Hubble maps temperature, water vapour on wild exoplanet

An artist's conception of exoplanet WASP-43b orbiting an orange dwarf star roughly 260 light-years from Earth. 

About twice as massive as Jupiter, WASP-43b heats up to about 3,000 degrees Fahrenheit during its closest passes by its star, a temperature hot enough to melt steel. 

Credit: NASA, ESA

A team of scientists including a University of Colorado Boulder professor used NASA's Hubble Space Telescope to make the most detailed global map yet of the glow from a giant, oddball planet orbiting another star, an object twice as massive as Jupiter and hot enough to melt steel.

The Hubble observations show that the planet, called WASP-43b, is no place to call home.

It's a world of extremes, where winds howl at the speed of sound from a 3,000-degree-Fahrenheit dayside to a pitch-black nightside when temperatures plunge to a relatively cool 1,000 degrees Fahrenheit, still hot enough to melt silver.

The map provides information about temperatures at different layers of the planet's atmosphere and traces the amount and distribution of water present.

The findings have ramifications for understanding the atmospheric dynamics and the formation of giant planets like Jupiter, said team leader Jacob Bean of the University of Chicago.

"These measurements have opened the door for a new kind of comparative planetology."

A paper on the subject was published online Oct. 9 in Science Express.

As a ball of predominately hot hydrogen gas, there are no surface features on WASP-43b like oceans or continents that can be used to track its rotation, said CU-Boulder Assistant Professor Jean-Michel Désert, second author on the new study.

Only the drastic temperature difference between the dayside and nightside can be used by remote observers to mark the passage of a day on the strange, gaseous planet, he said.

"WASP-43b is extreme in many ways," said Désert. "It's the size of Jupiter with twice its mass. Its orbit around its host star, called an orange dwarf, takes only about 19 hours – the blink of an eye compared to the 365 days it takes Earth to orbit the sun."

Désert said the study is compelling to those trying to understand planetary formation. "Basically it is like taking a planet like Jupiter into a giant laboratory, then warming it at such a high temperature that all of the atoms and molecules comprising its atmosphere are in a gas phase."

Another bizarre thing about WASP-43b is its orbit. It orbits so close to its host star it always "shows" the same hemisphere, a phenomena similar to the orbit of the moon around Earth that is known as known as "tidal locking."

Discovered in 2011, WASP-43b is 260 light-years away, too distant to be photographed, but because its orbit is observed "edge-on" to Earth, astronomers detected it by observing regular dips in the light of its parent star as the planet passed in front of it, said Désert of CU-Boulder's Department of Astrophysical and Planetary Sciences.

More information: "Thermal structure of an exoplanet atmosphere from phase-resolved emission spectroscopy," by K.B. Stevenson et al. Science, 2014. www.sciencemag.org/lookup/doi/… 1126/science.1256758

ESA Rosetta: OSIRIS instrument maps comet 67/P

Several morphologically different regions are indicated in this preliminary map, which is oriented with the comet’s ‘body’ in the foreground and the ‘head’ in the background.

Credits: ESA/Rosetta/MPS for OSIRIS Team MPS /UPD /LAM /IAA /SSO /INTA /UPM /DASP /IDA

The map and new high-resolution images from the OSIRIS instrument were presented during the Rosetta special session at EPSC today.

With various areas dominated by cliffs, depressions, craters, boulders or even parallel grooves, 67P/C-G displays a multitude of different terrains. Some areas even appear to have been shaped by the comet’s activity.

This preliminary analysis provides the basis for a detailed scientific description of the comet’s surface, but a substantial amount of work involving more detailed OSIRIS images and data from other Rosetta instruments lies ahead to determine what each region represents in terms of their composition and evolution.

Jagged cliffs and prominent boulders are visible in this image taken by OSIRIS on 5 September 2014 from a distance of 62 kilometres from comet 67P/Churyumov-Gerasimenko. 

The left part of the image shows a side view of the comet’s 'body', while the right is the back of its 'head'. One pixel corresponds to 1.1 metres.

