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Mars Base

Astronomers discover planet that shouldn't be there - 0 views

phys.org/...tronomers-planet-shouldnt.html

scibyte112 exoplanet

shared by Mars Base on 06 Dec 13 - No Cached
  • An international team of astronomers
  • has discovered the most distantly orbiting planet found to date around a single, sun-like star
  • 11 times Jupiter's mass and orbiting its star at 650 times the average Earth-Sun distance
  • ...34 more annotations...
  • HD 106906 b
  • throws a wrench in planet formation theories
  • no model of either planet or star formation fully explains what we see
  • It is thought that planets close to their stars, like Earth, coalesce from small asteroid-like bodies born in the primordial disk of dust and gas that surrounds a forming star
  • this process acts too slowly to grow giant planets far from their star
  • Another proposed mechanism is that giant planets can form from a fast, direct collapse of disk material
  • primordial disks rarely contain enough mass in their outer reaches to allow a planet like HD 106906 b to form
  • Several alternative hypotheses have been put forward, including formation like a mini binary star system
  • binary star system can be formed when two adjacent clumps of gas collapse more or less independently to form stars, and these stars are close enough to each other to exert a mutual gravitation attraction and bind them together in an orb
  • It is possible that in the case of the HD 106906 system the star and planet collapsed independently from clumps of gas, but for some reason the planet's progenitor clump was starved for material and never grew large enough to ignite and become a star
  • one problem with this scenario is that the mass ratio of the two stars in a binary system is typically no more than 10-to-1.
  • the mass ratio is more than 100-to-1,
  • extreme mass ratio is not predicted from binary star formation theories – just like planet formation theory predicts that we cannot form planets so far from the host star
  • is also of
  • interest because researchers can still detect the remnant "debris disk" of material left over from planet and star formation.
  • potential to help us disentangle the various formation models
  • Future observations of the planet's orbital motion and the primary star's debris disk may help answer that question
  • At only 13 million years old, this young planet still glows from the residual heat of its formation
  • Because at 2,700 Fahrenheit (about 1,500 degrees Celsius) the planet is much cooler than its host star
  • it emits most of its energy as infrared rather than visible light
  • Earth
  • formed 4.5 billion years ago
  • about 350 times older than HD 106906 b.
  • Direct imaging observations require exquisitely sharp images, akin to those delivered by the Hubble Space Telescope
  • To reach this resolution from the ground requires a technology called Adaptive Optics, or AO
  • The team used the new Magellan Adaptive Optics (MagAO) system and Clio2 thermal infrared camera
  • mounted on the 6.5 meter-diameter Magellan telescope in the Atacama Desert in Chile to take the discovery image
  • MagAO was able to utilize its special Adaptive Secondary Mirror
  • 585 actuators, each moving 1,000 times a second, to remove the blurring of the atmosphere
  • optimized for thermal infrared wavelengths, where giant planets are brightest compared to their host stars
  • planets are most easily imaged at these wavelengths
  • The team was able to confirm that the planet is moving together with its host star by examining Hubble Space Telescope data taken eight years prior for another research program
  • This planet discovery is particularly exciting because it is in orbit so far from its parent star. This leads to many
  • questions about its formation history and composition
Mars Base

Astronomers find sun's 'long-lost brother,' pave way for family reunion -- ScienceDaily - 0 views

www.sciencedaily.com/...140510151703.htm

scibyte130 sun

shared by Mars Base on 11 May 14 - No Cached
  • Astronomers have identified
  • a star that was almost certainly born from the same cloud of gas and dust as our star.
  • The newly developed methods for locating the Sun's 'siblings' will help other astronomers find other "solar siblings," work that could lead to an understanding of how and where our Sun formed, and how our solar system became hospitable for life
  • ...28 more annotations...
  • team of researcher
  • has identified the first "sibling" of the Sun -- a star that was almost certainly born from the same cloud of gas and dust as our star
  • there is a chance, "small, but not zero," Ramirez said, that these solar sibling stars could host planets that harbor life
  • The solar sibling his team identified is a star called HD 162826, a star 15 percent more massive than the Sun, located 110 light-years away in the constellation Hercules
  • The star is not visible to the unaided eye, but easily can be seen with low-power binoculars, not far from the bright star Vega.
  • The team identified HD 162826 as the Sun's sibling by following up on 30 possible candidates found by several groups around the world looking for solar siblings.
  • All of these observations used high-resolution spectroscopy to get a deep understanding of the stars' chemical make-up.
  • several factors are needed to really pin down a solar sibling
  • . In addition to chemical analysis, his team also included information about the stars' orbits
  • where they had been and where they are going in their paths around the center of the Milky Way galaxy
  • Combining information on both chemical make-up and dynamics of the candidates narrowed the field down to one: HD 162826.
  • By "lucky coincidence,"
  • this star has been studied by the McDonald Observatory Planet Search team
  • for more than 15 years
  • Those studies,
  • together with calculations
  • have ruled out any "hot Jupiters" -- massive planets orbiting close to the star
  • The studies indicate that it's unlikely that a Jupiter analog orbits the star, either, but they do not rule out the presence of smaller terrestrial planets.
  • the project has a larger purpose: to create a road map for how to identify solar siblings
  • "The idea is that the Sun was born in a cluster with a thousand or a hundred thousand stars. This cluster, which formed more than 4.5 billion years ago, has since broken up,"
  • Ivan Ramirez/Tim Jones/McDonald
  • The member stars have broken off into their own orbits around the galactic center, taking them to different parts of the Milky Way today. A few, like HD 162826, are still nearby. Others are much farther
  • even with information on more stars to work with, it's not like "we're going to throw this data into a machine and it's going to spit out the answer,"
  • "You can concentrate on certain key chemical elements that are going to be very useful
  • ." These elements are ones that vary greatly among stars which otherwise have very similar chemical compositions.
  • team has identified the elements barium and yttrium as particularly useful.
  • Once many more solar siblings have been identified, astronomers will be one step closer to knowing where and how the Sun formed.
  • To reach that goal, the dynamics specialists will make models that run the orbits of all known solar siblings backward in time, to find where they intersect: their birthplace.
Mars Base

