Universe Today

June 19, 2014December 23, 2015 by Elizabeth Howell

See This Orange Smudge? This Could Be NASA’s Target For The Asteroid Mission

An image of asteroid 2011 MD -- a candidate for a potential future mission to an asteroid -- taken by NASA's Spitzer Space Telescope in February 2014. The exposure took 20 hours to accomplish and was done in infrared light. Credit: NASA

In the center of the image above is an orange smudge. It may not look like much to the untrained eye, but to NASA it represents potential. It’s a candidate asteroid target for a mission the agency badly wants to happen, even though nobody knows for sure yet if things will line up for humans to visit there one day.

This is a picture of asteroid 2011 MD taken by NASA’s Spitzer Space Telescope. It’s about 6 meters (20 feet) across and appears to have a low density, the agency said in a statement. While NASA is still looking for other candidates for its asteroid initiative, the agency added this would be the sort of asteroid it’s looking to visit.

“The asteroid appears to have a structure perhaps resembling a pile of rocks, or a ‘rubble pile.’Since solid rock is about three times as dense as water, this suggests about two-thirds of the asteroid must be empty space,” NASA stated in this press release.

“The research team behind the observation says the asteroid could be a collection of small rocks, held loosely together by gravity, or it may be one solid rock with a surrounding halo of small particles.”

Artist's conception of the structure around 2011 MD, a candidate asteroid for NASA's proposed asteroid redirect mission. Credit: NASA/JPL-Caltech — Artist’s conception of the structure around 2011 MD, a candidate asteroid for NASA’s proposed asteroid redirect mission. Credit: NASA/JPL-Caltech

You can read more about this asteroid in Astrophysical Journal Letters. There was another study done on 2011 MD earlier this year that was also in ApJL, or in preprint version in Arxiv.

Announcing this asteroid candidate was just one of several things NASA made public today. It added that it plans to send off an ARM (Asteroid Redirect Mission) robotic spacecraft in 2019, and about one year before that it will decide which asteroid to send this spacecraft to.

NASA has two concept ideas for ARM, and it’s planning to award $4.9 million (it had initially planned for up to $6 million) for others to make more detailed investigations into which is the more feasible. Read the full list of recipients at this NASA website.

One idea is to pick up a small asteroid, and the other is to carve off a small portion of a bigger asteroid. Whatever the choice, it would involve coming up with an object that is less than 32 feet (10 meters) across to move to the moon’s orbit. NASA will decide what to do later this year.

“The studies will be completed over a six-month period beginning in July, during which time system concepts and key technologies needed for ARM will be refined and matured. The studies also will include an assessment of the feasibility of potential commercial partners to support the robotic mission,” NASA stated.

An astronaut retrieves a sample from an asteroid in this artist's conception. Credit: NASA — An astronaut retrieves a sample from an asteroid in this artist’s conception. Credit: NASA

Also, some more details about other candidates: NASA has found nine so far that it deems suitable, and size estimates have been made on three of those nine candidates. A fourth, 2008 HU4, will be close to Earth in 2016 and allow for “interplanetary radar” to learn more about its size and rotation, NASA said. The other ones will not get close enough to Earth for a better look before the mission selection is done.

NASA added that it expects to add more through its Near-Earth Object program, as one to two asteroids get close enough to our planet every year for analysis. Further, the agency hopes to learn more about asteroid makeup through its planned Origins-Spectral Interpretation-Resource Identification-Security-Regolith Explorer (OSIRIS-REx) mission, which is on its way to asteroid Bennu in 2018 after a launch in 2016.

All of this, of course, is dependent on NASA’s budgetary situation for the years to come, which in turn depends on support in Congress.

June 19, 2014December 23, 2015 by Elizabeth Howell

Poof! Mountain Blows Its Top To Make Way For Huge Telescope

The top of Cerro Armazones in Chile is blown off June 19, 2014 for the European Extremely Large Telescope. Credit: Vine / ObservingSpace

All’s clear for a huge telescope to start construction on a mountaintop in Chile! That puff you see is the top of Cerro Armazones getting a haircut, losing many tons of rock in just a few seconds. The aim is to clear the way for the European Extremely Large Telescope, a 39-meter (128-foot) monster of a telescope to occupy the mountain’s top. Once completed later this decade, the optical/near-infrared telescope has an ambitious research schedule ahead of it. It will search for planets that look like Earth, try to learn more about how nearby galaxies were formed, and even look for the mysterious dark energy and dark matter that pervade our universe. Construction is being overseen by the European Southern Observatory, which provided an enthusiastic livetweet of the process. You can learn more about E-ELT on ESO’s webpage here. Thanks to @observingspace for posting a Vine of the explosion. Below is an ESO video showing preparations for the blast.

