How Old are Martian Gullies?

NASA - Mars Reconnaissance Orbiter (MRO) patch.

April 25, 2017

Gullies eroded into the steep inner slope of an impact crater at this location appear perfectly pristine in this image captured by NASA's Mars Reconnaissance Orbiter (MRO). Although at first glance it may appear that there are craters superimposed on the gully fans, inspection of HiRISE stereo coverage shows that the craters lie only on the pre-gully terrain.

Distinctive colors in the gully channels and alcoves offer another indication of youth and recent activity. The pre-gully landscape is covered by secondary craters from nearby Gasa Crater, estimated to be about 1 million years old. Although some have suggested that the Martian gullies are also about a million years old and formed in a different environment, we now know that they are continuing to form today.

The map is projected here at a scale of 50 centimeters (19.7 inches) per pixel. [The original image scale is 50.8 centimeters (20 inches) per pixel (with 2 x 2 binning); objects on the order of 152 centimeters (59.9 inches) across are resolved.] North is up

The University of Arizona, Tucson, operates HiRISE, which was built by Ball Aerospace & Technologies Corp., Boulder, Colo. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, California, manages the Mars Reconnaissance Orbiter Project for NASA's Science Mission Directorate, Washington.

Mars Reconnaissance Orbiter (MRO): http://www.nasa.gov/mission_pages/MRO/main/index.html

Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Univ. of Arizona.

Greetings, Orbiter.ch

New ALICE results show novel phenomena in proton collisions

CERN - European Organization for Nuclear Research logo.

24 Apr 2017

Image above: As the number of particles produced in proton collisions (the blue lines) increase, the more of these so-called strange hadrons are measured (as shown by the orange to red squares in the graph) (Image: ALICE/CERN).

In a paper published today in Nature Physics, the ALICE collaboration reports that proton collisions sometimes present similar patterns to those observed in the collisions of heavy nuclei. This behaviour was spotted through observation of so-called strange hadrons in certain proton collisions in which a large number of particles are created. Strange hadrons are well-known particles with names such as Kaon, Lambda, Xi and Omega, all containing at least one so-called strange quark. The observed ‘enhanced production of strange particles’ is a familiar feature of quark-gluon plasma, a very hot and dense state of matter that existed just a few millionths of a second after the Big Bang, and is commonly created in collisions of heavy nuclei. But it is the first time ever that such a phenomenon is unambiguously observed in the rare proton collisions in which many particles are created. This result is likely to challenge existing theoretical models that do not predict an increase of strange particles in these events.

“We are very excited about this discovery,” said Federico Antinori, Spokesperson of the ALICE collaboration. “We are again learning a lot about this primordial state of matter. Being able to isolate the quark-gluon-plasma-like phenomena in a smaller and simpler system, such as the collision between two protons, opens up an entirely new dimension for the study of the properties of the fundamental state that our universe emerged from.”

The study of the quark-gluon plasma provides a way to investigate the properties of strong interaction, one of the four known fundamental forces, while enhanced strangeness production is a manifestation of this state of matter. The quark-gluon plasma is produced at sufficiently high temperature and energy density, when ordinary matter undergoes a transition to a phase in which quarks and gluons become ‘free’ and are thus no longer confined within hadrons. These conditions can be obtained at the Large Hadron Collider by colliding heavy nuclei at high energy. Strange quarks are heavier than the quarks composing normal matter, and typically harder to produce. But this changes in presence of the high energy density of the quark-gluon plasma, which rebalances the creation of strange quarks relative to non-strange ones. This phenomenon may now have been observed within proton collisions as well.

In particular, the new results show that the production rate of these strange hadrons increases with the ‘multiplicity’ – the number of particles produced in a given collision – faster than that of other particles generated in the same collision. While the structure of the proton does not include strange quarks, data also show that the higher the number of strange quarks contained in the induced hadron, the stronger is the increase of its production rate. No dependence on the collision energy or the mass of the generated particles is observed, demonstrating that the observed phenomenon is related to the strange quark content of the particles produced. Strangeness production is in practice determined by counting the number of strange particles produced in a given collision, and calculating the ratio of strange to non-strange particles.