Discovery of two types of neutron stars points to two different classes of supernovae - 0 views

www.physorg.com/...-stars-classes-supernovae.html

neutron stars scibyte21

shared by Mars Base on 10 Nov 11 - No Cached
  • Neutron stars are the last stage in the evolution of many massive stars
  • the mass of a single neutron star exceeds that of the entire sun, but squeezed into a ball whose diameter is smaller than that of London
  • to reveal how they have discovered two distinct populations of neutron stars that appear to have formed via two different supernova channels
  • ...10 more annotations...
  • speculated before about the possible existence of different types of neutron stars, but there has never been any clear observational evidence that there is really more than one type
  • astronomers analysed data on a large sample of high-mass X-ray binaries
  • double star systems in which a fast-spinning neutron star orbits a massive young companion
  • neutron star in these systems also periodically siphons off material from its partner
  • neutron star becomes an X-ray pulsar
  • because by timing their pulses, astronomers can accurately measure the neutron star spin periods
  • detected two distinct groupings in a large set of spin periods measured in this way
  • one group of neutron stars typically spinning once every 10 seconds
  • the other once every 5 minutes
  • led them to conclude that the two distinct neutron star populations formed via two different supernova channels
Mars Base

'Runaway' Star Cluster Breaks Free from Distant Galaxy - 0 views

www.universetoday.com/...reaks-free-from-distant-galaxy

scibyte129 StarCluster

shared by Mars Base on 01 May 14 - No Cached
  • discovered dozens of so-called “hypervelocity stars” — single stars that break the stellar speed limit
  • The Virgo Cluster galaxy, M87, has ejected an entire star cluster, throwing it toward us at more than two million miles per hour.
  • Astronomers have found runaway stars before, but this is the first time we’ve found a runaway star cluster
  • ...10 more annotations...
  • About one in a billion stars travel at a speed roughly three times greater than our Sun
  • at 220 km/s with respect to the galactic center
  • At a speed that fast, these stars can easily escape the galaxy entirely, traveling rapidly throughout intergalactic space.
  • this is the first time an entire star cluster has broken free
  • hypervelocity stars have puzzled astronomers for years. But by observing their speed and direction, astronomers can trace these stars backward, finding that some began moving quickly in the Galactic Center
  • Here, an interaction with the supermassive black hole can kick a star away at an alarming speed
  • Another option is that a supernova explosion propelled a nearby star to a huge speed
  • think M87 might have two supermassive black holes at its center
  • The star cluster wandered too close to the pair, which picked off many of the cluster’s outer stars while the inner core remained intact
  • The black holes then acted like a slingshot, flinging the cluster away at a tremendous speed
Mars Base

Astronomers answer key question: How common are habitable planets? - 0 views

phys.org/...-common-habitable-planets.html

scibyte109

shared by Mars Base on 07 Nov 13 - No Cached
  • astronomers analyzed all four years of Kepler data in search of Earth-size planets in the habitable zones of sun-like stars
  • Based on this analysis, they estimate that 22 percent of stars like the sun have potentially habitable Earth-size planets, though not all may be rocky or have liquid water
  • NASA's Kepler spacecraft
  • ...22 more annotations...
  • provided enough data to complete its mission objective: to determine how many of the 100 billion stars in our galaxy have potentially habitable planets
  • Based on a statistical analysis
  • astronomers now estimate that one in five stars like the sun have planets about the size of Earth and a surface temperature conducive to life.
  • nearly 20 years since the discovery of the first extrasolar planet around a normal star
  • Since then we have learned that most stars have planets of some size and that Earth-size planets are relatively common in close-in orbits that are too hot for life
  • Earth-size planets in Earth-size orbits are not necessarily hospitable to life, even if they orbit in the habitable zone of a star where the temperature is not too hot and not too cold
  • thick atmospheres, making it so hot at the surface that DNA-like molecules would not survive
  • rocky surfaces that could harbor liquid water suitable for living organisms
  • Last week,
  • provided hope that many such planets actually are rocky
  • NASA launched the Kepler space telescope in 2009 to look for planets that cross in front of, or transit, their stars, which causes a slight diminution – about one hundredth of one percent – in the star's brightness
  • 150,000 stars photographed every 30 minutes for four years
  • reported more than 3,000 planet candidates
  • the Keck Telescopes in Hawaii
  • help them determine each star's true brightness and calculate the diameter of each transiting planet, with an emphasis on Earth-diameter planets.
  • The team's definition of habitable is that a planet receives between four times and one-quarter the amount of light that Earth receives from the sun
  • Independently
  • focused on the 42,000 stars that are like the sun or slightly cooler and smaller, and found 603 candidate planets orbiting them
  • Only 10 of these were Earth-size, that is, one to two times the diameter of Earth and orbiting their star at a distance where they are heated to lukewarm temperatures suitable for life
  • Accounting for missed planets, as well as the fact that only a small fraction of planets are oriented so that they cross in front of their host star as seen from Earth, allowed them to estimate that 22 percent of all sun-like stars in the galaxy have Earth-size planets in their habitable zones.
  • All of the potentially habitable planets found in their survey are around K stars, which are cooler and slightly smaller than the sun
  • analysis shows that the result for K stars can be extrapolated to G stars like the sun
Mars Base

Astronomers Identify the Largest Yellow "Hypergiant" Star Known - 0 views

www.universetoday.com/...t-yellow-hypergiant-star-known

scibyte124 star

shared by Mars Base on 13 Mar 14 - No Cached
  • A recent analysis of a star in the south hemisphere constellation of Centaurus has highlighted the role that amateurs play in assisting with professional discoveries in astronomy.
  • The stats for
  • the binary system weighs in at a combined 39 solar masses, has a radius of over 1,300 times that of our Sun, and is a million times as luminous
  • ...15 more annotations...
  • Located 3,600 parsecs or over 11,700 light years distant, the star is 50% larger than the famous red giant Betelgeuse
  • down into the center of our own solar system, and it would extend out over 6 astronomical units (A.U.s) past the orbit of Jupiter
  • also has a relatively small companion star orbiting across our line of sight once every 1300 days
  • The companion star
  • is also a large star in its own right at around six solar masses and 400 solar radii in size.
  • the surface-to-surface distance for the A and B components of the system are “only” about 2.8 A.U.s apart
  • This all means that these two massive stars are in physical contact, with the expanded outer atmosphere of the bloated primary contacting the secondary, giving the pair a distorted peanut shape.
  • yellow hypergiants are some of the brightest stars known
  • That’s just 16x times fainter than the apparent visual magnitude of a Full Moon but over 100 times brighter than Venus
  • if you placed a star like HR 5171 A 32 light years from the Earth, it would easily cast a shadow.
  • the discovery of a companion around such a bright star was a big surprise since any ‘normal’ star should at least be 10,000 times fainter than the hypergiant
  • the hypergiant was much bigger than expected
  • What we see is not the companion itself, but the regions gravitationally controlled and filled by the wind from the hypergiant
  • These latest measurements place HR 5171 A firmly in the “Top 10” for largest stars in terms of size known, as well as the largest yellow hypergiant star known
  • Only eight yellow hypergiants have been identified in our Milky Way galaxy
Mars Base

