The South Rim of Aristarchus

LROC view looking obliquely of the south rim of Aristarchus from the west (NASA/GSFC/Arizona State University)

Flying over at an altitude of 135 km, NASA’s Lunar Reconnaissance Orbiter captured this lovely oblique view of the crater Aristarchus, looking down at the 40-km (25-mile) -wide crater’s southern rim from the west.

The broad flank of Aristarchus’ 300-meter (980-foot) central peak and surrounding hills can be seen at left, casting lengthening shadows in the setting sun.

Named after the Greek astronomer who first proposed a controversial heliocentric model for the Solar System in the 3rd century BCE, Aristarchus is a prominent crater located near the Moon’s northwestern limb within the geologically-diverse Oceanus Procellarum — the “Ocean of Storms.” Surrounded by rays of bright ejecta that extend down its stepped rim, the floor of Aristarchus drops 3.7 km (2.3 miles) below the surrounding lunar landscape.

Read more: LRO Lets You Stand on the Rim of Aristarchus Crater

The bright material seen in the ejecta streaks seems to echo the patterns of light and dark material lining the slopes of Aristarchus’ central peak, suggesting that they may be the made of similar material.

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Detail of the 4.5-km-long central peak of Aristarchus (NASA/GSFC/Arizona State University)

The impact that created Aristarchus an estimated 450 million years ago excavated subsurface material, melting and spraying it tens of kilometers over the surrounding plateau. It’s thought that the central peak is likely composed of the same stuff, dredged up by the impact and frozen in place.

Future lunar explorers, should they ever visit this region, would be able to collect samples from the base of the central peak and compare them to samples from the bright rays to see if they match up, allowing researchers to learn about the composition of the material underlying the plateau from rocks scattered conveniently around the surface… this is the beauty of such (relatively) recent craters! The digging’s already been done for us.

Read more about this on Arizona State University’s LROC site and explore a zoomable version of the original NAC frame here.

The ‘Bonus’ Full Moon of 2012

The Moon and Jupiter above the dishes in Canberra, Australia. Credit: Carlos Orue.

The full Moon today is considered a bonus for 2012, since it is the 13th full Moon of the year. But this full Moon has also been a bonus in the sense that we’re getting several nights in a row of nearly full Moons. According to Universe Today’s Phases of the Moon App, the face of the Moon on the night of the 25th was 96% illuminated; on the 26th it was 99% illuminated; the night of the 27th/morning of the 28th was the full Moon, (officially, the Moon was most full at 10:21 UTC (4:21 EST this morning), and tonight, the 28th, the face of the Moon is again 99% illuminated. And if you’re enjoying a wintery landscape like I currently am, the brilliance of the Moonlight on snow is bright enough to keep you awake at night.

Enjoy some great astrophotos submitted for photographers around the world of the bonus — and final — full Moon of 2012.

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The last full Moon of 2012 — the Full Cold Moon, as seen from the James C. Veen Observatory near Lowell, Michigan. Credit: Kevin on Flickr.

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The last full moon of the year as seen from the Middle Eastern Technical University Physics department in Ankara, Turkey. Credit: Nükleer Kedi

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Full Moon of December. Credit: Henna Khan

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Full Moon, December 27, 2012 from London, England. Credit: Sculptor Lil.

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The Third Day of Christmas Moon. Credit: Andrei Juravle

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Closeup of Tycho Crater on Dec. 23, 2012. Credit: Fred Locklear

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Closeup of the Moon on Dec. 26, 2012. Credit: César Cantú

Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.

Amazing Video of a Lunar Occultation

Captured on camera by astrophotographer Rafael Defavari from his location in São Bernardo do Campo, Brazil, this video shows the Moon passing in front of Jupiter during an occultation event on December 25, 2012. Nice work!

The video plays at 5x actual speed.

Although Jupiter appeared to be “right next to” the Moon on Christmas night from our viewpoint here on Earth, in reality the two worlds were 388 million miles (625 million km) apart. The Moon blocked the view of the giant planet for a full hour and ten minutes.

‘Tis the season for lunar occultations, too… the last one occurred on November 28, and the next will be on January 22, 2013.

See more photos of the Dec. 25 event from viewers in Brazil here.

Video credit: Rafael Defavari

A Color View of Darling Dione

Color-composite of Dione made from raw Cassini images acquired on Dec. 23, 2012. (NASA/JPL/SSI. Composite by J. Major.)

