Posted on by Jason Major

ESA Turns On The JUICE For New Jupiter Mission

Galileo image of Ganymede, Jupiter's - and the Solar System's - largest moon. (Ted Stryk)

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The European Space Agency has given the go-ahead for an exciting mission to explore the icy moons of Jupiter, as well as the giant planet itself.

JUICE — JUpiter ICy moons Explorer — will consist of a solar-powered spacecraft that will spend 3.5 years within the Jovian system, investigating Ganymede, Europa and the upper atmosphere of Jupiter. Anticipated to launch in June 2022, JUICE would arrive at Jupiter in early 2030.

As its name implies, JUICE’s main targets are Jupiter’s largest icy moons — Ganymede and Europa — which are thought to have liquid oceans concealed beneath their frozen surfaces.

The largest moon in the Solar System, Ganymede is also thought to have a molten iron core generating a magnetic field much like Earth’s. The internal heat from this core may help keep Ganymede’s underground ocean liquid, but the dynamics of how it all works are not quite understood.

JUICE will also study the ice-coated Europa, whose cueball-smooth surface lined with cracks and jumbled mounds of frozen material seem to be sure indicators of a subsurface ocean, although how deep and how extensive is might be are still unknown — not to mention its composition and whether or not it could be hospitable to life.

The rust-colored cracks lining Europa's otherwise smooth surface hint at a subsurface ocean. (Ted Stryk)

“JUICE will give us better insight into how gas giants and their orbiting worlds form, and their potential for hosting life,” said Professor Alvaro Giménez Cañete, ESA’s Director of Science and Robotic Exploration.

The JUICE spacecraft was originally supposed to join a NASA mission dedicated to the investigation of Europa, but NASA deemed their proposed mission too costly and it was cancelled. According to Robert Pappalardo, study scientist for the Europa mission based at JPL, NASA may still supply some instruments for the spacecraft “assuming that the funding situation in the United States can bear it.”

Artist's rendering of JUICE at Jupiter. (ESA/AOES)

JUICE will also capture images of Jupiter’s moon Callisto and search for aurorae in the gas giant’s upper atmosphere, as well as measure the planet’s powerful magnetic field. Once arriving in 2030, it will spend at least three years exploring the Jovian worlds.

Read more in today’s news release from Nature, and stay tuned to ESA’s JUICE mission page here.

Recalibrated Galileo images © Ted Stryk. See more of Ted’s excellent work on his site Planetary Images From Then And Now.

Posted on by Nancy Atkinson

ESA’s Ailing Envisat Imaged by Another Earth Orbiting Satellite

France's Pleiades Earth observation satellite captured this image of the silent Envisat satellite on April 15, 2012, from a distance of about 100 km. Credit: CNES

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ESA’s mysteriously silent Envisat Earth observing satellite has been observed and imaged by another satellite in space. France’s space agency (CNES) pulled off an on-orbit coup, using their high-resolution Pleiades satellite to take a picture of Envisat from about 100 km. The good news is that engineers were able to determine Envisat is fully intact and has not been obviously damaged by impacts by space debris or meteoroids. The massive Envisat fell silent on April 8 after 10 years of service – twice its designed lifetime — providing high quality images and data of our changing Earth.

“We are really grateful to CNES for offering to acquire images of Envisat using their Pleiades and Spot satellites,” said Volker Liebig, ESA’s Director of Earth Observation Programs. “Additional observations being acquired across the globe show how the international space community has come together to track this veteran satellite.”

Previous optical, radar and laser observations of Envisat show it is still in a stable orbit. However, engineers have not even been able to determine if the satellite is in ‘safe mode’ or if it has just gone dead. They say knowing this would be a starting point for revival and the recovery team is drawing on every information source available. If it is in safe mode, it may be possible to re-establish communications.

CNES was able to rotate the Pleiades satellite to capture images of Envisat. These images are being used to determine the orientation of Envisat’s solar panel – the satellite’s power source – to see if it is in a good position to generate power.

Envisat has been helping researchers examine our planet, completing more than 50,000 orbits and returned thousands of images, as well as a wealth of data about the land, oceans and atmosphere.