Enhanced strangeness production had been suggested as a possible consequence of quark-gluon plasma formation since the early eighties, and discovered in collisions of nuclei in the nineties by experiments at CERN’s Super Proton Synchrotron. Another possible consequence of the quark gluon plasma formation is a spatial correlation of the final state particles, causing a distinct preferential alignment with the shape of a ridge. Following its detection in heavy-nuclei collisions, the ridge has also been seen in high-multiplicity proton collisions at the Large Hadron Collider, giving the first indication that proton collisions could present heavy-nuclei-like properties. Studying these processes more precisely will be key to better understand the microscopic mechanisms of the quark-gluon plasma and the collective behaviour of particles in small systems.

The ALICE experiment has been designed to study collisions of heavy nuclei. It also studies proton-proton collisions, which primarily provide reference data for the heavy-nuclei collisions. The reported measurements have been performed with 7 TeV proton collision data from LHC run 1.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

Nature Physics: https://doi.org/10.1038/nphys4111

For more information about European Organization for Nuclear Research (CERN), Visit: http://home.cern/

Image, Text, Credits: CERN/Harriet Kim Jarlett.

Greetings, Orbiter.ch

SPS: the last injector back up and running

CERN - European Organization for Nuclear Research logo.

24 Apr 2017

Image above: The Super Proton Synchrotron (SPS) is the second-largest machine in CERN’s accelerator complex. (Image: Piotr Traczyk/CERN).

The Large Hadron Collider (LHC) is due to resume operation in early May 2017 and preparations are even ahead of schedule, by three days. On 21 April beams circulated in the Super Proton Synchrotron (SPS) for the first time this year. All four elements of CERN’s accelerator chain – Linear Accelerator 2 (Linac2), the Proton Synchrotron Booster (PSB), the Proton Synchrotron (PS) and the Super Proton Synchrotron – are now in operation.

Measuring nearly seven kilometres in circumference, the SPS takes particles from the PS and accelerates them to provide high-energy beams to the LHC. It also feeds the SPS North experimental area where, among others, the Common Muon and Proton Apparatus for Structure and Spectroscopy (COMPASS), and the NA61/Shine, NA62 and NA63 experiments are situated. Since June 2016 the SPS also supplies protons to a new proof-of-principle experiment – the Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE).

There were quite a few interventions in the SPS during the extended year-end technical stop (EYETS), including a massive de-cabling campaign in the PS Booster and the SPS, which has paved the way for the installation of new equipment for the LHC Injector Upgrade (LIU) project. This project is crucial to the planned increase of luminosity – number of collisions – of the High-Luminosity LHC, the future upgrade of the LHC, operational as from 2025.

Last year issues with the SPS internal beam dump limited the number of particle bunches that could be injected into the Large Hadron Collider (LHC). In response to that, a new beam dump was re-designed, produced, and successfully installed in the second week of March. This will allow the SPS to reach its full performance again for this year’s run.

Note:

CERN, the European Organization for Nuclear Research, is one of the world’s largest and most respected centres for scientific research. Its business is fundamental physics, finding out what the Universe is made of and how it works. At CERN, the world’s largest and most complex scientific instruments are used to study the basic constituents of matter — the fundamental particles. By studying what happens when these particles collide, physicists learn about the laws of Nature.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

Large Hadron Collider (LHC): http://home.cern/topics/large-hadron-collider

Super Proton Synchrotron (SPS): http://home.cern/about/accelerators/super-proton-synchrotron

CERN’s accelerator chain: http://home.cern/about/accelerators

Linear Accelerator 2 (Linac2): http://home.cern/about/accelerators/linear-accelerator-2

Proton Synchrotron Booster (PSB): http://home.cern/about/accelerators/proton-synchrotron-booster

Proton Synchrotron (PS): http://home.cern/about/accelerators/proton-synchrotron-booster

