Monday, March 31, 2014

ESA Rosetta Image: Comet 67P/Churymov-Gerasimenko in the constellation Ophiuchus

The OSIRIS Narrow Angle Camera aboard ESA's Rosetta probe captured this image on March 21, 2014, showing Comet 67P/Churyumov–Gerasimenko in the constellation Ophiuchus.

Credit: ESA

The ESA's Rosetta spacecraft opened its eyes in January after a 10-year voyage across the solar system and a long hibernation in deep space.

For the first time since its wakeup call, Rosetta spied its destination.

ESA released images Thursday (March 27) showing Rosetta's glimpse of its target, Comet 67P/Churyumov–Gerasimenko.

The "first light" images were captured on March 20 and 21 by the OSIRIS wide-angle camera and narrow-angle camera aboard Rosetta, from more than 3 million miles (5 million kilometers) away from the comet.

"Finally seeing our target after a 10 year journey through space is an incredible feeling," Holger Sierks, the OSIRIS principal investigator from the Max Planck Institute for Solar System Research in Germany, said in a statement.

Holger Sierks
"These first images taken from such a huge distance show us that OSIRIS is ready for the upcoming adventure."

The light from the faraway, 2.5-mile-wide (4 km) comet doesn't even fill up a single pixel.

To create the image, researchers had to obtain a series of 60–300 second exposures.

It took 37 minutes for each image to reach Earth and about an hour for each to download, ESA officials said.

ESA's Rosetta, a solar-powered probe, is on track to enter orbit around the icy body in August 2014. By then, Rosetta should have a 2-meter (6.5 feet) per pixel view of Comet 67P/Churyumov–Gerasimenko, complete with surface features.

A robotic lander called Philae, which is piggybacking on Rosetta, is scheduled to touch down on the comet in November 2014.

Securing itself with a harpoon and ice screws, Philae will drill samples and conduct experiments with its 10 science instruments, as Rosetta looks on from above.

If all goes as planned, Rosetta and Philae will continue their observations through December 2015.

ESA and CERN sign cooperation agreement

ESA, the European Space Agency, and CERN, the European Organisation for Nuclear Research, signed a cooperation agreement on 28 March to foster future collaborations on research themes of common interest.

This year, CERN is celebrating its 60th anniversary as ESA is celebrating 50 years of European space activities.

Mauro Dell'Ambrogio
Mauro Dell'Ambrogio, the State Secretary for Education, Research and Innovation of Switzerland, highlighted how the two institutions complement each other as examples of successful European collaboration and worldwide excellence in science and technology: "CERN and ESA are two examples that attest to the approach of European collaboration for global benefit."

Genevieve Fioraso
Genevieve Fioraso, Minister for Higher Education and Research of France, stated that, "This cooperation agreement brings concrete expression to the long shared history of two international organisations that are emblematic of the strength of European science: CERN and ESA.

"This joining together in the exploration of the infinite, from the infinitely large that is the focus of the sciences of the Universe to the infinitely small in high energy physics, opens up new avenues for science and technology, bringing progress and strengthening European industry."

"ESA and CERN are the daughters of visionaries like Edoardo Amaldi, testimony that, when we share the same challenging objectives and join forces, Europe is at the leading edge of progress, innovation and growth," said Jean-Jacques Dordain, ESA's Director General.

Russian Rocket launch fails at Kapustin Yar - Weather Satellite payload

A weather rocket launched from Russia's Kapustin Yar launching field crashed in Kazakhstan's western region, according to government reports.

The incident happened early in the morning on March 27, between 1 and 2 a.m., a government source said.

The rocket fell less than one kilometer away from a local village named Shungai with no casualties reported.

According to reports from Kapustin Yar, it was an accident caused by a propulsion system failure, which kept the rocket from reaching its designated destination.

Meanwhile, Kazakhstan's Defense Ministry said it will suspend all Russian missile experiments on leased testing fields in Kazakhstan until the cause of the crash is identified, according to the ministry's website.

"The Ministry of Defense of Kazakhstan has suspended Russia's testing on the leased military grounds in Kazakhstan until the cause of the accident is found," the press office of the Defense Ministry said on Friday.

Kazakhstan's Environmental Regulation and Control Department said soil and air samples will be collected from the crash site to assess the environmental impact.

Kapustin Yar is known to be a launch site for smaller space vehicles. It is also one of Russia's first missile test ranges. During Soviet time a number of intermediate and short range missile projects were tested there.

ESA's Compact Payload Test Range for antenna testing

ESA's Compact Payload Test Range for antenna testing

Metal walls screen outside radio signals while spiky foam interior cladding absorbs radio signals internally to create conditions simulating the infinite void of space. Image courtesy ESA-Anneke Le Floc'h.

Kept isolated from the external Universe, a special ESA chamber simulates the boundless emptiness of space for testing satellite antennas.

Recently refitted, it is in need of a new name. Come up with a winning suggestion and you can visit it for yourself.

Long sporting the workaday name of Compact Payload Test Range, this chamber at ESA's technical heart in the Netherlands is a crucial part of the Agency's ability to check antennas attached to complete five-tonne satellites.

Metal walls block out all external electromagnetic signals such as TV and radio, radar and even mobile phone calls and the chamber's interior walls are clad with spiky 'anechoic' foam cladding to absorb radio signals internally.