Smallest Exoplanet Yet Discovered by 'Listening' to a Sun-like Star - 0 views

www.universetoday.com/...y-listening-to-a-sun-like-star

scibyte83 exoplanet

shared by Mars Base on 21 Feb 13 - No Cached
  • Scientists have discovered a new planet orbiting a Sun-like star, and the exoplanet is the smallest yet found in data from the Kepler mission
  • Kepler-37b, is smaller than Mercury, but slightly larger than Earth’s Moon
  • discovery came from a collaboration between Kepler scientists and a consortium of international researchers who employ asteroseismology
  • ...24 more annotations...
  • measuring oscillations in the star’s brightness caused by continuous star-quakes, and turning those tiny variations in the star’s light into sounds
  • The bigger the star, the lower the frequency, or ‘pitch’ of its song
  • The measurements made by the astroseismologists allowed the Kepler research team to more accurately measure the tiny Kepler-37b
  • revealing two other planets in the same planetary system: one slightly smaller than Earth and one twice as large
  • Kepler-37b is very likely a rocky planet with no atmosphere or water, similar to Mercury
  • “The detection of such a small planet shows for the first time that stellar systems host planets much smaller as well as much larger than anything we see in our own Solar System.”
  • host star, Kepler-37, is about 210 light-years from Earth
  • All three planets orbit the star at less than the distance Mercury is to the Sun
  • Kepler-37b orbits every 13 days at less than one-third Mercury’s distance from the Sun
  • estimated surface temperature of this smoldering planet, at more than 800 degrees Fahrenheit (700 degrees Kelvin
  • hot enough to melt the zinc in a penny
  • Kepler-37c and Kepler-37d, orbit every 21 days and 40 days, respectively
  • The size of the star must be known in order to measure the planet’s size accurately
  • scientists examined sound waves generated by the boiling motion beneath the surface of the star
  • The technique for stellar seismology is analogous to how geologists use seismic waves generated by earthquakes to probe the interior structure of Earth
  • sound waves travel into the star and bring information back up to the surface
  • waves cause oscillations that Kepler observes as a rapid flickering of the star’s brightness
  • barely discernible, high-frequency oscillations in the brightness of small stars are the most difficult to measure
  • why most objects previously subjected to asteroseismic analysis are larger than the Sun
  • Kepler-37 has a radius just three-quarters of the Sun
  • the radius of the star is known to 3 percent accuracy, which translates to exceptional accuracy in the planet’s size.
  • this discovery took a long time to verify, as the signature of this very small exoplanet was hard to confirm
  • Kepler is sending astronomers photometry data that’s “probably the best we’ll see in our lifetimes
  • uncovered a planet smaller than any in our solar system orbiting one of the few stars that is both bright and quiet, where signal detection was possible
Mars Base

Kepler finds first multi-planet system around a binary star - 0 views

phys.org/...-multi-planet-binary-star.html

scibyte61 exoplanets

shared by Mars Base on 29 Aug 12 - No Cached
  • NASA's Kepler mission has found the first multi-planet solar system orbiting a binary star
  • proves that whole planetary systems can form in a disk around a binary star
  • binary star in question is called Kepler-47
  • ...9 more annotations...
  • primary star is about the same mass as the Sun, and its companion is an M-dwarf star one-third its size
  • inner planet is three times the size of Earth and orbits the binary star every 49.5 days
  • outer planet is 4.6 times the size of Earth with an orbit of 303.2 days.
  • outer planet is the first planet found to orbit a binary star within the "habitable zone,"
  • the planet's size (about the same as Uranus) means that it is an icy giant, and not an abode for life
  • "The challenging thing is that this is a very faint star," Endl said, "about 6,000 times dimmer than can be seen with the naked eye."
  • The secondary star is too faint to measure
  • taking spectra of the system
  • These values, along with the Kepler eclipse and transit timings, were plugged into a model that calculated the relative sizes of all the bodies involved
Mars Base

Supernova Candidate Stars May Signal "Impending Doom" - 0 views

www.universetoday.com/...tars-may-signal-impending-doom

scibyte24

shared by Mars Base on 02 Dec 11 - No Cached
  • very visible supernova event. Hosted in the Whirlpool Galaxy (M51),
  • researchers at Ohio State University, a galaxy survey may have captured evidence of a “stellar signal” just before it went supernova
  • OSU team was undertaking a survey of 25 galaxies for stars that changed their magnitude in usual ways
  • ...12 more annotations...
  • goal was to find a star just before it ended its life
  • a binary star system located in M51 produced just the results they were looking fo
  • ne star dropped amplitude just a short period of time before the other exploded
  • Maybe stars give off a clear signal of impending doom, maybe they don’t
  • But we’ll learn something new about dying stars no matter the outcome
  • it was a binary star system being studied by the OSU team
  • consisted of both a blue and red star
  • At this point, the astronomers surmise the red star was the one that dimmed significantly over the three-year period while the blue one blew its top
  • reviewing the LBT data
  • when compared with Hubble images, the red star dimmed at about 10% over the final three-year period at an estimated 3% per previous years
  • researchers surmise the red star may have actually survived the supernova event
  • After the light from the explosion fades away, we should be able to see the companion that did not explode
Mars Base

Two 'Weird' Alien Planets Found Around Bright, Distant Stars | Space.com - 1 views

www.space.com/ets-kelt-telescope-aas220.html

scibyte52 exoplanets

shared by Mars Base on 19 Jun 12 - No Cached
  • Astronomers using a small ground-based telescope have discovered two unusual alien planets around extremely bright, distant stars.
  • detected using the Kilodegree Extremely Little Telescope (KELT) in southern Arizona, which has a lens that is roughly as powerful as a high-end digital camera
  • slightly more diminutive than Kepler
  • ...20 more annotations...
  • KELT-1b, is a massive world that is both incredibly hot and dense. The alien planet, which is mostly metallic hydrogen, is slightly larger than Jupiter, but contains a whopping 27 times the mass
  • completes one orbit in a mere 29 hours
  • surface temperature is likely above 4,000 degrees Fahrenheit (roughly 2,200 degrees Celsius
  • receiving 6,000 times the amount of radiation that Earth receives from the sun
  • located approximately 825 light-years away in the constellation of Andromeda
  • massive enough that KELT-1 has raised tides on its parent star and actually spun it
  • both KELT-1 and its parent star are locked in each other's gaze as they go around."
  • KELT-2Ab, and is located about 360 light-years away in the constellation of Auriga
  • 30 percent larger than Jupiter with 50 percent more mass.
  • KELT-2Ab's parent star is so bright it can be seen from Earth through binoculars
  • the star is so luminous that researchers will be able to make direct observations of the planet's atmosphere by examining light that shines through it when the star passes within KELT North's field of view again in November.
  • Follow-up observations are also being planned
  • as well as several space observatories, including the Hubble Space Telescope and the infrared Spitzer Space Telescope.
  • orbits a star that is slightly bigger than the sun, within a binary system
  • one star is slightly bigger than our sun, and the other star is slightly smaller. KELT-2Ab orbits the bigger star, which is bright enough to be seen from Earth with binoculars
  • using the so-called transit method, which involves watching for tiny dips in the star's light that could indicate a planet is crossing, or transiting
  • Rather than staring at a small group of stars at high resolution, the twin KELT North and KELT South telescopes observe millions of very bright stars at low resolution,
  • KELT North scans the northern sky from Arizona
  • KELT South covers the southern sky from Cape Town, South Africa.
  • small ground-based KELT telescopes provide a low-cost alternative for exoplanet hunters by primarily using off-the-shelf technology. The hardware for a KELT telescope costs less than $75,000
Mars Base