Common Muon and Proton Apparatus for Structure and Spectroscopy (COMPASS): http://home.cern/about/experiments/compass

NA61/Shine: http://home.cern/about/experiments/na61shine

NA62: http://home.cern/about/experiments/na62

NA63: http://home.cern/about/experiments/na63

Advanced Proton Driven Plasma Wakefield Acceleration Experiment (AWAKE): http://home.cern/about/experiments/awake

High-Luminosity LHC: http://hilumilhc.web.cern.ch/

For more information about European Organization for Nuclear Research (CERN), Visit: http://home.cern/

Image (mentioned), Text, Credits: CERN/Iva Raynova.

Best regards, Orbiter.ch

Cassini, Voyager Missions Suggest New Picture of Sun’s Interaction with Galaxy

NASA - Voyager 1 & 2 Mission patch / NASA - Cassini International logo / NASA - GALEX Mission patch.

April 24, 2017

New data from NASA’s Cassini mission, combined with measurements from the two Voyager spacecraft and NASA’s Interstellar Boundary Explorer, or IBEX, suggests that our sun and planets are surrounded by a giant, rounded system of magnetic field from the sun — calling into question the alternate view of the solar magnetic fields trailing behind the sun in the shape of a long comet tail.

The sun releases a constant outflow of magnetic solar material — called the solar wind — that fills the inner solar system, reaching far past the orbit of Neptune. This solar wind creates a bubble, some 23 billion miles across, called the heliosphere. Our entire solar system, including the heliosphere, moves through interstellar space. The prevalent picture of the heliosphere was one of comet-shaped structure, with a rounded head and an extended tail. But new data covering an entire 11-year solar activity cycle show that may not be the case: the heliosphere may be rounded on both ends, making its shape almost spherical. A paper on these results was published in Nature Astronomy on April 24, 2017.

“Instead of a prolonged, comet-like tail, this rough bubble-shape of the heliosphere is due to the strong interstellar magnetic field — much stronger than what was anticipated in the past — combined with the fact that the ratio between particle pressure and magnetic pressure inside the heliosheath is high,” said Kostas Dialynas, a space scientist at the Academy of Athens in Greece and lead author on the study.

Image above: New data from NASA’s Cassini, Voyager and Interstellar Boundary Explorer missions show that the heliosphere — the bubble of the sun’s magnetic influence that surrounds the inner solar system — may be much more compact and rounded than previously thought. The image on the left shows a compact model of the heliosphere, supported by this latest data, while the image on the right shows an alternate model with an extended tail. The main difference is the new model’s lack of a trailing, comet-like tail on one side of the heliosphere. This tail is shown in the old model in light blue. Images Credits: Dialynas, et al. (left); NASA (right).

An instrument on Cassini, which has been exploring the Saturn system over a decade, has given scientists crucial new clues about the shape of the heliosphere’s trailing end, often called the heliotail. When charged particles from the inner solar system reach the boundary of the heliosphere, they sometimes undergo a series of charge exchanges with neutral gas atoms from the interstellar medium, dropping and regaining electrons as they travel through this vast boundary region. Some of these particles are pinged back in toward the inner solar system as fast-moving neutral atoms, which can be measured by Cassini.

“The Cassini instrument was designed to image the ions that are trapped in the magnetosphere of Saturn,” said Tom Krimigis, an instrument lead on NASA’s Voyager and Cassini missions based at Johns Hopkins University’s Applied Physics Laboratory in Laurel, Maryland, and an author on the study. “We never thought that we would see what we’re seeing and be able to image the boundaries of the heliosphere.”

Because these particles move at a small fraction of the speed of light, their journeys from the sun to the edge of the heliosphere and back again take years. So when the number of particles coming from the sun changes — usually as a result of its 11-year activity cycle — it takes years before that’s reflected in the amount of neutral atoms shooting back into the solar system.

