Here is the latest of the Planetary Society‘s series The Planetary Post with Robert Picardo:
Star parties are magical events where one can observe the wonders of our night sky…and have a surprise Star Trek: Voyager reunion. Also, news about seven Earth-sized planets orbiting a red dwarf star, plus learn how you can help prevent an asteroid impact disaster.
Leaders of the quest to find, understand and protect ourselves from the asteroids and comets called Near Earth Objects gathered with host Mat Kaplan for a live conversation about this existential threat from space. This special episode presents excerpts of that lively discussion with JPL Senior Research Scientist Amy Mainzer, Manager of NASA/JPL’s Center for Near Earth Object Studies Paul Chodas, and NASA’s Planetary Defense Officer Lindley Johnson. Also on stage was Planetary Society Director of Science and Technology Bruce Betts. Bruce stayed for this week’s What’s Up segment.
The SpaceX Dragon cargo spacecraft, launched last Sunday from the Kennedy Space Center, berthed today to the International Space Station. Astronauts on the station reached out with a robotic arm, snagged the Dragon, and then attached the craft to the station:
The Dragon carries over 5,000 pounds (2300 kg) of supplies, hardware, and research materials, including 21 experiments from students in grade school through high school who are participating in the Student Spaceflight Experiments Program (SSEP) . This is the 9th SSEP mission to the ISS:
This was a really exciting launch for the team at DreamUp as we had the fantastic V3PO students fly all the way from Germany to join us for the launch. These students crowd-funded their plant-growth research project and got some great advisors on board, including Airbus and BASF Crop Protection. With the team put together, the students commenced their vegetative plant propagation.
Learn more about the plant growth experiment here.
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All together, DreamUp was able to bring over 55 student researchers and advisors to this launch. We really saw our students’ perseverance when on the first planned launch date…the launch was scrubbed with just 13 seconds to go! They held on to all of their excitement and brought it to the launch the following day, with big smiles and loud cheers as they saw the rocket go up, holding on tight to their experiments.
The V3PO team receiving their DreamUp Wings certificates with the view of the Vehicle Assembly Building (VAB) in the background. Photo credits DreamUp
Last year alone, we launched over 60 educational payloads to space on five different rockets, designed by student researchers from 7 different countries. We’ve also grown our myLAUNCH and DreamUp graduation programs – offering 50 students a once-in-a-lifetime opportunity to attend a rocket launch and honoring over 100 DreamUp graduates with certificates to celebrate their incredible achievements and welcome them to our growing alumni community.
Part of DreamUp’s core mission is to immerse students and educators at every level of education in the wonder of outer space through engaging programs that highlight the multifaceted applications of STEM skills and the growing opportunities in the global space industry. In 2016, we produced and released our first-ever, completely free, curriculum for educators. Located on our website, the “Eye in the Sky” curriculum was developed in partnership with Jenny Pieratt at CraftED and incorporates space-based data and images to help students determine whether the Earth is a just planet. All are welcome to download and use this Next Generation Science Standard-compliant resource at no cost, but if you do, please send us feedback so we can incorporate your thoughts in our next curriculum release!
Looking ahead, we foresee a very active 2017. As we implement the first-ever DreamUp Challenge, realize partnership agreements with some of the largest school districts in the country, and invite more and more student researchers to experience the wonder of rocket launches, DreamUp will continue to improve our services as the leading provider for experiential learning in space.
On Feb. 17, 2005, NASA’s Cassini spacecraft was making the first-ever close pass over Saturn’s moon Enceladus as it worked through its detailed survey of the planet’s icy satellites. Exciting, to be sure, just for the thrill of exploration. But then Cassini’s magnetometer instrument noticed something odd.
Since NASA’s two Voyager spacecraft made their distant flybys of Enceladus about 20 years prior, scientists had anticipated the little moon would be an interesting place to visit with Cassini. Enceladus is bright white — the most reflective object in the solar system, in fact — and it orbits in the middle of a faint ring of dust-sized ice particles known as Saturn’s E ring. Scientists speculated ice dust was being kicked off its surface somehow. But they presumed it would be, essentially, a dead, airless ball of ice.
What Cassini saw didn’t look like a frozen, airless body. Instead, it looked something like a comet that was actively emitting gas. The magnetometer detected that Saturn’s magnetic field, which envelops Enceladus, was perturbed above the moon’s south pole in a way that didn’t make sense for an inactive world. Could it be that the moon was actively replenishing gases it was breathing into space?
Thus began a hunt for clues that has turned out to be Cassini’s most riveting detective story.
“Enceladus was so exciting that, instead of just three close flybys planned for our four-year primary mission, we added 20 more, including seven that went right through the geysers at the south pole,” said Linda Spilker, Cassini project scientist at NASA’s Jet Propulsion Laboratory, Pasadena, California.