2013 in science - Wikipedia, the free encyclopedia - 0 views

en.wikipedia.org/...2013_in_science

scibyte114 2013YearInReview

shared by Mars Base on 23 Dec 13 - No Cached
  • Morocco in 2011, and report that it is a new type of Mars rock with an unusually high water content.[8][9][10] American researchers state that a gene associated with active personality traits is also linked to
  • Astronomers affiliated with the Kepler space observatory announce the discovery of KOI-172.02, an Earth-like exoplanet candidate which orbits a star similar to the Sun in the habitable zone
  • 13 January – Massachusetts doctors invent a pill-sized medical scanner that can be safely swallowed by patients, allowing the esophagus to be more easily scanned for disease
  • ...101 more annotations...
  • 17 January – NASA announces that the Kepler space observatory has developed a reaction wheel issue
  • 2 January A study by Caltech astronomers reports that the Milky Way Galaxy contains at least one planet per sta
  • 3 January
  • 8 January
  • 20 January – Scientists prove that quadruple-helix DNA is present in human cells
  • 25 January
  • An international team of scientists develops a functional light-based "tractor beam", which allows individual cells to be selected and moved at will. The invention could have broad applications in medicine and microbiology
  • 30 January – South Korea conducts its first successful orbital launch
  • 6 February
  • Astronomers report that 6% of all dwarf stars – the most common stars in the known universe – may host Earthlike planets
  • Scientists discover live bacteria in the subglacial Antarctic Lake Whillans
  • American scientists finish drilling down to the subglacial Lake Whillans, which is buried around 1 kilometre (0.62 mi) under the Antarctic ice
  • 10 February NASA's Curiosity Mars rover uses its onboard drill to obtain the first deep rock sample ever retrieved from the surface of another plane
  • 15 February A 10-ton meteoroid impacts in Chelyabinsk, Russia, producing a powerful shockwave and injuring over 1,000 people
  • 28 February
  • Astronomers make the first direct observation of a protoplanet forming in a disk of gas and dust around a distant sta
  • A third radiation belt is discovered around the Eart
  • 1 March – Boston Dynamics demonstrates an updated version of its BigDog military robot
  • 3 March – American scientists report that they have cured HIV in an infant by giving the child a course of antiretroviral drugs very early in its life. The previously HIV-positive child has reportedly exhibited no HIV symptoms since its treatment, despite having no further medication for a year
  • researchers replace 75 percent of an injured patient's skull with a precision 3D-printed polymer replacement implant. In future, damaged bones may routinely be replaced with custom-manufactured implants
  • 7 March
  • A study concludes that heart disease was common among ancient mummies
  • 11 March
  • 12 March NASA's Curiosity rover finds evidence that conditions on Mars were once suitable for microbial life after analyzing the first drilled sample of Martian rock, "John Klein" rock at Yellowknife Bay in Gale Crater. The rover detected water, carbon dioxide, oxygen, sulfur dioxide, hydrogen sulfide, chloromethane and dichloromethane. Related tests found results consistent with the presence of smectite clay minerals
  • 14 March CERN scientists confirm, with a very high degree of certainty, that a new particle identified by the Large Hadron Collider in July 2012 is the long-sought Higgs boson
  • 18 March
  • NASA reports evidence from the Curiosity rover on Mars of mineral hydration, likely hydrated calcium sulfate, in several rock samples, including the broken fragments of "Tintina" rock and "Sutton Inlier" rock as well as in the veins and nodules in other rocks like "Knorr" rock and "Wernicke" rock.[177] Analysis using the rover's DAN instrument provided evidence of subsurface water, amounting to as much as 4% water content, down to a depth of 60 cm
  • 27 March – A potential new weight loss method is discovered, after a 20% weight reduction was achieved in mice simply by having their gut microbes altered.
  • NASA scientists report that hints of dark matter may have been detected by the Alpha Magnetic Spectrometer on the International Space Station
  • 3 April
  • 15 April A functional lab-grown kidney is successfully transplanted into a live rat in Massachusetts General Hospital
  • 18 April – NASA announces the discovery of three new Earthlike exoplanets – Kepler-62e, Kepler-62f, and Kepler-69c – in the habitable zones of their respective host stars, Kepler-62 and Kepler-69. The new exoplanets, which are considered prime candidates for possessing liquid water and thus potentially life, were identified using the Kepler spacecraft
  • 21 April The Antares rocket, a commercial launch vehicle developed by Orbital Sciences Corporation, successfully conducts its maiden flight
  • After years of unpowered glide tests, Scaled Composites' SpaceShipTwo hybrid spaceplane successfully conducts its first rocket-powered fligh
  • 29 April
  • 1 May IBM scientists release A Boy and His Atom, the smallest stop-motion animation ever created, made by manipulating individual carbon monoxide molecules with a scanning tunnelling microscope
  • A new study finds that children whose parents suck on their pacifiers have fewer allergies later in life
  • NASA reports that a reaction wheel on the Kepler space observatory may be malfunctioning and may result in the premature termination of the observatory's search for Earth-like
  • 15 May
  • 16 May Water dating back 2.6 billion years, by far the oldest ever found, is discovered in a Canadian mine
  • 27 May Four-hundred-year-old bryophyte specimens left behind by retreating glaciers in Canada are brought back to life in the laboratory
  • 29 May
  • Russian scientists announce the discovery of mammoth blood and well-preserved muscle tissue from an adult female specimen in Siberia