Images above: Many other stars show tails that trail behind them like a comet’s tail, supporting the idea that our solar system has one too. However, new evidence from NASA’s Cassini, Voyager and Interstellar Boundary Explorer missions suggest that the trailing end of our solar system may not be stretched out in a long tail. From top left and going counter clockwise, the stars shown are LLOrionis, BZ Cam and Mira. Images Credits: NASA/HST/R.Casalegno/GALEX.

Cassini’s new measurements of these neutral atoms revealed something unexpected — the particles coming from the tail of the heliosphere reflect the changes in the solar cycle almost exactly as fast as those coming from the nose of the heliosphere.

“If the heliosphere’s ‘tail’ is stretched out like a comet, we’d expect that the patterns of the solar cycle would show up much later in the measured neutral atoms,” said Krimigis.

But because patterns from solar activity show just as quickly in tail particles as those from the nose, that implies the tail is about the same distance from us as the nose. This means that long, comet-like tail that scientists envisioned may not exist at all — instead, the heliosphere may be nearly round and symmetrical. 

A rounded heliosphere could come from a combination of factors. Data from Voyager 1 show that the interstellar magnetic field beyond the heliosphere is stronger than scientists previously thought, meaning it could interact with the solar wind at the edges of the heliosphere and compact the heliosphere’s tail.

The structure of the heliosphere plays a big role in how particles from interstellar space — called cosmic rays — reach the inner solar system, where Earth and the other planets are.

“This data that Voyager 1 and 2, Cassini and IBEX provide to the scientific community is a windfall for studying the far reaches of the solar wind,” said Arik Posner, Voyager and IBEX program scientist at NASA Headquarters in Washington, D.C., who was not involved with this study. “As we continue to gather data from the edges of the heliosphere, this data will help us better understand the interstellar boundary that helps shield the Earth environment from harmful cosmic rays.”

Related links:

Nature Astronomy on April 24, 2017: https://www.nature.com/articles/s41550-017-0115

Cassini: https://www.nasa.gov/mission_pages/cassini/main/index.html

http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Voyager: https://www.nasa.gov/mission_pages/voyager/index.html

IBEX (Interstellar Boundary Explorer): http://www.nasa.gov/mission_pages/ibex/index.html

Solar System: https://www.nasa.gov/topics/solarsystem/index.html

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Sarah Frazier/Rob Garner.

Greetings, Orbiter.ch

Cassini Completes Final -- and Fateful -- Titan Flyby

NASA - Cassini Mission to Saturn patch.

April 24, 2017

Image above: This unprocessed image of Saturn's moon Titan was captured by NASA's Cassini spacecraft during its final close flyby of the hazy, planet-sized moon on April 21, 2017. Image Credits: NASA/JPL-Caltech/Space Science Institute.

NASA's Cassini spacecraft has had its last close brush with Saturn's hazy moon Titan and is now beginning its final set of 22 orbits around the ringed planet.

The spacecraft made its 127th and final close approach to Titan on April 21 at 11:08 p.m. PDT (2:08 a.m. EDT on April 22), passing at an altitude of about 608 miles (979 kilometers) above the moon's surface.

Cassini transmitted its images and other data to Earth following the encounter. Scientists with Cassini's radar investigation will be looking this week at their final set of new radar images of the hydrocarbon seas and lakes that spread across Titan's north polar region. The planned imaging coverage includes a region previously seen by Cassini's imaging cameras, but not by radar. The radar team also plans to use the new data to probe the depths and compositions of some of Titan's small lakes for the first (and last) time, and look for further evidence of the evolving feature researchers have dubbed the "magic island."

Image above: This unprocessed image of Saturn's moon Titan was captured by NASA's Cassini spacecraft during its final close flyby of the hazy, planet-sized moon on April 21, 2017. Image Credits: NASA/JPL-Caltech/Space Science Institute.

"Cassini's up-close exploration of Titan is now behind us, but the rich volume of data the spacecraft has collected will fuel scientific study for decades to come," said Linda Spilker, the mission's project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California.