Credits: ESA/Rosetta/MPS for OSIRIS Team MPS /UPD /LAM /IAA /SSO /INTA /UPM /DASP /IDA

As both 67P/C-G and Rosetta travel closer to the Sun over the next months, the OSIRIS team will monitor the surface looking for changes.

While the scientists do not expect the borderlines of the comet’s regions to vary dramatically during this one passage around the Sun, more subtle transformations of the surface may nevertheless help to explain how cometary activity created such a breath-taking world.

ESA Satellite Sentinel-1A maps out Napa Valley earthquake

A radar interferogram from Sentinel-1A showing how the ground moved in the Napa Valley earthquake. 

Each coloured fringe is caused by a change in distance between the ground and the satellite of about 3cm. 

The extent of the ground deformation in the interferogram shows that the fault slip which occurred in this earthquake continues further north than the extent of the mapped rupture at the surface. 

Credit: Copernicus data (2014) /ESA/PPO.labs-Norut–COMET-SEOM Insarap study

Scientists have used a new Earth-observation satellite called Sentinel-1A to map the ground movements caused by the earthquake that shook up California's wine-producing Napa Valley on 24 August 2014.

This is the first earthquake to be mapped by the European Space Agency's (ESA) new satellite and demonstrates the capabilities of the Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics (COMET) in analysing its observations quickly.

COMET Director, Professor Tim Wright, from the School of Earth and Environment at the University of Leeds, said: "This successful demonstration of Sentinel-1A marks the beginning of a new era for our ability to map earthquakes from space.

COMET scientists are building a system that will routinely provide results for all continental earthquakes, as well as mapping the slow warping of the ground surface that leads to earthquakes."

Professor Andy Hooper, a member of the COMET team from the School of Earth and Environment at the University of Leeds, added: "This satellite represents a sea change in the way we will be able to monitor catastrophic events, such as earthquakes and volcanic eruptions, due to its systematic observation strategy."

Sentinel-1A was launched on 3 April 2014, but it only reached its final operational orbit on 7 August. The pre-earthquake image was acquired on that day.

By comparing it with an image acquired on 31 August, COMET collaborators Dr Yngvar Larsen, from the research institute Norut in Norway, and Dr Petar Marinkovic, from PPO.labs in the Netherlands, created a map of the surface deformation, called an 'interferogram', caused by the magnitude 6.0 earthquake.

The images are being used by scientists on the ground to help them map the surface rupture.

Austin Elliott, a PhD student at the University of California, Davis, who has been among the team mapping the earthquake rupture on the ground said: "The data from satellites are invaluable for completely identifying the surface break of the earthquake, deformation maps from satellite imagery guide us to places where rupture has not yet been mapped."

Although the Sentinel-1 satellite system, which will also include the future Sentinel-1B satellite, is still being tested and commissioned, ESA was able to ensure data covering the earthquake were acquired, and provide this to the science team rapidly.

When the Sentinel-1 constellation is fully operational, the average time delay between an earthquake and a radar acquisition will only be a few days, which will mean the results will also be useful for helping with humanitarian responses on the ground.

The interferogram clearly confirms that the West Napa Fault was responsible for the earthquake. This fault had not been identified as being particularly hazardous prior to the event.

ESA's SMART-1 Advanced Moon Imaging Experiment (AMIE) maps Lunar North Pole

Credit: ESA

This mosaic of the lunar north pole was obtained with images taken by the Advanced Moon Imaging Experiment (AMIE) on board ESA's SMART-1.

The pictures were taken between May 2005 and February 2006, during different phases of the mission.

The mosaic, composed of about 30 images, covers an area of about 800 by 600 km.

The lunar near-side facing Earth is at the bottom of the map, while the far-side is at the top.

A number of interesting lunar craters are indicated.

Peary, visible in the centre of the mosaic, is the crater closest to the lunar north pole.

It is nearly circular (about 73 km across), with an eroded rim and a relatively flat crater floor marked by smaller craters inside.

The southern part of its interior is permanently in shadow, making it difficult to image.

It was named after the American polar explorer Robert Edwin Peary (1856-1920).

