Comet 67P/Churyumov-Gerasimenko imaged by OSIRIS on July 29, 2014
WOW! We’re really getting to the good stuff now! This is no computer-generated shape model, this is the real deal: the double-lobed nucleus of Comet 67P/C-G, as imaged by Rosetta’s OSIRIS (Optical, Spectroscopic, and Infrared Remote Imaging System) narrow-angle camera on Tuesday, July 29. At the time just about a week away from making its arrival, ESA’s spacecraft was 1,950 km (1,211 miles) from the comet when this image was taken. (That’s about the distance between Providence, Rhode Island and Miami, Florida… that’s one fancy zoom lens, Rosetta!)
Comet 67P/Churyumov-Gerasimenko imaged on July 14, 2014 by OSIRIS from a distance of approximately 12,000 km. (ESA)
This latest image reveals some actual surface features of the 4-km-wide comet, from a few troughs and mounds to the previously-noted bright band around the “neck” connecting the two lobes. The resolution in the July 29 OSIRIS image is 37 meters per pixel.
Since Rosetta is quickly closing the gap between itself and the comet we can only expect better images to come in the days ahead, so stay tuned — this is going to be an exciting August!
Keep up with the latest news on ESA’s Rosetta blog here, and find out where exactly Rosetta and Comet 67P/C-G are in the Solar System here.
It was a daring maneuver, but the plan to put Venus Express lower in the planet’s thick atmosphere has worked. For the past month, the European Space Agency steered the long-running spacecraft to altitudes as low as 81 miles (131 kilometers) for a couple of minutes at a time.
Now the spacecraft has been steered again to safer, higher orbits. And naturally, this was all done in the name of science. It not only showed scientists information about the atmosphere, but also gave them engineering data of how a spacecraft behaves when it touches a planetary atmosphere at high speed. That could be useful for future landing missions.
“We have collected valuable data on the Venusian atmosphere in a region difficult to characterise by other means,” stated Hakan Svedhem, Venus Express project scientist for the European Space Agency.
“The results show that the atmosphere seems to be more variable than previously thought for this altitude range, but further analysis will be needed in order to explain these variations properly.”
The dips into hell were hard on the spacecraft. At times, its temperatures rose by more than 212 degrees Fahrenheit (100 degrees Celsius). That said, initial surveys of the spacecraft show all is well, although more analysis will be needed. Also, its orbit was reduced by more than an hour because its speed was slowed down by so much.
While the spacecraft performed 15 thruster burns to raise up above the atmosphere, the reprieve will be temporary. There is little fuel left in the spacecraft, which has been been at the planet since 2006. Now its new lowest point in the orbit is 460 km (286 miles), but over the next few months it will fall again due to the force of gravity. Mission planners expect the spacecraft will survive until about December, when it falls into the atmosphere for good.
“Aerobraking can be used to reduce the speed of a spacecraft approaching a planet or moon with an atmosphere, allowing it to be captured into orbit, and to move from an elliptical orbit to a more circular one,” the agency wrote.
“Less fuel has to be carried, yielding benefits all round. The technique will be used on future missions and the Venus Express experiments will help guide their design.”
Artist’s conception of Venus Express doing an aerobraking maneuver in the atmosphere in 2014. Credit: ESA–C. Carreau
The sunshield test unit on NASA's James Webb Space Telescope is unfurled for the first time. Credit: NASA
GODDARD SPACE FLIGHT CENTER, MD – The huge Sunshield test unit for NASA’s James Webb Space Telescope (JWST) has been successfully unfurled for the first time in a key milestone ahead of the launch scheduled for October 2018.
Engineers stacked and expanded the tennis-court sized Sunshield test unit last week inside the cleanroom at a Northrop Grumman facility in Redondo Beach, California.
NASA reports that the operation proceeded perfectly the first time during the test of the full-sized unit.
The Sunshield and every other JWST component must unfold perfectly and to precise tolerances in space because it has not been designed for servicing or repairs by astronaut crews voyaging beyond low-Earth orbit into deep space, William Ochs, Associate Director for JWST at NASA Goddard told me in an exclusive interview.
