Friday, March 25, 2016

The Moon’s Other Axis

The Moon’s Other Axis:



A six degree True Polar Wander occurred on the Moon due to ancient volcanic activity. Image: University of Arizona/James Tuttle Keane


It's tempting to think that the Moon never changes. You can spend your whole life looking at it, and see no evidence of change whatsoever. In fact, the ancients thought the whole Universe was unchanging.You may have heard of a man named Aristotle. He thought the Universe was eternal and unchanging. Obviously, with our knowledge of the Big Bang, stellar evolution, and planetary formation, we know better. Still, the placid and unchanging face of the Moon can tempt us into thinking astronomers are making up all this evolving universe stuff.But now, according to a new paper in Nature, the Moon's axis of rotation is different now than it was billions of years ago. Not only that, but volcanoes may been responsible for it. Volcanoes! On our placid little Moon.The clue to this lunar True Polar Wander (TPW) is in the water ice locked in the shadows of craters on the Moon. When hydrogen was discovered on the surface of the Moon in the 1990s by the Lunar Prospector probe, scientists suspected that they would eventually find water ice. Subsequent missions proved the presence of water ice, especially in craters near the polar regions. But the distribution of that water-ice wasn't uniform.You would expect to see ice uniformly distributed in the shadows of craters in the polar regions, but that's not what scientists have found. Instead, some craters had no evidence of ice at all, which led the team behind this paper to conclude that these ice-free craters must have been exposed to the Sun at some point. What else would explain it?The way that the ice in these craters is distributed forms two trails that lead away from each pole. They're mirror images of each other, but they don't conform with the Moon's current axis of rotation, which is what led the team to conclude that the Moon underwent a 6 degree TPW billions of years ago.The paper also highlights the age of the water on the Moon. Since the TPW, and the melting of some of the ice as a result of it, occurred some billions of years ago, then the water ice that is still frozen in the shadows of some of the Moon's craters must be ancient. According to the paper, its existence records the "early delivery of water to the inner Solar System." Hopefully, a future mission will return a sample of this ancient water for detailed study.But even more interesting than the age of the ice in the craters and the TPW, to me anyways, is what is purported to have caused it. The team behind the paper reports that volcanic activity on the Moon in the Procellarum region, which was most active in the early history of the Moon, moved a substantial amount of material and "altered the density structure of the Moon." This alteration would have changed the moments of inertia on the Moon, resulting in a TPW.It's strange to think of the Moon with volcanic activity viewable from Earth. I wonder what effect visible lunar volcanoes would have had on thinkers like Aristotle, if lunar volcanic activity had occurred during recorded history, rather than ending one billion years ago or so.We know that events like eclipses and comets caused great confusion and sometimes upheaval in ancient civilizations. Would lunar volcanoes have had the same effect?

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Posted by Nelio Inacio at 1:20 PM 0 comments

ExoMars Mission Narrowly Avoids Exploding Booster

ExoMars Mission Narrowly Avoids Exploding Booster:



The ExoMars craft releases the Schiaparelli lander in October in this artist's view. Credit: ESA