Source: ESA

Posted on by Jason Major

African Lake Has a Twin on Titan

Titan's Ontario Lacus is found to bear a striking resemblance to Namibia's Etosha Pan. (NASA/JPL/ESA)

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A large lake on Saturn’s cloud-covered Titan seems very similar to the Etosha Pan, a salt-encrusted dry lakebed in northern Namibia that periodically fills with water. As it turns out, Titan’s “great lake” may also be temporary.

Ontario Lacus, so named because of its similarity both in shape and size to Lake Ontario here on Earth, was first discovered near the south pole of Titan by the Cassini spacecraft in 2009. Its smooth, dark appearance in radar images indicated a uniform and reflective surface, implying a large — although likely shallow — body of liquid.

Of course, on Titan the liquid isn’t water — it’s methane, which is the main ingredient of the hydrologic cycle found on the giant moon. That far from the Sun the temperatures at Titan’s poles fall to a frigid -300ºF (-185ºC), much too cold for water to exist as a liquid and so, on this world, methane has taken its place.

A research team led by Thomas Cornet of the Université de Nantes, France has taken a closer look at Cassini’s radar data of Ontario Lacus and found evidence of channels carved into the southern portion. According to the team, this likely indicates that the lakebed surface is exposed.

Cassini image of Ontario Lacus. (NASA/JPL/SSI)

“We conclude that the solid floor of Ontario Lacus is most probably exposed in those areas,” said Cornet.

In addition, sediment layers surrounding the lake suggest that the liquid level has varied.

All in all, this reveals a striking resemblance between Ontario Lacus and Namibia’s Etosha Pan — an “ephemeral lake” that is dry for much of the year, occasionally filling with a shallow layer of water which evaporates, leaving salty rings of sediment.

The inherent otherworldly nature of Etosha Pan is further underlined — and perhaps foreshadowed! — by its use as a backdrop in the 1968 sci-fi film 2001: A Space Odyssey.

Although Ontario Lacus was initially thought to be permanently filled with liquid hydrocarbons, the team’s findings draw a strong correlation with this well-known Earthly environment, suggesting a much more temporary nature and showing the value of comparative research.

Satellite image of Etosha Pan, acquired on April 28, 2012. (Chelys/EOSnap)

“These results emphasise the importance of comparative planetology in modern planetary sciences,” said Nicolas Altobelli, Cassini project scientist for ESA.”Finding familiar geological features on alien worlds like Titan allows us to test the theories explaining their formation.”

Read the press release from ESA here.

Image credits: Cassini radar image JPL/NASA. Envisat radar image ESA. Composite image: LPGNantes.

Posted on by Nancy Atkinson

JUICE to Jupiter Could Be ESA’s Next Major Science Mission

Artist concept of JUICE, a Jupiter moons orbiter mission. Credit: ESA

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The Science Programme Committee of the European Space Agency has recommended that the next major space mission for ESA be an orbiter mission to the Jupiter system named JUICE, the JUpiter ICy moons Explorer. This mission would launch in about 2020 and explore potentially habitable moon around the gas giant, Callisto, Europa, and Ganymede.

This recommendation is not the final decision, but puts JUICE as a front-runner for when representatives of all 19 ESA member states meet to discuss the various mission candidates on May 2, 2012

Other missions being considered are ATHENA , the Advanced Telescope for High-ENergy Astrophysics (originally called IXO) – which would be the biggest X-ray telescope ever built — even though smaller in scope than the original IXO) and study the extremes of the Universe: from black holes to large-scale structure ; and NGO, the New Gravitational wave Observatory, a smaller version of LISA, a space-borne gravitational wave detector which would place a three satellites in orbit.

“This is a big blow to space based astrophysics,” wrote European science blogger Steinn Sigurdsson, who added that rumors are floating around that the NGO science team may be disbanded immediately, even though the new report issued by the Science Programme Committee is just a recommendation.