A lot of internal noise is similarly absorbed - making for a notably hushed workplace as engineers prepare items for testing, most recently ESA's latest Galileo satellites.

"The Range is more than 25 years old, but bearing in mind the needs of future ESA missions it was recently refitted," explains Luis Rolo, overseeing the facility.

"It has now become one of the few antenna test ranges in the world able to measure the performance of large antennas using near-field and far-field techniques inside the same anechoic chamber.

"Most equivalent sites focus on one measurement type or the other. So we are looking for a new name to reflect this new dual capability."

A pair of carefully shaped carbon fibre reflectors transforms the spherical expanding radio signals coming to or from the satellite into a straight signal beam as though from far away in space.

This feature means that 'far-field' measurements equivalent to long-range testing can be reliably carried out even in a chamber of limited size - which is where the 'compact' in the name comes from.

Then, last year, the Range gained a state-of-the-art 'near-field scanner' to measure the electromagnetic fields in the immediate vicinity of a test antenna or complete satellite. Either the scanner or the test item itself can be moved to build up a complete map of its 'near-field' radiation patterns.

"These near-field measurements can then be mathematically processed to model their equivalent far-field performance," adds Luis. "Both classes of testing can cover a broad range of frequencies, offering huge versatility to our internal and external customers."

Suggest a name

The competition to suggest a name is open to any citizen of ESA's Member States. Just email your suggestion plus a short explanation to, including 'COMPETITION' in the header.

The winning suggestion will receive a tour of ESTEC, including the Range, and a collector's copy of the large format photo-book, The ESA Effect.

NRL SSULI: Satellite to measure ionosphere electron density

Says Andrew Nicholas, Principal NRL Investigator, "What we're looking at is naturally occurring air glow emissions from the upper atmosphere." 

Shown is the daily averaged electron density over two years; as a function of altitude and day of the year in the post-sunset, equatorial ionosphere. 

F18 SSULI measured the nightside oxygen 135.6 nm radiative recombination emission intensity, capturing the ionosphere's variations daily and over the long-term as associated with seasons and solar cycles. 

Credit: U.S. Naval Research Laboratory

On April 3rd, 2014, a satellite carrying a U.S. Naval Research Laboratory (NRL) space weather instrument will launch from Vandenberg Air Force Base.

Special Sensor Ultraviolet Limb Imager (SSULI)
Called the Special Sensor Ultraviolet Limb Imager (SSULI), "SSULI makes accurate measurements of the upper atmosphere and ionosphere that are ultimately useful to the warfighter," says Dr. Scott Budzien, the NRL Program Manager.

"Down in the lower atmosphere, the characteristics of weather that are important are temperature, precipitation, wind, and so on," he says.

"But in the ionosphere, the aspects that are important for our systems are electron density, the morphology and gradients of electron density, and the height where the ionosphere lies."

SSULI measures the density of the ionosphere (as ions or electrons per cubic centimeter). Says Andrew Nicholas, the Principal Investigator, "We are measuring naturally occurring airglow emissions from the upper atmosphere."

The density profiles go into the Department of Defense's weather system, which the U.S. Air Force has run since the 1940s to collect observations about terrestrial and space weather.

"SSULI helps provide a very good specification of the state of the atmosphere, a nowcast," says Budzien.

With a more accurate nowcast, forecasting models better predict space weather into the future.

Space weather is important for military operations, because how signals are transmitted or reflected influences the reliability of radar and of communication and navigation systems.

Configuration of Operational Polar Satellites
The April 3rd Defense Meteorological Satellite Program (DMSP) mission, Flight-19 (F19), is the fourth to carry a SSULI from NRL.

The DMSP satellites are low-earth orbiting satellites, flying at about 830-840 kilometers (km) above the ground.

"They fly in a sun-synchronous orbit, which means they are always at the same local time," says Budzien.

"The one we are launching in April is going into a terminator orbit, right at the day-night boundary."

NRL built five SSULIs in the early 1990s; the last launch is currently planned for 2016. But, says Budzien, "Based on the lessons learned from SSULI, we've developed the design for a smaller, more sensitive instrument."

Still just a concept, Budzien hopes to identify a sponsor who will help "to continue to provide improved products for the warfighter."

NASA SDO images of X-class solar flare

Extreme ultraviolet light streams out of an X-class solar flare as seen in this image captured on March 29, 2014, by NASA's Solar Dynamics Observatory (SDO)

This image blends two wavelengths of light: 304 and 171 Angstroms, which help scientists observe the lower levels of the sun's atmosphere. 

Credit: NASA/SDO

The sun emitted a significant solar flare, peaking at 1:48 p.m. EDT March 29, 2014, and NASA's Solar Dynamics Observatory (SDO) captured images of the event.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however, when intense enough, they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event impacted Earth, please visit NOAA's Space Weather Prediction Center, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.

This flare is classified as an X.1-class flare. X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.

PPPL QUASAR Stellerator: A concept on the path to fusion energy

QUASAR stellerator design. Credit: PPPL

Completion of a promising experimental facility at the U.S. Department of Energy's Princeton Plasma Laboratory (PPPL) could advance the development of fusion as a clean and abundant source of energy for generating electricity, according to a PPPL paper published this month in the journal IEEE Transactions on Plasma Science.

