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A Complete Guide to the March 20th Total Solar Eclipse

March 12, 2015 / / 0 Comments


Credit
Totality! The 2012 total solar eclipse as seen from Australia. Credit and copyright: www.hughca.com.



Excerpt from universetoday.com



The first of two eclipse seasons for the year is upon us this month, and kicks off with the only total solar eclipse for 2015 on Friday, March 20th.

And what a bizarre eclipse it is. Not only does this eclipse begin just 15 hours prior to the March equinox marking the beginning of astronomical spring in the northern hemisphere, but the shadow of totality also beats path through the high Arctic and ends over the North Pole.


Credit:
An animation of the March 20th eclipse. Credit: NASA/GSFC/AT Sinclair.


Already, umbraphiles — those who chase eclipses — are converging on the two small tracts of terra firma where the umbra of the Moon makes landfall: the Faroe and Svalbard islands. All of Europe, the northern swath of the African continent, north-central Asia and the Middle East will see a partial solar eclipse, and the eclipse will be deeper percentage-wise the farther north you are .
2015 features four eclipses in all: two total lunars and two solars, with one total solar and one partial solar eclipse. Four is the minimum number of eclipses that can occur in a calendar year, and although North America misses out on the solar eclipse action this time ’round, most of the continent gets a front row seat to the two final total lunar eclipses of the ongoing tetrad on April 4th and September 28th.

How rare is a total solar eclipse on the vernal equinox? Well, the last total solar eclipse on the March equinox occurred back in 1662 on March 20th. There was also a hybrid eclipse — an eclipse which was annular along a portion of the track, and total along another — on March 20th, 1681. But you won’t have to wait that long for the next, as another eclipse falls on the northward equinox on March 20th, 2034.


Credit
The path of the March 20th eclipse across Europe, including start times for the partial phases, and the path of totality, click to enlarge. For more maps showing the percentage of occlusion, elevation, and more, click here. Credit: Michael Zeiler/GreatAmercianEclipse.com.


Note that in the 21st century, the March equinox falls on March 20th, and will start occasionally falling on March 19th in 2044. We’re also in that wacky time of year where North America has shifted back to ye ‘ole Daylight Saving (or Summer) Time, while Europe makes the change after the eclipse on March 29th. It really can wreak havoc with those cross-time zone plans, we know…
The March 20th eclipse also occurs only a day after lunar perigee, which falls on March 19th at 19:39 UT. This is also one of the closer lunar perigees for 2015 at 357,583 kilometres distant, though the maximum duration of totality for this eclipse is only 2 minutes and 47 seconds just northeast of the Faroe Islands.


Credit:
Views from selected locales in Europe and Africa. Credit: Stellarium.



This eclipse is number 61 of 71 in solar saros series 120, which runs from 933 to 2754 AD. It’s also the second to last total in the series, with the final total solar eclipse for the saros cycle occurring one saros later on March 30th, 2033.



What would it look like to sit at the North Pole and watch a total solar eclipse on the first day of Spring? It would be a remarkable sight, as the disk of the Sun skims just above the horizon for the first time since the September 2014 equinox. Does this eclipse occur at sunrise or sunset as seen from the pole? It would be a rare spectacle indeed!


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An equinoctal eclipse as simulated from the North Pole. Credit: Stellarium.






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Practicing eclipse safety in Africa. Credit: Michael Zeiler/GreatAmericanEclipse.com


Safety is paramount when observing the Sun and a solar eclipse. Eye protection is mandatory during all partial phases across Europe, northern Asia, North Africa and the Middle East. A proper solar filter mask constructed of Baader safety film is easy to construct, and should fit snugly over the front aperture of a telescope. No. 14 welder’s goggles are also dense enough to look at the Sun, as are safety glasses specifically designed for eclipse viewing. Observing the Sun via projection or by using a pinhole projector is safe and easy to do.


Credit
A solar filtered scope ready to go in Tucson, Arizona. Credit: photo by author.

Weather is always the big variable in the days leading up to any eclipse. Unfortunately, March in the North Atlantic typically hosts stormy skies, and the low elevation of the eclipse in the sky may hamper observations as well. From the Faroe Islands, the Sun sits 18 degrees above the horizon during totality, while from the Svalbard Islands it’s even lower at 12 degrees in elevation. Much of Svalbard is also mountainous, making for sunless pockets of terrain that will be masked in shadow on eclipse day. Mean cloud amounts for both locales run in the 70% range, and the Eclipser website hosts a great in-depth climatology discussion for this and every eclipse.


Credit
The view of totality and the planets as seen from the Faroe Islands. Credit: Starry Night.


But don’t despair: you only need a clear view of the Sun to witness an eclipse!

Solar activity is also another big variable. Witnesses to the October 23rd, 2014 partial solar eclipse over the U.S. southwest will recall that we had a massive and very photogenic sunspot turned Earthward at the time. The Sun has been remarkably calm as of late, though active sunspot region 2297 is developing nicely. It will have rotated to the solar limb come eclipse day, and we should have a good grasp on what solar activity during the eclipse will look like come early next week.