Byrd, in the bottom-centre part of the mosaic, is a crater about 94 km across. Its rim is eroded, and its floor was once flooded by lava which left it nearly flat.

It was named after the American polar explorer Richard Evelyn Byrd (1888-1957). Hermite is an impact crater about 104 km across, located along the northern lunar limb, close to the north pole of the Moon.

From Earth, this crater is viewed nearly from the side, illuminated by oblique sunlight. It is eroded and has a rugged outer rim, incised from past impacts. Its interior forms a wide plain marked by numerous tiny craters and low hills.

Sylvester, about 58 km in diameter, is an almost-circular lunar impact crater visible on the left-hand side of the image.

It is located along the northern limb, and has a sharp-edged rim. Due its location, it only receives sunlight at a low angle.

It is named after the English mathematician James Joseph Sylvester (1814-1897).

Plaskett crater, about 109 km across, is located on the northern far-side of the Moon, 200 km from the north pole, near the lunar limb.

It receives sunlight at a low angle.

When obtaining the images, SMART-1 was flying over the north pole at a distance of about 3000 km, allowing large-field (about 300 km across) and medium-resolution views (300 m/pixel).

Each individual image includes areas imaged with colour filters and a more exposed area.

The differences have been corrected accordingly to obtain this mosaic. 

ESA CryoSat maps largest-ever flood beneath Antarctica

Location of the crater in Victoria Land, East Antarctica at about 73ºS and 156ºE. The colour scale shows height derived from CryoSat data. The crater is located within the white box. Credit: ESA/M. McMillan

ESA's CryoSat satellite has found a vast crater in Antarctica's icy surface. Scientists believe the crater was left behind when a lake lying under about 3 km of ice suddenly drained.

Far below the thick ice sheet that covers Antarctica, there are lakes of fresh water without a direct connection to the ocean.

These lakes are of great interest to scientists who are trying to understand water transport and ice dynamics beneath the frozen Antarctic surface – but this information is not easy to obtain.

One method is to drill holes through kilometres of ice to the water – a difficult endeavour in the harsh conditions of the polar regions.

But instead of looking down towards the ice, a team of European scientists is looking to the sky to improve our understanding of subglacial water and its transport.

By combining new measurements acquired by CryoSat with older data from NASA's ICESat satellite, the team has mapped the large crater left behind by a lake, and even determined the scale of the flood that formed it.

From 2007 to 2008, six cubic kilometres of water – about the same amount that is stored in Scotland's Loch Ness – drained from the lake, making it the largest event of its kind ever recorded.

That amount of water equals a tenth of the melting that occurs beneath Antarctica each year.

Since the end of 2008, the lake appears to be refilling but six times slower than it drained. It could take decades to reform.

Dark Side: Australian team maps Moon's hidden craters

Some 66 of the possible 280 additional craters on the Moon, in a photo from Western Australia's Curtin University in Perth released on June 18, 2013. 

Australian scientists Tuesday said they had identified a possible 280 additional craters on the Moon, a finding they said could shed light on the history of the Earth's natural satellite.

Australian scientists Tuesday said they had identified a possible 280 additional craters on the Moon, a finding they said could shed light on the history of the Earth's natural satellite.

By combining gravity and topography data collected by satellites, the scientists from Curtin University in Western Australia were able to use computer modelling to at first identify two basins on the far side of the Moon.

They later developed a high-resolution image to find a total of 280 "candidate basins" which they suspect are craters.

Will Featherstone

"There are many more (craters) that have been mapped from optical observations or from just the shape of the topography," researcher Will Featherstone told reporters.

"So there's many, many craters that were already known, we've just been able to apply this technique to enhance the ones that aren't so easy to see.

"What we have been able to use is the topography and the gravity together to get a stronger indication that there is something there that needs further investigation."

Featherstone said the researchers looked at the lunar surface on both the near and far sides of the Moon, the dark side being more challenging because satellites cannot be tracked from Earth when they are on that side.

To get around this, the researchers used data gathered from a mission which used multiple satellites which were tracking each other as they circled the Moon.