Planetary Society blogger Emily Lakdawalla also commented on the selection — if it is accepted — “represents a big win for planetary science and a big loss for space-based astrophysics in Europe. Which is, one can’t help but notice, opposite to what the currently-proposed NASA budget represents.”

Whatever mission is chosen for the next flagship science mission, ESA knows it will likely have to do it on their own.

In March 2011, NASA informed ESA that that it was highly unlikely that they could become a major partner in an “L” (large) mission for the 2020 timeframe.

“Given the resulting impossibility to continue with the mission concepts defined in the Assessment Phase, the Executive terminated the relative activities for EJSM-Laplace, IXO, and LISA, and informed the members of the three Science Study Teams of the termination of their mandate,” the new report says. “To preserve as much as possible the investment of the scientific community and of the Member States in the study activities of the L mission candidates, the Executive implemented a recovery action in the form of a fast-track re-formulation activity. The aim has been to ascertain if and which of the science goals of the L mission candidates could be implemented in the context of a programmatically feasible European-led, or potentially European-only mission.”

With NASA no longer in the mix, ESA knew they would have to descope their proposed missions, and with costs needing to be at least 20% less than originally planned. “Needless to say, missions within these constraints must be significantly less complex than the original L mission concepts selected in 2007,” the report says.

ESA’s science goals for the front-runner JUICE mission is to visit the Jupiter system concentrating on the characterization of three possible ocean-bearing worlds, Ganymede, Europa and Callisto as planetary objects and potential habitats and on the exploration of the Jupiter system considered as an archetype for gas giants in the solar system and elsewhere. The focus of JUICE is to characterize the conditions that may have led to the emergence of habitable environments among the Jupiter’s icy satellites.

Sources: Dynamics of Cats, Planetary Society blog,

Posted on by Jason Major

Is This The Last Image From Envisat?

This MERIS image of Spain and Portugal could be Envisat's last. (Chelys/EOsnap)

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The European Space Agency’s venerable Envisat satellite may have sent back its final image, according to recent news from the Agency.

On April 8, ESA lost communication with the Earth-observation satellite, preventing reception of data as it passed over the Kiruna station in Sweden. Although it’s been confirmed that the satellite is still in orbit, the recovery team has not been able to re-establish contact.

The image above, showing part of the Iberian peninsula, was from the last data to be received from Envisat before it fell silent.

Radar image of Envisat. (Fraunhofer Institute for High Frequency Physics and Radar Techniques.)

Launched in March 2002, Envisat has been helping researchers examine our planet for over ten years — five years longer than its original mission duration. It has completed more than 50,000 orbits and returned thousands of images, as well as a wealth of data about the land, oceans and atmosphere.

Envisat data was instrumental in over 4,000 projects from 70 countries.

Germany’s Tracking and Imaging Radar captured an image of the satellite, revealing that it is still intact and in a stable orbit. Still, all attempts at recovery have so far been unsuccessful.

A contingency agreement with the Canadian Space Agency on Radarsat will be activated to fulfill user requirements if Envisat cannot be brought back online.

Read the official release on the ESA site here.

Posted on by Jason Major

A Galaxy’s Bulge Divulges Its Spin

Hubble image of a deformed spiral galaxy in Hydra

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Although somewhat blobby and deformed, this is in fact a spiral galaxy, located in the southern constellation Hydra. Imaged by Hubble as part of a survey of galactic bulges, NGC 4980 exhibits what’s called a “pseudobulge” — an inline central concentration of stars whose similar spiral motion extends right down into its core.

As opposed to classical bulges, in which stars orbit their galaxy’s core in all directions, pseudobulges are made up of stars that continue along the spiral motion of the galactic arms all the way into the center. Pseudobulges are typically seen to contain stars that are the same age as most of the others in the galaxy.

In contrast, classical bulges usually contain stars older than those found in the disk, leading astrophysicists to believe that galaxies with classical bulges had undergone one or more collisions with other galaxies during their evolution.

Our own Milky Way is thought to have a pseudobulge, while some spiral galaxies have no discernible bulge at all.

