The Search For Life On Europa Could Center On Celestial Party-Crashers

Jupiter's moon, Europa, appears to have clay-like minerals on it (visible in blue in the false-color patch, amid red-colored water ice). The information came from new data analysis from NASA's Galileo mission, which concluded in 2003. The backdrop is a mosaic of visual-light images from Galileo's Near-Infrared Mapping Spectrometer. Credit: NASA/JPL-Caltech/SETI

The cool thing about space missions is long after they conclude, the data can yield the most interesting information. Here’s an example: Jupiter’s moon Europa may have a ripe spot for organic materials to take root.

Scouring the data from NASA’s past Galileo mission — which ended a decade ago — scientists unveiled an area with “clay-like minerals” on it that came to be after an asteroid or comet smashed into the surface. The connection? These celestial party-crashers often carry organics with them.

“Organic materials, which are important building blocks for life, are often found in comets and primitive asteroids,” stated Jim Shirley, a research scientist at NASA’s Jet Propulsion Laboratory. “Finding the rocky residues of this comet crash on Europa’s surface may open up a new chapter in the story of the search for life on Europa.”

Reprocessed Galileo image of Europa's frozen surface by Ted Stryk (NASA/JPL/Ted Stryk)
Reprocessed Galileo image of Europa’s frozen surface by Ted Stryk (NASA/JPL/Ted Stryk)

Europa is considered one of the best spots in our solar system to look for life, due to the ocean lurking beneath its icy surface, surface salts that can provide energy, and a source of heat as the mighty Jupiter squeezes and releases the moon like a tennis ball.

The minerals (called phyllosilicates) emerged after Shirley’s team ran a new analysis on infrared pictures snapped by Galileo in 1998, basically working to refine the signal out of the images (which are much lower quality than what we are capable of today).

After the analysis, the phyllosilicates appeared in a “broken ring”, NASA stated, about 75 miles (120 kilometers) away from a crater site. The crater itself is about 20 miles (30 kilometers) in diameter. Scientists are betting that the ring of phyllosilicates is debris (“splash back of material”, NASA says), after a celestial body struck at or around a 45 degree angle from vertical. It’s unlikely the phyllosilicates came from Europa’s ocean given the crust, which can be as thick as 60 miles (100 kilometers).

Europa Report was a 2013 film that focused on a human mission to the Jovian moon. Poster by Start Motion Pictures.
Europa Report was a 2013 film that focused on a human mission to the Jovian moon. Poster by Start Motion Pictures.

“If the body was an asteroid, it was likely about 3,600 feet (1,100 meters) in diameter. If the body was a comet, it was likely about 5,600 feet (1,700 meters) in diameter. It would have been nearly the same size as the comet ISON before it passed around the sun a few weeks ago,” NASA stated.

To be clear, nobody has found organic materials on Europa directly, and even if they were detected it would then be another feat of science to determine if they related to life or not. This does, however, lend credence to theories that life came to Earth through comets and asteroids.

Ample fodder to consider as the community waits for the European Space Agency’s JUICE (JUpiter ICy moons Explorer) to get going to Europa and Jupiter upon its expected launch in 2022. The probe should arrive there in 2030.

Shirley will give a talk on this topic at the American Geophysical Union’s fall meeting on Friday.

Source: NASA

Space Shuttle-Sized Asteroid 2013 XY8 to Fly Past Earth on Dec. 11

Asteroid 2013 XY8 imaged on 2013, December 10, 2013 by E. Guido, N. Howes and M. Nicolini/Remanzacco Observatory.

A newly-discovered asteroid about the size of a space shuttle will fly past Earth on December 11, 2013 at a very safe distance of 760,000 kilometers (470,000 miles). The closest approach of Asteroid 2013 XY8 will be 11:14 UT, and its size is estimated between 31 – 68 meters. This asteroid is zipping along at about 14 kilometers per second, and of course at about 2 lunar distances away, there is no danger of this asteroid hitting Earth. The asteroid was discovered on Dec. 7 by the team at the Catalina Sky Survey, and our friends Ernesto Guido, Nick Howes and Martino Nicolini from the Remanzacco Observatory have provided a follow-up image of the asteroid, taken just this morning.

You can see an animation of it here, and more information at their website.