"So when the satellite orbiting the Moon went behind the far side and they couldn't be seen from Earth, they could be seen by other satellites," he said.

Featherstone said of the 280 possible craters, the researchers had classified 66 of them as distinctly visible according to both gravity and topography.

"Scientists can, instead of looking at every square inch of the Moon looking for basins, they can target these areas," he said.

"It just helps investigations of the Moon and the history of the Moon and the solar system," he added.

The team has also done some work on the gravity of Mars and Featherstone said other data sets were also available for Venus and other planets.

He said scientists were optimistic about further discoveries from applying their techniques to new gravity data from NASA's GRAIL mission, which ended in late 2012 when the two satellites - named Ebb and Flow - were deliberately crashed on the Moon.

Hubble maps 3-D structure of ejected material around erupting star

Hubble's Wide Field Camera 3 imaged the double-star system T Pyxidis, or T Pyx, over a four-month period. 

T Pyx is a recurrent nova, erupting every 12 to 50 years. 

T Pyx's latest outburst was in April 2011. The star is the white blob in the middle of each image. 

Credit: NASA, ESA, A. Crotts, J. Sokoloski, and H. Uthas (Columbia University), and S. Lawrence (Hofstra University)

A flash of light from a stellar outburst has provided a rare look at the 3-D structure of material ejected by an erupting nova.

Astronomers used NASA's Hubble Space Telescope to observe the light emitted by the close double-star system T Pyxidis, or T Pyx, a recurring nova, during its latest outburst in April 2011.

A nova erupts when a white dwarf, the burned-out core of a sun-like star, has siphoned off enough hydrogen from a companion star to trigger a thermonuclear runaway.

As hydrogen builds up on the surface of the white dwarf, it becomes hotter and denser until it detonates like a colossal hydrogen bomb, leading to a 10,000-fold increase in brightness in a little more than one day.

Nova explosions are extremely powerful, equal to a blast of one million billion tons of dynamite. T Pyx erupts every 12 to 50 years.

Contrary to some predictions, the astronomers were surprised to find the ejecta from earlier outbursts stayed in the vicinity of the star and formed a disk of debris around the nova.

The discovery suggests material continues expanding outward along the system's orbital plane, but it does not escape the system.

Arlin Crotts

"We fully expected this to be a spherical shell," says Arlin Crotts of Columbia University, a member of the research team.

"This observation shows it is a disk, and it is populated with fast-moving ejecta from previous outbursts."

Team member Stephen Lawrence of Hofstra University in Hempstead, N.Y., will present the results Tuesday at the American Astronomical Society meeting in Indianapolis.

Team member Jennifer Sokoloski, also of Columbia University and co-investigator on the project, suggests these data indicate the companion star plays an important role in shaping how material is ejected, presumably along the system's orbital plane, creating the pancake-shaped disk.

The disk is tilted about 30 degrees from face-on toward Earth.

Stephen Lawrence

Using Hubble's Wide Field Camera 3, the team took advantage of the blast of light emitted by the erupting nova to trace the light's path as it lit up the disk and material from previous ejecta.

The disk is so vast, about a light-year across, that the nova's light cannot illuminate all of the material at once.

Instead, the light sweeps across the material, sequentially illuminating parts of the disk, a phenomenon called a light echo.

The light reveals which parts of the disk are nearer to Earth and which sections are farther away. By tracing the light, the team assembled a 3-D map of the structure around the nova.

"We've all seen how light from fireworks shells during the grand finale will light up the smoke and soot from shells earlier in the show," Lawrence said.

"In an analogous way, we're using light from T Pyx's latest outburst and its propagation at the speed of light to dissect its fireworks displays from decades past."

Although astronomers have witnessed light propagating through material surrounding other novae, this is the first time the immediate environment around an erupting star has been studied in three dimensions.

The team's results will appear online June 5 and will be published in the June 20, 2013, issue of the Astrophysical Journal Letters. 

ESA Planck satellite: Maps detail Universe's ancient light

The map shows tiny deviations from the average background temperature, where blue is slightly cooler and red is slightly warmer. 