And speaking of which: could an auroral display be in the cards for those brief few minutes of totality? It’s not out of the question, assuming the Sun cooperates.  Of course, the pearly white corona of the Sun still gives off a considerable amount of light during totality, equal to about half the brightness of a Full Moon. Still, witnessing two of nature’s grandest spectacles — a total solar eclipse and the aurora borealis — simultaneously would be an unforgettable sight, and to our knowledge, has never been documented!

We also put together some simulations of the eclipse as seen from Earth and space:




Note that an area of southern Spain may witness a transit of the International Space Station during the partial phase of the eclipse. This projection is tentative, as the orbit of the ISS evolves over time. Be sure to check CALSky for accurate predictions in the days leading up to the eclipse.


Credit
The ISS transits the Sun during the eclipse around 9:05 UT as seen from southern Spain. Credit: Starry Night.


Can’t make it to the eclipse? Live in the wrong hemisphere? There are already a few planned webcasts for the March 20th eclipse:


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Billionaire teams up with NASA to mine the moon

March 10, 2015 / / 0 Comments




Excerpt from cnbc.com
By Susan Caminiti



Moon Express, a Mountain View, California-based company that's aiming to send the first commercial robotic spacecraft to the moon next year, just took another step closer toward that lofty goal. 

Earlier this year, it became the first company to successfully test a prototype of a lunar lander at the Kennedy Space Center in Florida. The success of this test—and a series of others that will take place later this year—paves the way for Moon Express to send its lander to the moon in 2016, said company co-founder and chairman Naveen Jain.

Moon Express conducted its tests with the support of NASA engineers, who are sharing with the company their deep well of lunar know-how. The NASA lunar initiative—known as Catalyst—is designed to spur new commercial U.S. capabilities to reach the moon and tap into its considerable resources.In addition to Moon Express, NASA is also working with Astrobotic Technologies of Pittsburgh, Pennsylvania, and Masten Space Systems of Mojave, California, to develop commercial robotic spacecrafts. 

Jain said Moon Express also recently signed an agreement to take over Space Launch Complex 36 at Cape Canaveral. The historic launchpad will be used for Moon Express's lander development and flight-test operations. Before it was decommissioned, the launchpad was home to NASA's Atlas-Centaur rocket program and its Surveyor moon landers.

"Clearly, NASA has an amazing amount of expertise when it comes to getting to the moon, and it wants to pass that knowledge on to a company like ours that has the best chance of being successful," said Jain, a serial entrepreneur who also founded Internet companies Infospace and Intelius. He believes that the moon holds precious metals and rare minerals that can be brought back to help address Earth's energy, health and resource challenges. 

Among the moon's vast riches: gold, cobalt, iron, palladium, platinum, tungsten and Helium-3, a gas that can be used in future fusion reactors to provide nuclear power without radioactive waste. "We went to the moon 50 years ago, yet today we have more computing power with our iPhones than the computers that sent men into space," Jain said. "That type of exponential technological growth is allowing things to happen that was never possible before."

An eye on the Google prize

Source: MoonExpress

Helping to drive this newfound interest in privately funded space exploration is the Google Lunar X Prize. It's a competition organized by the X Prize Foundation and sponsored by Google that will award $30 million to the first company that lands a commercial spacecraft on the moon, travels 500 meters across its surface and sends high-definition images and video back to Earth—all before the end of 2016.

Moon Express is already at the front of the pack. In January it was awarded a $1 million milestone prize from Google for being the only company in the competition so far to test a prototype of its lander. "Winning the X prize would be a great thing," said Jain. "But building a great company is the ultimate goal with us." When it comes to space exploration, he added, "it's clear that the baton has been passed from the government to the private sector."

Testing in stages

Jain said Moon Express has been putting its lunar lander through a series of tests at the space center. The successful outing earlier this year involved tethering the vehicle—which is the size of a coffee table—to a crane in order to safely test its control systems. "The reason we tethered it to the crane is because the last thing we wanted was the aircraft to go completely haywire and hurt someone," he said. 

At the end of March, the company will conduct a completely free flight test with no tethering. The lander will take off from the pad, go up and sideways, then land back at the launchpad. "This is to test that the vehicle knows where to go and how to get back to the launchpad safely," Jain explained.


Once all these tests are successfully completed, Jain said the lander—called MX-1—will be ready to travel to the moon. The most likely scenario is that it will be attached to a satellite that will take the lander into a low orbit over the Earth. From there the MX-1 will fire its own rocket, powered by hydrogen peroxide, and launch from that orbit to complete its travel to the moon's surface. 

The lander's first mission is a one-way trip, meaning that it's not designed to travel back to the Earth, said Jain. "The purpose is to show that for the first time, a company has developed the technology to land softly on the moon," he said. "Landing on the moon is not the hard part. Landing softly is the hard part." 