On March 14, the ExoMars mission successfully lifted off on a 7-month journey to the planet Mars but not without a little surprise. The Breeze-M upper booster stage, designed to give the craft its final kick toward Mars, exploded shortly after parting from the probe. Thankfully, it wasn't close enough to damage the spacecraft.Michel Denis, ExoMars flight director at the European Space Operations, Center in Darmstadt, Germany, said that the two craft were many kilometers apart at the time of the breakup, so the explosion wouldn't have posed a risk. Still, the mission team won't be 100% certain until all the science instruments are completely checked over in the coming weeks.All went well during the takeoff and final separation of the probe, but then something odd happened. Breeze-M was supposed to separate cleanly into two pieces — the main body and a detachable fuel tank — and maneuver itself to a graveyard or "junk" orbit, where rockets and spacecraft are placed at the end of their useful lives, so they don't cause trouble with operational satellites.But instead of two pieces, tracking photos taken at the OASI Observatory in Brazil not long after the stage and probe separated show  a cloud of debris, suggesting an explosion occurred that shattered the booster to pieces.It wouldn't be the first time a Russian Breeze-M blew up.According to Russian space observer Anatoly Zak in a recent article in Popular Mechanics, a Breeze-M that delivered a Russian spy satellite into orbit last December exploded on January 16. Propellant in one of its fuel tanks may not have been properly vented into space; heated by the sun, the tank's contents likely combusted and ripped the stage apart. A similar incident occurred in October 2012.For now, we'll embrace the good news that the spacecraft, which houses the Trace Gas Orbiter (TGO) and the Schiaparelli lander, are underway to Mars and in good health.ExoMars is a joint venture between the European Space Agency (ESA) and the Russian Federal Space Agency (Roscosmos). One of the mission’s key goals is to follow up on the methane detection made by ESA’s Mars Express probe in 2004 to understand where the gas comes from. Mars' atmosphere is 95% carbon dioxide with the remaining 5% divided among nitrogen, argon, oxygen and others including small amounts of methane, a gas that on Earth is produced largely by living creatures.Scientists want to know how martian methane got into the atmosphere. Was it produced by biology or geology? Methane, unless it is continuously produced by a source, only survives in the Martian atmosphere for a few hundreds of years because it quickly breaks down to form water and carbon dioxide. Something is refilling the atmosphere with methane but what?TGO will also look at potential sources of other trace gases such as volcanoes and map the planet's surface. It can also detect buried water-ice deposits, which, along with locations identified as sources of the trace gases, could influence the choice of landing sites of future missions.The orbiter will also act as a data relay for the second ExoMars mission — a rover and stationary surface science platform scheduled for launch in May 2018 and arriving in early 2019.On October 16, when the spacecraft is still 559,000 miles (900,000 kilometers) from the Red Planet, the Schiaparelli lander will separate from the orbiter and three days later parachute down to the Martian surface. The orbiter will take measurements of the planet's atmosphere (including methane) as well as any atmospheric electrical fields.Mars is a popular place. There are currently five active orbiters there: two European (Mars Express and Mars Odyssey), two American (Mars Reconnaissance Orbiter and MAVEN), one Indian (Mars Orbiter Mission) and two rovers (Opportunity and Curiosity) with another lander and orbiter en route!

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Posted by Nelio Inacio at 1:17 PM 0 comments

A Picturesque Equinox Sunset

A Picturesque Equinox Sunset: APOD: 2016 March 20 - A Picturesque Equinox Sunset



Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.


2016 March 20


See Explanation. Clicking on the picture will download the highest resolution version available.



A Picturesque Equinox Sunset
Image Credit & Copyright: Roland Christen
Explanation: What's that at the end of the road? The Sun. Many towns have roads that run east - west, and on two days each year, the Sun rises and sets right down the middle. Today is one of those days: an equinox. Not only is today a day of equal night ("aequus"-"nox") and day time, but also a day when the sun rises precisely to the east and sets due west. Featured here is a picturesque road in northwest Illinois, USA that runs approximately east -west. The image was taken one year ago today, during the March Equinox of 2015, and shows the Sun down the road at sunset. In many cultures, this March equinox is taken to be the first day of a season, typically spring in Earth's northern hemisphere, and autumn in the south. Does your favorite street run east - west? Tonight at sunset, with a quick glance, you can actually find out.

Quiz (really hard): What road is pictured?
Tomorrow's picture: alaskan sundogs
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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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Posted by Nelio Inacio at 1:11 PM 0 comments

Alaskan Moondogs

Alaskan Moondogs: APOD: 2016 March 21 - Alaskan Moondogs



Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.


2016 March 21


See Explanation. Clicking on the picture will download the highest resolution version available.



Alaskan Moondogs
Image Credit & Copyright: Sebastian Saarloos
Explanation: What's happened to the sky? Moonlight illuminates a snowy scene in this night land and skyscape made on 2013 January from Lower Miller Creek, Alaska, USA. Overexposed near the mountainous western horizon is the first quarter Moon itself, surrounded by an icy halo and flanked left and right by moondogs. Sometimes called mock moons, a more scientific name for the luminous apparitions is paraselenae (plural). Analogous to a sundog or parhelion, a paraselene is produced by moonlight refracted through thin, hexagonal, plate-shaped ice crystals. As determined by the crystal geometry, paraselenae are seen at an angle of 22 degrees or more from the Moon. Compared to the bright lunar disk, paraselenae are faint and easier to spot when the Moon is low.

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Tomorrow's picture: gravity's rainbows
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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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Posted by Nelio Inacio at 1:11 PM 0 comments

The Great Nebula in Carina

The Great Nebula in Carina: APOD: 2016 March 23 - The Great Nebula in Carina



Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.


2016 March 23


See Explanation. Clicking on the picture will download the highest resolution version available.