Artist’s concept of the James Webb Space Telescope (JWST) with Sunshield at bottom. Credit: NASA/ESA
The five layered Sunshield is the largest component of the observatory and acts like a parasol.
Its purpose is to protect Webb from the suns heat and passively cool the telescope and its quartet of sensitive science instruments via permanent shade to approximately 45 kelvins, -380 degrees F, -233 C.
The kite-shaped Sunshield provides an effective sun protection factor or SPF of 1,000,000. By comparison suntan lotion for humans has an SPF of 8 to 40.
Two sides of the James Webb Space Telescope (JWST). Credit: NASA
The extreme cold is required for the telescope to function in the infrared (IR) wavelengths and enable it to look back in time further than ever before to detect distant objects.
The shield separates the observatory into a warm sun-facing side and a cold anti-sun side.
Its five thin membrane layers also provides a stable thermal environment to keep the telescopes 18 primary mirror segments properly aligned for Webb’s science investigations.
JWST is the successor to the 24 year old Hubble Space Telescope and will become the most powerful telescope ever sent to space.
The Webb Telescope is a joint international collaborative project between NASA, the European Space Agency (ESA) and the Canadian Space Agency (CSA).
NASA has overall responsibility and Northrop Grumman is the prime contractor for JWST.
Webb will launch folded up inside the payload fairing of an ESA Ariane V ECA rocket from the Guiana Space Center in Kourou, French Guiana.
In launch configuration, the Sunshield will surround the main mirrors and instruments like an umbrella.
During the post launch journey to the L2 observing orbit at the second Sun-Earth Lagrange point nearly a million miles (1.5 million Km) from Earth, the telescopes mirrors and sunshield will begin a rather complex six month long unfolding and calibration process.
The science instruments have been mounted inside the ISIM science module and are currently undergoing critical vacuum chamber testing at NASA Goddard Space Flight Center which provides overall management and systems engineering.
Gold coated flight spare of a JWST primary mirror segment made of beryllium and used for test operations inside the NASA Goddard clean room. Credit: Ken Kremer- kenkremer.com
The mirror segments have arrived at NASA Goddard where I’ve had the opportunity to observe and report on work in progress.
Stay tuned here for Ken’s continuing JWST, MMS, ISS, Curiosity, Opportunity, SpaceX, Orbital Sciences, Boeing, Orion, MAVEN, MOM, Mars and more Earth and Planetary science and human spaceflight news.
The road to a comet isn't an easy one! Luckily Rosetta and Philae have a lot of help.
…and that time is now! ESA’s Rosetta spacecraft is just over a mere two weeks away from its arrival at Comet 67P/Churyumov-Gerasimenko (which has recently surprised everyone with its binary “rubber duckie” shape) and the excitement continues to grow — and rightfully so, since after ten years traveling through the Solar System Rosetta is finally going to achieve its goal of being the first spacecraft to orbit a comet!
As part of the “Are We There Yet” campaign to encourage public participation in this historic space exploration event, ESA has released the next installment of Rosetta’s story in adorable animated format. Check it out above, and feel free to fall in love with a solar-powered spacecraft.
Keep up with Rosetta’s journey on the ESA website here, and enter the #RosettaAreWeThereYet contest by sharing your photos here (you could win a trip to ESA’s Operations Center in Darmstadt, Germany in November for Philae’s landing party!)
Artist's conception of the final Automated Transfer Vehicle (ATV), Georges Lemaître, breaking up during re-entry following a cargo run to the International Space Station. Credit: ESA–D. Ducros
It’s sad to think about, but there will be a day sometime when the International Space Station makes its final journey — a destructive re-entry into Earth’s atmosphere. Historically, it’s been hard to break up large pieces of space hardware safely. Pieces of the Skylab space station famously rained down in Australia, while Mir’s demise triggered warnings across its re-entry path.
The European Space Agency sees an opportunity to gather more information for this future use: closely watching what happens when the final Automated Transfer Vehicle (ATV), Georges Lemaître, goes to the International Space Station and has its planned breakup in the atmosphere following the shipment.