The facility, called the Quasi-Axisymmetric Stellarator Research (QUASAR) experiment, represents the first of a new class of fusion reactors based on the innovative theory of quasi-axisymmetry, which makes it possible to design a magnetic bottle that combines the advantages of the stellarator with the more widely used tokamak design.

Experiments in QUASAR would test this theory.

Construction of QUASAR, originally known as the National Compact Stellarator Experiment (NCSE), was begun in 2004 and halted in 2008 when costs exceeded projections after some 80 percent of the machine's major components had been built or procured.

George "Hutch" Neilson
"This type of facility must have a place on the roadmap to fusion," said physicist George "Hutch" Neilson, the head of the Advanced Projects Department at PPPL.

Both stellarators and tokamaks use magnetic fields to control the hot, charged plasma gas that fuels fusion reactions.

While tokamaks put electric current into the plasma to complete the magnetic confinement and hold the gas together, stellarators don't require such a current to keep the plasma bottled up.

Stellarators rely instead on twisting, or 3D, magnetic fields to contain the plasma in a controlled "steady state."

Stellarator plasmas thus run little risk of disrupting or falling apart as can happen in tokamaks if the internal current abruptly shuts off.

ITER: the world's largest Tokamak
Developing systems to suppress or mitigate such disruptions is a challenge that builders of tokamaks like ITER, the international fusion experiment under construction in France, must face.

Stellarators had been the main line of fusion development in the 1950s and early 1960s before taking a back seat to tokamaks, whose symmetrical, doughnut-shaped magnetic field geometry produced good plasma confinement and proved easier to create.

But breakthroughs in computing and physics understanding have revitalized interest in the twisty, cruller-shaped stellarator design and made it the subject of major experiments in Japan and Germany.

PPPL developed the QUASAR facility with both stellarators and tokamaks in mind. Tokamaks produce magnetic fields and a plasma shape that are the same all the way around the axis of the machine—a feature known as "axisymmetry." QUASAR is symmetrical too, but in a different way.

While QUASAR was designed to produce a twisting and curving magnetic field, the strength of that field varies gently as in a tokamak, hence the name "quasi-symmetry" (QS) for the design.

This property of the field strength was to produce plasma confinement properties identical to those of tokamaks.

"If the predicted near-equivalence in the confinement physics can be validated experimentally," Neilson said, "then the development of the QS line may be able to continue as essentially a '3D tokamak.'"

More information: Neilson, G.H.; Gates, D.A.; Heitzenroeder, P.J.; Breslau, J.; Prager, S.C.; Stevenson, T.; Titus, P.; Williams, M.D.; Zarnstorff, M.C., "Next Steps in Quasi-Axisymmetric Stellarator Research," Plasma Science, IEEE Transactions on , vol.42, no.3, pp.489,494, March 2014. DOI: 10.1109/TPS.2014.2298870

NASA Gravity Probe B: Results of Epic Space-Time Experiment Announced

An artist's concept of GP-B measuring the curved spacetime around Earth.

Einstein was right again. There is a space-time vortex around Earth, and its shape precisely matches the predictions of Einstein's theory of gravity.

Researchers confirmed these points at a press conference today at NASA headquarters where they announced the long-awaited results of Gravity Probe B (GP-B).

"The space-time around Earth appears to be distorted just as general relativity predicts," says Stanford University physicist Francis Everitt, principal investigator of the Gravity Probe B mission.

"This is an epic result," adds Clifford Will of Washington University in St. Louis. An expert in Einstein's theories, Will chairs an independent panel of the National Research Council set up by NASA in 1998 to monitor and review the results of Gravity Probe B.

"One day," he predicts, "this will be written up in textbooks as one of the classic experiments in the history of physics."

Time and space, according to Einstein's theories of relativity, are woven together, forming a four-dimensional fabric called "space-time."

The mass of Earth dimples this fabric, much like a heavy person sitting in the middle of a trampoline. Gravity, says Einstein, is simply the motion of objects following the curvaceous lines of the dimple.

If Earth were stationary, that would be the end of the story. But Earth is not stationary. Our planet spins, and the spin should twist the dimple, slightly, pulling it around into a 4-dimensional swirl. This is what GP-B went to space in 2004 to check.

The idea behind the experiment is simple:

Put a spinning gyroscope into orbit around the Earth, with the spin axis pointed toward some distant star as a fixed reference point.

Free from external forces, the gyroscope's axis should continue pointing at the star--forever. But if space is twisted, the direction of the gyroscope's axis should drift over time.

By noting this change in direction relative to the star, the twists of space-time could be measured.

In practice, the experiment is tremendously difficult.

One of the super-spherical gyroscopes of Gravity Probe B.

The four gyroscopes in GP-B are the most perfect spheres ever made by humans.

These ping pong-sized balls of fused quartz and silicon are 1.5 inches across and never vary from a perfect sphere by more than 40 atomic layers.

If the gyroscopes weren't so spherical, their spin axes would wobble even without the effects of relativity.

According to calculations, the twisted space-time around Earth should cause the axes of the gyros to drift merely 0.041 arcseconds over a year. An arcsecond is 1/3600th of a degree.