  • A new treatment to "reset" the immune system of multiple sclerosis patients is reported to reduce their reactivity to myelin by 50 to 75 percent
  • 4 June
  • During the Shenzhou 10 mission, Chinese astronauts deliver the country's first public video broadcast from the orbiting Tiangong-1 space laboratory
  • 20 June
  • China's Shenzhou 10 manned spacecraft returns safely to Earth, having conducted China's longest manned space mission to date
  • 26 June
  • 20 June
  • 20 June
  • 6 July
  • Scientists report that a wide variety of microbial life exists in the subglacial Antarctic Lake Vostok, which has been buried in ice for around 15 million years. Samples of the lake's water obtained by drilling were found to contain traces of DNA from over 3,000 tiny organisms
  • 15 July
  • ASA engineers successfully test a rocket engine with a fully 3D-printed injector
  • 19 July
  • NASA scientists publish the results of a new analysis of the atmosphere of Mars, reporting a lack of methane around the landing site of the Curiosity rover
  • Earth is photographed from the outer solar system. NASA's Cassini spacecraft releases images of the Earth and Moon taken from the orbit of Saturn
  • 29 July – Astronomers discover the first exoplanet orbiting a brown dwarf, 6,000 light years from Earth
  • exoplanet
  • 7 January
  • Astronomers
  • report that "at least 17 billion" Earth-sized exoplanets are estimated to reside in the Milky Way Galaxy
  • 20 February
  • NASA reports the discovery of Kepler-37b, the smallest exoplanet yet known, around the size of Earth's Moon
  • 10 June
  • Scientists report that the earlier claims of an Earth-like exoplanet orbiting Alpha Centauri B, a star close to our Solar System, may not be supported by astronomical evidence
  • 25 June – In an unprecedented discovery, astronomers detect three potentially Earthlike exoplanets orbiting a single star in the Gliese 667
  • 11 July For the first time, astronomers determine the true colour of a distant exoplanet. HD 189733 b, a searing-hot gas giant, is said to be a vivid blue colour, most likely due to clouds of silica in its atmosphere
  • NASA announces that the failing Kepler space observatory may never fully recover. New missions are being considered
  • 15 August
  • Phase I clinical trials of SAV001 – the first and only preventative HIV vaccine – have been successfully completed with no adverse effects in all patients. Antibody production was greatly boosted after vaccination
  • 3 September
  • 12 September NASA announces that Voyager I has officially left the Solar System, having travelled since 1977
  • NASA scientists report the Mars Curiosity rover detected "abundant, easily accessible" water (1.5 to 3 weight percent) in soil samples
  • 26 September
  • In addition, the rover found two principal soil types: a fine-grained mafic type and a locally derived, coarse-grained felsic type
  • mafic
  • as associated with hydration of the amorphous phases of the soi
  • perchlorates, the presence of which may make detection of life-related organic molecules difficult, were found at the Curiosity rover landing site
  • earlier at the more polar site of the Phoenix lander) suggesting a "global distribution of these salts
  • Astronomers have created the first cloud map of an exoplanet, Kepler-7b
  • 30 September
  • 8 October The Nobel Prize in Physics has been awarded to François Englert and Peter Higgs "for the theoretical discovery of a mechanism that contributes to our understanding of the origin of mass of subatomic particles, and which recently was confirmed through the discovery of the predicted fundamental particle, by the ATLAS and CMS experiments at CERN's Large Hadron Collider"
  • 16 October Russian authorities raise a large fragment, 654 kg (1,440 lb) total weight, of the Chelyabinsk meteor, a Near-Earth asteroid that entered Earth's atmosphere over Russia on 15 February 2013, from the bottom of Chebarkul lake.
  • Researchers have shown that a fundamental reason for sleep is to clean the brain of toxins. This is achieved by brain cells shrinking to create gaps between neurons, allowing fluid to wash through
  • 17 October
  • 22 October – Astronomers have discovered the 1,000th known exoplanet
  • 4 November - Astronomers report, based on Kepler space mission data, that there could be as many as 40 billion Earth-sized planets orbiting in the habitable zones of sun-like stars and red dwarf stars within the Milky Way Galaxy
  • 11 billion of these estimated planets may be orbiting sun-like stars
  • 5 November – India launches its first Mars probe, Mangalyaan
  • The IceCube Neutrino Observatory has made the first discovery of very high energy neutrinos on Earth which had originated from beyond our Solar System
  • 21 November
  • 1 December – China launches the Chang'e 3 lunar rover mission, with a planned landing on December 16
  • 3 December – The Hubble Space Telescope has found evidence of water in the atmospheres of five distant exoplanets: HD 209458b, XO-1b, WASP-12b, WASP-17b and WASP-19b
  • 9 December NASA scientists report that the planet Mars had a large freshwater lake (which could have been a hospitable environment for microbial life) based on evidence from the Curiosity rover studying Aeolis Palus near Mount Sharp in Gale Crater
  • 12 December NASA announces, based on studies with the Hubble Space Telescope, that water vapor plumes were detected on Europa, moon of Jupiter
  • 14 December – The unmanned Chinese lunar rover Chang'e 3 lands on the Moon, making China the third country to achieve a soft landing there
  • 18 December
  • nomers have spotted what appears to be the first known "exomoon", located 1,800 light years away
  • 20 December – NASA reports that the Curiosity rover has successfully upgraded, for the third time since landing, its software programs and is now operating with version 11. The new software is expected to provide the rover with better robotic arm and autonomous driving abilities. Due to wheel wear, a need to drive more carefully, over the rough terrain the rover is currently traveling on its way to Mount Sharp, was also reported
Mars Base