The Great Nebula in Carina
Image Credit & Copyright: Damian Peach/SEN
Explanation: In one of the brightest parts of Milky Way lies a nebula where some of the oddest things occur. NGC 3372, known as the Great Nebula in Carina, is home to massive stars and changing nebulas. The Keyhole Nebula (NGC 3324), the bright structure just above the image center, houses several of these massive stars and has itself changed its appearance. The entire Carina Nebula spans over 300 light years and lies about 7,500 light-years away in the constellation of Carina. Eta Carinae, the most energetic star in the nebula, was one of the brightest stars in the sky in the 1830s, but then faded dramatically. Eta Carinae is the brightest star near the image center, just left of the Keyhole Nebula. While Eta Carinae itself maybe on the verge of a supernova explosion, X-ray images indicate that much of the Great Carina Nebula has been a veritable supernova factory.

Tomorrow's picture: open space
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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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Posted by Nelio Inacio at 1:09 PM 0 comments

Hickson 91 in Piscis Austrinus

Hickson 91 in Piscis Austrinus: APOD: 2016 March 24 - Hickson 91 in Piscis Austrinus



Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.


2016 March 24


See Explanation. Clicking on the picture will download the highest resolution version available.



Hickson 91 in Piscis Austrinus
Image Credit & Copyright: CHART32 Team, Processing - Johannes Schedler
Explanation: Scanning the skies for galaxies, Canadian astronomer Paul Hickson and colleagues identified some 100 compact groups of galaxies, now appropriately called Hickson Compact Groups (HCGs). This sharp telescopic image captures one such galaxy group, HCG 91, in beautiful detail. The group's three colorful spiral galaxies at the center of the field of view are locked in a gravitational tug of war, their interactions producing faint but visible tidal tails over 100,000 light-years long. Their close encounters trigger furious star formation. On a cosmic timescale the result will be a merger into a large single galaxy, a process now understood to be a normal part of the evolution of galaxies, including our own Milky Way. HCG 91 lies about 320 million light-years away in the constellation Piscis Austrinus. But the impressively deep image also catches evidence of fainter tidal tails and galaxy interactions close to 2 billion light-years distant.

Tomorrow's picture: close comet
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Posted by Nelio Inacio at 1:09 PM 0 comments

Thursday, March 24, 2016

UFO Attack Video | Real UFO Attack Caught On Camera Over Russia | UFO Si...





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Breaking-UFO Attack Caught Over Syria | UFO Attack Video 2016 | UFO Sigh...





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BEST UFO SIGHTINGS WORLDWIDE of 2015 Compilation Section 51





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UFO, how it works? Lets go inside of alien spaceship!





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UFO SIGHTINGS - Best UFO PICS EVER! REAL PHOTOS!





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Tuesday, March 22, 2016

KGB Agent Record of Alien Races [Leaked]





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Third Reich - Operation UFO (Nazi Base In Antarctica) HD - UFO Documentary





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The NAZI UFO Conspiracy & Secret Technology [Full Documentary Films]





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Real UFO Footage USA Fighter Jets vs UFO | OVNI (UFO) sobre Toledo Spai...





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Sunday, March 20, 2016

18 Billion Solar Mass Black Hole Rotates At 1/3 Speed Of Light

18 Billion Solar Mass Black Hole Rotates At 1/3 Speed Of Light:



Black-hole-powered galaxies called blazars are the most common sources detected by NASA's Fermi Gamma-ray Space Telescope. As matter falls toward the supermassive black hole at the galaxy's center, some of it is accelerated outward at nearly the speed of light along jets pointed in opposite directions. When one of the jets happens to be aimed in the direction of Earth, as illustrated here, the galaxy appears especially bright and is classified as a blazar. Credits: M. Weiss/CfA


