Spectacular Views: The Moon Occults Jupiter

Caption: July 15 2012 occultation, taken with Canon 550D on Newton 200/1200 mounted on NEQ6Pro. Credit: Andrei Juravle

Astrophotographers in Northern Africa, Europe and the Middle East were treated to a beautiful sight in the early morning hours of July 15, 2012. A lunar occultation of Jupiter took place just before dawn, as the waning crescent Moon slid in front of the planet Jupiter. Venus was hanging around nearby, too. Several astrophotographers were able to capture the event, and some got a bonus look at Jupiter’s Galilean moons, as well! Above is a lovely image by Andrei Juravle.

More below!

Caption: The Moon, Venus and Jupiter. Credit Thierry Legault.

Astrophotographer extraordinaire Thierry Legault took this great shot of Venus, Jupiter and the Moon from Saint-Cloud, France with a Canon 5D mark II and 135mm lens. But look closely: the satellites of Jupiter are visible:

Caption: A closer look reveals Jupiter’s moons! Credit: Thierry Legault.

And as always, you should check out Thierry’s website for more incredible images.

Caption: Jupiter and the Moon hover over Dolmabahce Mosque in Istanbul, Turkey. Credit: Rasid Tugral.

Caption: Clouds nearly covered the view in Mombaroccio, Marche, Italy. Credit: Niki Giada.


Caption: A series of images of the Moon’s occultation of Jupiter as seen in Saida, Lebanon. Credit: astroZ1 on Flickr.


Caption: Occultation of Jupiter by the Moon as seen from Smolyan, Bulgaria. Credit: Zlatan Merakov.

More images are still coming in, and you can see more on Universe Today’s Flickr page. Thanks to everyone who submitted their gorgeous images!

Fifth Moon Found Around Pluto

This just in! Astronomers working with the Hubble Space Telescope have spotted a new moon around distant Pluto, bringing the known count up to 5. The image above was released by NASA just minutes ago, showing the Pluto system with its newest member, P5.

This news comes just a couple of weeks shy of the one-year anniversary of the announcement of Pluto’s 4th known moon, still currently named “P4”.

The news was shared this morning by an undoubtedly excited Alan Stern of the Southwest Research Institute (SwRI) on Twitter.

Astronomers estimate P5 to be between 6 and 15 miles (9.6 to 24 km) in diameter. It orbits Pluto in the same plane as the other moons — Charon, Nix, Hydra and P4.

“The moons form a series of neatly nested orbits, a bit like Russian dolls,” said team lead Mark Showalter of the SETI Institute.

A mini-abstract of an upcoming paper lists image sets acquired on 5 separate occasions in June and July. According to the abstract, P5 is 4% as bright as Nix and 50% as bright as P4.

The satellite’s mean magnitude is V = 27.0 +/- 0.3, making it 4 percent as bright as Pluto II (Nix) and half as bright as S/2011 (134340) 1. The diameter depends on the assumed geometric albedo: 10 km if p_v = 0.35, or 25 km if p_v =0.04. The motion is consistent with a body traveling on a near-circular orbit coplanar with the other satellites. The inferred mean motion is 17.8 +/- 0.1 degrees per day (P = 20.2 +/- 0.1 days), and the projected radial distance from Pluto is 42000 +/- 2000 km, placing P5 interior to Pluto II (Nix) and close to the 1:3 mean motion resonance with Pluto I (Charon).

The new detection will help scientists navigate NASA’s New Horizons spacecraft through the Pluto system in 2015, when it makes an historic and long-awaited high-speed flyby of the distant world.

See the news release from NASA here.

(H/T to Ray Sanders at DearAstronomer.com)

Top image: NASA, ESA and M. Showalter (SETI Institute)

Surprising Swirls Above Titan’s South Pole

View of Titan's South Pole, showing a vortex. Credit: NASA

Thanks to Cassini’s new vantage point granted by its inclined orbit researchers have gotten a new look at the south pole of Titan, Saturn’s largest moon. What they’ve recently discovered is a swirling vortex of gas forming over the moon’s pole, likely the result of the approach of winter on Titan’s southern hemisphere.