Although made mostly of ice and rock, Saturn’s moon Dione (pronounced dee-oh-nee) does have some color to it, as seen in this color-composite made from raw images acquired by Cassini on December 23.

700 miles (1120 km) wide, Dione is covered pole-to-pole in craters and crisscrossed by long, bright regions of “wispy line” terrain — the reflective faces of sheer ice cliffs and scarps that are too steep for darker material drifting in from Saturn’s E ring to remain upon.

The composite  was assembled from raw images captured in red, green and blue visible light wavelengths by Cassini from a distance of 154,869 miles (249,238 km).

The view above looks at a region on Dione’s mid-northern hemisphere. The bright-walled crater in the center surrounded by warmer-hued terrain is named Creusa, and the long rift system next to it is Tibur Chasmata, which runs north-to-south. Dione’s north pole is to the upper left.

Dione’s heavily cratered areas are most common on its trailing hemisphere. Logically, a moon’s leading hemisphere should be the more heavily cratered, so it has been hypothesized that a relatively recent impact spun Dione around 180 degrees. The moon’s small size mean that even a modest-scale impact could have done the job.

Relative sizes of Earth, Moon and Dione (J. Major)

Dione orbits Saturn at a distance of 209,651 miles (377,400 km), closer than our Moon is to us.

See more images and news from the Cassini mission here. And for more on Dione, see some of my previous posts on Lights in the Dark.

‘Live’ Tweeting Apollo 17’s Mission

Lunar and Planetary Rovers covers both the manned rovers used on the final three Apollo lunar missions with the unmanned rovers used to explore the surface of Mars - under one book. Photo Credit: NASA/Jack Schmitt

 

40 years ago on December 19, 1972, Apollo 17 splashed down on Earth, marking the end of the manned moon missions. The astronauts came back with a treasure trove of rocks collected in 22 hours of extra-vehicular activity on the lunar surface, including “orange” soil that ended up coming from an ancient volcano.

Twitter wasn’t around back then, but anyone tuning into several Twitter accounts recently week would have a chance to experience what it could it have been like. Using mission transcripts and historical accounts of Apollo 17, these folks took it upon themselves to tweet the Apollo 17 mission, moment by moment, as “live” as possible.

Universe Today caught up with two of the tweeters. This is an edited version of what they said about the experience.

Liz Suckow (@LizMSuckow), a NASA contract archivist who tweeted on her own time

Researching a mission is divided into two parts, prelaunch and flight. For prelaunch, I use whatever official NASA documents, histories, and relevant astronaut and mission controller autobiographies I can find.

From what I’ve seen on the missions I’ve tweeted, until Apollo, no prelaunch conversation was transcribed at all. For Apollo, the last hour or so before liftoff is on the mission transcript. So, I can schedule those tweets. But, prelaunch activities for the astronauts start as long as 10 hours before liftoff. So, I use whatever resources I can to find references to the time of important events, and the rest of the prelaunch scheduling is educated guesswork. Flight is easy.

I have been trying to tweet as if I was the Johnson Space Center public affairs officer during the particular mission. When I joined Twitter in November of 2010 and was looking for accounts to follow, I came across a dead feed from JSC, I can’t remember the account name, that tweeted what had happened during a shuttle mission in real time.

Apollo 17, the only lunar mission to launch at night. Image Credit: NASA/courtesy of nasaimages.org

I thought, “Wow, that’s cool! Somebody ought to do that for the historical missions.” The celebration of the 40th anniversary of Apollo was still a big deal at NASA at the time, and the next mission up was Apollo 14. I figured someone else at NASA would have the same idea, but it was never mentioned.  So, I figured I would do it on my personal account, just to see if it could be done and if anybody else (even if it was only a few people) liked the idea.

I am definitely going to be doing another one. I think the next anniversary is either Gordon Cooper‘s Mercury flight in May 2013, or the first Skylab missions. Not quite sure how I want to handle Skylab yet, may throw that one open to followers for ideas. Why do I do it? I do it because it is fun. Sometimes, I get so mentally involved the mission I get excited for what’s coming next as I am scheduling the tweets (even though I know full well what’s going to happen).

Buck Calabro (@Apollo17History), space fan who live-Tweeted along with Thomas Rubatscher

I’m live tweeting because I’m interested in Apollo. It’s a life-long interest. I myself live Tweet mostly by actually typing the tweet into HootSuite.com or Twitter.com. I have collaborated with Thomas by creating a spreadsheet of candidate tweets that he can upload into HootSuite’s bulk uploader for time-delayed tweeting.