Way up in the constellation Cancer there's a 14th magnitude speck of light you can claim in a 10-inch or larger telescope. If you saw it, you might sniff at something so insignificant, yet it represents the final farewell of chewed up stars as their remains whirl down the throat of an 18 billion solar mass black hole, one of the most massive known in the universe.Astronomers know the object as OJ 287, a quasar that lies 3.5 billion light years from Earth. Quasars or quasi-stellar objects light up the centers of many remote galaxies. If we could pull up for a closer look, we'd see a brilliant, flattened accretion disk composed of heated star-stuff spinning about the central black hole at extreme speeds.As matter gets sucked down the hole, jets of hot plasma and energetic light shoot out perpendicular to the disk. And if we're so privileged that one of those jet happens to point directly at us, we call the quasar a "blazar". Variability of the light streaming from the heart of a blazar is so constant, the object practically flickers.A recent observational campaign involving more than two dozen optical telescopes and NASA's space based SWIFT X-ray telescope allowed a team of astronomers to measure very accurately the rotational rate the black hole powering OJ 287 at one third the maximum spin rate — about 56,000 miles per second (90,000 kps) —  allowed in General Relativity  A careful analysis of these observations show that OJ 287 has produced close-to-periodic optical outbursts at intervals of approximately 12 years dating back to around 1891. A close inspection of newer data sets reveals the presence of double-peaks in these outbursts.To explain the blazar's behavior, Prof. Mauri Valtonen of the University of Turku (Finland) and colleagues developed a model that beautifully explains the data if the quasar OJ 287 harbors not one buy two unequal mass black holes — an 18 billion mass one orbited by a smaller black hole.OJ 287 is visible due to the streaming of matter present in the accretion disk onto the largest black hole. The smaller black hole passes through the larger's the accretion disk during its orbit, causing the disk material to briefly heat up to very high temperatures. This heated material flows out from both sides of the accretion disk and radiates strongly for weeks, causing the double peak in brightness.The orbit of the smaller black hole also precesses similar to how Mercury's orbit precesses. This changes when and where the smaller black hole passes through the accretion disk.  After carefully observing eight outbursts of the black hole, the team was able to determine not only the black holes' masses but also the precession rate of the orbit. Based on Valtonen's model, the team predicted a flare in late November 2015, and it happened right on schedule.The timing of this bright outburst allowed Valtonen and his co-workers to directly measure the rotation rate of the more massive black hole to be nearly 1/3 the speed of light. I've checked around and as far as I can tell, this would make it the fastest spinning object we know of in the universe. Getting dizzy yet?

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Posted by Nelio Inacio at 4:18 PM 0 comments

Kuiper Belt Objects Point The Way To Planet 9

Kuiper Belt Objects Point The Way To Planet 9:



Artist's impression of Planet Nine as an ice giant eclipsing the central Milky Way. Credit: ESO/Tomruen/nagualdesign


On January 20th, 2016, researchers Konstantin Batygin and Michael E. Brown of Caltech announced that they had found evidence that hinted at the existence of a massive planet at the edge of the Solar System. Based on mathematical modeling and computer simulations, they predicted that this planet would be a super-Earth, two to four times Earth's size and 10 times as massive. They also estimated that, given its distance and highly elliptical orbit, it would take 10,000 - 20,000 years to orbit the Sun.Since that time, many researchers have responded with their own studies about the possible existence of this mysterious "Planet 9". One of the latest comes from the University of Arizona, where a research team from the Lunar and Planetary Laboratory have indicated that the extreme eccentricity of distant Kuiper Belt Objects (KBOs) might indicate that they crossed paths with a massive planet in the past.For some time now, it has been understood that there are a few known KBOs who's dynamics are different than those of other belt objects. Whereas most are significantly controlled by the gravity of the gas giants planets in their current orbits (particularly Neptune), certain members of the scattered disk population of the Kuiper Belt have unusually closely-spaced orbits.When Batygin and Brown first announced their findings back in January, they indicated that these objects instead appeared to be highly clustered with respect to their perihelion positions and orbital planes. What's more, their calculation showed that the odds of this being a chance occurrence were extremely low (they calculated a probability of 0.007%).Instead, they theorized that it was a distant eccentric planet that was responsible for maintaining the orbits of these KBOs. In order to do this, the planet in question would have to be over ten times as massive as Earth, and have an orbit that lay roughly on the same plane (but with a perihelion oriented 180° away from those of the KBOs).Such a planet not only offered an explanation for the presence of high-perihelion Sedna-like objects - i.e. planetoids that have extremely eccentric orbits around the Sun. It would also help to explain where distant and highly inclined objects in the outer Solar System come from, since their origins have been unclear up until this point.In a paper titled "Coralling a distant planet with extreme resonant Kuiper belt objects", the University of Arizona research team - which included Professor Renu Malhotra, Dr. Kathryn Volk, and Xianyu Wang - looked at things from another angle. If in fact Planet 9 were crossing paths with certain high-eccentricity KBOs, they reasoned, it was a good bet that its orbit was in resonance with these objects.To break it down, small bodies are ejected  from the Solar System all the time due to encounters with larger objects that perturb their orbits. In order to avoid being ejected, smaller bodies need to be protected by orbital resonances. While the smaller and larger objects may pass within each others' orbital path, they are never close enough that they would able to exert a significant influence on each other.This is how Pluto has remained a part of the Solar System, despite having an eccentric orbit that periodically cross Neptune's path. Though Neptune and Pluto cross each others orbit, they are never close enough to each other that Neptune's influence would force Pluto out of our Solar System. Using this same reasoning, they hypothesized that the KBOs examined by Batygin and Brown might be in an orbital resonance with the Planet 9.As Dr.  Malhotra, Volk and Wang told Universe Today via email:

"The extreme Kuiper belt objects we investigate in our paper are distinct from the others because they all have very distant, very elliptical orbits, but their closest approach to the Sun isn’t really close enough for them to meaningfully interact with Neptune. So we have these six observed objects whose orbits are currently fairly unaffected by the known planets in our Solar System. But if there’s another, as yet unobserved planet located a few hundred AU from the Sun, these six objects would be affected by that planet."
After examining the orbital periods of these six KBOs - Sedna, 2010 GB174, 2004 VN112, 2012 VP113, and 2013 GP136 - they concluded that a hypothetical planet with an orbital period of about 17,117 years (or a semimajor axis of about 665 AU), would have the necessary period ratios with these four objects. This would fall within the parameters estimated by Batygin and Brown for the planet's orbital period (10,000 - 20,000 years).Their analysis also offered suggestions as to what kind of resonance the planet has with the KBOs in question. Whereas Sedna's orbital period would have a 3:2 resonance with the planet, 2010 GB174 would be in a 5:2 resonance, 2994 VN112 in a 3:1, 2004 VP113 in 4:1, and 2013 GP136 in 9:1. These sort of resonances are simply not likely without the presence of a larger planet.

"For a resonance to be dynamically meaningful in the outer Solar System, you need one of the objects to have enough mass to have a reasonably strong gravitational effect on the other," said the research team. "The extreme Kuiper belt objects aren’t really massive enough to be in resonances with each other, but the fact that their orbital periods fall along simple ratios might mean that they each are in resonance with a massive, unseen object."

But what is perhaps most exciting is that their findings could help to narrow the range of Planet 9's possible location. Since each orbital resonance provides a geometric relationship between the bodies involved, the resonant configurations of these KBOs can help point astronomers to the right spot in our Solar System to find it.

But of course, Malhotra and her colleagues freely admit that several unknowns remain, and further observation and study is necessary before Planet 9 can be confirmed:

"There are a lot of uncertainties here. The orbits of these extreme Kuiper belt objects are not very well known because they move very slowly on the sky and we’ve only observed very small portions of their orbital motion. So their orbital periods might differ from the current estimates, which could make some of them not resonant with the hypothetical planet. It could also just be chance that the orbital periods of the objects are related; we haven’t observed very many of these types of objects, so we have a limited set of data to work with."
Ultimately, astronomers and the rest of us will simply have to wait on further observations and calculations. But in the meantime, I think we can all agree that the possibility of a 9th Planet is certainly an intriguing one! For those who grew up thinking that the Solar System had nine planets, these past few years (where Pluto was demoted and that number fell to eight) have been hard to swallow.But with the possible confirmation of this Super-Earth at the outer edge of the Solar System, that number could be pushed back up to nine soon enough!Further Reading: arXiv.org

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Posted by Nelio Inacio at 4:18 PM 0 comments

Cassini Watches Star Through Enceladus’ Plume

Cassini Watches Star Through Enceladus’ Plume:

When the Cassini probe first saw the plumes coming from Saturn’s moon Enceladus, it was a surprise. When it dipped through the plumes, some questions about the basic nature of the phenomenon were answered. But there are still many more questions, and today Cassini has an opportunity to find some answers.

Cassini will be in a perfect position today to observe the light from Epsilon Orionis, the central star in Orion’s belt, as it passes through Enceladus’ plume. This type of observation is known as a stellar occultation, and it promises to provide new information about the composition and density of the plume. Cassini’s Ultraviolet Imaging Spectrograph (UVIS) will do the capturing, and once the information is relayed back to Earth, it will be analyzed for clues.

An artist's impression of the plumes coming from Enceladus. Image: NASA/JPL.
An artist’s impression of the plumes coming from Enceladus. Image: NASA/JPL.
We already know a few things about Enceladus’ plumes. First of all, Enceladus itself is any icy world, with subsurface oceans. The moon is locked in an orbital resonance, which creates its eccentric orbit. This eccentric orbit is responsible for heating the south polar oceans, which drives material through the ice sheets and creates its stunning plumes, in a process known as cryovolcanism. (Radioactive decay might also have something to do with heating.)

Cassini has been at Saturn’s system for 12 years, and has gradually painted a more detailed picture of Enceladus. Over time, we’ve learned that the plumes themselves are similar to what comets are made of. Cassini initially detected mostly water vapor, with traces of molecular nitrogen, methane, and carbon dioxide. Later, the presence of the hydrocarbons propane, formaldehyde, and acetylene was confirmed.