What we’re seeing here is thought to be an open cell convection process in Titan’s upper atmosphere. In open cells, air sinks in the center of the cell and rises at the edge, forming clouds at cell edges. However, because the scientists can’t see the layer underneath the layer visible in these new images, they don’t know what other mechanisms may be at work.

A stable atmospheric event that’s found here on Earth as well, open cell convection can be compared to the action of boiling water.

Titan has already been seen to have a thicker area of high-altitude haze over its north pole, and as autumn progresses toward winter in Titan’s south during the course of Saturn’s 29.7-year-long orbit this may very well be the beginnings of a southern polar hood.

An animation of this southern vortex can be found here.

“We suspect that this maelstrom, clearly forming now over the south pole and spinning more than forty times faster than the moon’s solid body, may be a harbinger of what will ultimately become a south polar hood as autumn there turns to winter.  Of course, only time will tell.”

– Carolyn Porco, Cassini Imaging Team Leader

Discoveries like this are prime examples of why it was so important for Cassini to have an extended, long-duration mission around Saturn, so that seasonal changes in the planet and moons could be closely observed. New seasons bring new surprises!

The southern vortex structure was also captured in raw images acquired by Cassini on June 28. A color-composite made from three of those raw images is below (the vortex can be seen at center just right of the terminator):

You can find more images from Cassini on the CICLOPS Imaging Team site.

Image credits: NASA/JPL/Space Science Institute. Bottom RGB composite by Jason Major.

Kickstart Your DNA (And a Rover) To The Moon!


Omega Envoy, the non-profit research lab Earthrise Space, Inc.’s team competing for the Google Lunar X PRIZE, has launched a Kickstarter project to help fund a 4-axis CNC milling machine needed to continue development on their proposed lunar rover. CNC machines don’t come cheap, but in typical Kickstarter fashion Earthrise Space is offering incremental rewards to anyone who donates to their project — from mentions on their site to t-shirts, Moon globes and facility tours (and even 5-gallon tubs of duck sauce) and, if you’re lucky enough to have deep pockets and a desire to help a student training ground get their designs off the ground, you can even have your DNA sent to the Moon!

From the Google Lunar X PRIZE article:

For the first time in human history, individuals will have the opportunity to send a sample of their DNA to the lunar surface. For a pledged donation of $10,000 or more, ESI will collect your DNA sample, package it into a storage container mounted on the company’s Lunar Descent Vehicle and fly it to the surface of the moon where it will be preserved for all time.

“We are excited to be exploring new approaches for fundraising and for public engagement, including through the crowdsourcing Kickstarter platform,” said ESI’s Chief Operating Officer (COO) Joseph Palaia. “We are hopeful that this Kickstarter project helps us to make significant progress towards our near-term fundraising goals, while also providing some incredible rewards for our supporters.”

With the Google Lunar X PRIZE, a total of $30 million in prize money is available to the first privately funded team to safely land a robot on the surface of the Moon, have that robot travel 500 meters over the surface, and send HD video, images and data back to Earth.

Of the 26 teams in the competition, ESI is one of only six teams which have been selected for a NASA Innovative Lunar Demonstrations Data contract worth up to $10M. But the contract is awarded incrementally and a multi-axis CNC machine is needed to take their designs to the next level (and meet upcoming contract goals.) Donate to their Kickstarter project here.

At whatever level you contribute, know that you are helping students build real spacecraft, and you’re going to be getting some pretty amazing rewards as well! The students appreciate your support!

— Omega Envoy team, ESI

Find out more about ESI’s project on the Earthrise Space Inc. website, and check out the other Google Lunar X PRIZE competitors here.

Source: Google Lunar X PRIZE blog

An Epic Crater Called Odysseus

On June 28 NASA’s Cassini spacecraft passed by Tethys, a 1,062-kilometer (662-mile) -wide moon of Saturn that’s made almost entirely of ice. Tethys is covered in craters of all sizes but by far the most dramatic of all is the enormous Odysseus crater, which spans an impressive 450 kilometers (280 miles) of the moon’s northern hemisphere — nearly two-fifths of its entire diameter!

