72403025
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astroengine writes:
As NASA’s New Horizon’s spacecraft rapidly approaches Pluto for its historic flyby in July, the dwarf planet is gradually sliding into focus. And in the latest series of observations beamed back from the fringes of the Kuiper belt, surface features are becoming evident including the stunning revelation that Pluto may possess a polar ice cap. “As we approach the Pluto system we are starting to see intriguing features such as a bright region near Pluto’s visible pole, starting the great scientific adventure to understand this enigmatic celestial object,” said John Grunsfeld, associate administrator for NASA’s Science Mission Directorate in Washington D.C. “As we get closer, the excitement is building in our quest to unravel the mysteries of Pluto using data from New Horizons.”
72400635
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astroengine writes:
Astronomers have zoomed into an X-ray emission region immediately surrounding our galaxy’s supermassive black hole, gaining the highest X-ray resolution view to date, and it looks like they’ve stumbled on a mysterious place where stars go to die. Sagittarius A*, or Sgr A*, is the enigmatic compact radio source surrounding the supermassive black hole in the center of our galaxy. The black hole, which has a mass 4 million times that of our sun, dominates this region with its extreme gravitational well. Many efforts have been carried out in an attempt to understand the population of stars and other stellar phenomena in the immediate vicinity of Sgr A*, but resolving features from such an extreme environment at a distance of 25,000 light-years is not easy. Through measurements of X-ray spectra from the black hole’s neighborhood, however, astronomers are gradually adding some detail to Sgr A*’s landscape and in new research published in the journal Nature, it seems there’s a strange population of ‘dead’ stars accumulated in the black hole’s shadow.
72359017
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astroengine writes:
An airborne survey of a presumably dry Antarctic valley revealed a stunning and unexpected interconnected subsurface briny aquifer deep beneath the frozen tundra, a finding that not only has implications for understanding extreme habitats for life on Earth, but the potential for life elsewhere in the solar system, particularly Mars. The briny liquid — about twice as salty as seawater — was discovered about 200 miles underground in a region known as Taylor Valley. The aquifer is widespread, extending from the Ross Sea’s McMurdo Sound more than 11 miles into the eastern part of valley. A second system was found connecting Taylor Glacier with the ice-cover Lake Bonney. But the survey, which covered 114 square miles, may have just uncovered the proverbial tip of the iceberg.
72208367
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astroengine writes:
With the addition of a telescope at the southern-most point of Earth, the Event Horizon Telescope (EHT) now spans the diameter of our planet and, when the vast project goes online, astronomers will get their first glimpse of the bright ring surrounding a supermassive black hole. Using a method known as Very Long Baseline Interferometry, or VLBI, astronomers can combine the observing power of many telescopes situated at distant locations around the planet. The distance between those observatories, known as the “baseline,” then mimics a virtual telescope of that diameter. Now, in an attempt to make direct observations of the supermassive black hole in the center of our galaxy, located at a powerful radio emission source called Sagittarius A*, the South Pole Telescope (SPT) at the National Science Foundation’s Amundsen-Scott South Pole Station has been linked to the EHT and the stage is set for a historic new era of exploring the most extreme objects in the known universe. “Now that we’ve done VLBI with the SPT, the Event Horizon Telescope really does span the whole Earth, from the Submillimeter Telescope on Mount Graham in Arizona, to California, Hawaii, Chile, Mexico, Spain and the South Pole,” said Dan Marrone of the University of Arizona. “The baselines to SPT give us two to three times more resolution than our past arrays, which is absolutely crucial to the goals of the EHT. To verify the existence of an event horizon, the ‘edge’ of a black hole, and more generally to test Einstein’s theory of general relativity, we need a very detailed picture of a black hole. With the full EHT, we should be able to do this.”
72201597
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astroengine writes:
NASA kicked off a series of Hubble anniversary tributes Thursday by unveiling a new image taken by the telescope, which was launched into orbit on April 24, 1990. Managers chose a display of celestial fireworks in a giant cluster of stars known as Westerlund 2, located about 20,000 light-years away in the constellation Carina. The cluster, comprised of about 3,000 stars, is very young by astronomical standards, just about 2 million years old.
72091771
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astroengine writes:
At the furthest-most reaches of the observable universe lies one of the most enigmatic mysteries of modern cosmology: the cosmic microwave background (CMB) Cold Spot. Discovered in 2004, this strange feature etched into the primordial echo of the Big Bang has been the focus of many hypotheses — could it be the presence of another universe? Or is it just instrumental error? Now, astronomers may have acquired strong evidence as to the Cold Spot’s origin and, perhaps unsurprisingly, no multiverse hypothesis is required. But it’s not instrumental error either. It could be a vast "supervoid" around 1.8 billion light-years wide that is altering the characteristics of the CMB radiation traveling through it.
71938299
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astroengine writes:
A ghostly apparition has long been known to follow Saturn moon Enceladus in its orbit around the gas giant. But until now, scientists have had a hard time tracking its source. Using images from NASA’s Cassini mission, the source of these tendrils have been tracked down and they originate from the icy moon’s famous geysers. But even better than that, scientists have been able to track the tendril shapes down to the specific geysers that produce them. “We’ve been able to show that each unique tendril structure can be reproduced by particular sets of geysers on the moon’s surface,” said Colin Mitchell, a Cassini imaging team associate at the Space Science Institute in Boulder, Colo., and lead author of a paper published int he Astrophysical Journal. The study of these features are helping scientists understand how much ice is being transported into Saturn's E ring from Enceladus as well as helping us understand the evolution of the moon's sub-surface ocean.