This is all very interesting, but why would anyone other than chemistry geeks care? Because the universe, including our Solar System, is largely a cold, sterile place. And the plumes coming from Enceladus indicate the presence of water, potentially warm, salty, water at that. And warm water might mean life, or the potential for life.

Cassini has previously observed two other stellar occultations. But with today’s observation, we stand to learn even more about the plumes of Enceladus. We’ll not only learn more about their density and composition, but since is the third such occultation to be observed, we’ll learn something about the plume’s behaviour over time. We probably won’t learn anything definitive about Enceladus’ life-supporting potential, but we will almost certainly find another piece of the puzzle, and fill in a blank spot in our knowledge.

And that’s what science is all about.

The post Cassini Watches Star Through Enceladus’ Plume appeared first on Universe Today.

Posted by Nelio Inacio at 4:17 PM 0 comments

Comet Created Chaos In Mars’ Magnetic Field

Comet Created Chaos In Mars’ Magnetic Field:



Comet Siding Spring (C/2007 Q3) as imaged in the infrared by the WISE space telescope. The image was taken January 10, 2010 when the comet was 2.5AU from the Sun. Credit: NASA/JPL-Caltech/UCLA


In the Autumn of 2014, NASA's Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft arrived at Mars and entered into orbit. MAVEN wasn't the only visitor to arrive at Mars at that time though, as comet Siding Spring (C/2013 A1) also showed up at Mars. Most of MAVEN's instruments were shut down to protect sensitive electronics from Siding Spring's magnetic field. But the magnetometer aboard the spacecraft was left on, which gave MAVEN a great view of the interaction between the planet and the comet.Unlike Earth, which has a powerful magnetosphere created by its rotating metal core, Mars' magnetosphere is created by plasma in its upper atmosphere, and is not very powerful. (Mars may have had a rotating metal core in the past, and a stronger magnetosphere because of it, but that's beside the point.) Comet Siding Spring is small, with its nucleus being only about one half a kilometer. But its magnetosphere is situated in its coma, the long 'tail' of the comet that stretches out for a million kilometers.When Siding Spring approached Mars, it came to within 140,000 km (87,000 miles) of the planet. But the comet's coma nearly touched the surface of the planet, and during that hours-long encounter, the magnetic field from the comet created havoc with Mars' magnetic field. And MAVEN's magnetometer captured the event.Jared Espley is a member of the MAVEN team at Goddard Space Flight Center. He said of the Mars/Siding Spring event, "We think the encounter blew away part of Mars’ upper atmosphere, much like a strong solar storm would.”“The main action took place during the comet’s closest approach,” said Espley, “but the planet’s magnetosphere began to feel some effects as soon as it entered the outer edge of the comet’s coma.”Espley and his colleagues describe the event as a tide that washed over the Martian magnetosphere. Comet Siding Spring's tail has a magnetosphere due to its interactions with the solar wind. As the comet is heated by the sun, plasma is generated, which interacts in turn with the solar wind, creating a magnetosphere. And like a tide, the effects were subtle at first, and the event played out over several hours as the comet passed by the planet.Siding Spring's magnetic tide had only a subtle effect on Mars at first. Normally, Mars' magnetosphere is situated evenly around the planet, but as the comet got closer, some parts of the planet's magnetosphere began to realign themselves. Eventually the effect was so powerful that the field was thrown into chaos, like a flag flapping every which way in a powerful wind. It took Mars a while to recover from this encounter as the field took several hours to recover.MAVEN's task is to gain a better understanding of the interactions between the Sun's solar wind and Mars. So being able to witness the effect that Siding Spring had on Mars is an added bonus. Bruce Jakosky, from the University of Colorado's Laboratory for Atmospheric and Space Physics in Boulder, is one of MAVEN's principal investigators. "By looking at how the magnetospheres of the comet and of Mars interact with each other," said Jakosky, "we’re getting a better understanding of the detailed processes that control each one.”

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Posted by Nelio Inacio at 4:17 PM 0 comments

DSCOVR Captures EPIC Views of the March 2016 Eclipse

DSCOVR Captures EPIC Views of the March 2016 Eclipse:



The Moon's shadow is cast across Indonesia in this view from the DSCOVR spacecraft, March 9, 2016. (Courtesy of the DSCOVR EPIC team.)