By following the trail of scientific breadcrumbs, Cassini eventually found that Enceladus harbors a global ocean of salty water under its icy crust, possibly with hydrothermal vents on its seafloor. The trail of clues that began with a puzzling magnetometer reading led to an understanding that the moon — and perhaps many small, icy moons like it throughout the cosmos — could potentially have the ingredients needed for life.
“Half the excitement of doing science is that you sometimes find yourself going in a totally different direction than you expected, which can lead to amazing discoveries,” said Spilker. “That little anomaly in Cassini’s magnetometer signal was unusual enough that it eventually led us to an ocean world.”
Launched in 1997, the Cassini mission is currently in its final year of operations, performing weekly ring-grazing dives just past the outer edge of Saturn’s rings. In April, the spacecraft will begin its Grand Finale, plunging through the gap between the rings and the planet itself, leading up to a final plunge into Saturn on September 15.
Illustration showing the bending of Saturn’s magnetic field near Enceladus that was detected by Cassini’s magnetometer. Credit: NASA/JPL-Caltech > Full image and caption
Cassini has been touring the Saturn system since arriving in 2004 for an up-close study of the planet, its rings and moons, and its vast magnetosphere. Cassini has made numerous dramatic discoveries, besides the activity at Enceladus, including liquid methane seas on another moon, Titan.
The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA’s Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the mission for NASA’s Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.
The full-sized image of the Yellowknife Bay Formation on Mars looks like you could just walk right out onto it. (But wear a spacesuit if you do.) In this article, spots like Yellowknife are providing insights as well as contradictions about the conditions of the planet in its early eons:
Bedrock at this site added to a puzzle about ancient Mars by indicating that a lake was present, but that little carbon dioxide was in the air to help keep a lake unfrozen. Full image and caption
Mars scientists are wrestling with a problem. Ample evidence says ancient Mars was sometimes wet, with water flowing and pooling on the planet’s surface. Yet, the ancient sun was about one-third less warm and climate modelers struggle to produce scenarios that get the surface of Mars warm enough for keeping water unfrozen.
A leading theory is to have a thicker carbon-dioxide atmosphere forming a greenhouse-gas blanket, helping to warm the surface of ancient Mars. However, according to a new analysis of data from NASA’s Mars rover Curiosity, Mars had far too little carbon dioxide about 3.5 billion years ago to provide enough greenhouse-effect warming to thaw water ice.
The same Martian bedrock in which Curiosity found sediments from an ancient lake where microbes could have thrived is the source of the evidence adding to the quandary about how such a lake could have existed. Curiosity detected no carbonate minerals in the samples of the bedrock it analyzed. The new analysis concludes that the dearth of carbonates in that bedrock means Mars’ atmosphere when the lake existed — about 3.5 billion years ago — could not have held much carbon dioxide.
“We’ve been particularly struck with the absence of carbonate minerals in sedimentary rock the rover has examined,” said Thomas Bristow of NASA’s Ames Research Center, Moffett Field, California. “It would be really hard to get liquid water even if there were a hundred times more carbon dioxide in the atmosphere than what the mineral evidence in the rock tells us.”
Bristow is the principal investigator for the Chemistry and Mineralogy (CheMin) instrument on Curiosity and lead author of the study being published this week in the Proceedings of the National Academy of Sciences.
Curiosity has made no definitive detection of carbonates in any lakebed rocks sampled since it landed in Gale Crater in 2012. CheMin can identify carbonate if it makes up just a few percent of the rock. The new analysis by Bristow and 13 co-authors calculates the maximum amount of carbon dioxide that could have been present, consistent with that dearth of carbonate.
In water, carbon dioxide combines with positively charged ions such as magnesium and ferrous iron to form carbonate minerals. Other minerals in the same rocks indicate those ions were readily available. The other minerals, such as magnetite and clay minerals, also provide evidence that subsequent conditions never became so acidic that carbonates would have dissolved away, as they can in acidic groundwater.
The dilemma has been building for years: Evidence about factors that affect surface temperatures — mainly the energy received from the young sun and the blanketing provided by the planet’s atmosphere — adds up to a mismatch with widespread evidence for river networks and lakes on ancient Mars. Clues such as isotope ratios in today’s Martian atmosphere indicate the planet once held a much denser atmosphere than it does now. Yet theoretical models of the ancient Martian climate struggle to produce conditions that would allow liquid water on the Martian surface for many millions of years. One successful model proposes a thick carbon-dioxide atmosphere that also contains molecular hydrogen. How such an atmosphere would be generated and sustained, however, is controversial.
The new study pins the puzzle to a particular place and time, with an on-the-ground check for carbonates in exactly the same sediments that hold the record of a lake about a billion years after the planet formed.
For the past two decades, researchers have used spectrometers on Mars orbiters to search for carbonate that could have resulted from an early era of more abundant carbon dioxide. They have found far less than anticipated.