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The E-ELT will gather 8 000 000 times more than Galileo’s telescope #EELTblast Credit @ESO http://t.co/Y3FSz0jBV2 — ESO (@ESO) June 19, 2014

The E-ELT will gather 100.000.000 times more light than the human eye #EELTblast Credit: @ESO http://t.co/Wmb6ZGORZX— ESO (@ESO) June 19, 2014

#EELTblast wasn’t a big boom from Paranal, but its significance is Earth-shattering. Thank you for being part of it! Close-up views coming — ESO (@ESO) June 19, 2014

June 19, 2014December 23, 2015 by Nancy Atkinson

Video: SpaceX Tests New Steerable ‘Fins’ on the Falcon 9R

Screenshot of a June 2014 F9R test flight.

Well, this is cool: A new video from SpaceX shows the Falcon 9 Reusable (F9R) rocket during a 1,000 meter test flight at the SpaceX facility in McGregor, Texas. This was the first flight test of a set of steerable fins that provide control of the rocket during the fly-back portion of the return flight. The fins deploy approximately 1:15 into the test flight and return to their original locked position just prior to landing.

This seems like a truly smooth flight!

These types of fins are not new, but are new for human space flight. They’ve been used on missiles and bombs to aid in precision targeting, and likewise will help the F9R to land precisely on target.

SpaceX confirmed that during the early tests flights of F9R, the landing legs will be fixed in the down position, however soon they will transition to a liftoff with the legs stowed against the side of the rocket with the legs extending just before landing. The company also said that future test flights of F9R will be at SpaceX’s New Mexico facility which will allow them to test in higher altitude flights, give them the chance to prove unpowered guidance and to prove out landing cases that are “more flight-like.”

June 19, 2014December 23, 2015 by Elizabeth Howell

What Will Rosetta’s Comet Look Like? How Artists Over The Years Pictured It

Artist's impression (from 2002) of the Philae lander on Comet 67P/Churyumov-Gerasimenko. Credit: ESA / AOES Medialab

Comets are notoriously hard to predict — just ask those people on Comet ISON watch late in 2013. So as Rosetta approaches its cometary target, no one really knows what the comet will look like from up close. Yes, there are pictures of other cometary nuclei (most famously, Halley’s Comet) but this one could look completely different.

Several artists have taken a stab at imagining what Rosetta will see when it gets close to the comet in August, and what Philae will touch on when it reaches the surface in November. You can see their work throughout this article.

Meanwhile, the European Space Agency just issued an update on what they can see of 67P/Churyumov–Gerasimenko from half a million km away — the comet is quieter, they said.

“Strikingly, there is no longer any sign of the extended dust cloud that was seen developing around nucleus at the end of April and into May,” ESA stated in a press release. “Indeed, monitoring of the comet has shown a significant drop in its brightness since then.”

Artist's impression (from 2002) of Rosetta orbiting Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab — Artist’s impression (from 2002) of Rosetta orbiting Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab

This variability is common in comets, but it’s the first time it’s been seen from so close, ESA said. Comets warm up as they approach the sun, releasing ice, gas and dust that form a swarm of material.

“As comets are non-spherical and lumpy, this process is often unpredictable, with activity waxing and waning as they warm. The observations made over the six weeks from the end of April to early June show just how quickly the conditions at a comet can change,” ESA added.

For more about Philae’s landing, check out this past article from Universe Today.