To measure this angle reasonably well, GP-B needed a fantastic precision of 0.0005 arcseconds. It's like measuring the thickness of a sheet of paper held edge-on 100 miles away.

"GP-B researchers had to invent whole new technologies to make this possible," notes Will.

Nasa Space to Ground ISS Update Video

NASA's Space to Ground is your weekly update on what's happening aboard the International Space Station.

In this video the Soyuz launch and successful arrival of new ISS crew members and the ESA Minus Eighty-Degree Laboratory Freezer, (MELFI) used to freeze experiment samples.

The ESA Minus Eighty-Degree Laboratory Freezer (MELFI) is seen here in ESA, undergoing tests on the ground, prior to launch and installation in ISS

MELFI is not used for food storage, as you may imagine, because food storage and retrieval is a more complex and power hungry issue on the ISS, a space vessel with limited resources.

ISS Expedition 39 Crew: Safe Arrival at Space Station After 2-Day Delay

Expedition 39, now a six-member crew, talks to family and mission officials moments after entering the space station for the first time on March 27, 2014. 

Credit: NASA TV

Three new crew members have finally made it to the International Space Station, two days later than originally planned.

A Russian Soyuz spacecraft carrying NASA astronaut Steve Swanson and cosmonauts Alexander Skvortsov and Oleg Artemyev docked with the orbiting lab at 7:53 p.m. EDT (2353 GMT) Thursday (March 27), as the two spacecraft cruised over southern Brazil.

The hatch linking the two vehicles opened at 10:35 p.m. EDT Thursday, NASA officials said.

The three spaceflyers blasted off Tuesday afternoon EDT (March 25) and were slated to arrive at the station just six hours later, but the Soyuz failed to complete one of the automated burns required to pull off this "fast track" trip, forcing mission controllers to revert to a more traditional two-day chase and rendezvous.

All systems on the Soyuz now appear to be functioning normally, NASA officials said in an update Wednesday (March 26).

The arrival of SwansonSkvortsov and Artemyev brings the space station back up to its full complement of six crew members.

The newcomers join NASA's Rick Mastracchio, Japanese astronaut Koichi Wakata (ISS Commander) and cosmonaut Mikhail Tyurin, rounding out the current Expedition 39 aboard the orbiting lab.

Mastracchio, Expedition 39 commander Wakata and Tyurin had had the $100 billion station all to themselves since March 10, when another Soyuz capsule ferried the previous Russian-U.S. crew back down to Earth.

Shadow Portrait of NASA Rover Opportunity on Martian Slope

NASA's Mars Exploration Rover Opportunity caught its own silhouette in this late-afternoon image taken by the rover's rear hazard avoidance camera. 

This camera is mounted low on the rover and has a wide-angle lens.

The image was taken looking eastward shortly before sunset on the 3,609th Martian day, or sol, of Opportunity's work on Mars (March 20, 2014).

The rover's shadow falls across a slope called the McClure-Beverlin Escarpment on the western rim of Endeavour Crater, where Opportunity is investigating rock layers for evidence about ancient environments.

The scene includes a glimpse into the distance across the 14-mile-wide (22-kilometer-wide) crater.

Image Credit: NASA/JPL-Caltech

A Tertrad of Lunar Eclipses - Video

A total lunar eclipse on April 15th marks the beginning of a remarkable series of eclipses all visible from North America.

For people in the United States, an extraordinary series of lunar eclipses is about to begin. The action starts on April 15th when the full Moon passes through the amber shadow of Earth, producing a midnight eclipse visible across North America.

So begins a lunar eclipse tetrad-a series of 4 consecutive total eclipses occurring at approximately six month intervals.

The total eclipse of April 15, 2014, will be followed by another on Oct. 8, 2014, and another on April 4, 2015, and another on Sept. 28 2015.

"The most unique thing about the 2014-2015 tetrad is that all of them are visible for all or parts of the USA," says longtime NASA eclipse expert Fred Espenak.

On average, lunar eclipses occur about twice a year, but not all of them are total.

There are three types:

  • A penumbral eclipse is when the Moon passes through the pale outskirts of Earth's shadow. It's so subtle, sky watchers often don't notice an eclipse is underway.
  • A partial eclipse is more dramatic. The Moon dips into the core of Earth's shadow, but not all the way, so only a fraction of Moon is darkened.
  • A total eclipse, when the entire Moon is shadowed, is best of all. The face of the Moon turns sunset-red for up to an hour or more as the eclipse slowly unfolds.

Usually, lunar eclipses come in no particular order. A partial can be followed by a total, followed by a penumbral, and so on. Anything goes.

Occasionally, though, the sequence is more orderly. When four consecutive lunar eclipses are all total, the series is called a tetrad.

Fred Espenak
"During the 21st century, there are 9 sets of tetrads, so I would describe tetrads as a frequent occurrence in the current pattern of lunar eclipses," says Espenak. "But this has not always been the case."

"During the three hundred year interval from 1600 to 1900, for instance, there were no tetrads at all."

The April 15th eclipse begins at 2 AM Eastern time when the edge of the Moon first enters the amber core of Earth's shadow.

Totality occurs during a 78 minute interval beginning around 3 o'clock in the morning on the east coast, midnight on the west coast.

Weather permitting, the red Moon will be easy to see across the entirety of North America.