They plan to record its last moments using a heat-seeking camera on the inside of the spacecraft. This sort of thing has been done before with NASA and the Japanese Aerospace Exploration Agency, but this will be a first for ESA.
“The data should also hold broader value,” stated Neil Murray, who is leading the project at the European Space Agency (ESA).
“The project is proceeding under our ‘Design for Demise’ effort to design space hardware in such a way that it is less likely to survive reentry and potentially endanger the public. Design for Demise in turn is part of the agency’s clean space initiative, seeking to render the space industry more environmentally friendly in space as well as on Earth.”
The Automated Transfer Vehicle Albert Einstein burning up on Nov. 2, 2013 at 12:04 GMT over an uninhabitated part of the Pacific Ocean. This picture was snapped from the International Space Station. Credit: ESA/NASA
The camera will ride inside, bolted to a rack, and transmit the last 20 seconds of its lifetime to a special Reentry Satcom capsule that is designed to survive the breakup. The data will in turn be sent to Earth using an Iridium satellite.
While the SatCom will be protected by a heatshield, the challenge will be transmitting the information through the plasma generated as it falls at 6 to 7 kilometers (3.7 to 4.3 miles) a second. The breakup will happen at 80 kilometers (50 miles) and the plasma will be there until below an altitude of about 40 kilometers (25 miles), ESA stated.
“The fall will generate high-temperature plasma around it, but signals from its omnidirectional antenna should be able to make it through any gap in the plasma to the rear,” the agency added.
Georges Lemaître is expected to launch later this month and last six months in space before re-entry.
The Rosetta spacecraft captured these pictures of its destination, Comet 67P/Churyumov-Gerasimenko, from 23,000 miles (37,000 kilometers) away on July 4, 2014. Credit: ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DASP/IDA
Up for a little abstract art, anyone? The latest images of the nucleus of Rosetta’s comet makes it look like the celestial object is a kidney. Or perhaps a bean. But regardless of what you “see” in the shape, scientists agree that the comet’s heart certainly isn’t round.
It’s a tantalizing view as the spacecraft speeds towards Comet 67P/Churyumov-Gerasimenko for an August rendezvous. These pictures were taken just a few days ago from 23,000 miles (37,000 kilometers) away, and the spacecraft is drawing noticeably nearer every week. What will a closer view reveal?
“Irregular, elongated, and structured shapes are not uncommon for small bodies such as asteroids and comets,” stated the Max Planck Institute for Solar System Research in a release. “Of the five cometary nuclei that have been visited by spacecraft in close flybys so far, all are far from spherical.”
To illustrate, we’ve put some examples below of the other comets that have had close-up views:
Jets can be seen streaming out of the nucleus, or main body, of comet Hartley 2 in this image from NASA’s EPOXI mission. The nucleus is approximately 2 kilometers (1.2 miles) long and .4 kilometers (.25 miles) across at the narrow “neck.” Credit: NASA/JPL-Caltech/UMDHalley’s Comet, as seen by the European Giotto probe. Credit: Halley Multicolor Camera Team, Giotto Project, ESANASA’s Stardust-NExT mission took this image of comet Tempel 1 at 8:39 p.m. PST (11:39 p.m. EST) on Feb 14, 2011. The comet was first visited by NASA’s Deep Impact mission in 2005. Credit: NASA/JPL-Caltech/Cornell. Image brightened and enhanced to show additional detail.Comet Borrelly’s 5-mile (8-kilometer) long nucleus taken from more than 2,000 miles (3,400 kilometers) away. Picture from NASA’s Deep Space 1 probe. Credit: NASA/JPLThe nucleus of Comet 81P/Wild taken by NASA’s Stardust probe in 2004. Credit: NASA
The new pictures from Rosetta come shortly after the spacecraft caught its comet tumbling through space. It’s not really known for sure what the nucleus will look like, although several artists have lent their ideas over the years. Luckily, the European Space Agency probe will give us a very close-up view of the comet, as it plans to deploy a lander called Philae to land on the comet’s surface in November.