“It’s been a mystery why there hasn’t been much carbonate seen from orbit,” Bristow said. “You could get out of the quandary by saying the carbonates may still be there, but we just can’t see them from orbit because they’re covered by dust, or buried, or we’re not looking in the right place. The Curiosity results bring the paradox to a focus. This is the first time we’ve checked for carbonates on the ground in a rock we know formed from sediments deposited under water.”
The new analysis concludes that no more than a few tens of millibars of carbon dioxide could have been present when the lake existed, or it would have produced enough carbonate for Curiosity’s CheMin to detect it. A millibar is one one-thousandth of sea-level air pressure on Earth. The current atmosphere of Mars is less than 10 millibars and about 95 percent carbon dioxide.
“This analysis fits with many theoretical studies that the surface of Mars, even that long ago, was not warm enough for water to be liquid,” said Robert Haberle, a Mars-climate scientist at NASA Ames and a co-author of the paper. “It’s really a puzzle to me.”
Researchers are evaluating multiple ideas for how to reconcile the dilemma.
“Some think perhaps the lake wasn’t an open body of liquid water. Maybe it was liquid covered with ice,” Haberle said. “You could still get some sediments through to accumulate in the lakebed if the ice weren’t too thick.”
A drawback to that explanation is that the rover team has sought and not found in Gale Crater evidence that would be expected from ice-covered lakes, such as large and deep cracks called ice wedges, or “dropstones,” which become embedded in soft lakebed sediments when they penetrate thinning ice.
If the lakes were not frozen, the puzzle is made more challenging by the new analysis of what the lack of a carbonate detection by Curiosity implies about the ancient Martian atmosphere.
“Curiosity’s traverse through streambeds, deltas, and hundreds of vertical feet of mud deposited in ancient lakes calls out for a vigorous hydrological system supplying the water and sediment to create the rocks we’re finding,” said Curiosity Project Scientist Ashwin Vasavada of NASA’s Jet Propulsion Laboratory, Pasadena, California. “Carbon dioxide, mixed with other gases like hydrogen, has been the leading candidate for the warming influence needed for such a system. This surprising result would seem to take it out of the running.”
When two lines of scientific evidence appear irreconcilable, the scene may be set for an advance in understanding why they are not. The Curiosity mission is continuing to investigate ancient environmental conditions on Mars. It is managed by JPL, a division of Caltech in Pasadena, for NASA’s Science Mission Directorate, Washington. Curiosity and other Mars science missions are a key part of NASA’s Journey to Mars, building on decades of robotic exploration to send humans to the Red Planet in the 2030s. For more about Curiosity, visit: www.nasa.gov/curiosity
Screen capture from video of blue jet of lightning as seen from the ISS.
For years, their existence has been debated: elusive electrical discharges in the upper atmosphere that sport names such as red sprites, blue jets, pixies and elves. Reported by pilots, they are difficult to study as they occur above thunderstorms.
ESA astronaut Andreas Mogensen during his mission on the International Space Station in 2015 was asked to take pictures over thunderstorms with the most sensitive camera on the orbiting outpost to look for these brief features.
Denmark’s National Space Institute has now published the results, confirming many kilometre-wide blue flashes around 18 km altitude, including a pulsating blue jet reaching 40 km. A video recorded by Andreas as he flew over the Bay of Bengal at 28 800 km/h on the Station shows the electrical phenomena clearly – a first of its kind.
The Station’s low orbit makes it an ideal platform from which to observe and study these unusual electrical atmospheric phenomena. In the video below,
ESA astronaut Andreas Mogensen explains the phenomena he filmed over India from the International Space Station’s Cupola observatory in September 2015 during his postflight tour at ESA’s technical heart ESTEC in The Netherlands.
The film shows lightning illuminating clouds and recently discovered phenomena called blue jets and Red Sprites.
As part of his 10-day mission Andreas performed an experiment called Thor after the god of thunder, lightning and storms in Nordic mythology. Initiated by the Technical University of Denmark, Thor had Andreas test a new thundercloud imaging system that looks at the electrification of lighting.
Researchers are particularly interested in newly-discovered lights that occur in the upper atmosphere during thunderstorms called red sprites, blue jets and elves. Sprites last 20 milliseconds at most, and to capture them on camera is a real challenge. They received their name because of their elusive nature. Blue jets are found up to 50 km altitude with Red Sprites occurring between 60-80 km altitude.
Andreas received the coordinates of a few possible thunderstorms together with the times and instructions on which lens, filter and camera settings to use.
Some of the most violent electric discharges are very difficult to capture from the ground because the atmosphere blocks radiation. Apart from covering all the main thunderstorm regions, the International Space Station brings scientists as close as possible to the electric phenomena. Its great vantage point has the lowest orbit available for observation at around 400 km altitude – imaging satellites mostly operate at 800 km.