On March 8, 2016 (March 9 local time) the Moon briefly blocked the light from the Sun in what was the only total solar eclipse of the year. The event was visible across portions of southeast Asia, Indonesia, and Micronesia, and was observed by both skywatchers on the ground in person and those watching live online around the world. While to most the view was of a silhouetted Moon slowly carving away the disk of the Sun before totality revealed a shimmering corona, the view from space looking back at Earth showed the Moon's dark shadow passing over islands, clouds, and sea.The picture above was acquired by NASA's EPIC (Earth Polychromatic Imaging Camera) instrument on board the DSCOVR spacecraft, operated by NOAA. It's one of twelve images captured during the course of the eclipse from DSCOVR's position at L1, 1.6 million km (nearly 1 million miles) away.Read more: What Are Lagrange Points?Launched Feb. 11, 2015, DSCOVR observes both Earth and incoming space weather from the Sun, providing up to an hour of early warning of solar storm activity. Its location gives it a view of a constantly-illuminated Earth, since DSCOVR is always positioned between it and the Sun.*Watch an animation of the Moon's shadow traveling northeast across the Pacific here, and for more images of the March 2016 total eclipse (captured from the ground) check out this article by David Dickinson.The next solar eclipse in 2016 will be on September 1, and will be a partial/annular eclipse visible from Africa and the Indian Ocean. The next total solar eclipse will occur on Aug. 21, 2017, during which the path of totality will cross the United States from coast to coast.Source: NASA's Earth ObservatoryNote: The March 2016 eclipse was also captured by Japan's Himawari-8 geostationary weather satellite; watch the sequence from that spacecraft below:*DSCOVR is actually in a "halo orbit" around L1, which affects its viewing angle of Earth—this is why we see the Moon's shadow and not the Moon itself (and when it does see the Moon in front of Earth there isn't a shadow or eclipse.) Read more on Phil Plait's Slate article here.

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Posted by Nelio Inacio at 4:16 PM 0 comments

First Tomatoes, Peas Harvested From Simulated Martian Soil

First Tomatoes, Peas Harvested From Simulated Martian Soil:



Researchers at Wageningen University in the Netherlands have harvested tomatoes and other vegetables grown in simulated Martian soil. Image: regan76 CC BY 2.0


We're a long ways away from colonizing another planet—depending on who you talk to—but it's not too soon to start understanding how we might do it when the time comes. Growing enough food will be one of the primary concerns for any future settlers of Mars. With that in mind, researchers at the Wageningen University and Research Centre in the Netherlands have created simulated Martian soil and used it to grow food crops.This is actually the second experiment the team has performed with simulated soil, and the results were promising. The team harvested not only tomatoes and peas, but also rye, garden rocket, radish, and watercress. But it's not just the edibles that were promising, it was the overall ability of the simulated soil to produce biomass in general.  According to the researchers, the soil produced biomass equal to that produced by Earth soil, which was used as a control.The team also grew crops in simulated Moon soil, to understand how that soil performed, but it produced much less biomass, and only the humble spinach was able to grow in it. The simulated Martian and Lunar soils were provided by NASA. The Martian soil came from a Hawaiian volcano, and the Lunar soil came from a desert in Arizona.The soil used was not exactly the same as the soil you would scoop up if you were on the Moon or Mars. It was amended with organic matter in the form of manure and fresh cut grass. While this may sound like a 'cheat', it's no different than how gardens are grown on Earth, with gardeners using manure, compost, grass clippings, leaves, and even seaweed to provide organic matter.Of course, none of these soil amendments will be available on the Moon or Mars, and we won't be sending a supply ship full of manure. Colonists will have to make use of all of the inedible parts of their crops—and human feces—to provide the organic material necessary for plant growth. It'll be a closed system, after all.The crops were grown in a controlled environment, where temperature, humidity, and other factors were kept within Earthly parameters. Any crops grown on Mars will be grown in the same controlled environments, at least until genetic modification can create plants able to withstand the increased radiation and other factors.A problem facing colonists trying to grow food on Mars is the heavy metal content of the soil. Mars soil contains mercury, lead, cadmium, and arsenic, which are all toxic to humans. The presence of these elements doesn't bother the plants; they just keep growing. But any crops grown in this soil will have to be tested for toxicity before they can be consumed. This is the next experiment that the team has planned.Researchers at the Wageningen University are currently crowdfunding for this next experiment. If you'd like to contribute, check out their page here. 