Both Rosetta and Philae successfully awoke from hibernation earlier this year and all systems appear to be working well so far as they get ready for the close-up encounter with the comet. The spacecraft have been flying through space for about a decade, and will remain with Comet 67P/Churyumov-Gerasimenko as it sweeps to its closest approach to the sun in 2015, between the orbits of Earth and Mars.
The "Dropter" project aims to have a mothership that carries a rover safely to the surface before flying away. Credit: Airbus Defence & Space
How do you land a machine on the Red Planet? Appears that the answer keeps changing as engineers get smarter about solving the problem.
Over the years, NASA has experimented with approaches ranging from soft landings to inflatable airbags to the famous “Sky Crane” that landed Curiosity on Mars in 2012. And in this video above, you can see the European Space Agency taking the sky crane idea a little further in prototype testing.
“Starting from scratch for the eight-month project, the Dropter team was challenged to produce vision-based navigation and hazard detection and avoidance for the dropship,” the European Space Agency stated. “It has to identify a safe landing site and height before winching down its passenger rover on a set of cables.”
As you can see in the video, the dropship flew as high as 56 feet (17 meters), began lowering the rover around 33 feet (10 meters), and then lowered the rover until the little machine touched the ground.
“Saw a beautiful Southern Light last night. I so wish you could see this with your own eyes!” Image taken from the International Space Station (ISS) on 5 July 2014. Credit: ESA/Alexander Gerst
Spectacular snapshots of the Southern Lights, Shooting Stars, the Sahara Desert and much more are streaming back from space to Earth courtesy of Alexander Gerst, ESA’s German astronaut currently serving aboard the International Space Station (ISS).
See a gallery of Alex’s stunning space-based views (sagenhafte Weltraum bilder) collected herein – starting with the auroral fireworks seen from space – above. It coincides with the Earth-based fireworks of America’s 4th of July Independence Day weekend celebrations and spectacular Noctilucent Clouds (NLCs) wafting over the Northern Hemisphere. NLC gallery here.
“Saw a beautiful Southern Light last night. I so wish you could see this with your own eyes!” Alex tweeted in English.
Gerst is posting his Earth & space imagery from the ISS on a variety of social media including Twitter, Facebook, Google+ and his ESA astronaut blog bilingually in English and German.
Another new snapshot of Earth’s “beautiful Southern Lights” taken from the ISS on 5 July 2014. Credit: ESA/Alexander Gerst
“Habe gestern ein wunderschönes Südlicht gesehen. Ich wünschte ihr könntet das mit eigenen Augen sehen!” Alex tweeted in German.
Check out Alexander Gerst’s stunning 1st timelapse video from the ISS:
Video Caption: ESA astronaut Alexander Gerst’s first timelapse from the International Space Station features the first shooting star that he saw from above. Made by stitching together over 250 images this short clip shows the beauty of our world and the space around it. Published on July 5, 2014. Credit: ESA/Alexander Gerst
Gerst launched to the ISS on his rookie space flight on May 28, 2014 aboard a Russian Soyuz capsule along with Russian cosmonaut Maxim Suraev and NASA astronaut Reid Wiseman.
ISS Expedition 40 patch
The trio are members of Expeditions 40 and 41 and joined three more station flyers already aboard – cosmonauts Alexander Skvortsov & Oleg Artemyev and astronaut Steve Swanson – to bring the station crew complement to six.
Alex will spend six months on the ISS for ESA’s Blue Dot mission. He is Germany’s third astronaut to visit the ISS. He is trained as a geophysicist and a volcanologist.
Gerst also has practiced and honed another talent – space barber! He shaved the heads of his two American crew mates – to match his bald head – after winning a friendly wager with them when Germany beat the US in a 2014 FIFA World Cup match on June 26.
Here’s several of Alexander Gerst’s newest views of the Sahara Desert and more.