This image is composed of exposures taken in visible and infrared light by Hubble’s Advanced Camera for Surveys. The image is approximately 3.3 by 1.5 arcminutes in size. NGC 4980 is located about 80 million light-years from Earth.

Read more on ESA’s Hubble site and find out more about galactic bulges on astrobites.com.

Image credit: ESA/Hubble and NASA. 

 

Posted on by Nancy Atkinson

Will Russia Rescue ExoMars?

The ExoMars program. Credit: ESA

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After NASA was forced to back out the joint ExoMars mission with the European Space Agency due to budget constraints, ESA went looking for help with the planned multi-vehicle Mars mission. Now, reportedly the Head of Roscosmos Vladimir Popovkin met with Director General of the ESA, Jean-Jacques Dordain last week, and the two signed a memorandum of understanding to work together to make ExoMars a reality.

“The sides consider this project feasible and promising,” Popovkin’s spokeswoman Anna Vedishcheva was quoted in Ria Novosti. “The sides are to sign the deal by year-end.”

Russia’s participation in the project was also approved by the space council of the Russian Academy of Sciences.

The ExoMars program was slated to send an orbiter to Mars in 2016 and a rover in 2018, but after NASA pulled out of its part of the bargain — of providing several science instruments and an Atlas launch vehicle – ESA knew they could not do the entire mission on their own. Last fall, when it was becoming apparent that NASA’s ability to participate was in jeopardy, Dordain extended an invitation to Russia, and in turn Roscosmos officials hinted they might be interested in joining, offering to provide the use of their Proton rockets for the launches. The two space agencies then had preliminary talks at the Ariane 5 launch at Kourou, French Guiana in March, 2012.

Russian space agency chief Vladimir Popovkin said that Russia’s financing of ExoMars could be partially covered by insurance payments of 1.2 billion rubles (about $40.7 million) for the lost Phobos-Grunt sample return mission that would have gone to the Martian moon Phobos.

Artist concept of the ExoMars/Trace Gas Orbiter mission. Credit: NASA

The details of the new ExoMars partnership are yet to be worked out, but the ESA/NASA partnership would have sent the Trace Gas Orbiter to the Red Planet in 2016 to search for atmospheric methane — a potential signature for microbial life – as well as an advanced astrobiology rover to drill into the surface in 2018, with the hopes of determining if life ever evolved on Mars.

Unsurprisingly, the potential deal with Russia comes as a huge relief to European space scientists who have spent years working on ExoMars. Journalist Paul Sutherland quoted UK scientist John Zarnecki of the Open University, as saying, “It looks like the cavalry has come riding over the horizon to save us, but this time they are dressed in Russian uniforms. There will be a lot scientists in universities and research institutes throughout Europe who will be very relieved to hear this news. Otherwise it seemed that several years work preparing instruments for this mission was going to go down the drain.”

Sources: Sen.com, Ria Novosti

Posted on by Jason Major

Could There Be Life In Them Thar Pits?

Computer-generated perspective of the Tractus Catene pit chains. Credit: ESA/DLR/FU Berlin (G. Neukum)

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Recent images from ESA’s Mars Express spacecraft reveal long rows of crater-like depressions lining the flanks of ancient Martian volcanoes located in the planet’s vast Tharsis region. Rather than being the result of impact events, these “pit chains” were likely caused by underground lava flows — and could be a prime location for look for life.

Like similar features found on Earth, lava tubes on Mars are the result of rivers of magma that carved channels beneath the surface. When these channels empty out, a hollow tube is left. If the roof of a particularly large tube is near the surface the roof can eventually collapse, creating a surface depression… or, in some cases, opening up to the surface entirely.

Even though volcanism on Mars isn’t currently active — the last eruptions probably took place at least over a million years ago — the features left by volcanic activity are still very much present today and likely well-preserved beneath the Martian surface.

Shielded from harsh solar and cosmic radiation, the interior of such lava tubes could provide a safe haven for microbial life — especially if groundwater had found its way inside at some point.

Even though the surface of Mars can receive 250 times the radiation levels found on Earth, the layers of soil and rock surrounding the tubes can provide adequate protection for life, whether it be ancient Martian microbes or future explorers from Earth.