The cold spots are where matter was more concentrated and later collapsed under gravity to form stars and galaxies. 

Image: ESA/Planck Collaboration

A spectacular new map of the "oldest light" in the sky has just been released by the European Space Agency.

Scientists say its mottled pattern is an exquisite confirmation of our Big-Bang model for the origin and evolution of the Universe.
But there are features in the picture, they add, that are unexpected and will require ideas to be refined.

The map was assembled from 15 months' worth of data acquired by the 600m-euro (£515m) Planck space telescope.

It details what is known as the cosmic microwave background, or CMB - a faint glow of microwave radiation that pervades all of space.

Its precise configuration, visible in the new Planck data, is suggestive of a cosmos that is slightly older than previously thought - one that came into existence 13.82 billion years ago.

This is an increase of about 50 million years on earlier calculations.

The map's pattern also indicates a subtle adjustment is needed to the Universe's inventory of contents.

It seems there is slightly more matter out there (31.7%) and slightly less "dark energy" (68.3%), the mysterious component thought to be driving the cosmos apart at an accelerating rate.

Planck is the third western satellite to study the CMB. The two previous efforts - COBE and WMAP - were led by the US space agency (Nasa). The Soviets also had an experiment in space in the 1980s that they called Relikt-1.

• The CMB's temperature fluctuations are put through a number of statistical analyses
• Deviations can be studied as a function of their size on the sky - their angular scale
• When compared to best-fit Big Bang models, some anomalies are evident
• One shows the fluctuations on the biggest scales to be weaker than expected
• Theorists will need to adjust their ideas to account for these features

The CMB is the light that was finally allowed to spread out across space once the Universe had cooled sufficiently to permit the formation of hydrogen atoms - about 380,000 years into the life of the cosmos.

It still bathes the Earth in a near-uniform glow at microwave frequencies, and has a temperature profile that is just 2.7 degrees above absolute zero.

But it is possible to detect minute deviations in this signal, and these fluctuations - seen as mottling in the map - are understood to reflect the differences in the density of matter when the light parted company and set out on its journey all those years ago

The fluctuations can be thought of as the seeds for all the structure that later developed in the cosmos - all the stars and galaxies

Scientists subject the temperature deviations to a range of statistical analyses, which can then be matched against theoretical expectations.

This allows them to rule in some models to explain the origin and evolution of the cosmos, while ruling out a host of others.

The team that has done this for Planck's data says the map is an elegant fit for the standard model of cosmology - the idea that the Universe started in a hot, dense state in an incredibly small space, and then expanded and cooled.

At a fundamental level, it also supports an "add-on" to this Big Bang theory known as inflation, which postulates that in the very first moments of its existence the Universe opened up in an exponential manner - faster than light itself.

But because Planck's map is so much more detailed than anything previously obtained, it is also possible to see some anomalies in it.

Star Maps From Mobile App Maker Brings Astronomy to the Masses

Skywatching enthusiasts, rejoice! The makers of a popular astronomy app have released a series of free star maps and new educational tools to help both casual and more experienced stargazers learn more about the cosmos, the app's designers said.

Starmap is providing users with free customizable regional star maps and an infographic that illustrates the history of astronomy, and includes resources can be downloaded from the company's website.

The resources join the ranks of a growing field of space-themed apps for digital devices.

"You can download the map month-by-month for the Northern and Southern hemisphere, and you can see the exact times on a list of what can be seen with the naked eye or with telescopes," Frederick Descamps, an astronomer and the creator of the Starmap mobile app, told SPACE.com.

Once users select their hemisphere, region and desired time of night, the map is automatically generated and highlights constellations, planets, moon phases and other cosmic objects that could be visible.

The maps will also separate objects that can be seen with the naked eye, binoculars, small telescopes and larger telescopes.

GPS with Android and WiFi on its way

The world's first handheld GPS to use the Android mobile operating system is here.

The All Sports GPS from Holux is also the first handheld unit with WiFi capability.

The idea is to fuse smartphone capability into a handheld GPS, allowing users to download GPS apps directly without having to hookup to a computer.
 
