out from the inner solar system or comets traveling in toward the sun from afar. Because of their dual nature, they take their name from the creature in Greek mythology whose head and torso are human and legs are those of a horse. (more…)
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…)