That's because even though the gravity of the moon is one-sixth that of the Earth's, the lander will still be traveling down to the surface of the moon "like a bullet," Jain explained. Without the right calculations to indicate when its rockets have to fire in order to slow it down, the lander would hit the surface of the moon and break into millions of pieces. "Unlike here on Earth, there's no GPS on the moon to tell us this, so we have to do all these calculations first," he said. 

Looking ahead 15 or 20 years, Jain said he envisions a day when the moon is used as a sort of way station enabling easier travel for exploration to other planets. In the meantime, he said the lander's second and third missions could likely involve bringing precious metals, minerals and even moon rocks back to Earth. "Today, people look at diamonds as this rare thing on Earth," Jain said.
He added, "Imagine telling someone you love her by giving her the moon."

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Should Humanity Try to Contact Alien Civilizations?

March 1, 2015 / / 0 Comments



Some researchers want to use big radio dishes like the 305-meter Arecibo Observatory in Puerto Rico to announce our presence to intelligent aliens.

Excerpt from space.com
by Mike Wall

 Is it time to take the search for intelligent aliens to the next level?
For more than half a century, scientists have been scanning the heavens for signals generated by intelligent alien life. They haven't found anything conclusive yet, so some researchers are advocating adding an element called "active SETI" (search for extraterrestrial intelligence) — not just listening, but also beaming out transmissions of our own designed to catch aliens' eyes.

Active SETI "may just be the approach that lets us make contact with life beyond Earth," Douglas Vakoch, director of interstellar message composition at the SETI Institute in Mountain View, California, said earlier this month during a panel discussion at the annual meeting of the American Association for the Advancement of Science (AAAS) in San Jose.

Seeking contact


Vakoch envisions using big radio dishes such as the Arecibo Observatory in Puerto Rico to blast powerful, information-laden transmissions at nearby stars, in a series of relatively cheap, small-scale projects.

"Whenever any of the planetary radar folks are doing their asteroid studies, and they have an extra half an hour before or after, there's always a target star readily available that they can shift to without a lot of extra slough time," he said.

The content of any potential active SETI message is a subject of considerable debate. If it were up to astronomer Seth Shostak, Vakoch's SETI Institute colleague, we'd beam the entire Internet out into space.

"It's like sending a lot of hieroglyphics to the 19th century — they [aliens] can figure it out based on the redundancy," Shostak said during the AAAS discussion. "So, I think in terms of messages, we should send everything."

While active SETI could help make humanity's presence known to extrasolar civilizations, the strategy could also aid the more traditional "passive" search for alien intelligence, Shostak added.
"If you're going to run SETI experiments, where you're trying to listen for a putative alien broadcast, it may be very instructive to have to construct a transmitting project," he said. "Because now, you walk a mile in the Klingons' shoes, assuming they have them."

Cause for concern?

But active SETI is a controversial topic. Humanity has been a truly technological civilization for only a few generations; we're less than 60 years removed from launching our first satellite to Earth orbit, for example. So the chances are that any extraterrestrials who pick up our signals would be far more advanced than we are. 

This likelihood makes some researchers nervous, including famed theoretical physicist Stephen Hawking.

"Such advanced aliens would perhaps become nomads, looking to conquer and colonize whatever planets they could reach," Hawking said in 2010 on an episode of "Into the Universe with Stephen Hawking," a TV show that aired on the Discovery Channel. "If so, it makes sense for them to exploit each new planet for material to build more spaceships so they could move on. Who knows what the limits would be?"

Astrophysicist and science fiction author David Brin voiced similar concerns during the AAAS event, saying there's no reason to assume that intelligent aliens would be altruistic.

"This is an area in which discussion is called for," Brin said. "What are the motivations of species that they might carry with them into their advanced forms, that might color their cultures?"

Brin stressed that active SETI shouldn't be done in a piecemeal, ad hoc fashion by small groups of astronomers.

"This is something that should be discussed worldwide, and it should involve our peers in many other specialties, such as history," he said. "The historians would tell us, 'Well, gee, we have some examples of first-contact scenarios between advanced technological civilizations and not-so-advanced technological civilizations.' Gee, how did all of those turn out? Even when they were handled with goodwill, there was still pain."

Out there already

Vakoch and Shostak agreed that international discussion and cooperation are desirable. But Shostak said that achieving any kind of consensus on the topic of active SETI may be difficult. For example, what if polling reveals that 60 percent of people on Earth are in favor of the strategy, while 40 percent are opposed?

"Do we then have license to go ahead and transmit?" Shostak said. "That's the problem, I think, with this whole 'let's have some international discussion' [idea], because I don't know what the decision metric is."

Vakoch and Shostak also said that active SETI isn't as big a leap as it may seem at first glance: Our civilization has been beaming signals out into the universe unintentionally for a century, since the radio was invented.