In fact, whatever struck Tethys in the distant past probably should have shattered it into pieces… but didn’t.

Tethys likely held itself together because when the impact occurred that formed Odysseus, the moon was still partially molten. It was able to absorb some of the energy of the impact and thus avoid disintegration — although it was left with a quite the battle scar as an eternal reminder.

The images below are raw images from Cassini’s latest pass of Tethys, showing the moon’s rugged terrain and portions of Odysseus from a distance of 68,521 kilometers (42,577 miles).

The central peak of Odysseus has collapsed, leaving a depression — another indication that the moon wasn’t entirely solid at the time of impact.

Tethys orbits Saturn at a distance of 294,660 kilometers (183,100 miles), about 62,000 miles closer than the Moon is from Earth. Such a close proximity to Saturn subjects Tethys to tidal forces, the frictional heating of which likely helped keep it from cooling and solidifying longer than more distant moons. As a result Tethys appears somewhat less cratered than sister moons Rhea and Dione, which still bear the marks of their earliest impacts… although looking at the region south of Odysseus it’s hard to image a more extensively-cratered place.

Tethys is just another reminder of the violent place our solar system can be. Find out more about Tethys on the Cassini mission site here.

Image credits: NASA/JPL/Space Science Institute. Edited by J. Major. Images have not been calibrated or validated, and each has been level-adjusted and sharpened to bring out surface detail, and in some areas deinterlacing was used to remove linear raw image artifacts.

Rivers of Rock

The Moon may not have ever had liquid water on its surface — despite the use of the term mare, Latin for “sea” and moniker for the large regions of darker material visible from Earth — but liquid did indeed flow on the Moon in ages past… liquid rock, briefly set loose by the impacts that formed its ubiquitous craters.

When large meteorites impacted the Moon, crust at the site would melt and get flung outwards, flowing downhill as rivers of rock and creating streams and pools of melted material before cooling and solidifying. There the rivers would remain, a permanently-hardened testament to the event that made them.

The image above, part of a NAC scan acquired by NASA’s Lunar Reconnaissance Orbiter on March 9, shows a solidified melt flow dating back to the creation of Tycho crater approximately 108 million years ago –which may sound like a long time but it’s actually very recent for large-scale lunar features.

The flow is interrupted by a younger, 400-meter-wide crater that impacted the lunar surface along its length. Since it punches through the melt flow as well as the local surface, it would be a great place for future astronaut geologists to explore!

Taken under slightly different lighting conditions, the image below shows a large melt pond that the flow above terminates in. The pond is about 4500 meters long by 2100 meters across (2.8 x 1.3 miles).

Such images wouldn’t be possible without the awesome Lunar Reconnaissance Orbiter. Launched on June 18, 2009, LRO explores the lunar surface from an altitude of only 50 km (31 miles). Read more on the LRO site here.

Image credits: NASA/GSFC/Arizona State University

Loads of Ice Waiting for Explorers at the Moon’s Shackleton Crater

Shackleton crater on the Moon’s south pole has been somewhat of an enigma, as its permanently shadowed interior has made it difficult to detect what is inside. But with new observations using the laser altimeter on the Lunar Reconnaissance Orbiter (LRO) spacecraft, a team of researchers has essentially illuminated the crater’s interior with laser light, measuring its albedo, or natural reflectance. The scientists found that the crater’s floor is quite bright, an observation consistent with the presence of ice. In fact, ice may make up 22 percent of the material on the crater floor, with possibly more ice embedded within the crater walls.

“We decided we would study the living daylights out of this crater,” said Maria Zuber from the Massachuesetts Institute of Technology, who lead a team to study Shackleton Crater. “From the incredible density of observations we were able to make an extremely detailed topographic map.”

For laser altimeter observations, elevation maps can be created by measuring the time it takes for laser light to bounce down to the Moon’s surface and back to the instrument. The longer it takes, the lower the terrain’s elevation. Using these measurements, the group mapped the crater’s floor and the slope of its walls.

The team used over 5 million measurements to create their detailed map.