And as usual with close passing asteroids, the Virtual Telescope Project will is offering a live, online event sharing real-time images of 2013 XY8 with live commentary by their science staff. “It will be a nice opportunity to spy this 40 meter large asteroid moving across the stars,” said Gianluca Masi from the Virtual Telescope Project.

The feed is live now, and you can watch below:

Ready For Your Closeup, Ceres? NASA Spacecraft Gets Closer To Dwarf Planet

Artist's conception of the Dawn spacecraft approaching the asteroid Ceres. Credit: NASA/JPL-Caltech

The next few years will be banner ones for learning about dwarf planets. While the high-profile New Horizons spacecraft zooms towards a Pluto date in 2015, the Dawn spacecraft is making a more stealthy (in terms of media coverage) run at Ceres, which is the smallest and closest dwarf planet to Earth.

The Dawn spacecraft, as readers likely recall, made its first port of call at fellow protoplanet Vesta. What excites scientists this time around is the likelihood of water ice on Ceres’ surface. Vesta, by contrast, was very dry.

Here’s Dawn’s agenda once it gets to Ceres in April 2015:

“Dawn will make its first full characterization of Ceres later in April, at an altitude of about 8,400 miles (13,500 kilometers) above the icy surface. Then, it will spiral down to an altitude of about 2,750 miles (4,430 kilometers), and obtain more science data in its survey science orbit. This phase will last for 22 days, and is designed to obtain a global view of Ceres with Dawn’s framing camera, and global maps with the visible and infrared mapping spectrometer (VIR),” NASA stated.

“Dawn will then continue to spiral its way down to an altitude of about 920 miles (1,480 kilometers), and in August 2015 will begin a two-month phase known as the high-altitude mapping orbit. During this phase, the spacecraft will continue to acquire near-global maps with the VIR and framing camera at higher resolution than in the survey phase. The spacecraft will also image in ‘stereo’ to resolve the surface in 3-D.”

Dawn will then zoom down to an altitude of just 233 miles (375 kilometers) in November 2015 for three months to obtain information about elements and the dwarf planet’s gravity. Dawn will use its Gamma Ray and Neutron Detector (GRaND) to do the first part and a gravity experiment to perform the second.

Ceres. Image credit: NASA
Ceres. Image credit: NASA

To conserve fuel, Dawn will also use a “hybrid” pointing control method to keep it on track, using both reaction wheels and thrusters to stay in the right direction. This is needed because two of its four reaction wheels had “developed excessive friction” by the time Dawn departed Vesta. The hybrid method was tested for 27 hours and successfully concluded Nov. 13. You can check out more about the hybrid mode at this link.

Oh, and as a reminder of what Dawn found at Vesta, check out these Universe Today stories about it discovering hydrogen, learning about its internal structure and taking a close-up of a huge mountain.

This article has been corrected to put Dawn’s correct arrival date.

Watch This Asteroid Not Hit Earth

Earlier today the near-Earth asteroid 2013 NJ sailed by, coming as close as 2.5 lunar distances — about 960,000 km/596,500 miles. That’s a relatively close call, in astronomical terms, but still decidedly a miss (if you hadn’t already noticed.) Which is a good thing since 2013 NJ is estimated to be anywhere from 120–260 meters wide (400-850 feet) and would have caused no small amount of damage had its path intersected ours more intimately.

Luckily that wasn’t the case, and instead we get watch 2013 NJ as it harmlessly passes by in the video above, made from images captured by “shadow chaser” Jonathan Bradshaw from his observatory in Queensland, Australia. Nice work, Jonathan!

Keep tabs on known near-Earth objects on the JPL close pass page here.

NASA Plans To Deepen Asteroid Searches With Planetary Resources

An artist's conception of two tidally locked objects orbiting the Sun from afar. The system: 2010 WG9 may likely look like this. Credit: zmescience

Planetary Resources Inc. — that company that is developing a crowdsourced space telescope to search for asteroids — is planning to work on “crowdsourced software solutions” to make it easier to find asteroids and other near-Earth objects, using NASA-funded data.

NASA announced that Planetary Resources will receive a non-reimbursable Space Act Agreement to help NASA characterize near-Earth objects. It’s the first initiative announced under NASA’s Asteroid Grand Challenge, which the agency announced this summer as a vehicle to find threats to Earth.

