Solar System Archives

December 17, 2014December 23, 2015 by Elizabeth Howell

New Pictures Of Philae’s Lonely Resting Spot On The Comet Emerge

This (in blue) is where the Philae lander came to rest on Comet 67P/Churyumov-Gerasimenko. The graphic is based on topographic modelling of the comet's nucleus and Philae's picture of a nearby cliff (in white). Credit: ESA/Rosetta/Philae/CNES/FD/CIVA

In scientific style, researchers are slowly narrowing down where the Philae lander arrived on Comet 67P/Churyumov-Gerasimenko. Earlier today (Dec. 17) at the American Geophysical Union meeting, more pictures from the European spacecraft were released showing its landing site and also what the terrain looked like underneath Philae as it bounced to its destination. The pictures were also placed on NASA’s website.

The lander is sleeping in a shady spot on the comet’s surface after the dramatic touchdown — actually, three touchdowns — on Nov. 12, when it flew for more than two hours across the surface and bounced as high as two miles (3.2 kilometers). This was partly because harpoons expected to secure it to the surface failed to deploy, and also because the comet crust was icier than expected, according to Gizmodo.

You can see in the diagram above Philae’s predicament; it’s wedged in a spot that doesn’t get a lot of sunlight, at least for now. That could change as 67P draws closer to the Sun in the late winter or early spring, but nobody yet knows for sure. And yes, the search for the landing site still continues in earnest, but the challenge now is the orbiting Rosetta spacecraft only has so much bandwidth to send back images, according to Wired. As more high-resolution OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) pictures arrive, scientists hope to figure out where it went.

Two pictures from Philae highlighted in today’s release are below. Will the lander take more? Scientists certainly hope so, but even if that doesn’t happen, the lander was only expected to return 20% of the science results in any case. Rosetta is still active and will stick with the comet through mid-2015, when 67P gets closest to the Sun.

The Philae lander captured a picture of a nearby cliff, nicknamed "Perihelion Cliff", on the nucleus of Comet 67P/Churyumov-Gerasimenko. Credit: ESA/Rosetta/Philae/CIVA — The Philae lander captured a picture of a nearby cliff, nicknamed “Perihelion Cliff”, on the nucleus of Comet 67P/Churyumov-Gerasimenko. Reports say this picture had been released before, but was processed to show more detail (such as the glare, believed to be reflection from the lander). Credit: ESA/Rosetta/Philae/CIVA

Philae's blurred view of the surface during its first bounce from Comet 67P/Churyumov-Gerasimenko on Nov. 12, 2014. The lander sailed for about two hours in the first bounce, made contact briefly, then bounced again before coming to rest. The black squares represent areas where data was not collected. Credit: ESA/Rosetta/Philae/CIVA — Philae’s blurred view of the surface during its first bounce from Comet 67P/Churyumov-Gerasimenko on Nov. 12, 2014. The lander sailed for about two hours in the first bounce, made contact briefly, then bounced again before coming to rest. The black squares represent areas where data was not collected. Credit: ESA/Rosetta/Philae/CIVA

December 17, 2014December 23, 2015 by Elizabeth Howell

Morning Star, We Hardly Knew Ya: Venus Express’ Best Discoveries In 8 Years

Artist's impression of Venus Express entering orbit in 2006. Credit: ESA - AOES Medialab

Venus Express is mostly dead. The spacecraft spent more than eight years faithfully relaying information from the Morning Star/Evening Star planet, but it’s now out of fuel, out of control and within weeks of burning up in the atmosphere.

While we mourn the end of the productive mission, the European Space Agency spacecraft showed us a lot about the planet that we once considered a twin to Earth. Some of the surprises, as you can see below, including a possibly slowing-down rotation, and the realization that volcanoes may still be active on the hellish planet.