Faraway moon or faint star? Possible exomoon found - 0 views

phys.org/...y-moon-faint-star-exomoon.html

scibyte126 exoplanets

shared by Mars Base on 11 Apr 14 - No Cached
  • NASA-funded researchers have spotted the first signs of an "exomoon," and though they say it's impossible to confirm its presence
  • The discovery was made by watching a chance encounter of objects in our galaxy, which can be witnessed only once
  • won't have a chance to observe the exomoon candidate again
  • ...29 more annotations...
  • can expect more unexpected finds like this.
  • international study
  • using telescopes
  • technique, called gravitational microlensing, takes advantage of chance alignments between stars
  • When a foreground star passes between us and a more distant star, the closer star can act like a magnifying glass to focus and brighten the light of the more distant one
  • These brightening events usually last about a month
  • If the foreground star—or what astronomers refer to as the lens—has a planet circling around it, the planet will act as a second lens to brighten or dim the light even more
  • carefully scrutinizing these brightening events, astronomers can figure out the mass of the foreground star relative to its planet.
  • the foreground object could be a free-floating planet, not a star
  • astronomers are actively looking for exomoons—for example, using data from NASA's Kepler mission - so far, they have not found any.
  • In the new study, the nature of the foreground, lensing object is not clear. The ratio of the larger body to its smaller companion is 2,000 to 1.
  • That means the pair could be either a small, faint star circled by a planet about 18 times the mass of Earth—or a planet more massive than Jupiter coupled with a moon weighing less than Earth.
  • astronomers have no way of telling which of these two scenarios is correct
  • One possibility is for the lensing system to be a planet and its moon
  • The answer to the mystery lies in learning the distance to the circling duo
  • A lower-mass pair closer to Earth will produce the same kind of brightening event as a more massive pair located farther away
  • once a brightening event is over, it's very difficult to take additional measurements of the lensing system and determine the distance
  • The true identity of the exomoon candidate and its companion, a system dubbed MOA-2011-BLG-262, will remain unknown
  • In the future, however, it may be possible to obtain these distance measurements during lensing events
  • NASA's Spitzer and Kepler space telescopes, both of which revolve around the sun in Earth-trailing orbits, are far enough away from Earth to be great tools for the parallax-distance technique.
  • The basic principle of parallax can be explained by holding your finger out, closing one eye after the other, and watching your finger jump back and forth
  • A distant star, when viewed from two telescopes spaced really far apart, will also appear to move
  • When combined with a lensing event, the parallax effect alters how a telescope will view the resulting magnification of starlight
  • Though the technique works best using one telescope on Earth and one in space, such as Spitzer or Kepler, two ground-based telescopes on different sides of our planet can also be used
  • Meanwhile, surveys
  • are turning up more and more planets
  • These microlensing surveys have discovered dozens of exoplanets so far, in orbit around stars and free-floating
  • A previous NASA-funded study, also led by the MOA team, was the first to find strong evidence for planets the size of Jupiter roaming alone in space, presumably after they were kicked out of forming planetary systems
  • The new exomoon candidate, if real, would orbit one such free-floating planet.
Mars Base

First potentially habitable Earth-sized planet confirmed: It may have liquid water - 0 views

phys.org/...earth-sized-planet-liquid.html

scibyte127 exoplanet

shared by Mars Base on 19 Apr 14 - No Cached
  • The first Earth-sized exoplanet orbiting within the habitable zone of another star has been confirmed by observations with both the W. M. Keck Observatory and the Gemini Observatory
  • The initial discovery, made by NASA's Kepler Space Telescope, is one of a handful of smaller planets found by Kepler and verified using large ground-based telescopes
  • his Earth-sized planet, one of five orbiting this star, which is cooler than the Sun, resides in a temperate region where water could exist in liquid form
  • ...12 more annotations...
  • neither Kepler (nor any telescope) is currently able to directly spot an exoplanet of this size and proximity to its host star
  • can do is eliminate essentially all other possibilities so that the validity of these planets is really the only viable option
  • With such a small host star, the team employed a technique that eliminated the possibility that either a background star or a stellar companion could be mimicking what Kepler detected
  • the team obtained extremely high spatial resolution observations from the eight-meter Gemini North telescope on Mauna Kea in Hawai
  • using a technique called speckle imaging, as well as adaptive optics (AO) observations from the ten-meter Keck II telescope
  • The Gemini "speckle" data directly imaged the system to within about 400 million miles (about 4 AU, approximately equal to the orbit of Jupiter in our solar system) of the host star and confirmed that there were no other stellar size objects orbiting within this radius from the star
  • The host star, Kepler-186, is an M1-type dwarf star relatively close to our solar system, at about 500 light years and is in the constellation of Cygnus
  • The star is very dim, being over half a million times fainter than the faintest stars we can see with the naked eye
  • Five small planets have been found orbiting this star, four of which are in very short-period orbits and are very hot
  • Differential Speckle Survey Instrument (DSSI) on the Gemini North telescope
  • is a visiting instrument
  • works on a principle that utilizes multiple short exposures of an object to capture and remove the noise introduced by atmospheric turbulence producing images with extreme detail
Mars Base

A planetary system from the early Universe - 0 views

www.physorg.com/...-planetary-early-universe.html

scibyte40 exoplanet

shared by Mars Base on 28 Mar 12 - No Cached
  • A group of European astronomers has discovered an ancient planetary system that is likely to be a survivor from one of the earliest cosmic eras, 13 billion years ago. The system consists of the star HIP 11952 and two planets, which have orbital periods of 290 and 7 days, respectively. Whereas planets usually form within clouds that include heavier chemical elements, the star HIP 11952 contains very little other than hydrogen and helium. The system promises to shed light on planet formation in the early universe – under conditions quite different from those of later planetary systems, such as our own
  • widely accepted that planets are formed in disks of gas and dust that swirl around young stars
  • many open questions remain
  • ...25 more annotations...
  • what it actually takes to make a planet
  • With a sample of, by now, more than 750 confirmed planets
  • astronomers have some idea of the diversity among planetary systems
  • certain trends have emerged
  • Statistically, a star that contains more “metals” - in astronomical parlance, the term includes all chemical elements other than hydrogen and helium – is more likely to have planets.
  • suggests a key question
  • Originally, the universe contained almost no chemical elements other than hydrogen and helium
  • what about planet formation under conditions like those of the very early universe
  • ? If metal-rich stars are more likely to form planets
  • stars with a metal content so low that they cannot form planets at all
  • then when
  • should we expect the very first planets to form
  • a group of astronomers
  • has discovered a planetary system that could help provide answers to those questions
  • part of a survey targeting especially metal-poor stars
  • identified two giant planets around a star known by its catalogue number as HIP 11952
  • at a distance of about 375 light-years from Earth
  • these planets
  • are not unusual
  • What is unusual is the fact that they orbit such an extremely metal-poor and, in particular, such a very old star!
  • planets around such a star should be extremely rare
  • Compared to other exoplanetary systems
  • not only one that is extremely metal-poor
  • at an estimated age of 12.8 billion years, also one of the oldest systems known so far.
  • In 2010 we found the first example of such a metal-poor system, HIP 13044. Back then, we thought it might be a unique case; now, it seems as if there might be more planets around metal-poor stars than expected
Mars Base