While the crater’s floor was relatively bright, Zuber and her colleagues observed that its walls were even brighter. The finding was at first puzzling. Scientists had thought that if ice were anywhere in a crater, it would be on the floor, where no direct sunlight penetrates. The upper walls of Shackleton crater are occasionally illuminated, which could evaporate any ice that accumulates. A theory offered by the team to explain the puzzle is that “moonquakes”– seismic shaking brought on by meteorite impacts or gravitational tides from Earth — may have caused Shackleton’s walls to slough off older, darker soil, revealing newer, brighter soil underneath. Zuber’s team’s ultra-high-resolution map provides strong evidence for ice on both the crater’s floor and walls.

“There may be multiple explanations for the observed brightness throughout the crater,” said Zuber. “For example, newer material may be exposed along its walls, while ice may be mixed in with its floor.”

The crater, named after the Antarctic explorer Ernest Shackleton, is nearly 20 km (more than 12 miles) wide and over 3 km (2 miles) deep — about as deep as Earth’s oceans. Zuber described the crater’s interior as “extremely rugged … It would not be easy to crawl around in there.”

She added that the new topographic map will help researchers understand crater formation and study other uncharted areas of the moon.

“I will never get over the thrill when I see a new terrain for the first time,” Zuber said. “It’s that sort of motivation that causes people to explore to begin with. Of course, we’re not risking our lives like the early explorers did, but there is a great personal investment in all of this for a lot of people.”

Ben Bussey, staff scientist at Johns Hopkins University’s Applied Physics Laboratory, said the new evidence for ice in Shackleton crater may indeed help determine the course for future lunar missions.

“Ice in the polar regions has been sort of an enigmatic thing for some time … I think this is another piece of evidence for the possibility of ice,” Bussey says. “To truly answer the question, we’ll have to send a lunar lander, and these results will help us select where to send a lander.”

And for any humans explorers, a crater like Shackleton at the lunar poles may well be the best location for a base, as the poles contain regions of near-permanent sunlight needed for power, and regions of near-permanent darkness containing ice — both of which would be essential resources for any lunar colony.

The team’s research was published today in the Journal Nature.

Sources: MIT, NASA

Lead image caption: Elevation (left) and shaded relief (right) image of Shackleton, a 21-km-diameter (12.5-mile-diameter) permanently shadowed crater adjacent to the lunar south pole. The structure of the crater’s interior was revealed by a digital elevation model constructed from over 5 million elevation measurements from the Lunar Orbiter Laser Altimeter. Credit: NASA/Zuber, M.T. et al., Nature, 2012

Second image caption: This is an elevation map of Shackleton crater made using LRO Lunar Orbiter Laser Altimeter data. The false colors indicate height, with blue lowest and red/white highest. Credit: NASA/Zuber, M.T. et al., Nature, 2012

Is It Time to Return to the Moon?

Should we pay another visit to the Moon? (From "Le Voyage Dans La Lune" by Georges Méliès, 1902)

Humans haven’t set foot on the Moon — or any other world outside of our own, for that matter — since Cernan and Schmitt departed the lunar surface on December 14, 1972. That will make 40 years on that date this coming December. And despite dreams of moon bases and lunar colonies, there hasn’t even been a controlled landing there since the Soviet Luna 24 sample return mission in 1976 (not including impacted probes.) So in light of the challenges and costs of such an endeavor, is there any real value in a return to the Moon?

Some scientists are saying yes.

Researchers from the UK, Germany and The Netherlands have submitted a paper to the journal Planetary and Space Science outlining the scientific importance of future lunar surface missions. Led by Ian A. Crawford from London’s Birkbeck College, the paper especially focuses on the value of the Moon in the study of our own planet and its formation, the development of the Earth-Moon system as well as other rocky worlds  and even its potential contribution in life science and medicinal research.

Even though some research on the lunar surface may be able to be performed by robotic missions, Crawford et al. ultimately believe that “addressing them satisfactorily will require an end to the 40-year hiatus of lunar surface exploration.”