False colour composite of a rainbow-like feature known as a ‘glory’, seen on Venus on 24 July 2011. The image is composed of three images at ultraviolet, visible, and near-infrared wavelengths from the Venus Monitoring Camera. The images were taken 10 seconds apart and, due to the motion of the spacecraft, do not overlap perfectly. The glory is 1200 km across, as seen from the spacecraft, 6000 km away. It's the only glory ever seen on another planet. Credit: ESA/MPS/DLR/IDA. — False color composite of a rainbow-like feature known as a ‘glory’, seen on Venus on 24 July 2011. The image is composed of three images at ultraviolet, visible, and near-infrared wavelengths from the Venus Monitoring Camera. The images were taken 10 seconds apart and, due to the motion of the spacecraft, do not overlap perfectly. The glory is 1200 km across, as seen from the spacecraft, 6000 km away. It’s the only glory ever seen on another planet. Credit: ESA/MPS/DLR/IDA.

Quick video summary: Venus Express found that the spacecraft’s rotation may have slowed down by 6.5 minutes between 1996 (when the Magellan spacecraft was in orbit) and 2012. The surprising information emerged when scientists discovered surface features weren’t in the expected areas, and couldn’t find any calculation errors between the data.

Animation of Venus’ southern polar vortex made from VIRTIS thermal infrared images; white is cooler clouds at higher altitudes. Credit: ESA/VIRTIS-VenusX/INAF-IASF/LESIA-Obs. de Paris (G. Piccioni, INAF-IASF)

Quick video summary: Volcanic flows may still be active on Venus’ surface, according to 2010 data from the mission. Scientists looked at surface areas that had not been “weathered” very much (indicating that they are relatively young) and detected at least nine spots where the heat in those zones is much higher than the areas around it.

Venus Express picture of clouds on the planet. Despite the planet being extremely hot, the spacecraft found a cold layer in the atmosphere at temperatures of about -175 degrees Celsius (-283 Fahrenheit) that is colder than anything on Earth. It's so chilling that carbon dioxide may freeze and fall as snow or ice. Credit: ESA/MPS/DLR/IDA — A picture of Venus’ clouds. Despite the planet being extremely hot, Venus Express found a cold layer in the atmosphere at temperatures of about -175 degrees Celsius (-283 Fahrenheit) that is colder than anything on Earth. It’s so chilling that carbon dioxide may freeze and fall as snow or ice. Credit: ESA/MPS/DLR/IDA

Artist's impression of Venus with the solar wind flowing around the planet, which has little magnetic protection. Venus Express found that a lot of water has bled into space over the years from the planet, which happens when the sun's ultraviolet radiation breaks oxygen and hydrogen molecules apart and pushes them into space. Credit: ESA - C. Carreau — Artist’s impression of Venus with the solar wind flowing around the planet, which has little magnetic protection. Venus Express found that a lot of water has bled into space over the years from the planet, which happens when the sun’s ultraviolet radiation breaks oxygen and hydrogen molecules apart and pushes them into space. Credit: ESA – C. Carreau

December 17, 2014December 23, 2015 by Elizabeth Howell

Gallery: Saturn Moons Show How Not To Be Seen In Cassini Images

Tethys is mostly obscured behind Rhea as the moons orbit Saturn. The picture was captured by the Cassini spacecraft in April 2012 and highlighted in December 2014. Credit: NASA/JPL-Caltech/Space Science Institute

Peekaboo! Tethys makes a (mostly in vain) attempt to hide behind Rhea in this picture taken by the Cassini spacecraft a couple of years ago, but highlighted by NASA in a recent picture essay. Besides the neat view of the orbital dance, one thing that is clearly visible between the two moons is the different colors — a product of their different surfaces. It turns out that Tethys’ bright surface is due to geysers from another moon.

“Scientists believe that Tethys’ surprisingly high albedo is due to the water ice jets emerging from its neighbor, Enceladus,” NASA stated. “The fresh water ice becomes the E ring [of Saturn] and can eventually arrive at Tethys, giving it a fresh surface layer of clean ice.”

Saturn has an astounding number of moons — 62 moons discovered so far, and 53 of them named, if you don’t count the spectacular ring that surrounds the planet. The collection of celestial bodies includes Titan, the second-biggest moon in the Solar System. It’s so big that it includes a thick atmosphere. (Ganymede, around Jupiter, is the biggest.)

Below are some other pictures of moons dancing around Saturn — some harder to spot than others. All images were taken by the Cassini spacecraft since it arrived at the planet in 2004.