Rosetta flies above the Philae lander on Comet 67P/Churyumov-Gerasimenko in this artist's impression from 2002. Credit: Astrium - E. Viktor — Rosetta flies above the Philae lander on Comet 67P/Churyumov-Gerasimenko in this artist’s impression from 2002. Credit: Astrium – E. Viktor

Artist's impression (from 2002) of the Philae lander during descent on Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab — Artist’s impression (from 2002) of the Philae lander during descent on Comet 67P/Churyumov-Gerasimenko. Credit: ESA, image by AOES Medialab

Rosetta flies above Comet 67P/Churyumov–Gerasimenko in this 2013 artist's impression. Credit: ESA–C. Carreau/ATG medialab — Rosetta flies above Comet 67P/Churyumov–Gerasimenko in this 2013 artist’s impression. Credit: ESA–C. Carreau/ATG medialab

Artist's impression (from 2013) of the Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko. Credit: ESA/ATG medialab — Artist’s impression (from 2013) of the Philae lander on the surface of Comet 67P/Churyumov-Gerasimenko. Credit: ESA/ATG medialab

June 19, 2014December 23, 2015 by Nancy Atkinson

Watch Live: 180th Spacewalk for the International Space Station

Screenshot from NASA TV of today's spacewalk. Cosmonaut Oleg Artemyev is waving for the camera.

Broadcast live streaming video on Ustream

Cosmonauts Alexander Skvortsov and Oleg Artemyev are working outside at the International Space Station today! They will spend about 6.5 hours outside installing an antenna for data relays, relocating a cargo boom, swabbing samples from a window on the Zvezda service module and switching out science experiment gear. Watch live above.

This is milestone of sorts for ISS spacewalks: it is the 180th spacewalk in support of space station construction and maintenance since December 1998, when the Russian Zarya module was mated to the US Unity node. You can read what that first spacewalk was like in an interview with astronauts Bob Cabana: What Day 1 on the International Space Station Was like for the Astronauts.

And what’s going on inside the ISS today?

Pretty neat up here right now- two Russian crew mates are spacewalking but business as usual for me and @astro_alex

— Reid Wiseman (@astro_reid) June 19, 2014

If you want to know who is who during the spacewalk, Skvortsov is wearing the Russian Orlan spacesuit with red stripes, and Artemyev’s has a spacesuit with blue stripes.

June 18, 2014December 23, 2015 by Nancy Atkinson

Space Vine: Moonlight Cruise over the Pacific at 28,000 kph

Screencap from a Vine video from Reid Wiseman on the International Space Station.

Oh, man you’re killin’ me Reid! Astronaut Reid Wiseman has been flooding the Twitter-waves with photos and news from the International Space Station, (you really need to check out his feed if you haven’t yet) and he’s also doing that crazy Vine video thing too. (In fact he did the first Vine from space earlier this month). This one is just awesomely beautiful.

June 18, 2014April 8, 2018 by Nancy Atkinson

Wow! See the ‘International Earth & Sky Photo Contest’ Winners

A montage of Earth & Sky International Photo Contest winners, courtesy of TWAN.

Need a little eye candy? Look no further! Here are the latest winners of the International Earth and Sky Photo Contest. This was the 5th annual contest, which is organized by The World at Night (TWAN), the National Optical Astronomy Observatory, and Global Astronomy Month from Astronomers Without Borders. This contest stresses the importance and awareness of dark skies, look for images that portray the “TWAN style” —showing both the Earth and the sky—by combining elements of the night sky set in the backdrop of the Earth horizon, often with a notable scenery or landmark.

The 2014 contest had two categories: “Beauty of The Night Sky” and “Against The Lights.”

“Both contest categories provide a visual awareness of the disappearing starry night sky and hopefully an understanding as to its cause,”said contest judge Connie Walker, associate scientist and education specialist at the National Optical Astronomy Observatory. “The added hope is that the photos will provide an incentive to be more actively involved in reasonable light pollution solutions and therefore dark skies preservation.”

Click on each of the image here for larger versions.

The first prize in Beauty of the Night Sky category was awarded to Luc Perrot from Réunion Island of France (southern Indian Ocean), for his image “Over the Top,” below, shot on Feb 28, 2014. A volcano in the Reunion Island peaks out of a sea of clouds and rests under stars.

“The photograph beautifully captures a scene that is eternal, the central bulge of the Milky Way is rising majestically over Piton de la Fournaise volcano,” said contest judge David Malin, who is widely known as a pioneer in scientific astrophotography “The image shows no sign of human presence, and is a reminder that the foreground landscape and the dark dust lanes in the Milky Way are made of the same elements, seen here as delicate clouds and solid mountain peaks.”