The All Sports GPS is a cooperative effort between Taiwan's Holux, which manufactures GPS products, and Satski, a Canadian company best known for its winter sports apps.

So, it's not surprising that the GPS will come pre-loaded with the SatSki app and a companion suite that includes other sports apps for golf, biking, running and geo-caching, among other activities.

The apps provide all sorts of speed, distance, real-time location and navigation information. For winter sports fans, the Satski app uses resort trail maps.

There's also Facebook and Twitter integration and on online community at luvthesnow.com to share and boast about your greatest runs.

Another app included in the package is All Sports Maps, which allows users to download live maps, including Google, Nokia OVI, Open Street and Open Cycle, for later offline use, all for free.

Similar apps in the Android Market can run you as much as ten US dollars for something well-suited to backcountry use, out of the range of a data connection.

SatSki promises that the All Sports GPS will be a "rugged, highly sensitive IPX 6-rated unit" that also supports Bluetooth health monitor accessories. No word on an exact release date or pricing for the device, but the company promises it is "coming soon."

NASA Gravity Lens: Bending the Light

This image of galaxy cluster MACS J1206.2-0847 (or MACS 1206 for short) is part of a broad survey with NASA's Hubble Space Telescope.

The distorted shapes in the cluster are distant galaxies from which the light is bent by the gravitational pull of an invisible material called dark matter within the cluster of galaxies.

This cluster is an early target in a survey that will allow astronomers to construct the most detailed dark matter maps of more galaxy clusters than ever before.

These maps are being used to test previous, but surprising, results that suggest that dark matter is more densely packed inside clusters than some models predict. This might mean that galaxy cluster assembly began earlier than commonly thought.

The multi-wavelength survey, called the Cluster Lensing And Supernova survey with Hubble (CLASH), probes, with unparalleled precision, the distribution of dark matter in 25 massive clusters of galaxies. So far, the CLASH team has completed observations of six of the 25 clusters.

Dark matter makes up the bulk of the universe's mass, yet it can only be detected by measuring how its gravity tugs on visible matter and warps space like a fun-house mirror so that the light from distant objects is distorted.

Galaxy clusters like MACS 1206 are perfect laboratories for studying dark matter's gravitational effects because they are the most massive structures in the universe. Because of their heft, the clusters act like giant cosmic lenses, magnifying, distorting and bending any light that passes through them — an effect known as gravitational lensing.

MACS 1206 lies 4.5 billion light-years from Earth. Hubble's keen vision helped CLASH astronomers uncover 47 multiple images of 12 newly identified faraway galaxies. Finding so many multiple images in a cluster is a unique capability of Hubble, and the CLASH survey is optimized to find them. The new observations build on earlier work by Hubble and ground-based telescopes.

The era when the first clusters formed is not precisely known, but is estimated to be at least 9 billion years ago and possibly as far back as 12 billion years ago. If most of the clusters in the CLASH survey are found to have excessively high accumulations of dark matter in their central cores, then it may yield new clues to the early stages in the origin of structure in the universe.

Image Credit: NASA, ESA, M. Postman (STScI), and the CLASH Team

Better Mars Atmosphere Maps to Come From New Mission

The Mars Climate Sounder instrument on NASA's Mars Reconnaissance Orbiter maps the vertical distribution of temperatures, dust, water vapor and ice clouds in the Martian atmosphere as the orbiter flies a near-polar orbit. A new instrument on the joint NASA-ESA ExoMars Trace Gas Orbiter will make new Mars atmosphere maps. Credit: NASA/JPL

An instrument on one of the next missions to Mars is expected to beam back daily maps of the Martian atmosphere from orbit and seek out gaseous clues in the ongoing search for any evidence of life on the Red Planet.

The ExoMars Climate Sounder will measure pole-to-pole, vertical distributions of temperature, dust, water vapor and ice clouds in the Martian atmosphere. The instrument is one of five that have been selected for the ExoMars Trace Gas Orbiter mission – a joint European-American operation, scheduled for 2016, that will seek faint gaseous signatures of potential life on Mars.