My tweets mostly center around the command module pilot, Ron Evans. He spent three days all by himself in the CM, doing photography, mapping and other experiments. Not exactly the same sort of fame that the moonwalkers got. It’s a different kind of grit. Imagine being Evans, as AMERICA goes around the limb of the moon, completely cut off from every human being in the universe. Nothing but some fans, pumps and procedure to keep you going.

I have no plans for leveraging the Tweets. I’ll probably do another one someday. It’s a lot of work. As far as resources, I prefer source material. I have copies of the original transcripts for ground-to-air communications. The Apollo Lunar Surface Journal is a treasure trove of images and transcripts for the lunar surface portion of the mission, and the Lunar and Planetary Institute has an extensive catalog of imagery by camera magazine (which can be found in the transcripts.) NASA has scanned vast quantities of Apollo-era documentation, and the experiment results are likewise mostly available in the public domain.

‘NASA Johnson Style’ Parodies ‘Gangnam Style’ Music Video

Check this out and get in the groove to enjoy some really cool fun from NASA

NASA interns and NASA astronauts have joined forces to create a very humorous and entertaining music video parody of the “Gangnam Style” mega hit by international pop sensation PSY – It’s called “NASA Johnson Style” and its New!

A team of interns from NASA’s Johnson Space Center (pictured below) in Houston created original lyrics, convinced several initially incredulous astronauts to dance along and shot the video at several NASA centers. Then they integrated the whole kit and kaboodle with the “Gangnam Style” instrumental track. Scotty would be proud of the intricate engineering demanded to pull this off – but where are the tribbles !

Image caption: Mike Massimino (center) poses with the intern video team after filming at JSC. Photo credit: Nicole Cloutier

The video features a fun loving crew of NASA astronauts including Mike Massimino, who deftly repaired the Hubble Space Telescope twice among other things, Clayton Anderson and Tracy Caldwell Dyson who lived and worked for many months aboard the International Space Station, and Mike Coats, a Shuttle commander and the retiring Director of the Johnson Space Center.

The video also features actual footage from the International Space Station , Apollo Moonwalks, Curiosity on Mars, Dawn at Vesta, Houston Mission control, the SLS and Orion Crew vehicle as well as real research labs and scientists here on Earth. So it’s fun and meant to be educational as well.

“Gangnam Style” by the Korean singing star PSY is the most popular YouTube music ever and is enjoyed by millions more every day since it was released last summer. It has spawned numerous other parodies.

And in case you missed last summer’s mega hit parody straight from the Red Planet – click on this: “We’re NASA and We Know It (Mars Curiosity)” – Note: this is NOT a NASA production

Now, turn up the volume and enjoy some light hearted cheer in this Holiday season.

Ken Kremer

End of Mission: GRAIL Spacecraft Impact a Mountain on the Moon

The planned path of the GRAIL spacecrafts’ final orbit. Credit: NASA

“So long, Ebb and Flow, and we thank you,” said GRAIL project manager David Lehman of NASA’s Jet Propulsion Laboratory after the twin GRAIL spacecraft completed a planned formation-flying double impact into the southern face of 2.5-kilometer- (1.5-mile-) tall mountain on a crater rim near the Moon’s north pole. Mission team members estimate the two spacecraft were traveling at a speed of 1.7 kilometers per second (3,760 mph), and likely broke apart on impact. NASA said that most of what remains of the washing machine-sized spacecraft are probably buried in shallow craters, and the size of those craters will hopefully be determined when NASA’s Lunar Reconnaissance Orbiter is able to image the impact site in about two weeks.

NASA has honored the GRAIL team’s request to name Ebb and Flow’s impact sites after astronaut Sally Ride, who passed away earlier this year. She was America’s first woman in space and a member of the GRAIL mission team.

A simulation of the GRAIL impacts:

Impact occurred at 10:28:51 UTC (5:28:51 p.m. EST) and 10:29:21 UTC (5:29:21 p.m. EST). Right now it is night at the impact site, so sunlight should return within two weeks, enabling imaging of the site. LRO also took “before” images of the site during previous daylight orbits.

The impact marked a successful end to the GRAIL(Gravity Recovery and Interior Laboratory)mission, which in just a 90-day prime mission generated the highest-resolution gravity field map of any celestial body — including Earth — and determined the inner crust of the Moon is nearly pulverized.

“Ebb and Flow have removed a veil from the Moon,” said GRAIL principal investigator Maria Zuber during a televised commentary of the impacts today, adding that the mission will enable discoveries for years to come.