Nearby Ancient Star is Almost as Old as the Universe - 0 views

www.universetoday.com/...-almost-as-old-as-the-universe

scibyte84

shared by Mars Base on 24 Feb 13 - No Cached
  • A metal-poor star located merely 190 light-years from the Sun is 14.46+-0.80 billion years old, which implies that the star is nearly as old as the Universe
  • results emerged from a new study
  • Such metal-poor stars are (super) important to astronomers because they set an independent lower limit for the age of the Universe
  • ...21 more annotations...
  • can be used to corroborate age estimates inferred by other means
  • In the past, analyses of globular clusters and the Hubble constant
  • yielded vastly different ages for the Universe, and were offset by billions of years
  • based on the microwave background and Hubble constant, but it must have formed soon after the big bang
  • Within the errors, the age of HD 140283 does not conflict with the age of the Universe, 13.77 ± 0.06 billion years
  • Metal-poor stars can be used to constrain the age of the Universe because metal-content is typically a proxy for age
  • Heavier metals are generally formed in supernova explosions, which pollute the surrounding interstellar medium.
  • Stars subsequently born from that medium are more enriched with metals than their predecessors
  • each successive generation becoming increasingly enriched
  • HD 140283 exhibits less than 1% the iron content of the Sun, which provides an indication of its sizable age.
  • had been used previously to constrain the age of the Universe, but uncertainties tied to its estimated distance (at that time) made the age determination somewhat imprecise
  • obtain a new and improved distance for HD 140283 using the Hubble Space Telescope (HST), namely via the trigonometric parallax approach
  • distance uncertainty for HD 140283 was significantly reduced by comparison to existing estimates, thus resulting in a more precise age estimate for the star
  • The reliability of the age determined is likewise contingent on accurately determining the sample’s metal content
  • analyses of globular clusters and the Hubble constant yielded vastly different ages for the Universe
  • discrepant ages stemmed partly from uncertainties in the cosmic distance scale
  • determination of the Hubble constant relied on establishing (accurate) distances to galaxies
  • One of the key objectives envisioned for HST was to reduce uncertainties associated with the Hubble constant to <10%, thus providing an improved estimate for the age of the Universe
  • the mean implying an age near ~14 billion years
  • Determining a reliable age for stars in globular clusters is likewise contingent on the availability of a reliable distance
  • the study reaffirms that there are old stars roaming the solar neighborhood which can be used to constrain the age of the Universe
Mars Base

Ancient Quasar Shines Brightly, But All the Galaxy's Stars Are Missing - 0 views

www.universetoday.com/...-the-galaxys-stars-are-missing

scibyte69 quasar

shared by Mars Base on 24 Oct 12 - No Cached
  • Quasars have been the best and most easily observed beacons for astronomers to probe the distant Universe
  • one of the most distant and brightest quasars is providing a bit of a surprise
  • Astronomers studying a distant galaxy, dubbed J1148+5251 and which contains a bright quasar, are seeing only the quasar and not the host galaxy itself
  • ...15 more annotations...
  • has been thought that the quasar has been feeding on a handful of stars every year in order to bulk up to its size of three billion solar masses over just a few hundred million years. But where are all the stars
  • Near infrared views with the Hubble Space Telescope’s Wide Field Camera 3 are only providing hints of what might be taking place
  • galaxy is so enshrouded with dust that none of the starlight can be seen
  • only the bright, blaring quasar shines through
  • most early galaxies contain hardly any dust
  • the early universe was dust-free until the first generation of stars started making dust through nuclear fusion
  • quasar was first identified in the Sloan Digital Sky Survey (SDSS) and the follow-up submillimeter observations showed significant dust but not how and where
  • If you want to hide the stars with dust
  • make lots of short-lived massive stars earlier on that lose their mass at the end of their lifetime
  • used Hubble to very carefully subtract light from the quasar image and look for the glow of surrounding stars.
  • remarkable
  • Hubble didn’t find any of the underlying galaxy
  • Because we don’t see the stars, we can rule out that the galaxy that hosts this quasar is a normal galaxy
  • It’s among the dustiest galaxies in the universe
  • so widely distributed that not even a single clump of stars is peeking through
Mars Base

Billions of Habitable Worlds Likely in the Milky Way - 0 views

www.universetoday.com/...worlds-likely-in-the-milky-way

scibyte40 exoplanet

shared by Mars Base on 28 Mar 12 - No Cached
  • results from a new study that searched for rocky planets in the habitable zones around red dwarf stars
  • now estimates that there are tens of billions of such planets in the Milky Way galaxy
  • probably about one hundred in the Sun’s immediate neighborhood, less than 30 light years away.
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  • new observations with HARPS mean that about 40% of all red dwarf stars have a super-Earth orbiting in the habitable zone where liquid water can exist on the surface of the planet
  • first direct estimate of the number of smaller, rocky planets around red dwarf stars
  • another recent finding which suggested that every star in our night sky has at least one planet circling it — which didn’t include red dwarf stars – and our galaxy could be teeming with worlds
  • HARPS team surveyed a carefully chosen sample of 102 red dwarf stars in the southern skies over a six-year period
  • total of nine super-Earths (planets with masses between one and ten times that of Earth) were found, including two inside the habitable zones of Gliese 581 and Gliese 667 C respectively
  • combining all the data, including observations of stars that did not have planets, and looking at the fraction of existing planets that could be discovered, the team has been able to work out how common different sorts of planets are around red dwarfs
  • find that the frequency of occurrence of super-Earths in the habitable zone is 41% with a range from 28% to 95%.
  • Less than 12% of red dwarfs are expected to have giant planets (with masses between 100 and 1000 times that of the Earth).
  • habitable zone around a red dwarf, where the temperature is suitable for liquid water to exist on the surface, is much closer to the star than the Earth is to the Sun
  • But red dwarfs are known to be subject to stellar eruptions or flares, which may bathe the planet in X-rays or ultraviolet radiation, and which may make life there less likely.”
  • Gliese 667 Cc. This is the second planet in this triple star system and seems to be situated close to the center of the habitable zone
  • this planet is more than four times heavier than the Earth it is the closest twin to Earth found so far and almost certainly has the right conditions for the existence of liquid water on its surface
  • second super-Earth planet inside the habitable zone of a red dwarf
Mars Base