“Even from space, the Sahara looks dry! Sogar vom Weltraum aus, sieht die Sahara trocken aus!” Taken from the ISS on 6 July 2014. Credit: ESA/Alexander Gerst“Harsh land. Windswept valleys in northern Africa. Hartes Land. Windgefraeste Taeler in Nordafrika.” Taken from the ISS on 6 July 2014. Credit: ESA/Alexander Gerst“Sometimes our atmosphere looks incredibly complex and three-dimensional, sometimes you don’t even see it. Manchmal schaut unsere Atmosphäre unglaublich Komplex und dreidimensional aus, manchmal fast unsichtbar.” Taken from the ISS on 5 July 2014. Credit: ESA/Alexander GerstAntarctic aurora. The Antarctic aurora, photographed by ESA astronaut Alexander Gerst and posted on social media with the comment: “Antarctic Aurora fleeing from sunrise. I have rarely seen something more magical in my life!” Credits: ESA/NASA/Alexander Gerst
Stay tuned here for Ken’s continuing ISS, OCO-2, GPM, Curiosity, Opportunity, Orion, SpaceX, Boeing, Orbital Sciences, MAVEN, MOM, Mars and more Earth & Planetary science and human spaceflight news.
Learn more about Orbital Sciences Antares ISS launch on July 11 from NASA Wallops, VA, and more about SpaceX, Boeing, commercial space, NASA’s Mars missions and more at Ken’s upcoming presentations.
July 10/11: “Antares/Cygnus ISS Launch from Virginia” & “Space mission updates”; Rodeway Inn, Chincoteague, VA, evening
Animation of Comet 67P/Churyumov-Gerasimenko as seen by Rosetta on June 27-28, 2014
This is really getting exciting! ESA’s Rosetta spacecraft (and the piggybacked Philae lander) are in the home stretch to arrive at Comet 67P/Churyumov-Gerasimenko in 34 days and the comet is showing up quite nicely in Rosetta’s narrow-angle camera. The animation above, assembled from 36 NAC images acquired last week, shows 67P/C-G rotating over a total elapsed time of 12.4 hours. No longer just an extra-bright pixel, it looks like a thing now!
The animation, although fascinating, only hints at the “true” shape of the comet’s nucleus. Reflected light does create a bloom effect in the imaging sensor, especially at such small resolutions, expanding the apparent size of the comet beyond its 4-by-4-pixel size. But rest assured that much, much better images are on the way as Rosetta gets closer and closer.
The spacecraft was about 86,000 km (53,440 miles) from 67P/C-G when the images were acquired. Since that time it has cut that distance in half, and by this weekend it will be less than 36,000 km (22,370 miles) from the comet. After more than a decade of traveling around the inner Solar System Rosetta is finally arriving at its goal! Click here to see where Rosetta is now.
Stay tuned for more exciting updates from Rosetta, and learn more about the mission below:
Diagram of Comet 67P/C-G compared to terrestrial landmarks (ESA)
Pretty darn big, I’d say.
The illustration above shows the relative scale of the comet that ESA’s Rosetta and Philae spacecraft will explore “up-close and personal” later this year. And while it’s one thing to say that the nucleus of Comet 67P/Churyumov-Gerasimenko is about three by five kilometers in diameter, it’s quite another to see it in context with more familiar objects. Think about it — a comet as tall as Mt Fuji!
Artist’s impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.
At the time of this writing Rosetta is 35 days out on approach to Comet 67P/C-G, at a distance of about 51,000 km (31,700 miles) and closing. Three “big burn” maneuvers have already been performed between May 7 and June 4 to adjust the spacecraft’s course toward the incoming comet, and after smaller ones on June 18 and July 2 there are a total of five more to go. See details of Rosetta’s burn maneuvers here.
Luckily the remaining burns are relatively small compared to the first three, with the final being very brief, so any data contamination by Rosetta’s own exhaust shouldn’t become an issue once the spacecraft has established orbit in August.
Launched in March 2004, ESA’s Rosetta mission will be the first to orbit and land a probe on a comet, observing its composition and behavior as it makes its close approach to the Sun in 2015. Click here to see where Rosetta is right now.
Note: While 3-5 km seems pretty big (especially when stood on end) comet nuclei can be much larger, 10 to 20 km in diameter up to the enormous 40+ km size of Hale-Bopp. As comets go, 67P/C-G is fairly average. (Except that, come August, it will be the only comet with an Earthly spacecraft in tow!)