Data from GRAIL’s extended mission and main science instruments are still being analyzed, and the findings will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.

GRAIL was NASA’s first planetary mission to carry cameras fully dedicated to education and public outreach. Ride, who died in July after a 17-month battle with pancreatic cancer, led GRAIL’s MoonKAM (Moon Knowledge Acquired by Middle School Students) Program through her company, Sally Ride Science. The camera took more than 115,000 total images of the lunar surface, and imaging targets were proposed by middle school students from across the country and the resulting images returned for them to study.

“Sally was all about getting the job done, whether it be in exploring space, inspiring the next generation, or helping make the GRAIL mission the resounding success it is today,” said Zuber. “As we complete our lunar mission, we are proud we can honor Sally Ride’s contributions by naming this corner of the Moon after her.”

Last Friday, Ebb and Flow, the two spacecraft comprising NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission, were commanded to descend into a lower orbit that would result in an impact Monday on a mountain near the Moon’s north pole.

Fifty minutes prior to impact, the spacecraft fired their engines until the propellant was depleted. The maneuver was designed to determine precisely the amount of fuel remaining in the tanks. This will help NASA engineers validate computer models to improve predictions of fuel needs for future missions.

Screenshot of engineering data showing trajectory of the two GRAIL spacecraft about 2 minutes before Ebb’s impact. Via NASA TV.

“Ebb fired its engines for 4 minutes 3 seconds, and Flow fired its for 5 minutes 7 seconds,” Lehman. “It was one final important set of data from a mission that was filled with great science and engineering data.”

Launched in September 2011, Ebb and Flow had been orbiting the moon since Jan. 1, 2012. The probes were intentionally crashed into the lunar surface because they did not have sufficient altitude or fuel to continue science operations.

NASA Looks Towards Next Mission to the Moon

NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) Observatory sits beside a radio frequency antenna inside an enclosure that blocks external static to detect electromagnetic emissions. Image credit: NASA Ames

With the GRAIL mission ending today, NASA is preparing for its next lunar orbiter mission, which could help pave the way for a potential future human mission to the Moon. While the Moon seems to be an ‘on-again-off-again’ potential human destination, as the GRAIL mission points out, studies of our closest neighbor in space continues to reveal surprises.

But if we are ever going to establish any sort of long-term presence on the Moon, scientists and engineers will have to understand more about the environmental conditions that they’re dealing with. Lunar dust is an environmental factor that requires much more exploration and study, as it may pose one of the biggest problems for humans on the Moon. Lunar dust is as fine as talcum powder and abrasive enough to cause long term problems to the lenses and seals central to the operation of mechanical equipment — not to mention hazards to human health — during any lengthy stay on the Moon.

Artist concept of the LADEE spacecraft in orbit at the Moon. Credit: NASA

To study this unique lunar environmental phenomenon, NASA is in the process of testing the Lunar Atmosphere and Dust Environment Explorer (LADEE) in preparations for its upcoming launch. Recently, LADEE integrated the last of its three main science instruments. The three instruments to be launched with the craft are the Ultraviolet and Visible Light Spectrometer, which will analyze the light signatures of the materials it detects on the Moon, the Neutral Mass Spectrometer, set to detect differences in what little atmosphere there is on the Moon over multiple orbits, and the Lunar Dust Experiment, which will collect and analyze any dust particles that are floating around the sparse atmosphere that LADEE will be flying in.

In addition to it’s science experiments, LADEE will be technically unique in a few ways. First, it is pioneering NASA’s Modular Common Bus architecture, which will hopefully increase the compatibility between future lunar spacecraft’s communications and power systems and thereby decrease their cost.

LADEE will also carry a “technology demonstration payload,” which will allow it to communicate with Earth using lasers rather than radio waves. This will dramatically increase the speed of information transfer between the spacecraft and its controllers, resulting in almost broadband-internet levels of data exchange. If this technology proves successful it is likely to be used on future lunar exploration missions as well.

LADEE is currently undergoing a battery of environmental tests. Acoustic, vibration, shock and thermal-vacuum test still await the spacecraft after it recently passed the electromagnetic interference test. Assuming it manages to keep its clean bill of health, the spacecraft could be launched on it’s 160 day mission as early as August 2013. With its help, humanity will have a better understanding of how to combat one of the most unfriendly aspects of the lunar environment.

More information on LADEE from NASA

Apollo’s Final Footsteps, 40 years later

Image Credit: NASA/Eugene Cernan

Will there come a time when we on Earth can look up at the Moon and know that people are living there permanently?