Direct Image of an Exoplanet 155 Light Years Away - 0 views

www.universetoday.com/...exoplanet-155-light-years-away

scibyte131 exoplanet

shared by Mars Base on 15 May 14 - No Cached
  • This week, an international team of researchers
  • announced the discovery of an exoplanet
  • 155 light years
  • ...20 more annotations...
  • world is estimated to be 11 times the mass of Jupiter — placing it just under the lower mass limit for brown dwarf status
  • orbits its host star 2,000x farther than the distance from Earth to the Sun once every 80,000 (!) years
  • The primary star, GU Psc A, is an M3 red dwarf weighing in at 35% the mass of our Sun and is just 100 million years old
  • researchers targeted GU Psc after it was determined to be a member of the AB Doradus moving group of relatively young stars, which are prime candidates for exoplanet detection
  • The fact that GU Psc B was captured by direct imaging at 155 light years distant is amazing
  • The team was able to discern this curious planet by utilizing observations from the W.M. Keck observatory, the joint Canada-France-Hawaii Telescope, the Gemini Observatory and the Observatoire Mont-Mégantic in Québec.
  • there are not a lot of exoplanets that were detected ‘directly’ so far
  • The few planets for which we have an actual image are interesting because we can analyze their light directly, and thus learn much more about them
  • researcher Marie-Ève Naud and her co-advisor Étienne Artigau
  • also one of the “coolest” planets that have been directly imaged, showing methane absorption
  • it is certainly the most distant exoplanet to a main-sequence star that has been found so far
  • This distance makes GU Psc b very interesting from a theoretical point of view, because it’s hard to imagine how it could have formed in the protoplanetary disk of its star
  • current working definition of an exoplanet is based solely on mass (<13 Jupiter masses), so GU Psc b probably formed in a way that is more similar to how stars formed
  • how are astronomers certain that PU Psc b is related to its host and not a foreground or background object?
  • As the host star, GU Psc is relatively nearby; it displays a significant apparent proper motion
  • relative to distant background stars and galaxies.
  • On images taken one year apart with WIRCam on the Canada-France-Hawaii Telescope, we observed that the companion displays the same big proper motion, i.e. they move together in the plane of the sky, while the rest of the stars in the field don’t
  • most planet hunting techniques using direct imaging involve state-of-the-art adaptive optics systems, but we used ‘standard’ imaging without any exotic techniques
  • To find this planet, we used very sensitive ‘standard’ imaging,
  • we chose carefully the wavelengths where planets display colors that are unlike most other astrophysical objects such as stars and galaxies
Mars Base

Distant planets' atmospheres revealed | Atom & Cosmos | Science News - 0 views

www.sciencenews.org/...t_planets_atmospheres_revealed

scibyte86 exoplanet

shared by Mars Base on 15 Mar 13 - No Cached
  • Astronomers have gotten the most detailed look yet at the atmosphere of a planet outside the solar system
  • The study is among the first to directly analyze the chemical makeup of an exoplanet
  • In the past, astronomers inferred the existence of exoplanets and their gases by looking for subtle changes in the light streaming from the planet’s star
  • ...42 more annotations...
  • Now, with improved instruments, a team
  • has detected light coming directly from a planet light-years away
  • The data have high enough resolution to reveal not only the presence but the abundance of carbon monoxide and water in the planet’s atmosphere
  • Such information could shed light on how the planet formed
  • studies could also reveal the presence of life on a distant planet, but the planet’s size and orbit have already ruled it out as a habitable world
  • In 2008
  • the first image of a multiplanet system outside the solar system, showing three gas giants orbiting the star HR 8799
  • HR 8799 is about 130 light-years from Earth, in the constellation Pegasus
  • The planets are scorching hot, making them bright enough for astronomers to detect directly
  • In 2010, the researchers imaged a fourth planet around HR 8799
  • In the new study
  • focused on one of these planets, HR 8799c.
  • Five to 10 times as massive as Jupiter, HR 8799c sits about eight times farther away from its star than Jupiter does from the sun
  • Because of that great distance, the astronomers could block the star’s light and record infrared light
  • Because different gases absorb and emit light in distinct ways, the team could identify carbon monoxide and water but found no methane, which scientists had thought might be present.
  • In another new study
  • researchers simultaneously collected infrared light from the atmospheres of all four planets
  • A team led by
  • an astrophysicist at the American Museum of Natural History in New York City, found hints of ammonia, methane, carbon dioxide and acetylene in the planets’ atmospheres
  • The chemistry of each planet varies
  • different from anything in our own solar system
  • Although the teams looked at different wavelengths of light, which pick up different types of molecules, the two studies appear consistent
  • by peering at just one planet, Konopacky’s team obtained more detailed data that allowed the researchers to get a sense of how much carbon and oxygen is in HR 8799c’s atmosphere
  • Knowing the ratio of carbon to oxygen in the atmosphere may reveal how the planet formed
  • Astronomers have two competing theories of how planets arise from the disk of gas and dust encircling a young star
  • In the gravitational instability model, some of the gas and dust suddenly clumps and collapses, simultaneously creating a planet’s core and atmosphere
  • In this scenario, the chemical composition of a planet should match that of its star
  • In the other model, known as core accretion, planet building is a two-step process
  • First, material from the disk accumulates into a core.
  • Later, the core captures gases swirling in the disk to form an atmosphere.
  • In this case, the carbon-to-oxygen ratio of the planet may differ from the star because the accretion of cores may deplete the disk of certain elements
  • Compared with its star, HR 8799c appears to have slightly more carbon relative to oxygen, suggesting the planet originated via core accretion
  • surmise that when the disk around HR 8799 formed, water froze into particles of ice.
  • The bits of ice collided to form the planet’s core, leaving behind little water vapor, and therefore less oxygen, when the planet accumulated its atmosphere later on
  • Other researchers are not convinced by this conclusion
  • “We don’t really understand planetary formation enough to make a strong case either way,”
  • the data from both new studies may help astronomers refine their simulations of planetary formation
  • astronomers have directly imaged planets around three distant stars
  • researchers are poised to capture light from many more planets
  • Project 1640,
  • is looking for Jupiter-sized planets around some 200 stars
  • “Ultimately, with better instruments, people will be able to use these methods on Earthlike planets.”
Mars Base

Supermassive Black Hole Swallows Star | Hungry Black Holes | Space.com - 0 views

www.space.com/-black-hole-swallows-star.html

scibyte45 black holes star

shared by Mars Base on 03 May 12 - No Cached
  • star whose death may ultimately provide more clues on the inner workings of the enigmatic gravitational monster that devoured it.
  • In June 2010, the researchers spotted a bright flare from the previously dormant black hole at the center of a galaxy approximately 2.7 billion light-years away.
  • The flare of light reached peak brightness a month after it was detected, then slowly faded over the next 12 months
  • ...12 more annotations...
  • By measuring the rise of the flare's brightness, the scientists calculated the rate at which the star's gas was getting sucked into the black hole
  • helped reveal at what point and time the black hole had begun disrupting the star, revealing how powerful its gravitational field was and thus its mass.
  • estimate the black hole's mass to be 3 million suns
  • like we are gathering evidence from a crime scene
  • analyzed the spectrum of the ejected gas — that is, the specific colors making up its light
  • using data from the Multiple Mirror Telescope Observatory on Mount Hopkins in Arizona
  • and the spectrum of the gas revealed it was mostly helium.
  • unique spectral fingerprint
  • fact there was mostly helium and very little hydrogen in the gas suggests "the slaughtered star had to have been the helium-rich core of a stripped star
  • This likely happened when the star went through the red giant phase, where it expanded to 100 times its original radius
  • it puffed up like that, it became vulnerable to the gravitational tidal forces of the black hole, and it would have been very easy to strip off the tenuous hydrogen envelope
  • the star then had to approach much closer, 100 times closer in, before it was completely disrupted by the black hole
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