A contest is planned in 2014 that will also include participation from the Zooniverse’s forthcoming Asteroid Zoo platform (which includes participation from Planetary Resources). Zooniverse is known for providing ordinary people the chance to participate in astronomical searches, including galaxies and asteroid features.

NASA’s role will be to “develop and manage” the contest, while Planetary Resources is expected to “facilitate the use of NASA-funded sky survey data and help support the algorithm competition and review results,” the agency stated.

NASA is trying mightily to move forward with its plans to capture an explore an asteroid in the next few years, but there’s no guarantee that the agency will receive the funds it wants for it in the fiscal 2014 budget. Politicians have expressed concern that the mission is not interesting the public; besides which, the agency is already battling for funds for its commercial crew and planetary science programs, among others.

Source: NASA

Watch PBS NOVA’s “Asteroid—Doomsday or Payday?”

An asteroid, docile in space but deadly to Earth. Image credit: NASA/JPL

Last night, the US PBS television stations aired a new show from the series NOVA, “Asteroid — Doomsday or Payday.” It portrayed the two sides of asteroids: if a large asteroid collides with Earth, it could set off deadly blast waves, raging fires and colossal tidal waves. But on the other hand, some asteroids are loaded with billions of dollars’ worth of elements like iron, nickel, and platinum, and companies like Planetary Resources are trying to figure out how to take advantage of those elusive resources in space.

You can watch the entire episode below. As with previous shows, viewers in other countries might have difficulty watching the show.

For additional reading, here’s a great article by PBS’s NOVANext about why more isn’t being done about asteroid detection and deflection.

Here’s more info about the B612 Foundation that is featured in the show.

Planetary Resources has some info about why mining asteroids will fuel human expansion into the cosmos,(read here) — watch their video, below:

Asteroids Can Get Shaken And Stirred By Mars’ Gravity

Artist's conception of Mars, with asteroids nearby. Credit: NASA

Asteroids are sometimes called loose rubble piles, which leads to interesting effects if they happen to get close to a planet. A science team in 2010 found out that when asteroids get close to Earth, the gravity of our planet can stir up the dust grains and “refresh” its face, in a sense. Now, scientists have found that Mars can do the same thing.

Here’s the interesting part: the asteroid belt is in between Mars and Jupiter, which means that potentially more asteroids could be changed from the influence of Mars than what happens near Earth.

“Mars is right next to the asteroid belt, and in a way it gets more opportunity than the Earth does to refresh asteroids,” stated Richard Binzel, a professor of planetary sciences at the Massachusetts Institute of Technology who participated in both sets of research.

Artist’s impression of the asteroid (234) Barbara. Thanks to a unique method that uses ESO’s Very Large Telescope Interferometer, astronomers have been able to measure sizes of small asteroids in the main belt for the first time. Their observations also suggest that Barbara has a complex concave shape, best modelled as two bodies that may possibly be in contact. Credit: ESO/L. Calçada
Artist’s impression of the asteroid (234) Barbara. Thanks to a unique method that uses ESO’s Very Large Telescope Interferometer, astronomers have been able to measure sizes of small asteroids in the main belt for the first time. Their observations also suggest that Barbara has a complex concave shape, best modelled as two bodies that may possibly be in contact. Credit: ESO/L. Calçada

“Picture Mars and an asteroid going through an intersection, and sometimes they’ll both come through at very nearly the same time,” Binzel added. “If they just barely miss each other, that’s close enough for Mars’ gravity to tug on [the asteroid] and shake it up. It ends up being this random process as to how these things happen, and how often.”

The initial research in 2010 showed that most asteroids are redder than meteorites. On asteroids, the  surfaces get exposed to cosmic radiation and become redder as time goes on. But when as asteroid gets close to Earth, the planet’s gravity moves around the surface particles and brings fresher bits from underneath. Meteorites that break off from these asteroids would therefore not be as red.

This time around, Binzel’s team looked at other possibilities to “refresh” asteroids, such as collisions or energy from the sun, but concluded that the planets are probably the big reason we see the changed surfaces. You can read more details on the research in the journal Icarus or the preprint version on Arxiv. The lead author on the article was MIT planetary scientist Francesca DeMeo.