Sunday, March 30, 2014

Mazda SkyActiv 2: Petrol engine with massive fuel economy ambitions

Auto-focused sites are buzzing over a recent report in Autocar, reporting Japanese automobile manufacturer Mazda's future gasoline engine technology, which will reduce carbon dioxide emissions below the amount generated to power electric cars. noted that, while electric cars do not pump out CO2 as they travel, they have a carbon footprint created when the electric power they run on is produced.

Though not due for some years to come, the very idea of a gasoline engine efficient enough to release less carbon dioxide than an electric car was tantalizing enough to make the numerous blog and car site headlines.

Specifically, the spotlight is on advances in Mazda's SkyActiv engine technology. Mark Tisshaw, writing in Autocar, said

"So efficient is its latest internal combustion engine technology, the Japanese firm claims that it could even eclipse pure electric cars for well-to-wheel CO2 emissions, without adding expensive and heavy hybrid or plug-in hybrid components."

At Mazda, the engine of the future is called the SkyActiv-G Generation 2, a follow-up to Mazda's SkyActiv-G Generation 1.

For SkyActiv-G Generation 2, Mazda will adopt homogeneous charge compression ignition (HCCI) and an even higher compression ratio of 18:1 over SkyActiv-G Generation 1 high compression ratio of 14:1.

Mazda said on its site that increasing the compression ratio considerably improves thermal efficiency.

According to Autocar, it is likely SkyActiv-G Generation 2 technology could arrive in production before the decade is out.

For SkyActiv-G Generation 2, Mazda will adopt homogeneous charge compression ignition (HCCI) and the higher compression ratio of 18:1.

Autocar said The HCCI system works in a way similar to a diesel engine, using piston compression rather than a spark plug to ignite the mixture in the chamber.

Automotive News explained how HCCI "compresses the fuel-air mixture to such a high pressure and temperature that it ignites by itself without requiring a spark, similar to the way a diesel engine operates."

That Mazda had ambitious plans for a generation of engines in years to come that could achieve 30 percent better fuel economy than the current line of Skyactiv engines was already evident back in January this year, when Mitsuo Hitomi, in charge of powertrain development, spoke at Mazda's Yokohama technical center.

Discussing goals, Hitomi said Skyactiv 2 will focus on improved internal combustion "If we want to dramatically improve fuel economy from here, the only route is through lean burning,"

Hitomi referred also to plans for a Skyactiv 3 lineup in the future that may help Mazda comply with 2025 emissions targets.

Thursday, March 27, 2014

ESA ExoMars: Mars Landing Site selection

The ESA ExoMars "longlist". Two proposals were received for Mars' Mawrth Vallis, but these were virtually the same

The ESA has published the "longlist" of eight sites it is considering as a destination for the ExoMars rover.

The 300kg vehicle will be put on the surface of the Red Planet in January 2019 to search for evidence of past or present life.

It should operate for at least seven months and will carry a drill to probe up to 2m underground.

The sites are generally clustered in a relatively tight zone close to the equator. They are: Hypanis Vallis, Shalbatana (Simud) VallisMawrth Vallis, Oxia Planum (x2), Coogoon Valles, Oxia Palus and Southern Isidis.

The ExoMars Landing Site Selection Working Group is meeting now in Madrid to begin the process of downselection.

The teams that proposed these locations will make their case during the Spanish gathering (two, virtually identical proposals were received for Mawrth Vallis).

It is hoped to have a shortlist of no more than four locations in June or July. These will then be intensively studied, calling on new high-resolution pictures and mineralogical data acquired by satellites in orbit at Mars.

A final decision is likely to be announced in 2017. This will probably take the form of a first choice and a back-up.

We've been talking about ExoMars for a long time. The project has had several ups and downs, but it is now moving positively in the right direction.

The venture is a joint undertaking with the Russians, who, as well as providing the launch rocket in May 2018, and some of the instrumentation, will also build the landing system.

This will see the rover enter the Martian atmosphere in 2019 in a protective shell, deploying parachutes and retro-rockets to reduce the descent velocity.

The robotic vehicle will arrive at the surface on a legged lander, driving down a ramp to begin its grand traverse.

Everything hinges on a safe touchdown, of course. However, scientifically, it's vital ExoMars goes to the right place.

I have used two maps on this page to help explain how the final decision will be made.

They are both Mercator projections of Mars which will be familiar from Earth maps that also pull the 360-degree globe on to a flat surface.

For reference, I've marked the locations of the two current American rovers - Curiosity and Opportunity - on the top map.

Choosing a site is a trade-off between what's scientifically desirable and what's achievable with the available engineering.

ExoMars wants to search for life markers. Its best chance of finding these will be to go to places where there is abundant evidence for long-duration, or frequently reoccurring, water activity.

This will exist on the old terrains of Mars i.e. ones that are billions of years old.

These are places where you would hope to roll across recently exposed fine-grained sediments; the kind of clay-bearing mudstones that Curiosity has been enjoying in Gale Crater.

ESA Planck and NASA WMAP: Dark energy a mirage concealed behind phantom fields

Observations of ESA's Planck and NASA's WMAP satellites help to solve the equation of the state of dark energy. 

Credit: ESA et al.