Here are the “Beauty of the Night Sky” top winners:

1- Luc Perrot, Reunion Island (France)
2- Ben Coffman, USA
3- Nicholas Roemmelt, Austria
4- Ibrahim Elawadi, Egypt
5- Phil Hart, Australia

We loved this image, below, from Nicholas Roemmelt of Austria for his outstanding capture of aurora over Kirkjufell waterfalls in Iceland in a moonlit night of March 2014, titled “Kirkjufell Nights” which won third place in the “Beauty of the Night” category.

Contest judge and long-time National Geographic photographer James Richardson regards this image “a fantastic confluence of the forces of nature. This is, of course, just one small corner of our universe, and yet we see swirling all the waterfalls carving at the rocky landscape, the mountain resisting erosion, the aurora sweeping around the pole and the stars beyond, part of the whole. The organizational power of this photograph is just wonderful.”

The first prize in “Against the Lights category” (and the overall contest winner) goes to Giorgia Hofer of Italy for his photo “Light in the Sky” taken on January 1, 2014 from Cibiana Pass in the Dolomites (Alps), northern Italy.

“I tried to portray the mist produced by the drones launched fireworks on the evening of new that were illuminated by a nearby light tower. in the only dark part of the sky the Big Dipper (the prominent part of constellation Ursa Major) is perfectly framed by the rays,” said the photographer.

Contest judge James Richardson said of this photo, “This captures the great ambiguity we feel about the night and night lighting. It is at once beautiful and beautifully composed. But it is also night lighting obscuring the beauties of the night. A beautiful image that confronts us with our own, conflicted desires.”

The entire “Against the Lights” winners are:
1- Giorgia Hofer, Italy
2- Alex Conu, Romania
3- Majid Ghohrudi, Iran
4- Mark Gee, New Zealand
5- Song Hongxiao, China

We also loved the fifth place winner in the “Against the Lights” category. “Heavenly Street” by Song Hongxiao of China is a long-exposure photo sequence of March 30, 2013 that captures star trails from the sacred Taishan or Mount Tai. Says the photographer: “Its been an ancient China tradition that people climb to the top of Mountain Tai to watch the beautiful sunrise and pray. In this picture thousands of people are walking across the Heavenly Street. The lights from their flashlight interplays with the stars in the sky.”

There are also 70 images as honorable mention which you can see in the video below, or in the contest Guest Gallery. The images were submitted (or taken) from 55 countries and territories.

You can find out more about this contest and the judges here. Keep your eye out for the chance to participate in next year’s contest at TWAN’s contest page.

June 18, 2014December 23, 2015 by Jason Major

Mercury’s Hot Flow Revealed by MESSENGER

A hot flow anomaly, or HFA, has been identified around Mercury (Credit: NASA/Duberstein)

Our Sun is constantly sending a hot stream of charged atomic particles out into space in all directions. Pouring out from holes in the Sun’s corona, this solar wind flows through the Solar System at speeds of over 400 km/s (that’s 893,000 mph). When it encounters magnetic fields, like those generated by planets, the flow of particles is deflected into a bow shock — but not necessarily in a uniform fashion. Turbulence can occur just like in air flows on Earth, and “space weather” results.

One of the more curious effects is a regional reversal of the flow of solar wind particles. Called a “hot flow anomaly,” or HFA, these energetic phenomena occur almost daily in Earth’s magnetic field, as well as on Jupiter and Saturn, and even on Mars and Venus where the magnetic fields are weak (but there are still planets blocking the stream of charged particles.)

Not to be left out in the cold, Mercury is now known to display HFAs, which have been detected for the first time by the MESSENGER spacecraft.

A NASA news release describes how the HFAs were confirmed:

The first measurement was of magnetic fields that can be used to detect giant electric current sheets that lead to HFAs. The second was of the heating of the charged particles. The scientists then analyzed this information to quantify what kind of turbulence exists in the region, which provided the final smoking gun of an HFA.

“Planets have a bow shock the same way a supersonic jet does,” explains Vadim Uritsky at NASA’s Goddard Space Flight Center. “These hot flow anomalies are made of very hot solar wind deflected off the bow shock.”