"The reality is that any civilization that has the ability to travel between the stars can already pick up our accidental radio and TV leakage," Vakoch said. "A civilization just 200 to 300 years more advanced than we are could pick up our leakage radiation at a distance of several hundred light-years. So there are no increased dangers of an alien invasion through active SETI."

But Brin disputed this assertion, saying the so-called "barn door excuse" is a myth.

"It is very difficult for advanced civilizations to have picked us up at our noisiest in the 1980s, when we had all these military radars and these big television antennas," he said.

Shostak countered that a fear of alien invasion, if taken too far, could hamper humanity's expansion throughout the solar system, an effort that will probably require the use of high-powered transmissions between farflung outposts.

"Do you want to hamstring all that activity — not for the weekend, not just shut down the radars next week, or active SETI this year, but shut down humanity forever?" Shostak said. "That's a price I'm not willing to pay."

So the discussion and debate continues — and may continue for quite some time.

"This is the only really important scientific field without any subject matter," Brin said. "It's an area in which opinion rules, and everybody has a very fierce opinion."

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Windwheel concept combines tourist attraction with "silent turbine"

February 26, 2015 / / 0 Comments


 The Dutch Windwheel concept is designed to be part energy icon, part tourist attraction an...


Excerpt from gizmag.com
By Stu Robarts


The Dutch have long used windmills to harness wind energy. A new concept proposed for city of Rotterdam, however, is surely one of the most elaborate windmills ever conceived. The Dutch Windwheel is a huge circular wind energy converter that houses apartments, a hotel and a giant coaster ride.

The concept is designed to be part energy icon, part tourist attraction and part residential building. It is a 174-m (571-ft) structure comprising two huge rings that appear to lean against each other. "We wanted to combine a big attraction for Rotterdam with a state-of-the-art sustainable concept," explains Lennart Graaff of the Dutch Windwheel Corporation, to Gizmag.

The larger outer ring houses 40 pods on rails that move around the ring and provide those who visit with views of Rotterdam and its port. The smaller inner ring, meanwhile, houses 72 apartments, a 160-room hotel across seven floors and a panoramic restaurant and viewing gallery. Perhaps most remarkable feature of of all, however, is a huge "bladeless turbine" that spans the center smaller ring.

Although this may look and sound like some of the more out-there architectural concepts that Gizmag has featured, it is actually based on existing (albeit prototypical) technology. The electrostatic wind energy convertor (EWICON) was developed at Delft Technical University and generates electricity by harnessing the movement of charged water droplets in the wind. Its lack of moving parts makes it noiseless and easier to maintain than traditional turbines.

Dhiradj Djairam, of the TU Delft team that developed the EWICON, tells Gizmag that the Dutch Windwheel Corporation has expressed "a serious interest" in the technology. Djairam says he has provided an explanation of the technology to the organization and provided a rough outline for a realistic research and development program. To date, only small-scale research projects have been carried out, with additional funding opportunities being explored.

The Dutch Windwheel concept is 174 m (571 ft) tall and has underwater foundations

The Dutch Windwheel concept has other sustainable aspects, too. Photovoltaic thermal hybrid panels would be used to contribute to the generation of electricity, and rainwater would be collected for use in the building. The Dutch Windwheel Corporation says the building itself is designed to be built with locally-sourced materials, and in such a way as it could ultimately be disassembled and re-used elsewhere.

Among the other features of the design are space for commercial functions in the structure's plinth, and foundations that are underwater, making it it look as though the structure is floating. 

We're told that the amount of power the Dutch Windwheel will require to run – and be able to generate – is not yet clear. Likewise, the final technologies and additional sustainability features that would be present in the building have yet to be finalized...

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Let’s go back to the moon. No, Mars. No, the moon. The debate continues.

February 24, 2015 / / 0 Comments




Excerpt from washingtonpost.com
By Christian Davenport 

To the moon again? Or Mars?
The questions have hung over NASA for years, and emerged again at a Senate committee hearing Tuesday.

Under President George W. Bush, the target was the moon. Under Obama, who said “we’ve been there before,” Mars became the mission.

But now as his term nears its end, there is some increasingly vocal criticism of that decision, saying there isn’t the funding or political will to get to Mars.

Focusing on Mars is a “flawed policy direction,” Scott Pace, the director of the Space Policy Institute at George Washington University testified on Tuesday. The shift in goals “blindsided” the international space community, he said. The moon “is the next logical target for all of our potential international partners.”

Russia has endorsed sending astronauts there, he said. China sent an unmanned rover to the moon, and unveiled designs for a new heavy rocket for deep space exploration. It even has plans to build its own space station. “Growing space powers such as the Republic of Korea and India have their own unmanned lunar ambitions,” Pace said, while adding that the private sector has also made huge advancements.

To regain its prominence in space, the United States should “lead a multinational program to explore the moon," Pace said.

If it doesn’t, he could imagine a “post-American space world, with a full range of manned and unmanned space activities, but without American leadership or even, in many cases, an American presence.”