Quintessence and phantom fields, two hypotheses formulated using data from satellites, such as ESA's Planck and NASA's Wilkinson Microwave Anisotropy Probe (WMAP), are among the many theories that try to explain the nature of dark energy.

Now researchers from Barcelona and Athens suggest that both possibilities are only a mirage in the observations and it is the quantum vacuum which could be behind this energy that moves our universe.

Cosmologists believe that some three quarters of the universe are made up of a mysterious dark energy which would explain its accelerated expansion.

The truth is that they do not know what it could be, therefore they put forward possible solutions.

One is the existence of quintessence, an invisible gravitating agent that instead of attracting, repels and accelerates the expansion of the cosmos.

WMAP Satellite Diagram
From the Classical World until the Middle Ages, this term has referred to the ether or fifth element of nature, together with earth, fire, water and air.

Another possibility is the presence of an energy or phantom field whose density increases with time, causing an exponential cosmic acceleration.

This would reach such speed that it could break the nuclear forces in the atoms and end the universe in some 20,000 million years, in what is called the Big Rip.

The experimental data that underlie these two hypotheses comes from satellites such as ESA's Planck and NASA's Wilkinson Microwave Anisotropy Probe (WMAP).

Observations from the two probes are essential for solving the so-called equation of the state of dark energy, a characterising mathematical formula, the same as that possessed by solid, liquid and gaseous states.

Now researchers from the University of Barcelona (Spain) and the Academy of Athens (Greece) have used the same satellite data to demonstrate that the behaviour of dark energy does not need to resort to either quintessence or phantom energy in order to be explained.

The details have been published in the Monthly Notices of the Royal Astronomical Society journal.

Joan Solà
"Our theoretical study demonstrates that the equation of the state of dark energy can simulate a quintessence field, or even a phantom field, without being one in reality, thus when we see these effects in the observations from WMAPPlanck and other instruments, what we are seeing is an mirage," told SINC Joan Solà, one of the authors from University of Barcelona.

Nothing fuller than the quantum vacuum
"What we think is happening is a dynamic effect of the quantum vacuum, a parameter that we can calculate," explained the researcher.

The concept of the quantum vacuum has nothing to do with the classic notion of absolute nothingness.

"Nothing is more 'full' than the quantum vacuum since it is full of fluctuations that contribute fundamentally to the values that we observe and measure," Solà pointed out.

The detailed, all-sky picture of the infant universe created from nine years of WMAP data. 

The image reveals 13.77 billion year old temperature fluctuations (shown as colour differences) that correspond to the seeds that grew to become the galaxies. 

The signal from our galaxy was subtracted using the multi-frequency data. This image shows a temperature range of ± 200 microKelvin.

Credit: NASA / WMAP Science Team

These scientists propose that dark energy is a type of dynamical quantum vacuum energy that acts in the accelerated expansion of our universe.

This is in contrast to the traditional static vacuum energy or cosmological constant.

The drawback with this strange vacuum is that it is the source of problems such as the cosmological constant, a discrepancy between the theoretical data and the predictions of the quantum theory that drives physicists mad.

"However, quintessence and phantom fields are still more problematic, therefore the explanation based on the dynamic quantum vacuum could be the more simple and natural one," concluded Solà.

More information: Spyros Basilakos, Joan Sola. "Effective equation of state for running vacuum: "mirage" quintessence and phantom dark energy". Monthly Notices of the Royal Astronomical Society 437(4), February 2014. DOI: 10.1093/mnras/stt2135

Wednesday, March 26, 2014

Asteroid Chariklo found to have two rings

Observations at many sites in South America, including ESO's La Silla Observatory, have made the surprise discovery that the remote asteroid Chariklo is surrounded by two dense and narrow rings. 

This is the smallest object by far found to have rings and only the fifth body in the Solar System, after the much larger planets Jupiter, Saturn, Uranus and Neptune, to have this feature. 

The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris. 

This artist's impression shows how the rings might look from close to the surface of Chariklo. 

Credit: ESO /L. Calçada /Nick Risinger (

Observations at many sites in South America have made the discovery that the asteroid Chariklo is surrounded by two dense and narrow rings.

This is the smallest object by far found to have rings and only the fifth body in the Solar System to have this feature.

The origin of these rings remains a mystery, but they may be the result of a collision that created a disc of debris.

The rings of Saturn are one of the most spectacular sights in the sky, and less prominent rings have also been found around the other giant planets.

Despite many careful searches, no rings had been found around smaller objects orbiting the Sun in the Solar System.

Now observations of the distant minor planet (10199) Chariklo as it passed in front of a star have shown that this object too is surrounded by two fine rings.

"We weren't looking for a ring and didn't think small bodies like Chariklo had them at all, so the discovery, and the amazing amountof detail we saw in the system, came as a complete surprise!" says Felipe Braga-Ribas (Observatório Nacional/MCTI, Rio de Janeiro, Brazil) who planned the observation campaign and is lead author on the new paper.

Chariklo is the largest member of a class known as the Centaurs and it orbits between Saturn and Uranus in the outer Solar System.

Predictions had shown that it would pass in front of the star UCAC4 248-108672 on 3 June 2013, as seen from South America.

Astronomers using telescopes at seven different locations, including the 1.54-metre Danish and TRAPPIST telescopes at ESO's La Silla Observatory in Chile, were able to watch the star apparently vanish for a few seconds as its light was blocked by Chariklo—an occultation.