Source: MIT

‘Freakish’ Asteroid Has Six Tails, Sheds Stuff Into Space

Pictures of asteroid P/2013 P5 taken by the Hubble Space Telescope. Credit: NASA, ESA, and D. Jewitt (UCLA)

A lawn sprinkler in space. That’s one of the descriptions NASA has for the curious P/2013 P5, which is spewing not one, not two, but six comet-like tails at the same time.

“We were literally dumbfounded when we saw it,” stated David Jewitt of the University of California at Los Angeles, who led the research. “Even more amazing, its tail structures change dramatically in just 13 days as it belches out dust. That also caught us by surprise. It’s hard to believe we’re looking at an asteroid.”

UCLA described the asteroid as a “weird and freakish object” in its own press release.

The mystery started when astronomers spotted a really blotchy thing in space Aug. 27 with the Pan-STARRS survey telescope in Hawaii. The Hubble Space Telescope then swung over to take a look on Sept. 10, revealing all these tails of debris flying off the asteroid.

Pan-STARRS PS1 Observatory just before sunrise on Haleakala, Maui.  Credit: Harvard-Smithsonian Center for Astrophyiscs
Pan-STARRS PS1 Observatory just before sunrise on Haleakala, Maui. Credit: Harvard-Smithsonian Center for Astrophyiscs

It appears, scientists say, that the asteroid is rotating so quickly that it is ripping its very surface apart. They’ve ruled out a collision because the dust leaves in spurts; calculations by team member Jessica Agarwal of the Max Planck Institute for Solar System Research in Lindau, Germany estimated this happened on April 15, July 18, July 24, Aug. 8, Aug. 26 and Sept. 4.

Once the dust gets loose, the sun’s continuous stream of particles then pushes the debris into these extraordinary tails. It’s also possible that this “radiation pressure” contributed to the asteroid’s high spin rate. It appears the team is looking to find more of these objects to see if this is a way that smaller asteroids commonly fall apart.

“In astronomy, where you find one, you eventually find a whole bunch more,” Jewitt stated. “This is just an amazing object to us, and almost certainly the first of many more to come.”

The research appeared in Astrophysical Journal Letters and is also available in prepublished form on Arxiv.

Source: NASA

Lovely Green Olivine On Vesta Paints A Different Formation History

The mineral olivine on Vesta, as seen from hyperspectral data received during the Dawn mission. Credit: Image generated by Alessandro Frigeri and Eleonora Ammannito using VIR data and Framing Camera images.

That ghoul-like sheen on the asteroid Vesta, as seen in the image above, is not some leftover of Hallowe’en. It’s evidence of the mineral olivine. Scientists have seen it before in “differentiated” bodies — those that have a crust and an inner core — but in this case, it’s turning up in an unexpected location.

Finding olivine is not that much of a surprise. Vesta is differentiated and also (likely) is the origin point of diogenite meteorites, which are sometimes olivine-rich. Researchers expected that the olivine would be close to the diogenite rocks, which in Vesta’s case are in areas of the south pole carved out from the mantle.

NASA’s Dawn mission to the asteroid did a search in areas around the south pole — “which are thought to be excavated mantle rocks”, the researchers wrote — but instead found olivine  in minerals close to the surface in the northern hemisphere. These minerals are called howardites and are normally not associated with olivine. So what is going on?

Artist's conception of the Dawn mission. Credit: NASA
Artist’s conception of the Dawn mission. Credit: NASA

Basically, it means that Vesta’s history was far more complex than we expected. This situation likely arose from a series of impacts that changed around the eucritic (stony meteorite) crust of Vesta:

“A generalized geologic history for these olivine-rich materials could be as follows: ancient large impacts excavated and incorporated large blocks of diogenite-rich and olivine-rich material into the eucritic crust, and subsequent impacts exposed this olivine-rich material,” the researchers wrote.

“This produced olivine-rich terrains in a howarditic background, with diogene-rich howardites filling nearby, eroded, older basins.”

Dawn, by the way, has completed its time at Vesta and is now en route to another large asteroid, Ceres. But there’s still plenty of data for analysis. This particular research paper was led by E. Ammannito from the Institute of Astrophysics and Space Planetology (Istituto di Astrofisica e Planetologia Spaziali) in Rome. The research appears in this week’s Nature and should be available shortly at this link.