Testifying before the same committee, Buzz Aldrin, the Apollo 11 pilot who was the second man to walk on the moon, said NASA is right to focus on going beyond the moon. "American leadership is more than simply getting one step ahead of our global competitors," he said. "American leadership is inspiring the world by consistently doing what no other nation is capable of doing."

Aldrin said he's working on a plan to get to Mars, and the next president should press ahead with the mission.

“I believe that early in the next administration, the nation must commit to developing a permanent presence on Mars,” he said.
With much fanfare, NASA has trumpeted its “Journey to Mars” campaign. And it has highlighted the unmanned test flight of the Orion capsule last year as evidence of its progress toward reaching the Red Planet. It is also developing a new heavy rocket, known as the Space Launch System, designed to go to Mars and deep space.

But critics have maintained that without the funding to support such an endeavor, the attempt is a little more than a public relations stunt. And while Sen. Ted Cruz (R-Texas) and other members the committee on Tuesday said they were committed to the new rocket, others have been less supportive.

“We made a wrong decision when we went down this road,” Rep. Dana Rohrabacher (R-Calif.) said at a hearing late last year.

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‘Firefly’ Starship to Blaze a Trail to Alpha Centauri?

February 21, 2015 / / 0 Comments

The Icarus Interstellar 'Firefly' starship concept could use novel nuclear fusion techniques to power its way to Alpha Centauri within 100 years.Adrian MannExcerpt from news.discovery.com As part of Icarus Interstellar's continuing series ...

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NASA Wants to Send a Submarine to Titan’s Seas ~ Video

February 13, 2015 / / 0 Comments



Titan


Excerpt from news.discovery.com

In a sneak peek of a possible future mission to Saturn’s moon Titan, NASA has showcased their vision of a robotic submersible that could explore the moon’s vast lakes of liquid methane and ethane.

Studying Titan is thought to be looking back in time at an embryonic Earth, only a lot colder. Titan is the only moon in the solar system to have a significant atmosphere and this atmosphere is known to possess its own methane cycle, like Earth’s water cycle. Methane exists in a liquid state, raining down on a landscape laced with hydrocarbons, forming rivers, valleys and seas.

Several seas have been extensively studied by NASA’s Cassini spacecraft during multiple flybys, some of which average a few meters deep, whereas others have depths of over 200 meters (660 feet) — the maximum depth at which Cassini’s radar instrument can penetrate.


So, if scientists are to properly explore Titan, they must find a way to dive into these seas to reveal their secrets.

At this year’s Innovative Advanced Concepts (NIAC) Symposium, a Titan submarine concept was showcased by NASA Glenn’s COMPASS Team and researchers from Applied Research Lab.

Envisaged as a possible mission to Titan’s largest sea, Kracken Mare, the autonomous submersible would be designed to make a 90 day, 2,000 kilometer (1,250 mile) voyage exploring the depths of this vast and very alien marine environment. As it would spend long periods under the methane sea’s surface, it would have to be powered by a radioisotope generator; a source that converts the heat produced by radioactive pellets into electricity, much like missions that are currently exploring space, like Cassini and Mars rover Curiosity.

Communicating with Earth would not be possible when the vehicle is submerged, so it would need to make regular ascents to the surface to transmit science data.

But Kracken Mare is not a tranquil lake fit for gentle sailing — it is known to have choppy waves and there is evidence of tides, all contributing to the challenge. Many of the engineering challenges have already been encountered when designing terrestrial submarines — robotic and crewed — but as these seas will be extremely cold (estimated to be close to the freezing point of methane, 90 Kelvin or -298 degrees Fahrenheit), a special piston-driven propulsion system will need to be developed and a nitrogen will be needed as ballast, for example.

This study is just that, a study, but the possibility of sending a submersible robot to another world would be as unprecedented as it is awesome.

Although it’s not clear at this early stage what the mission science would focus on, it would be interesting to sample the chemicals at different depths of Kracken Mare.

“Measurement of the trace organic components of the sea, which perhaps may exhibit prebiotic chemical evolution, will be an important objective, and a benthic sampler (a robotic grabber to sample sediment) would acquire and analyze sediment from the seabed,” the authors write (PDF). “These measurements, and seafloor morphology via sidescan sonar, may shed light on the historical cycles of filling and drying of Titan’s seas. Models suggest Titan’s active hydrological cycle may cause the north part of Kraken to be ‘fresher’ (more methane-rich) than the south, and the submarine’s long traverse will explore these composition variations.”

A decade after the European Huygens probe landed on the surface of Titan imaging the moon’s eerily foggy atmosphere, there have been few plans to go back to this tantalizing world. It would be incredible if, in the next few decades, we could send a mission back to Titan to directly sample what is at the bottom of its seas, exploring a region where the molecules for life’s chemistry may be found in abundance.