The different colors in this MESSENGER image of Mercury indicate the chemical, mineralogical, and physical differences between the rocks that make up the planet’s surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington. — Enhanced-color image of Mercury indicating the chemical and physical differences across its surface. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington.

The solar wind is not 100% uniform; it has discontinuities within its own complex magnetic fields. When these shifting fields pile up against a planet’s bow shock they can create turbulence patterns that trap hot plasma, which in turn produces its own magnetic fields. The shockwaves, heat, and energy produced are powerful enough to actually reverse the flow of the solar wind within the HFA bulge.

And the word “hot” is putting it lightly — plasma temperatures in an HFA can reach 10 million degrees.

Mercury may be only a little larger than our Moon but it does possess an internally-generated dipolar magnetic field, unlike the Moon, Venus, and Mars which have only localized or shallow fields. The confirmed presence of HFAs on Mercury indicates that they may be a feature in all planetary bow shocks, regardless of how their magnetic fields — if any — are produced.

The team’s results were published in the February 2014 issue of the Journal of Geophysical Research: Space Physics.

___________________

In related news, on June 17 MESSENGER successfully completed the first orbit adjustment maneuver to prepare it for its new — and final — low-altitude campaign, during which it will obtain its highest-resolution images ever of the planet’s surface and perform detailed investigations of its composition and magnetic field. Read more on the MESSENGER site here.

Source: NASA

June 18, 2014December 23, 2015 by Elizabeth Howell

Elon Musk: ‘I’m Hopeful That The First People Can Be Taken To Mars in 10, 12 Years’

SpaceX founder and CEO Elon Musk briefs reporters including Universe Today in Cocoa Beach, FL prior to SpaceX Falcon 9 rocket blastoff with SES-8 communications satellite on Dec 3, 2013 from Cape Canaveral, FL. Credit: Ken Kremer/kenkremer.com

Elon Musk, CEO of SpaceX, is a hot topic in the media these days. He recently unveiled a manned version of his successful Dragon spacecraft. He’s talking about retrieving the first stage of his Falcon 9 rocket, a feat that has never been accomplished.

Last night (June 18), Musk spoke on CNBC because his company was named #1 to the cable network’s second annual Disrupter 50 list. You can watch portions of the interview here and we’ve isolated the space-related parts below based on the transcript from CNBC (which does not exactly match Musk’s words, but is pretty close.)

And Musk is still a big fan of Mars exploration, as he says in the interview he hopes to see people walk on the planet in 10-12 years.

On attempting to recover the first stage of the Falcon 9 rocket that will launch six Orbcomm satellites on Friday, if the weather holds (it is only 30% go according to local news reports):

Essentially what I was alluding to a moment ago was is to be able to recover the rocket booster and then refly it. That’s the revolutionary potential. Now we have been trying to do that for 12 years, and haven’t yet succeeded. But I feel as though we are finally close to achieving it. We have a shot with the next launch of recovering the rocket booster. If not with this launch, I think a very good chance later this year, and then potentially to refly the booster next year. This would really mark a significant change in the technology of rocketry.

'Threading the needle', the Falcon 9/Dragon vehicle passes through the catenary lightning wires as it roars from the pad on the CRS-3 mission. Credit: nasatech.net — ‘Threading the needle’, the Falcon 9/Dragon vehicle passes through the catenary lightning wires as it roars from the pad on the CRS-3 mission. Credit: nasatech.net

Musck also spoke on what would happen if SpaceX does not get the next round of commercial crew funding from NASA. The company is right now being funded along with Boeing (CST-100) and Sierra Nevada (Dream Chaser), but NASA is still figuring out how many companies it can afford to back in the next stage, which will be announced later this year. Musk revealed the manned prototype version of its Dragon spacecraft to great media fanfare in late May.

First of all, I should acknowledge the critical role NASA played in the success of SpaceX. We wouldn’t be are where we are without the help of NASA. And it’s possible we may not win the commercial crew contract. We certainly have done that we can for our part. And I think we have got a great design solution. If NASA in the end doesn’t go with us, because also we are competing with big established companies like Boeing, then we’ll do our best to continue on our own with our own money. […]

Well it definitely would slow us down, but we would keep going and we should keep launching commercial satellites. We have an existing contract to transfer…from the space station so we would keep going. It just would be slower.