Titan peeks from behind two of Saturn's rings. Another small moon Epimetheus, appears just above the rings. Credit: NASA/JPL/Space Science Institute — Titan peeks from behind two of Saturn’s rings. Another small moon Epimetheus, appears just above the rings. Credit: NASA/JPL/Space Science Institute

Saturn's moons Dione and Rhea appear conjoined in this optical illusion-like image taken by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute — Saturn’s moons Dione and Rhea appear conjoined in this optical illusion-like image taken by the Cassini spacecraft. Credit: NASA/JPL/Space Science Institute

Saturn's rings, made dark in part as the planet casts its shadow across them, cut a striking figure before Saturn's largest moon, Titan. Credit: NASA/JPL/Space Science Institute — Saturn’s rings, made dark in part as the planet casts its shadow across them, cut a striking figure before Saturn’s largest moon, Titan. Credit: NASA/JPL/Space Science Institute

Three of Saturn's moons bunch together in this image by Cassini. Credit: NASA/JPL/Space Science Institute. Click for larger image. — Three of Saturn’s moons bunch together in this image by Cassini. Credit: NASA/JPL/Space Science Institute. Click for larger image.

Saturns rings with Saturns moon Mimas in the foreground (credit: NASA) — Saturn’s rings with Saturn’s moon Mimas in the foreground (credit: NASA)

Titan and Tethys line up for a portrait of 'sibling' moons. Credit: NASA/JPL/Space Science Institute — Titan and Tethys line up for a portrait of ‘sibling’ moons. Credit: NASA/JPL/Space Science Institute

December 17, 2014December 23, 2015 by Elizabeth Howell

How Many Horses Can A Rocket Carry? Cool Comic Comparison

An xkcd comic from December 2014 showing spacecraft mass and launch vehicle capacity in terms of horses. The full comic is at http://xkcd.com/1461/large/. Credit: xkcd

The challenge with thinking about space is putting it into terms that we can understand. How far is a light-year? Just how powerful is NASA’s next-generation Space Launch System, which the agency hopes will bring astronauts out into the solar system?

Luckily for us, the comic xkcd is a regular contributor to making space understandable, and the latest comic from Randall Munroe is a gem — explaining launch vehicle capacity and spacecraft mass in terms of horses.

So now comparisons are fairly easy. At the left of the diagram, for example, you can see the Saturn V — that rocket that was the first stage of bringing astronauts to the moon in the 1960s — carried the equivalent of 262 horses. The SLS Block 2, if it is ever developed, will have a slightly larger capacity of 289 horses.

Blastoff of NASA’s Space Launch System (SLS) rocket and Orion crew vehicle from the Kennedy Space Center, Florida. Credit: NASA/MSFC

Meanwhile, the spacecraft mass of the International Space Station is an astounding 932 horses, the total shuttle mass was 206 horses, and Apollo was 67 horses. There also are a few robotic spacecraft in there, such as Voyager, Vanguard 1, the Keyhole 3 spy satellite, and the upcoming James Webb Space Telescope.

Check out the entire diagram in large here, and the original comic here. (For those unfamiliar with xkcd, make sure to mouse over the comic for an extra joke.)

December 16, 2014December 23, 2015 by Elizabeth Howell

Venus Express Out Of Gas; Mission Concludes, Spacecraft On Death Watch

Artist's conception of Venus Express. Image credit: ESA

After surviving an eight-year mission and a daring plunge into part of the atmosphere of Venus, a plucky spacecraft orbiting the hothouse planet is finished its mission, the European Space Agency declared. Venus Express can no longer communicate consistently with Earth. The spacecraft itself will fall into the atmosphere and likely be destroyed in the coming weeks.

“The available information provides evidence of the spacecraft losing attitude control,” stated Patrick Martin, ESA’s Venus Express mission manager, who added it was because the machine exhausted its fuel as controllers tried to raise it to a more stable altitude above Venus.

The demise of the mission, in a sense, began when controllers chose to bring Venus Express into the atmosphere this summer. The goal was not only to learn more about Venus, but also to get information on how future spacecraft could “surf” the atmosphere when, say, landing on the planet.