A wider image of the Tractus Catena region showing the large shield volcano Ascraeus Mons. Credits: ESA/DLR/FU Berlin (G. Neukum)

Of course, water and protection from radiation aren’t the only factors necessary for life. There also needs to be some source of heat. Fortunately, the pit chains imaged by Mars Express happen to be within one of the most volcano-laden areas of the Red Planet, a region called the Arcadia quadrangle. Within this area exist some of the largest volcanoes on Mars — and the Tractus Catena pits are located right in the middle of them.

If a heat source were ever to have been beneath the surface of Mars, there would be a good chance it would have been here.

And if our own planet is any measure of such things, where there’s heat and water there is often some form of life — however extreme the conditions may be.

“I’d like to see us land ON a volcano,” Dr. Tracy Gregg, a volcanologist with the University of Buffalo, had once told Universe Today back in 2004. “Right on the flanks. Often the best place to look for evidence of life on any planet is near volcanoes.”

“That may sound counterintuitive, but think about Yellowstone National Park , which really is nothing but a huge volcano,” Gregg elaborated. “Even when the weather in Wyoming is 20 below zero, all the geysers, which are fed by volcanic heat, are swarming with bacteria and all kinds of happy little things cruising around in the water. So, since we think that the necessary ingredients for life on Earth were water and heat, we are looking for the same things on Mars.”

As far as any remaining geothermal activity still happening beneath the Martian surface?

“I strongly suspect there are still molten (or at least mushy) magma bodies beneath the huge Tharsis volcanoes,” Gregg had said. (Read the full article here.)

On Earth, lava tubes, caves and underground spaces of all kinds harbor life, often specialized forms that are found no place else. Could this be (or have once been) the case on Mars as well? Only future exploration will tell. Until then, places like Tractus Catena will remain on scientists’ short list of places to look.

Read more on the ESA website here.

Posted on by Jason Major

Hubble Gets Best Look Yet At Messier 9

New Hubble image of Messier 9 cluster resolves individual stars (NASA/ESA)

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First discovered by Charles Messier in 1764, the globular cluster Messier 9 is a vast swarm of ancient stars located 25,000 light-years away, close to the center of the galaxy. Too distant to be seen with the naked eye, the cluster’s innermost stars have never been individually resolved… until now.

This image from the Hubble Space Telescope is the most detailed view yet into Messier 9, capturing details of over 250,000 stars within it. Stars’ shape, size and color can be determined — giving astronomers more clues as to what the cluster’s stars are made of. (Download a large 10 mb JPEG file here.)

Hot blue stars as well as cooler red stars can be seen in Messier 9, along with more Sun-like yellow stars.

Unlike our Sun, however, Messier 9’s stars are nearly ten billion years old — twice the Sun’s age — and are made up of much less heavy elements.

Since heavy elements (such as carbon, oxygen and iron) are formed inside the cores of stars and dispersed into the galaxy when the stars eventually go supernova, stars that formed early on were birthed from clouds of material that weren’t yet rich in such elements.

Zoom into the Messier 9 cluster with a video from NASA and the European Space Agency below:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA. See more at www.spacetelescope.org.

Image credit: NASA & ESA. Video: NASA, ESA, Digitized Sky Survey 2, N. Risinger (skysurvey.org)

Posted on by Nancy Atkinson

20-Ton Cargo Freighter Arrives at Space Station

The heaviest cargo ship ever has arrived and docked to the International Space Station, laden with 7 tons of supplies for the 6-member ISS crew. The 20-ton European ATV-3 cargo ship, named “Edoardo Amaldi” after the Italian physicist and spaceflight pioneer, made a “smooth and gentle” docking on March 28, 2012, the European Space Agency said. The supplies delivered included food, drinking water, clothing, oxygen, spare parts and fuel.

The ATV launched from Kourou, French Guiana last Friday. It will use its engines to boost the space station during its 5-month stay on orbit. It is scheduled to undock on August 27 and perform an “orbital cremation” of trash from the space station.