The atmospheric maps from the ExoMars Climate Sounder will provide daily profiles of the atmosphere's changing structure.

Multipurpose Mars tool
The international team of NASA and European Space Agency researchers building the new Mars orbiter has two main goals in addition to interpreting trace-gas detections.

One is to extend the climate mapping record that is currently coming from a similar instrument on NASA's Mars Reconnaissance Orbiter. That instrument, called the Mars Climate Sounder, has been working at the Red Planet since 2006.

The orbit of the Mars Reconnaissance Orbiter mission enables it to record atmospheric profiles only at about 3 p.m. and 3 a.m. during the Martian day, except near the poles. The ExoMars Trace Gas Orbiter, however, will fly an orbital pattern that allows the spacecraft to collect data at all times of the day, and at all latitudes.

"We'll fill in information about variability at different times of day, and we'll add to the number of Mars years for understanding year-to-year variability," said Tim Schofield, principal investigator for the ExoMars Climate Sounder at NASA's Jet Propulsion Laboratory in Pasadena, Calif., in a statement. "The most obvious year-to-year change is that some years have global dust storms and others don't. We'd like to learn whether there's anything predictive for anticipating the big dust storms, and what makes them so variable from year to year."

Another research goal is to provide information about the variable density of the atmosphere that could assist future landings on Mars. At any chosen landing site, atmospheric density has a tendency to change from one day to the next, which can greatly affect a spacecraft's descent.

"We want to provide background climatology for what to expect at a given site, in a given season, for a particular time of day, and also nearly real-time information for the atmospheric structure in the days leading up to the landing of a spacecraft launched after 2016," Schofield said.

One of the Earliest Primitive Maps Found in Spain

"Imagine a group of hunter-gatherers, returning to an area they had not been to for a long time. How do you find a particular cave, especially if the vegetation has changed and its entrance may be masked?" asks independent archaeologist Paul Bahn.

The answer may be that hunter-gatherers had their own maps. A team of archaeologists have matched etchings made 14,000 years ago on a polished chunk of sandstone in northern Spain to the landscape in which it was found. They claim to have the earliest known map of a region in western Europe - a prehistoric hunting map.

The rock, roughly hand-sized and 14,000 years old, bears a mess of overlapping etchings. It was found in a cave in Navarre on the southern side of the Pyrenees and it took Pilar Utrilla of the University of Zaragoza, Spain, and colleagues the better part of 10 years to disentangle the lines and make sense of them (Journal of Human Evolution, DOI: 10.1016/j.jhevol.2009.05.005).

Above recognisable depictions of reindeer, a stag and some ibex are what Utrilla's team believe is a representation of the landscape surrounding the cave. Several etched lines resemble the shapes of mountains that are visible from the cave.

Long, meandering etches match the course of a river that runs at the foot of one of the mountains and splits into two tributaries. A series of strokes that cut across the river near the mountain could represent places where it was easily crossed, or even bridges, the researchers say.

"This is a pretty spectacular find," says prehistoric archaeologist Lawrence Straus of the University of New Mexico in Albuquerque. "It may give us a glimpse into the ways in which people navigated and explained their territories."

He says the slab was etched during a period of enormous cultural activity in northern Spain. "The human range was expanding northward and population density was increasing after people nearly died off in the last glacial maximum about 20,000 to 17,000 years ago.

People were perhaps having to cooperate, carving up territories among different bands. They had to live by their wits and what the landscape provided." Strauss says engravings and paintings would have helped with territorial definition, hunting, human aggregation and mobility, and generally making sense of the world.

Female(?) Robot asks for Directions

Robots are getting better at finding their way around unknown areas, and making their own maps as they explore. But robots lost in urban areas don't need to rely on their own faculties to get from place to place, German roboticists have shown.

Their mobile robot simply rolls up to any humans nearby and asks for directions. By using that strategy, their robot has become one of the first to be properly let loose in the real world, not just carefully controlled environments.

Martin Buss's team at the Technical University of Munich dumped their mobile robot outside the university and instructed it to find its way to the Marienplatz in the centre of Munich, some 1.5 kilometres away.