Artist's conception of Venus Express doing an aerobraking maneuver in the atmosphere in 2014. Credit: ESA–C. Carreau — Artist’s conception of Venus Express doing an aerobraking maneuver in the atmosphere in 2014. Credit: ESA–C. Carreau

The orbit was reduced to about 130 km to 135 km (80.7 miles to 83.9 miles) above the planet at its lowest approach, which took place in earnest between June 18 and July 11. Controllers then did 15 small thruster burns, which raised the spacecraft’s minimum altitude to 460 km (286 miles).

But it wasn’t a stable orbit, with the spacecraft continuing to spiral into the planet as gravity pulled it down. ESA decided to again try raising the spacecraft’s altitude between Nov. 23 and Nov. 30, but lost consistent contact with the spacecraft Nov. 28. It appears Venus Express is out of gas, the agency said.

It’s hard to know exactly when the spacecraft will die, but it serves as a good example of how space recycling can end up making an interesting mission. The design and some of the instruments on Venus Express were based upon those used for other missions, particularly Mars Express and Rosetta. And the lessons of the spacecraft will certainly be used in future missions.

Tomorrow, we’ll run down some of the highlights of the mission.

Source: European Space Agency

December 16, 2014December 23, 2015 by Elizabeth Howell

XPRIZE Moon Robot Contest Deadline Pushed Back A Year To 2016

For the 18 teams racing to put a robot on the Moon, some good news — they have an extra year to get the job done. Citing the groups’ difficulty in technology and raising money, the Google Lunar XPRIZE competition said the teams will now have until Dec. 31, 2016 to accomplish their missions.

The challenge was first announced in 2007 and the number of teams has stayed fairly steady since at least 2010, when 21 teams were reported in a Universe Today story. Some of the groups are competing for milestone prizes, the latest of which will be announced Jan. 15.

Astrobiotic won two previous competitions for $500,000 (in mobility) and $250,000 (for imaging). The grand prize is still open to everybody, regardless if they choose to pursue the milestone prizes.

“We know the mission we are asking teams to accomplish is extremely difficult and unprecedented, not only from a technological standpoint, but also in terms of the financial considerations,” stated Robert Weiss, XPRIZE’s vice-chairman and president.

“It is for this reason that we have decided to extend the competition timeline. We firmly believe that a whole new economy around low-cost access to the Moon will be the result of the Google Lunar XPRIZE.”

While the deadline has been extended, the goal is the same: the winning team must ferry a robotic machine to the Moon, move 500 meters (1,640 feet) somehow (on, above or below the surface) and send two “mooncasts” back to Earth. In 2013, Weiss told Universe Today that some of the teams had signed launch contracts, but declined to provide many details due to confidentiality concerns.

You can see more details about the teams and their progress on the XPRIZE website. The grand prize is $20 million and there is an additional $10 million available in other prizes.

December 16, 2014December 23, 2015 by Elizabeth Howell

Name That Crater On Mercury! MESSENGER Team Opens Public Contest

The crater Scarlatti (at center) shines clearly in this image of Mercury taken by the MESSENGER spacecraft. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

Here’s your rare chance to leave a lasting mark on a piece of the Solar System. The team behind the MESSENGER spacecraft — that machine orbiting Mercury since 2011 — is asking the public to help them name craters on the planet, in an open contest.

Fifteen finalists will be forwarded to the official arbitrator of astronomical names on Earth, the International Astronomical Union, which will pick five names in time for the end of the MESSENGER mission this spring.

“This brave little craft, not much bigger than a Volkswagen Beetle, has travelled more than 8 billion miles [12.8 billion kilometers] since 2004—getting to the planet and then in orbit,” stated Julie Edmonds of the Carnegie Institution for Science, who leads the MESSENGER education and public outreach team.

A crater on Mercury at the edge of the larger Oskison crater located in the plains north of Caloris basin. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington

“We would like to draw international attention to the achievements of the mission and the guiding engineers and scientists on Earth who have made the MESSENGER mission so outstandingly successful.”

Here are some guidelines to increase your chances of success:
– Make sure the name does not have significance politically, religiously or for the military;
– Focus on names of writers, artists and composers and research them thoroughly, as you will be expected to provide a justification;
– Don’t pick a name that has been used elsewhere in the Solar System.