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NASA probe snaps amazing image of Ceres

February 6, 2015 / / 0 Comments



    NASA's Dawn space probe has taken the sharpest-yet image of Ceres, a dwarf planet in our solar system's asteroid belt.

    Excerpt from SPACE.com

    By Mike Wall  

    NASA's Dawn spacecraft has taken the sharpest-ever photos of Ceres, just a month before slipping into orbit around the mysterious dwarf planet.

    Dawn captured the new Ceres images Wednesday (Feb. 4), when the probe was 90,000 miles (145,000 kilometers) from the dwarf planet, the largest object in the main asteroid belt between Mars and Jupiter.

    On the night of March 5, Dawn will become the first spacecraft ever to orbit Ceres — and the first to circle two different solar system bodies beyond Earth. (Dawn orbited the protoplanet Vesta, the asteroid belt's second-largest denizen, from July 2011 through September 2012.) 

    "It's very exciting," Dawn mission director and chief engineer Marc Rayman, who's based at NASA's Jet Propulsion Laboratory in Pasadena, California, said of Dawn's impending arrival at Ceres. "This is a truly unique world, something that we've never seen before."


    The 590-mile-wide (950 km) Ceres was discovered by Italian astronomer Giuseppe Piazzi in 1801. It's the only dwarf planet in the asteroid belt, and contains about 30 percent of the belt's total mass. (For what it's worth, Vesta harbors about 8 percent of the asteroid belt's mass.)

    Despite Ceres' proximity (relative to other dwarf planets such as Pluto and Eris, anyway), scientists don't know much about the rocky world. But they think it contains a great deal of water, mostly in the form of ice. Indeed, Ceres may be about 30 percent water by mass, Rayman said.

    Ceres could even harbor lakes or oceans of liquid water beneath its frigid surface. Furthermore, in early 2014, researchers analyzing data gathered by Europe's Herschel Space Observatory announced that they had spotted a tiny plume of water vapor emanating from Ceres. The detection raised the possibility that internal heat drives cryovolcanism on the dwarf planet, as it does on Saturn's moon's Enceladus. (It's also possible that the "geyser" was caused by a meteorite impact, which exposed subsurface ice that quickly sublimated into space, researchers said).

    The interior of Ceres may thus possess liquid water and an energy source — two key criteria required for life as we know it to exist.
    Dawn is not equipped to search for signs of life. But the probe — which is carrying a camera, a visible and infrared mapping spectrometer and a gamma ray and neutron spectrometer — will give scientists great up-close looks at Ceres' surface, which in turn could shed light on what's happening down below. 

    For example, Dawn may see chemical signs of interactions between subsurface water, if it exists, and the surface, Rayman said.
    "That's the sort of the thing we would be looking for — surface structures or features that show up in the camera's eye, or something about the composition that's detectable by one of our multiple spectrometers that could show evidence," he told Space.com. "But if the water doesn't make it to the surface, and isn't in large enough reservoirs to show up in the gravity data, then maybe we won't find it."

    Dawn will also attempt to spot Ceres' water-vapor plume, if it still exists, by watching for sunlight scattered off water molecules above the dwarf planet. But that's going to be a very tough observation to make, Rayman said.

    "The density of the water [observed by Herschel] is less than the density of air even above the International Space Station," he said. "For a spacecraft designed to map solid surfaces of airless bodies, that is an extremely difficult measurement." 

    Merging onto the freeway

    Dawn is powered by low-thrust, highly efficient ion engines, so its arrival at Ceres will not be a nail-biting affair featuring a make-or-break engine burn, as most other probes' orbital insertions are.

    Indeed, as of Friday (Feb. 6), Dawn is closing in on Ceres at just 215 mph (346 km/h), Rayman said —and that speed will keep decreasing every day.

    "You take a gentle, curving route, and then you slowly and safely merge onto the freeway, traveling at the same speed as your destination," Rayman said. "Ion propulsion follows that longer, more gentle, more graceful route."

    Dawn won't start studying Ceres as soon as it arrives. The spacecraft will gradually work its way down to its first science orbit, getting there on April 23. Dawn will then begin its intensive observations of Ceres, from a vantage point just 8,400 miles (13,500 km) above the dwarf planet's surface.

    The science work will continue — from a series of increasingly closer-in orbits, including a low-altitude mapping orbit just 230 miles (375 km) from Ceres' surface — through June 30, 2016, when the $466 million Dawn mission is scheduled to end.
    Rayman can't wait to see what Dawn discovers.

    "After looking through telescopes at Ceres for more than 200 years, I just think it's really going to be exciting to see what this exotic, alien world looks like," he said. "We're finally going to learn about this place."

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    Hubble Juiced! ~ CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble

    January 31, 2015 / / 0 Comments



    CU-Boulder to Design Space Telescope 1000 Times Sharper than Hubble
    The Hubble Space Telescope


    Excerpt from utahpeoplespost.com


    Researchers from the Department of Astrophysical and Planetary Sciences at the University of Colorado Boulder are currently working on an improved version of space telescope that could provide space images nearly 1,000 times sharper than those provided by long-running Hubble.