40 years ago today, humans left the Moon for the last time during our visits during the Apollo program. Author Andrew Chaikin has been creating a series of videos on why space exploration is important, and to mark the 40th anniversary of the last human footsteps on the moon, he looks back at Apollo 17’s explorations and explains why he believes the Moon is the solar system’s “jewel in the crown,” beckoning us to return.


“The Moon is an ideal place for future astronauts to tackle the enormous challenges of living on other worlds,” Chaikin says, “a kind of outward-bound school for learning to live off-planet that is just three days away from home.”

You can see all of Chaikin’s videos here, and here’s an interview we did with Chaikin last year, “Was the Apollo Program an Anomaly?

Additionally, read a great article the Amy Shira Teitel wrote for us last year about the Apollo 17 mission’s last Moonwalk.

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Endgame: GRAIL Spacecraft to Slam into Lunar Crater Rim on December 17

The GRAIL mission will come to a dramatic end on Monday as the two spacecraft will be commanded to crash into the rim of an unnamed crater near the Moon’s north pole. This is all according to plan, as the two spacecraft are running out of fuel after being in lunar orbit since New Year’s Day 2012.

“We successfully completed our primary science mission,” said Principal Investigator Maria Zuber, “ and, frankly, in my wildest dreams I don’t think this mission could have gone any better than it has. But when you orbit a planetary body that has lumpy gravity field, you use a lot of fuel.”

On Dec. 17 at about 5:28 EST, the spacecraft dubbed Ebb will undergo a controlled impact into a 2 km high “mountain, a rim of a crater that has been buried in ejecta near north pole of the Moon (coordinates are 75.62°N, 26.63°W). About 30 seconds later Flow will impact, about 40 km apart.

Both spacecraft will hit the surface at 3,760 mph (1.7 kilometers per second). No imagery of the impact is expected because the region will be in shadow at the time.

These maps of Earth’s moon highlight the region where the twin spacecraft of NASA’s Gravity Recovery and Interior Laboratory (GRAIL) mission will impact on Dec. Image credit: NASA/GSFC

Additionally, Gruber said that while they hope the Lunar Reconnaissance Orbiter will be able to observe the impact region (at the very least image the region both before and after impact), they don’t expect to there to be a “flash” visible from Earth, and do not believe there will be a significant chance of doing science by kicking up volatiles like LCROSS did, mostly because of the GRAIL spacecraft small size (each about the size of a washing machine) and because of the low angle of impact. The spacecraft have been at a low orbit averaging about 11 km above the surface this week, to be able to map at a high resolution before the fuel ran out.

They chose a mountain-side “since we’re coming in at angle of 1.5 degrees, it would only have left “skid marks” on level surface,” Zuber said. “There was interest in the team in impacting a structure, or a wall, so we could learn about mechanical properties of a crater rim. We’ll be looking at the rim of the crater and understanding how much is intact rock and how much is broken up. It will be very low probability but high scientific payoff if it works, if any volatiles they would be liberated from the impacts.”

The twist on this observation, Zuber said, is this crater is in sunlight most of the time, so if any volatiles come out, it would be surprising.

GRAIL project manager David Lehman said that Friday morning (December 14) the spacecraft will each be executing a maneuver will targeting the impact site, that will also position them to avoid what are called “historic heritage sites,” where the US and Russians have put soft landers on the Moon.

Then they’ll turn off the science instruments, followed by a series of engineering demonstrations to help with future missions over the weekend. About 54 minutes before impact, they’ll burn the remaining fuel to complete the last maneuver.

Lehman said there is a bit of challenge in hitting the crater rim. “We need to clear a ridge and then keep from going through a gap in the rim, because otherwise it would keep going and hit the far side of the Moon.”

Lehman added he was sad to see the mission end. “I’m kind of hoping tonight that a gas station will pull up to our spacecraft and refuel it.”

During their prime mission, from March through May, Ebb and Flow collected data while orbiting at an average altitude of 34 miles (55 kilometers). Their altitude was lowered to 14 miles (23 kilometers) for their extended mission, which began Aug. 30 and sometimes placed them within a few miles of the moon’s tallest surface features.

The duo’s successful prime and extended science missions generated the highest-resolution gravity field map of any celestial body. The map will provide a better understanding of how Earth and other rocky planets in the solar system formed and evolved.

“It is going to be difficult to say goodbye,” said Zuber. “Our little robotic twins have been exemplary members of the GRAIL family, and planetary science has advanced in a major way because of their contributions.”