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Categories: Mathematics: Statistics, Space: The Solar System
Published MESSENGER's endgame: Hover campaign promises bird's-eye view of Mercury's surface


MESSENGER will not go gentle into that good night. The mission will end sometime this spring, when the spacecraft runs out of propellant and the force of solar gravity causes it to impact the surface of Mercury. But the team initiated a "hover" observation campaign designed to gather scientific data from the planet at ultra-low altitudes until the last possible moment. Engineers have devised a series of orbit-correction maneuvers (OCMs) over the next five weeks -- the first of which was carried out today -- designed to delay the inevitable impact a bit longer.
Published Mercury: Results from Messenger’s low-altitude campaign


NASA's MESSENGER mission, now nearing the end of its fourth and final year of orbital operations at Mercury, is well into a low-altitude campaign that is returning images and measurements of the planet's surface and interior that are unprecedented in their resolution.
Published New Mercury surface composition maps illuminate the planet's history


Scientists have created global-scale maps of Mercury's surface chemistry that reveal previously unrecognized geochemical terranes -- large regions that have compositions distinct from their surroundings. The presence of these large terranes has important implications for the history of the planet
Published Venus, if you will, as seen in radar with the Green Bank Telescope


Recently, by combining the highly sensitive receiving capabilities of the National Science Foundation's Green Bank Telescope and the powerful radar transmitter at the NSF's Arecibo Observatory, astronomers were able to make remarkably detailed images of the surface of Venus without ever leaving Earth.
Published NASA spacecraft becomes first to orbit a dwarf planet


NASA's Dawn spacecraft has become the first mission to achieve orbit around a dwarf planet. The spacecraft was approximately 38,000 miles (61,000) kilometers from Ceres when it was captured by the dwarf planet's gravity at about 4:39 a.m. PST (7:39 a.m. EST) Friday.
Published Ancient star system reveals Earth-sized planets forming near start of universe


A Sun-like star with orbiting planets, dating back to the dawn of the Galaxy, has been discovered by an international team of astronomers. At 11.2 billion years old, it is the oldest star with Earth-sized planets ever found and proves that such planets have formed throughout the history of the Universe.
Published New research re-creates planet formation, super-Earths and giant planets in the laboratory


New laser-driven compression experiments reproduce the conditions deep inside exotic super-Earths and giant planet cores, and the conditions during the violent birth of Earth-like planets, documenting the material properties that determined planets' formation and evolution processes.
Published Dawn spacecraft delivers new image of dwarf planet Ceres


As NASA's Dawn spacecraft closes in on Ceres, new images show the dwarf planet at 27 pixels across, about three times better than the calibration images taken in early December. These are the first in a series of images that will be taken for navigation purposes during the approach to Ceres.
Published Origin of long-standing space mystery revealed: Origin of the 'theta aurora'


Scientists have solved a long-standing space mystery -- the origin of the 'theta aurora'. Auroras are the most visible manifestation of the Sun's effect on Earth. They are seen as colorful displays in the night sky, known as the Northern or Southern Lights. They are caused by the solar wind, a stream of plasma -- electrically charged atomic particles -- carrying its own magnetic field, interacting with the earth's magnetic field. Normally, the main region for this impressive display is the 'auroral oval', which lies at around 65-70 degrees north or south of the equator, encircling the polar caps. However, auroras can occur at even higher latitudes. One type is known as a 'theta aurora' because seen from above it looks like the Greek letter theta -- an oval with a line crossing through the center.
Published MESSENGER data suggest recurring meteor shower on Mercury


The closest planet to the sun appears to get hit by a periodic meteor shower, possibly associated with a comet that produces multiple events annually on Earth. The clues pointing to Mercury's shower were discovered in the very thin halo of gases that make up the planet's exosphere, which is under study by NASA's MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft.
Published NASA Voyager: 'Tsunami wave' still flies through interstellar space


The Voyager 1 spacecraft has experienced three shock waves. The most recent shock wave, first observed in February 2014, still appears to be going on. One wave, previously reported, helped researchers determine that Voyager 1 had entered interstellar space.
Published Amateur, professional astronomers alike thrilled by extreme storms on Uranus


The normally bland face of Uranus has become increasingly stormy, with enormous cloud systems so bright that for the first time, amateur astronomers are able to see details in the planet's hazy blue-green atmosphere. Astronomers first observed the storms in the infrared using the Keck telescope. When amateurs learned of the storms, they turned their optical telescopes on the planet and saw different but equally impressive storms.
Published Space enthusiasts are being given the rare opportunity to name a planet


Several organizations are eligible to name one of 20 to 30 planets, and their host stars, in a unique competition organized by the International Astronomical Union (IAU). The scheme gives members of the public the chance to name the newly discovered ExoWorlds (which have all been identified and confirmed since 2008).
Published NASA's SDO observes largest sunspot of the solar cycle


On Oct. 18, 2014, a sunspot rotated over the left side of the sun, and soon grew to be the largest active region seen in the current solar cycle, which began in 2008. Currently, the sunspot is almost 80,000 miles across -- ten Earth's could be laid across its diameter.
Published Heavy metal frost? A new look at a Venusian mystery


Venus is hiding something beneath its brilliant shroud of clouds: a first order mystery about the planet that researchers may be a little closer to solving because of a new re-analysis of twenty-year-old spacecraft data. Venus's surface can't be seen from orbit in visible light because of the planet's hot, dense, cloudy atmosphere. Instead, radar has been used by spacecraft to penetrate the clouds and map out the surface – both by reflecting radar off the surface to measure elevation and by looking at the radio emissions of the hot surface. The last spacecraft to map Venus in this way was Magellan, two decades ago.
Published Astronomers spot faraway Uranus-like planet: First 'ice giant' planet found in another solar system


Our view of other solar systems just got a little more familiar, with the discovery of a planet 25,000 light-years away that resembles our own Uranus. Astronomers have discovered hundreds of planets around the Milky Way, including rocky planets similar to Earth and gas planets similar to Jupiter. But there is a third type of planet in our solar system -- part gas, part ice -- and this is the first time anyone has spotted a twin for our so-called "ice giant" planets, Uranus and Neptune.
Published Rediscovering Venus to find faraway Earths: Measuring gravitational pull of a planet should speed search


As the search for Earth-like planets wages on, a team of researchers may have found a way to speed up the process. The team is developing a new laser-based technology known as the green astro-comb to obtain information about the mass of a distant planet. Using this information, astronomers will be able to determine whether distant exoplanets are rocky worlds like Earth or less dense gas giants like Jupiter.
Published The origin of Uranus and Neptune elucidated


Astronomers have just proposed a solution to the problematic chemical composition of Uranus and Neptune, thus providing clues for understanding their formation. The researchers focused on the positioning of these two outermost planets of the Solar System, and propose a new model explaining how and where they formed.
Published Miranda: An icy moon deformed by tidal heating


Miranda, a small, icy moon of Uranus, is one of the most visually striking and enigmatic bodies in the solar system. Despite its relatively small size, Miranda appears to have experienced an episode of intense resurfacing that resulted in the formation of at least three remarkable and unique surface features -- polygonal-shaped regions called coronae.
Published Unraveling mysteries of the Venusian atmosphere


Underscoring the vast differences between Earth and its neighbor Venus, new research shows a glimpse of giant holes in the electrically charged layer of the Venusian atmosphere, called the ionosphere. The observations point to a more complicated magnetic environment than previously thought -- which in turn helps us better understand this neighboring, rocky planet.