What If Earth Was Threatened by An Asteroid Strike? Astronaut Panel Brings Up Ideas To Search, Deflect These Threats

Computer generated simulation of an asteroid strike on the Earth. Credit: Don Davis/AFP/Getty Images

“If we get hit 20 years from now, that’s not bad luck. That’s stupidity.”

That’s what former NASA astronaut Ed Lu has to say about asteroids and our efforts to search for them. He delivered those comments at a panel discussion today at New York’s American Museum of Natural History. He and several other astronauts spoke on behalf of the Association of Space Explorers (which, as the name implies, consists of astronauts, cosmonauts and the like.)

We guess that as astute readers of our publication, you know that a planetary threat from asteroids (and comets) exists. And there’s certainly more we can do; when that 17-meter asteroid blasted Russia earlier this year, Lu said most space agencies learned about it from social media!

So what’s being done about these threats? Here’s a roundup of the panel discussion’s information and some related information.

Asteroid searching and deflection:
  • Since Lu is the CEO of the B612 Foundation, there was a heavy emphasis on the agency’s proposed Sentinel telescope. Intended to launch in 2018, it would survey the solar system in infrared and seek out potential hazards.
  • To date, NASA’s NEO Observations Program has found 95 per cent of near-Earth objects larger than one kilometer, Jet Propulsion Laboratory scientist Amy Mainzer told Universe Today in a separate conversation today.
  • Mainzer also brought us up to speed on the Near-Earth Object Camera (NEOCam) proposal, which she’s been working on since 2005. Her group received technology development funding in 2010 to improve their infrared detectors, which succeeded in passing recent tests. Their group will seek more funding for NASA in the next opportunity.
  • The WISE spacecraft’s NEOWISE mission, meanwhile, is going to restart early next year, Mainzer added. “While NEOWISE is not nearly as capable as NEOCam will be, it will improve our knowledge of the diameters and albedos of  about 2,000 NEOs and tens of thousands of main belt asteroids,” Mainzer wrote. “With the NEOWISE prime mission, we discovered more than 34,000 new asteroids and observed >158,000 in total. We have used our data from NEOWISE to set constraints on the number of NEOs and potentially hazardous asteroids.”
Former NASA astronaut Tom Jones shared this slide concerning ideas for asteroid defense. Credit: Tom Jones/Association for Space Explorers/AMNH/Ustream (screenshot)

Getting the United Nations involved:

 

  • This week, the United Nations Committee on the Peaceful Uses of Outer Space adopted several steps related to asteroids. It’s planning an International Asteroid Warning Group (to share detections and warn of potential impacts), an Impact Disaster Planning Advisory Group, and a Space Missions Planning and Advisory Group (which would look at deflection missions, options, costs, etc.)
  • Why go with the United Nations? In the panel, NASA Apollo astronaut Rusty Schweickart explained it this way: deciding how to deflect an asteroid posts risks. You might be moving the impact path past a country that would not have been at risk before the deflection. It’s best to make such moves internationally, rather than having (say) the United States make a decision that could increase Russia’s risk to an asteroid.
  • The problem? Working by committee is slow, says former Romanian astronaut Dumitru-Dorin Prunariu: “You would think with the United Nations that we started to think about asteroids only in 2007, 8 or 9, but the first input was done by 1999 at the Unispace conference, the United Nations International Conference in Space.” People have been working hard, to be sure, but making a good, inclusive plan just takes time. An action team was formed in 2001, a working group was in place by 2007, and the adoptions by UNCOPUOS (as we stated earlier) took place this week.
An artist's conception of a space exploration vehicle approaching an asteroid. Credit: NASA
An artist’s conception of a space exploration vehicle approaching an asteroid. Credit: NASA
 Cost of all of this:
  • Schweickart: “Money is hardly an issue in this. This is a very inexpensive thing to do. It’s organizational setting the actual criteria, thresholds whatever.” It would only cost 1% of the NASA budget for the next 10 years, and less than 0.5% after that. (The NASA budget request for 2014 was $17.7 billion, so 1% of that is $177 million.)
  • The panel members emphasized that it’s best to start the search early and find the threatening asteroids before things become an emergency. If a moderate-sized asteroid was discovered only a few months out, it might be better just to evacuate the affected area rather than try to pull together a last-minute mission to stop the asteroid.