Mercury's southern polar region as seen from MESSENGER. (Credit: NASA/Johns Hopkins UniversityApplied Physics Laboratory/Carnegie Institution of Washington). — Mercury’s southern polar region as seen from MESSENGER. (Credit: NASA/Johns Hopkins UniversityApplied Physics Laboratory/Carnegie Institution of Washington).

Some additional hints come from the official contest website, which adds that the competition is open to everyone except MESSENGER’s education and public outreach team and that entries close Jan. 15.

Impact craters are named in honor of people who have made outstanding or fundamental contributions to the Arts and Humanities (visual artists, writers, poets, dancers, architects, musicians, composers and so on). The person must have been recognized as an art-historically significant figure for more than 50 years and must have been dead for at least three years. We are particularly interested in submissions that honor people from nations and cultural groups that are under-represented amongst the currently-named craters.

This isn’t the first planet with recent open invitations for the public to name craters. Earlier this year, astronomy education group Uwingu began asking for suggestions to name craters on Mars for maps that will be used by the Mars One team as it plans to land a private crewed mission on the planet in the coming years. Those names, however, will likely not be recognized by the IAU (the official statement is here.)

December 16, 2014December 23, 2015 by Elizabeth Howell

Robotic Moon Lander Concept Raises $942K, Meeting Goal With A Day To Go

Artist's conception of Lunar Mission One's robotic lander touching down on the surface. Credit: Lunar Missions Ltd.

Update, Dec. 18, 8:09 a.m. EST: Lunar Mission One closed its fundraising mission the night before at £672,447 ($1,052,413), short of its stretch goal of £700,000.

With just over a day to go in their crowdfunding campaign, a British group hoping to put a robotic lander on the moon in 2024 reached their fundraising goal of $932,000 (£600,000) overnight.

The money is supposed to move the project into more concrete phases after the founders spent seven years quietly developing their concept, but many of the details about the design and funding have yet to be unveiled.

“We plan to send an unmanned robotic landing module to the South Pole of the Moon – an area unexplored by previous missions,” the mission says on its Kickstarter page. “We’re going to use pioneering technology to drill down to a depth of at least 20m – 10 times deeper than has ever been drilled before – and potentially as deep as 100m.

“By doing this,” the statement adds, “we will access lunar rock dating back up to 4.5 billion years to discover the geological composition of the Moon, the ancient relationship it shares with our planet and the effects of asteroid bombardment. Ultimately, the project will improve scientific understanding of the early Solar System, the formation of our planet and the Moon, and the conditions that initiated life on Earth.”

Artist's conception of a moon drill that could potentially be used by Lunar Mission One's lunar lander. Credit: Lunar Missions Ltd. — Artist’s conception of a moon drill that could potentially be used by Lunar Mission One’s lunar lander. Credit: Lunar Missions Ltd.

“Stretch goals” for the organization include rewards for backers such as an e-commerce program, a massive open online course for educational purposes, a party for backers in London, and being “a leading role” in World Space Week 2015. The additional money, however, will also be used for drilling studies, putting together the science team and making a work plan.

With the money raised, the project now has the ambitious target of getting their lander on the moon by 2024. According to the schedule, the main mission contract should be awarded by 2017, design and development begins by 2018, and the final build commences in 2021.

RAL Space (which assisted with the Philae comet landing and 200 other space missions, according to the page) is serving as a technical advisor to the board. The project chair of Lunar Missions Ltd. (which is responsible for the project) is Ian Taylor, a former United Kingdom government science minister and co-chair of the parliamentary space committee.

As with other private ventures in space such as Mars One, however, Lunar Mission One is dealing with long timelines, a risky goal and a not-certain guarantee of success.

December 15, 2014December 23, 2015 by Ken Kremer

NASA and SpaceX targeting Dec. 19 for next Space Station Launch

SpaceX Falcon 9 erect at Cape Canaveral launch pad 40 awaiting launch on Sept 20, 2014 on the CRS-4 mission. Credit: Ken Kremer - kenkremer.com

NASA and SpaceX are now targeting Dec. 19 as the launch date for the next unmanned cargo run to the International Space Station (ISS) under NASA’s Commercial Resupply Services contract.

The fifth SpaceX cargo mission was postponed from Dec. 16 to Dec. 19 to “allow SpaceX to take extra time to ensure they do everything possible on the ground to prepare for a successful launch,” according to a statement from NASA.