Elon Musk seated inside Dragon V2 explaining consoles at unveiling on May 29, 2014. Credit: SpaceX

Musk on how quickly he wants to see humans on Mars:

This is a very difficult thing, obviously. I’m hopeful that the first people could be taken to Mars in 10, 12 years. I think it’s certainly possible for that to occur. The thing that matters long term is to have a self-sustaining city on Mars. To make life multi-planetary. That will define a fundamental bifurcation of the future of human civilization. We’ll either be a multi-planet species and out there among the stars, or a single-planet species until some eventual extinction event, natural or man-made.

Why it’s difficult to get public funding right now:

The incentive structure tends to be short-term. You can trace it back to people that own the stocks, portfolio managers. They are evaluated on a quarterly basis, or at least an annual basis. They push companies to produce results on a quarterly or annual basis. With SpaceX we are trying to develop technology that will ultimately be able to take large numbers of people to Mars. That’s really difficult to get portfolio managers. It’s beyond their tenure in owning the stock. So it is difficult to ask them to like that.

The SpaceX Dragon capsule on approach to the ISS during the COTS 2 mission. Credit: NASA.

Which is harder, getting people to Mars or building a car battery that costs less than $5,000 (which is an oblique reference to Musk’s Tesla line of vehicles):

I think, probably, Mars. The car battery certainly is hard. I’m quite optimistic, though, about improvements in the battery price or the cost of the battery. The fundamental cost. We have daily meetings with Panasonic, our key development partner, on this. I am really feeling quite good about being able to produce a compelling mass market car in about three years.

What would be a “truly disruptive” technology:

I mean, at this point, human life span is mostly about old age. It’s not about cancer or anything else. If you cured cancer, I think the average life expectancy would increase from two years. You would go from 80 to 82, or something like that. We just have a genetic life span. It’s kind of like if you take a fruit fly and gave it the best exercise and diet possible, the perfect life. Maybe it will live four weeks instead of three weeks. Genetics just drives a lot of these things. So for something to be truly disruptive on that front, you would want to do something with genetics. I don’t have much involvement there. Or any involvement, really.

June 18, 2014December 23, 2015 by Elizabeth Howell

Watch A Mountaintop Blow Up Live For Astronomy Tomorrow

Artist's conception of the E-ELT (left) and Very Large Telescope compared with the Giza Pyramids. Credit: ESO

While we space geeks are lucky enough to watch rocket launches regularly, it’s not often we get to see a mountain top being blown off for the sake of astronomy!

Tomorrow, the European Southern Observatory plans an event centered on a blast on Cerro Armazones, a 3,060-meter (10,000-foot) mountain in Chile’s Atacama Desert. The goal is to make way for construction of the European Extremely Large Telescope, which as its name implies will be a monster of an observatory. Read below for details on how to watch live.

“The E-ELT will tackle the biggest scientific challenges of our time, and aim for a number of notable firsts, including tracking down Earth-like planets around other stars in the ‘habitable zones’ where life could exist — one of the Holy Grails of modern observational astronomy,” ESO states on its page about the 39-meter (128-foot) optical/near-infrared telescope.

The set-up crew for the E-ELT blast looks at Cerro Armazones. Credit: ESO

“It will also perform ‘stellar archaeology’ in nearby galaxies, as well as make fundamental contributions to cosmology by measuring the properties of the first stars and galaxies and probing the nature of dark matter and dark energy.”

We’re sure astronomers can hardly wait for operations to start in the next decade or so. ESO will livetweet the event (also follow the hashtag #EELTblast, where you can ask questions) and watch the entire event live tomorrow here, starting around 12:30 p.m. EDT (4:30 p.m. UTC).

In related news, the last of the Atacama Large Millimeter/submillimeter Array’s (ALMA’s) 66 antennas recently arrived at the ALMA site, which is 5,000 meters (16,400 feet) high on the Chajnantor Plateau in the Atacama Desert of northern Chile. This ESO telescope was officially inaugurated last year.

For more information about the E-ELT, consult this ESO webpage.