Chariklo is a comet-like miniature planet located between Saturn and Uranus. 

It has a diameter of 250 km and new observations show that there are two rings of ice particles and pebbles. 

This is the first time such a small celestial body with rings has been observed. 

Credit: Lucie Maquet

But they found much more than they were expecting. A few seconds before, and again a few seconds after the main occultation there were two further very short dips in the star's apparent brightness.

Something around Chariklo was blocking the light! By comparing what was seen from different sites the team could reconstruct not only the shape and size of the object itself but also the shape, width, orientation and other properties of the newly discovered rings.

The team found that the ring system consists of two sharply confined rings only seven and three kilometres wide, separated by a clear gap of nine kilometres—around a small 250-kilometre diameter object orbiting beyond Saturn.

"For me, it was quite amazing to realise that we were able not only to detect a ring system, but also pinpoint that it consists of two clearly distinct rings," adds Uffe Gråe Jørgensen (Niels Bohr Institute, University of Copenhagen, Denmark), one of the team.

"I try to imagine how it would be to stand on the surface of this icy object, small enough that a fast sports car could reach escape velocity and drive off into space, and stare up at a 20-kilometre wide ring system 1000 times closer than the Moon."

The special camera is Irish, and the software programs were specially developed over five years at the Niels Bohr Institute by three astronomers and two Ph.D. students. 

It takes 40 images per second and the resolution is just as fantastic as if it was out in space. 

It is now sitting on the Danish telescope at the La Silla Observatory in Chile. 

The main purpose of the camera is to observe exoplanets, which are planets orbiting a star other than the Sun, but the sensitive camera has also shown its strength for making extremely precise observations of other objects. 

Credit: Jesper Skottfelt, Niels Bohr Institute

Although many questions remain unanswered, astronomers think that this sort of ring is likely to be formed from debris left over after a collision. It must be confined into the two narrow rings by the presence of small putative satellites.

"So, as well as the rings, it's likely that Chariklo has at least one small moon still waiting to be discovered," adds Felipe Braga Ribas.

The rings may prove to be a phenomenon that might in turn later lead to the formation of a small moon. Such a sequence of events, on a much larger scale, may explain the birth of our own Moon in the early days of the Solar System, as well as the origin of many other satellites around planets and asteroids.

The leaders of this project are provisionally calling the rings by the nicknames Oiapoque and Chuí, two rivers near the northern and southern extremes of Brazil.

More information: Paper:

Gemini Observatory: A new object at the edge of our Solar System

These are the discovery images of 2012 VP113, affectionately called 'Biden' because of the VP in the provisional name. 

It has the most distant orbit known in our Solar System. 

Three images of the night sky, each taken about two hours apart, were combined into one.

The first image was artificially colored red, second green and third blue. 

2012 VP113 moved between each image as seen by the red, green and blue dots. 

The background stars and galaxies did not move and thus their red, green and blue images combine to showup as white sources. 

Credit: Scott Sheppard and Chad Trujillo

The Solar System has a new most-distant member, bringing its outer frontier into focus.

New work from Scott Sheppard of Carnegie and Chadwick Trujillo of the Gemini Observatory reports the discovery of a distant dwarf planet, called 2012 VP113, which was found beyond the known edge of the Solar System.

This is likely one of thousands of distant objects that are thought to form the so-called inner Oort cloud.

What's more, their work indicates the potential presence of an enormous planet, perhaps up to 10 times the size of Earth, not yet seen, but possibly influencing the orbit of 2012 VP113, as well as other inner Oort cloud objects.

Their findings are published March 27 in Nature.

The paper is Sheppard and Trujillo, “A Sedna-like body with a perihelion of 80 astronomical units,” Nature 507 (27 March, 2014), 471-474.

The known Solar System can be divided into three parts: the rocky planets like Earth, which are close to the Sun; the gas giant planets, which are further out; and the frozen objects of the Kuiper belt, which lie just beyond Neptune's orbit.

Beyond this, there appears to be an edge to the Solar System where only one object, Sedna, was previously known to exist for its entire orbit.

But the newly found 2012 VP113 has an orbit that stays even beyond Sedna, making it the furthest known in the Solar System.

"This is an extraordinary result that redefines our understanding of our Solar System," says Linda Elkins-Tanton, director of Carnegie's Department of Terrestrial Magnetism.

These images show the discovery of the new inner Oort cloud object 2012 VP113 taken about 2 hours apart on UT November 5, 2012. 

The motion of 2012 VP113 clearly stands out compared to the steady state background stars and galaxies. 

Credit: Scott S. Sheppard: Carnegie Institution for Science

Sedna was discovered beyond the Kuiper Belt edge in 2003, and it was not known if Sedna was unique, as Pluto once was thought to be before the Kuiper Belt was discovered.

With the discovery of 2012 VP113 it is now clear Sedna is not unique and is likely the second known member of the hypothesized inner Oort cloud, the likely origin of some comets.

2012 VP113's closest orbit point to the Sun brings it to about 80 times the distance of the Earth from the Sun, a measurement referred to as an astronomical unit or AU.

For context, the rocky planets and asteroids exist at distances ranging between .39 and 4.2 AU.