The Dragon spacecraft will launch atop a SpaceX Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida.

Both the Falcon 9 rocket and its Dragon spacecraft are in good health, according to NASA.

The mission dubbed SpaceX CRS-5 is slated for liftoff at 1:20 p.m.

An on time liftoff will result in a rendezvous with the ISS on Sunday. The crew would grapple the Dragon with the stations 57 foot long robotic arm at about 6 a.m.

The SpaceX Dragon capsule is snared by the International Space Station's Canadarm 2. Credit: NASA — The SpaceX Dragon capsule is snared by the International Space Station’s Canadarm 2. Credit: NASA

US astronaut and station commander Barry Wilmore will operate the Canadarm2 to capture the SpaceX Dragon when it arrives Sunday morning. ESA astronaut Samantha Cristoforetti will assist Wilmore working at a robotics workstation inside the domed Cupola module during the commercial craft’s approach and rendezvous.

The unmanned cargo freighter is loaded with more than 3,700 pounds of scientific experiments, technology demonstrations, crew supplies, spare parts, food, water, clothing and assorted research gear.

The Dragon research experiments will support over 256 science and research investigations for the six person space station crews on Expeditions 42 and 43.

Among the payloads is the Cloud-Aerosol Transport System (CATS), a remote-sensing laser instrument to measure clouds and the location and distribution of pollution, dust, smoke, and other particulates and aerosols in the atmosphere.

A secondary objective of SpaceX is to attempt to recover the Falcon 9 first stage on an off shore barge.

The SpaceX CRS-4 mission to the ISS concluded with a successful splashdown on Oct 25 after a month long stay.

The SpaceX CRS-5 launch is the first cargo launch to the ISS since the doomed Orbital Sciences Antares/Cygnus launch ended in catastrophe on Oct. 28.

With Antares launches on indefinite hold, the US supply train to the ISS is now wholly dependent on SpaceX.

Orbital Sciences has now contracted United Launch Alliance (ULA) to launch the firms Cygnus cargo freighter to the ISS by late 2015 on an Atlas V rocket.

December 15, 2014December 23, 2015 by Elizabeth Howell

Martian Teardrop: Here’s How The Sun Moves Over A Red Planet Year

The Opportunity rover captured this analemma showing the Sun's movements over one Martian year. Images taken every third sol (Martian day) between July, 16, 2006 and June 2, 2008. Credit: NASA/JPL/Cornell/ASU/TAMU

Stand in the same spot every day. Take a picture of the Sun. What happens? Slowly, you see our closest star shifting positions in the sky. That motion over an entire year is called an analemma. The Opportunity rover on Mars even captured one on the Red Planet, which you can see above, and it’s a different shape than what you’ll find on Earth.

An April Astronomy Picture of the Day post (highlighted this weekend on Reddit) explains that Earth’s analemma of the Sun is figure-8-shaped, while that on Mars looks somewhat like a pear (or a teardrop, we think.) The Earth and Mars each have about the same tilt in their orbit — that same tilt that produces the seasons — but the orbit of Mars is more elliptical (oval) than that of Earth.

An analemma of the Sun, taken from Budapest, Hungary over a one year span. (Courtesy of György Soponyai, used with permission).

“When Mars is farther from the Sun, the Sun progresses slowly in the martian sky creating the pointy top of the curve,” the APOD post stated. “When close to the Sun and moving quickly, the apparent solar motion is stretched into the rounded bottom. For several sols some of the frames are missing due to rover operations and dust storms.”

The picture you see at the top of the post was taken every third sol (or Martian day, which is 24 hours and 37 minutes) between July 2006 and June 2008. The landscape surrounding the analemma is from Victoria Crater, where Opportunity was roaming at that time. (The rover is now on the rim of Endeavour Crater, still trucking after nearly 11 full years on the surface.)

In 2006, APOD also published a simulated analemma from Sagan Memorial Station, the landing site of the Sojourner spacecraft and tiny Pathfinder rover. In this case, the simulation showed the Sun’s movements every 30 sols. A Martian year is 668 sols.

You can read more details about analemmae in this past Universe Today post by David Dickinson, which relates the phenomenon to the passage of time.