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Posted by Nelio Inacio at 4:15 PM 0 comments

The Early Universe Was All About Galactic Hook Ups

The Early Universe Was All About Galactic Hook Ups:



Artist's illustration of the Andromeda galaxy and the Milky Way merging, based on data from the Hubble Space Telescope. Credit: NASA


In about 4 billion years, scientists estimate that the Andromeda and the Milky Way galaxies are expected to collide, based on data from the Hubble Space Telescope. And when they merge, they will give rise to a super-galaxy that some are already calling Milkomeda or Milkdromeda (I know, awful isn't it?) While this may sound like a cataclysmic event, these sorts of galactic collisions are quite common on a cosmic timescale.As an international group of researchers from Japan and California have found, galactic "hookups" were quite common during the early universe. Using data from the Hubble Space Telescope and the Subaru Telescope at in Mauna Kea, Hawaii, they have discovered that 1.2 billion years after the Big Bang, galactic clumps grew to become large galaxies by merging. As part of the Hubble Space Telescope (HST) "Cosmic Evolution Survey (COSMOS)", this information could tell us a great about the formation of the early universe.Previous research has shown that some 200 million years after the Big Bang, the universe was filled with pre-galactic clumps. These cold gas clouds were roughly one-hundred times smaller and one-million times less massive than modern galaxies. It is from these clumps of gas that the first stars and galaxies are believed to have formed.After the first small galaxies were formed, they began to merge together, forming the larger galaxies we see today - i.e. which contain hundreds of billions of stars and measure thousands of light years across. For some time, scientists have been trying to see galaxies as they existed in the early universe, at a time when they were still actively forming stars.Unfortunately, given the distances involved (13 billion light years) and the fact that most of the galaxies in the young universe were quite small, getting a sense of their detailed structures has so far been impossible. However, the research team - which included members from Ehime University, Nagoya University and Tohoku University in Japan and the Space Telescope Science Institute (STScI) and the California Institute of Technology in the US - used the Subaru Telescope and the Advanced Camera for Surveys (ACS) on the Hubble Space Telescope.Whereas the Subaru Telescope helped locate galaxies in the early universe with its wide field of view, the high spatial resolution of Hubble's ACS was used to investigate the details of their shapes and internal structures. Using this two-pronged approach, the team then looked back 12.6 billion years, roughly 1.2 billion years after the Big Bang, and noted something very interesting about the galactic structures they saw.In a paper published by The Astrophysical Journals, the team indicated that out of the 54 galaxies they observed, 8 had double-component structures, which indicated that they were the result of two galaxies merging with each other. In addition, they found that with the remaining 46 galaxies, their elongated shapes - as well as a correlation between their ellipticity and size - might indicate that they too were merging galaxies.After testing this theory, the team found that they were in fact correct. In all cases, the galaxies only appeared as single entities because the distance between their two constituents was so small. This theory was borne out when they looked for a possible correlation between the size of the galaxies and their level of star formation. Again, they were proven correct, as the smaller and more closely-merged galaxies showed a higher rate of activity.All of this indicated that galactic mergers (or "hookups", to use the bawdy term) were a common occurrence in the early universe. As Dr. Nick Z. Scoville - the Francis L. Moseley Professor of Astronomy at Caltech, and an author of the study - told Universe Today via email:

"This work uses very deep imaging from both Hubble and the Subaru telescope to establish a beautiful correlation between the sizes and elongation of galaxies when the universe was only 10% of its present age. The very high resolution Hubble images are used to show that the elongation of the galaxy images seen in the ultra sensitive Subaru imaging is due to overlap multiple galaxies. This research clearly shows the prevalence of galaxy merging in building up the earliest galaxies and promoting more rapid formation of stars."
Prior to this, astronomers were in the habit of thinking that single structures observed in the early Universe by Hubble were in fact single galaxies. In contrast, this research suggests that these small, early galaxies actually consisted of two or even more galaxies. This is sure to have implications for the study of galactic formation and evolution, which predicts that small galaxies evolved through successive mergers to create the larger ones we know today.As for what's next, that will likely have to wait upon the deployment of the next generation of space telescopes. Currently, astronomers have a difficult time seeing clear to objects that are so very distant from Earth. But with the improved instruments that will be put into service in the coming years, scientists hope that they might be able to take the next leap, which will likely involve resolving the internal structure of early galaxies.For example, when the James Webb Space Telescope (JWST) is deployed, astronomers believe they will have the power and the spatial resolution needed to see even further into the past, and with greater clarity. And we can expect they will have plenty to say about the many galaxies they see, located billions of lights year away and billions of years in the past!Further Reading: National Astronomical Observatory of Japan - Subaru Telescope

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Posted by Nelio Inacio at 4:14 PM 0 comments
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