The team’s paper outlines many different areas of research that would benefit from future exploration, either manned or robotic. Surface composition, lunar volcanism, cratering history — and thus insight into a proposed period of “heavy bombardment” that seems to have affected the inner Solar System over 3.8 billion years ago — as well as the presence of water ice could be better investigated with manned missions, Crawford et al. suggest.

(Read: A New Look At Apollo Samples Supports Ancient Impact Theory)

In addition, the “crashed remains of unsterilized spacecraft” on the Moon warrant study, proposes Crawford’s team. No, we’re not talking about alien spaceships — unless the aliens are us! The suggestion is that the various machinery we’ve sent to the lunar surface since the advent of the Space Age may harbor Earthly microbes that could be returned for study after decades in a lunar environment. Such research could shed new light on how life can — or can’t — survive in a space environment, as well as how long such “contaminants” might linger on another world.

Crawford’s team also argues that only manned missions could offer all-important research on the long-term effects of low-gravity environments on human physiology, as well as how to best sustain exploration crews in space. If we are to ever become a society with the ability to explore and exist beyond our own planet, such knowledge is critical.

And outside of lunar exploration itself, the Moon offers a place from which to perform deeper study of the Universe. The lunar farside, shielded as it is from radio transmissions and other interference from Earth, would be a great place for radio astronomy — especially in the low-frequency range of 10-30 MHz, which is absorbed by Earth’s ionosphere and is thus relatively unavailable to ground-based telescopes. A radio observatory on the lunar farside would have a stable platform from which to observe some of the earliest times of the Universe, between the Big Bang and the formation of the first stars.

Of course, before anything can be built on the Moon or retrieved from its surface, serious plans must be made for such missions. Fortunately, says Crawford’s team, the 2007 Global Exploration Strategy — a framework for exploration created by 13 space agencies from around the world — puts the Moon as the “nearest and first goal” for future missions, as well as Mars and asteroids. Yet with subsequent budget cuts for NASA (a key player for many exploration missions) when and how that goal will be reached still remains to be seen.

See the team’s full paper on arXiv.org here, and check out a critical review on MIT’s Technology Review.

“…this long hiatus in lunar surface exploration has been to the detriment of lunar and planetary science, and indeed of other sciences also, and that the time has come to resume the robotic and human exploration of the surface of the Moon.”

— Ian A. Crawford,  Department of Earth and Planetary Sciences, Birkbeck College, UK

 Top image from “Le Voyage Dans La Lune” by Georges Méliès, 1902. Second image: First photo of the far side of the Moon, acquired by the Soviet Luna-3 spacecraft on Oct. 7, 1959.

On the Edge of Titan

Titan's haze-covered limb seen by Cassini on June 6

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Here’s a quick look at one of my favorite cosmic photo subjects – the varying layers of atmosphere that enshroud Saturn’s enormous moon Titan. The image above is a color-composite made from three raw images acquired by Cassini during its latest flyby.

On June 7 Cassini approached Titan within 596 miles (959 km) and imaged portions of the moon’s northwest quadrant with its radar instrument, as well as conducted further investigations of areas near the equator where surface changes were detected in 2010.

The image here was assembled from three raw images captured in red, green and blue visible light channels. It reveals some structure in the upper hydrocarbon haze layers that extend upwards above the moon’s opaque orange clouds — reaching 400-500 km in altitude, Titan’s atmosphere is ten times thicker than Earth’s!

The June 6 flyby was the second in a series of passes that will take Cassini into a more inclined orbit, where it will reside for the next three years as it investigates Saturn’s polar regions and obtains better views of its ring system.

Read more about the flyby here.

Image: NASA/JPL/Space Science Institute. Composite by J. Major.

Timelapse of a Moonrise as Seen from the ISS

Astronaut Don Pettit continues to ‘wow’ us all with his photographic exploits. In this great timelapse video, not only does Pettit capture a stunning Moonrise over Earth, but he had the presence of mind to set up his video camera in such way that he could also show himself opening the shutters in the space station’s Cupola observation windows just in time to watch all the action. The time-lapse scene was photographed from the airlock of the ISS’s Russian segment.