    The new space telescope, dubbed the Aragoscope, is named after a French astronomer called Francois Arago. The new telescope is exclusively designed by the CU- Boulder scientists and involves a brand new technology developed by the university. According to its designers, the space optical instrument would be lighter, slimmer, and sharper than Hubble.

    Additionally, the Aragoscope will involve several independent pieces that can be later assembled in space. So, the launching costs of these smaller building blocks will be significantly reduced.
    Traditionally, space telescopes have essentially been monolithic pieces of glass like the Hubble Space Telescope. But the heavier the space telescope, the more expensive the cost of the launch,”
    said Anthony Harness, one of the researchers involved in the project and doctoral student at the CU-Boulder.

    However, the new instrument will not replace Hubble, which is scheduled to be shut down in 5 years time. Last year, Hubble had its fifth and final maintenance service, and it was still in a pretty good shape although one of its six gyroscopes couldn’t be stabilized. Despite Hubble has been operating since 1990, NASA engineers hope that it will make it to its 30th anniversary.

    If Hubble remains operational, NASA plans to use it along with its successor, the James Webb Space Telescope, which is scheduled to be launched in October 2018. Astronomers hope that the two space telescopes, which use two different imaging methods, would help them better understand the origins and early evolution of the universe.

    But the UC-Boulder team claim that their new space telescope would surpass Hubble with its enhanced capacity of spotting distant Earth-like planets in the depths of a remote universe...

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    New Telescope in Chile Now Searching for Alien Planets

    January 26, 2015 / / 0 Comments

    The NGTS telescopes operating at ESO Paranal, Chile (Credit: ESO/ G. Lambert)


    Excerpt from  space.com

    A new alien-planet–hunting telescope has just come online in Chile, and it could help scientists peer into the atmospheres of relatively small planets circling nearby stars.

    The Next-Generation Transit Survey (NGTS for short) — located at the European Southern Observatory's (ESO) Paranal Observatory — is designed to seek out planets two to eight times the diameter of Earth as they pass in front of their stars. Such a planet will cause the light of the star to dip ever so slightly when passing in front of it, allowing the telescope to detect the planet during its transit.

    "We are excited to begin our search for small planets around nearby stars," Peter Wheatley, an NGTS project lead from the University of Warwick, U.K., said in as statement. "The NGTS discoveries, and follow-up observations by telescopes on the ground and in space, will be important steps in our quest to study the atmospheres and composition of small planets such as the Earth."
    The instrument is designed to measure the brightness of stars more accurately than any other ground-based wide-field survey, ESO officials said. The NGTS is made up of 12 telescopes that will operate robotically, according to ESO. Astronomers using the survey hope to find small, bright planets in order to learn more about the densities of them.

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    The Best Bet for Alien Life May Be in Planetary Systems Very Different From Ours

    January 16, 2015 / / 0 Comments




    Excerpt from wired.com


    In the hunt for extraterrestrial life, scientists started by searching for a world orbiting a star just like the sun. After all, the steady warmth of that glowing yellow ball in the sky makes life on Earth possible.

    But as astronomers continue to discover thousands of planets, they’re realizing that if (or when) we find signs of extraterrestrial life, chances are good that those aliens will orbit a star quite different from the sun—one that’s redder, cooler, and at a fraction of the sun’s size and mass. So in the quest for otherworldly life, many astronomers have set their sights on these small stars, known as red dwarfs or M dwarfs.

    At first, planet-hunting astronomers didn’t care so much about M dwarfs. After the first planet outside the solar system was discovered in 1995, scientists began hunting for a true Earth twin: a rocky planet like Earth with an orbit like ours around a sun-like star. Indeed, the search for that kind of system drove astronomers through most of the 2000s, says astronomer Phil Muirhead of Boston University.

    But then astronomers realized that it might be technically easier to find planets around M dwarfs. Detecting another planet is really hard, and scientists rely on two main methods. In the first, they look for a drop in a star’s brightness when a planet passes in front of it. In the second, astronomers measure the slight wobble of a star, caused by the gentle gravitational tug of an orbiting planet. With both of these techniques, the signal is stronger and easier to detect for a planet orbiting an M dwarf. A planet around an M dwarf also orbits more frequently, increasing the chances that astronomers will spot it.

    M dwarfs got a big boost from the Kepler space telescope, which launched in 2008. By staring at small patch of the sky, the telescope searches for suddenly dimming stars when a planet passes in front of them. In doing so, the spacecraft discovered a glut of planets—more than 1,000 at the latest count—it found a lot of planets around M dwarfs. “Kepler changed everything,” Muirhead said. Because M-dwarf systems are easier to find, the bounty of such planets is at least partly due to a selection effect. But, as Muirhead points out, Kepler is also designed to find Earth-sized planets around sun-like stars, and the numbers so far suggest that M-dwarfs may offer the best odds for finding life.