71937965
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astroengine writes:
NASA’s MESSENGER spacecraft is in the final days of an unprecedented and unexpectedly long-lived, close-up study of the innermost planet of the solar system, with a crashing finale expected in two weeks. Out of fuel, the robotic Mercury Surface, Space Environment, Geochemistry and Ranging, or MESSENGER, probe on April 30 will succumb to the gravitational pull of this strange world that has been its home since March 2011. The purpose of the mission, originally designed to last one year, is to collect detailed geochemical and other data that will help scientists piece together of how Mercury formed and evolved. Mercury is one of four versions of rocky planets in the solar system, along with cloud-shrouded Venus, life-friendly Earth and dry, cold Mars. "MESSENGER is going to create a new crater on Mercury sometime in the near future ... let's not be sad about that," NASA associate administrator John Grunsfeld said Thursday.
71874445
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astroengine writes:
A new study carried out by the ESO’s Very Large Telescope and the NASA/ESA Hubble Space Telescope has revealed for the first time that dark matter may well interact with itself — a discovery that, at first glance, seems to contradict what we thought we knew about the nature of this invisible mass.
71834775
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astroengine writes:
Mars may be a frigid desert, but perchlorate salts in the planet’s soil are lowering the freezing temperature of water, setting up conditions for liquid brines to form at equatorial regions, new research from NASA’s Curiosity rover shows. The discovery of subsurface water, even a trickle, around the planets warmer equatorial belt defies current climate models, though spacecraft orbiting Mars have found geologic evidence for transient liquid water, a phenomenon termed “recurring slope lineae.” The findings, published in this week’s Nature Geoscience, are based on nearly two years worth of atmospheric humidity and temperature measurements collected by the roving science laboratory Curiosity, which is exploring an ancient impact basin called Gale Crater near the planet’s equator. The brines, computer models show, form nightly in the upper 2 inches of the planet’s soil as perchlorates absorb atmospheric water vapor. As temperatures rise in the morning, the liquid evaporates. The levels of liquid, however, are too low to support terrestrial-type organisms, the researchers conclude. “It is not just a problem of water, but also temperature. The water activity and temperatures are so low in Mars that they are beyond the limits of cell reproduction and metabolism,” Javier Martin-Torres, with Lulea University of Technology, in Kiruna, Sweden, wrote in an email to Discovery News.
71689371
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astroengine writes:
The primordial planet believed to have smashed into baby Earth, creating a cloud of debris that eventually formed into the moon, was chemically a near-match to Earth, a new study shows. The finding, reported in this week’s Nature, helps resolve a long-standing puzzle about why Earth and the moon are nearly twins in terms of composition. Computer models show that most of the material that formed the moon would have come from the shattered impactor, a planetary body referred to as Theia, which should have a slightly different isotopic makeup than Earth.
71689309
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astroengine writes:
Scientists have found complex organic molecules in a planet-forming disk of gas, dust and ice swirling around a very young star, evidence that the building blocks for life may be common in the universe. “We already knew that these disks are rich in water and simple organics. This is the first time we detect more complex organics,” astronomer Karin Oberg, with the Harvard-Smithsonian Center for Astrophysics, told Discovery News.
71654177
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astroengine writes:
For the first time, astronomers have combined the observational power of a ground-based survey with a space telescope to measure the distance to a stellar-mass object that was detected through a chance microlensing event. In a new paper published in The Astrophysical Journal, astronomer Jennifer Yee of the Harvard-Smithsonian Center for Astrophysics (CfA), Mass., led the study focusing on the detection of the microlensing event called “OGLE-2014-BLG-0939.” Detected by the 1.3 meter Warsaw Telescope at the Las Campanas Observatory in Chile and alerted through the Optical Gravitational Lens Experiment (OGLE) community on May 28, 2014, Yee’s team seized the opportunity to use NASA's Spitzer Space Telescope to focus on the transient brightening. Both telescopes recorded a light curve of the event and was therefore able to derive the distance to the dark lens.
71493859
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astroengine writes:
What better way to understand how to deflect an incoming asteroid than to smash into one to see what happens? This may sound like the storyline to a certain science fiction movie involving a team of oil drillers, but this is science fact, and Europe has started planning a mission to map a small target asteroid that NASA will attempt to shoot with a speeding spacecraft, no nukes required. As the first half of the joint Asteroid Impact & Deflection Assessment mission, the European Space Agency this month has started planning for the launch of its Asteroid Impact Mission (AIM) in October 2020. AIM’s target will be the binary asteroid system of Didymos, which is composed of a main 800 meter-wide hunk of space rock circled by a smaller 170 meter-wide asteroid informally known as “Didymoon.” It’s the smaller asteroid that the joint NASA/ESA mission is interested in bullying.
71051015
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astroengine writes:
The most powerful solar storm of the current solar cycle is currently reverberating around the globe. Initially triggered by the impact of a coronal mass ejection (CME) hitting our planet’s magnetosphere, a relatively mild geomagnetic storm erupted at around 04:30 UT (12:30 a.m. EDT), but it has since ramped-up to an impressive G4-class geomagnetic storm, priming high latitudes for some bright auroral displays.