Gas giants are found between 5 and 30 AU, and the Kuiper belt (composed of thousands of icy objects, including Pluto) ranges from 30 to 50 AU.

In our solar system there is a distinct edge at 50 AU. Only Sedna was known to stay significantly beyond this outer boundary at 76 AU for its entire orbit.

More information: Paper:

New storms on Jupiter look like Mickey Mouse

A full view of Jupiter on February 25, 2014 showing several features including three storms that in combination look like Mickey Mouse. 

Credit: Damian Peach

We told you this was going to be a good season to observe Jupiter, and astro-photographers in the northern hemisphere have been making the most of this time of opposition where Jupiter has been riding high in the sky.

What we didn't know was that there was going to be a familiar face staring back at us.

A combination of three storms has been noted throughout this Jupiter observing season for its resemblance to Mickey Mouse's face (at least in outline).

Damian has also put together a stunning movie (below) showing about three hours of rotation of the king of the planets.

Damian explained the Mickey Mouse storms are two anticyclones (high pressure regions) that form the ears while a longer elongated cyclone (low pressure) forms the face.

The abundance of storms on Jupiter are a result of the planet's dense atmosphere of hydrogen and helium and large gravitational field. Storms on this planet are likely the strongest in the Solar System.

Jupiter reached its most northern point for 2014 at a declination of +23.3 degrees on March 11, but it's still easily visible since it is the brightest starlike object in the evening sky.

Jupiter’s Great Red Spot and the ‘Mickey Mouse’ storms on February 25, 2014. 

Credit: Damian Peach.

NASA LRO: Wet or Dry Moon

The Moon's status as a "dry" rock in space has long been questioned. Competing theories abound as to the source of the H20 in the lunar soil, including delivery of water to the Moon by comets.

This week, Tartèse et al announced in Geology that new analyses of lunar soil samples demonstrates that basalts from the Moon's mantle contain hydrogen from water indigenous to Earth.

According to the authors, their work is "challenging the paradigm of a "dry" Moon, and arguing that some portions of the lunar interior are as wet as some regions of the Earth's mantle."

This video from NASA Goddard shows how NASA’s Lunar Reconnaissance Orbiter (LRO) is helping scientists understand where water is likely to exist on the south pole of the Moon. 

Credit: NASA Goddard on YouTube

Since the 1960's, scientists have suspected that frozen water could survive in cold, dark craters at the Moon's poles.

While previous lunar missions have detected hints of water on the Moon, new data from the Lunar Reconnaissance Orbiter (LRO) pinpoints areas near the south pole where water is likely to exist.

The key to this discovery is hydrogen, the main ingredient in water: LRO uses its Lunar Exploration Neutron Detector (LEND), to measure how much hydrogen is trapped within the lunar soil.

By combining years of LEND data, scientists see mounting evidence of hydrogen-rich areas near the Moon's south pole, strongly suggesting the presence of frozen water.

More information: Romain Tartèse, Mahesh Anand, Francis M. McCubbin, Stephen M. Elardo, Charles K. Shearer, and Ian A. Franchi. "Apatites in lunar KREEP basalts: The missing link to understanding the H isotope systematics of the Moon." Geology, G35288.1, first published on February 25, 2014, DOI: 10.1130/G35288.1

ESA Sentinel-1: Environmental Monitoring Satellite fuelled, pressurised and ready for launch

ESA’s Sentinel-1A, the first satellite dedicated to Europe’s environmental monitoring Copernicus programme has been fuelled and pressurised, ready for its launch on 3 April.

Since its arrival in Kourou, French Guiana a month ago, Sentinel-1A has been put through a series of stringent tests.

As well as ensuring that this new satellite hadn’t incurred any damage during transit from France, the tests included the lengthy process making sure its batteries charge from the solar wings and then release energy to the satellite as needed, as they would do in space.

The latest preparations have focused on fuelling.

As this is an extremely hazardous task, the fuelling team has to wear special ‘scape suits’.

Pre-Launch Operations crew togged up in ‘scape suits’

Marking a milestone on the road to launch, the team finished loading the fuel last Friday and pressurised the tanks yesterday.

Svein Lokas, ESA’s Sentinel-1A Launch Campaign Manager, said, “The various teams have been working flat out to thoroughly test the satellite and all its components.

“We are very happy and relieved that we have reached this important milestone.”

ESA’s Sentinel-1 Project Manager, Ramón Torres, added, “After being involved in the Sentinel-1 mission for more than seven years, these last few days before launch are very rewarding.”

Assembling Soyuz

“It is thanks to the outstanding technical excellence and collaborative efforts from industry and ESA that have brought us to this point, and we all look forward to a successful launch on 3 April.

“Once safely in orbit around Earth, this new satellite will provide essential radar imagery for Europe’s Copernicus programme – a programme that will make a step change in the way we care for our planet.”

Sentinel-1 is defined by its advanced radar. Able to scan Earth’s surface no matter what the weather and regardless of whether it is day or night, it will be vital for numerous practical applications.

In crisis situations, it will be used for rapid response to disasters such as floods and earthquakes. Its radar will routinely monitor shipping zones, map sea ice and provide information on winds and waves for marine traffic, track changes in the way land is being used, and monitor subsidence.