    “By sheer luck you would be more likely to find a potentially habitable planet around an M dwarf than a star like the sun,” said astronomer Courtney Dressing of Harvard. She led an analysis to estimate how many Earth-sized planets—which she defined as those with radii ranging from one to one-and-a-half times Earth’s radius—orbit M dwarfs in the habitable zone, the region around the star where liquid water can exist on the planet’s surface. According to her latest calculations, one in four M dwarfs hosts such a planet.

    That’s higher than the estimated number of Earth-sized planets around a sun-like star, she says. For example, an analysis by astronomer Erik Petigura of UC Berkeley suggests that fewer than 10 percent of sun-like stars have a planet with a radius between one and two times that of Earth’s.

    This illustration shows Kepler-186f, the first rocky planet found in a star's habitable zone. Its star is an M dwarf.
    This illustration shows Kepler-186f, the first rocky planet found in a star’s habitable zone. Its star is an M dwarf. NASA Ames/SETI Institute/JPL-Caltech


    M dwarfs have another thing going for them. They’re the most common star in the galaxy, comprising an estimated 75 percent of the Milky Way’s hundreds of billions of stars. If Dressing’s estimates are right, then our galaxy could be teeming with 100 billion Earth-sized planets in their stars’ habitable zones.

    To be sure, these estimates have lots of limitations. They depend on what you mean by the habitable zone, which isn’t well defined. Generally, the habitable zone is where it’s not too hot or too cold for liquid water to exist. But there are countless considerations, such as how well a planet’s atmosphere can retain water. With a more generous definition that widens the habitable zone, Petigura’s numbers for Earth-sized planets around a sun-like star go up to 22 percent or more. Likewise, Dressing’s numbers could also go up.
    Astronomers were initially skeptical of M-dwarf systems because they thought a planet couldn’t be habitable near this kind of star. For one, M dwarfs are more active, especially during within the first billion years of its life. They may bombard a planet with life-killing ultraviolet radiation. They can spew powerful stellar flares that would strip a planet of its atmosphere.

    And because a planet will tend to orbit close to an M dwarf, the star’s gravity can alter the planet’s rotation around its axis. When such a planet is tidally locked, as such a scenario is called, part of the planet may see eternal daylight while another part sees eternal night. The bright side would be fried while the dark side would freeze—hardly a hospitable situation for life.

    But none of these are settled issues, and some studies suggest they may not be as big of a problem as previously thought, says astronomer Aomawa Shields of UCLA. For example, habitability may depend on specific types and frequency of flares, which aren’t well understood yet. Computer models have also shown that an atmosphere can help distribute heat, preventing the dark side of a planet from freezing over.

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    Chinese space program achieves lunar milestone

    January 12, 2015 / / 0 Comments

    Excerpt from csmonitor.comA Chinese spacecraft service module has entered orbit around the moon, months after being used in the country's landmark test flight that sent a prototype sample-return capsule on a flight around the moon and returned it to...

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    Alien Earths are out there: Our home world is not ‘unique’ ‘Recipe for habitable planets’ issued by Harvard

    January 7, 2015 / / 0 Comments


     



    Excerpt from theregister.co.uk

    New research suggests planets similar to Earth are much more common across the galaxy than previously thought.

    And the boffins behind this revelation have also come up with a simple chemical recipe for creating habitable worlds suitable for use by advanced super-powered intelligences and/or deities etc.
    "Our solar system is not as unique as we might have thought," says Courtney Dressing, graduate student at the Harvard-Smithsonian Center for Astrophysics.

    Ms Dressing bases this assertion on data from the HARPS-North (High-Accuracy Radial velocity Planet Searcher, Northern) instrument on the 3.6-metre Telescopio Nazionale Galileo in the Canary Islands. This is designed to accurately measure the masses of small, Earthish-sized worlds. Once you have mass and volume, as any fule kno, you have density and thus a fair notion of what a given alien world is made of - and this tells you whether it can be much like Earth.


    So chuffed are the Harvard boffins with this discovery that they've come up with a handy "recipe" for cooking up a world with Earth-esque life on it, thus:
    1 cup magnesium
    1 cup silicon
    2 cups iron
    2 cups oxygen
    ½ teaspoon aluminum
    ½ teaspoon nickel
    ½ teaspoon calcium
    ¼ teaspoon sulfur
    dash of water delivered by asteroids
     Blend well in a large bowl, shape into a round ball with your hands and place it neatly in a habitable zone area around a young star. Do not over mix. Heat until mixture becomes a white hot glowing ball. Bake for a few million years. Cool until color changes from white to yellow to red and a golden-brown crust forms. It should not give off light anymore. Season with a dash of water and organic compounds. It will shrink a bit as steam escapes and clouds and oceans form. Stand back and wait a few more million years to see what happens.

    If you are lucky, a thin frosting of life may appear on the surface of your new world.

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