Gateway to the Grand Finale

The flyby also put Cassini on course for its dramatic last act, known as the Grand Finale. As the spacecraft passed over Titan, the moon's gravity bent its path, reshaping the robotic probe's orbit slightly so that instead of passing just outside Saturn's main rings, Cassini will begin a series of 22 dives between the rings and the planet on April 26. The mission will conclude with a science-rich plunge into Saturn's atmosphere on Sept. 15.

"With this flyby we're committed to the Grand Finale," said Earl Maize, Cassini project manager at JPL. "The spacecraft is now on a ballistic path, so that even if we were to forgo future small course adjustments using thrusters, we would still enter Saturn's atmosphere on Sept. 15 no matter what."

Cassini received a large increase in velocity of approximately 1,925 mph (precisely 860.5 meters per second) with respect to Saturn from the close encounter with Titan.

Image above: This unprocessed image of Saturn's moon Titan was captured by NASA's Cassini spacecraft during its final close flyby of the hazy, planet-sized moon on April 21, 2017. Image Credits: NASA/JPL-Caltech/Space Science Institute.

After buzzing Titan, Cassini coasted onward, reaching the farthest point in its orbital path around Saturn at 8:46 p.m. PDT (11:46 p.m. EDT) on April 22. This point, called apoapse, is where each new Cassini lap around Saturn begins. Technically, Cassini began its Grand Finale orbits at this time, but since the excitement of the finale begins in earnest on April 26 with the first ultra-close dive past Saturn, the mission is celebrating the latter milestone as the formal beginning of the finale.

Image above: Some key numbers for Cassini's Grand Finale and final plunge into Saturn. Image Credits: NASA/JPL-Caltech.

The spacecraft's first finale dive will take place on April 26 at 2 a.m. PDT (5 a.m. EDT). The spacecraft will be out of contact during the dive and for about a day afterward while it makes science observations from close to the planet. The earliest time Cassini is scheduled to make radio contact with Earth is 12:05 a.m. PDT (3:05 a.m. EDT) on April 27. Images and other data are expected to begin flowing in shortly after communication is established.

NASA VR: Cassini's Grand Finale (360 view)

More information about Cassini's Grand Finale, including image and video resources, is available at:

https://saturn.jpl.nasa.gov/grandfinale

More information about Cassini's final Titan flyby is available at: https://go.nasa.gov/2nFHaTo

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of Caltech in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. JPL designed, developed and assembled the Cassini orbiter.

More information about the Cassini mission:

http://www.nasa.gov/cassini

http://saturn.jpl.nasa.gov

http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Images (mentioned), Video (NASA), Text, Credits: NASA/Tony Greicius/JPL/Preston Dyches.

Best regards, Orbiter.ch

Dark Chasm

NASA - Cassini International logo.

April 24, 2017

The low angle of the sun over Tethys' massive canyon, Ithaca Chasma (near the terminator, at right), highlights the contours of this enormous rift.

Ithaca Chasma is up to 60 miles (100 kilometers) wide, and runs nearly three-fourths of the way around icy Tethys (660 miles or 1,062 kilometers across). The canyon has a maximum depth of nearly 2.4 miles (4 kilometers) deep.

The giant crater Odysseus -- usually one of Tethys’ most recognizable features-- is barely seen in profile along the limb, at upper left.

This view looks toward the Saturn-facing hemisphere of Tethys. North on Tethys is up and rotated 5 degrees to the left. The image was taken in green light with the Cassini spacecraft narrow-angle camera on Jan. 30, 2017.

The view was obtained at a distance of approximately 221,000 miles (356,000 kilometers) from Tethys. Image scale is 1 mile (2 kilometers) per pixel.

The Cassini mission is a cooperative project of NASA, ESA (the European Space Agency) and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.

For more information about the Cassini-Huygens mission visit https://saturn.jpl.nasa.gov and http://www.nasa.gov/cassini . The Cassini imaging team homepage is at http://ciclops.org and ESA website: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Image, Text, Credits: NASA/Tony Greicius/JPL-Caltech/Space Science Institute.

Best regards, Orbiter.ch

Lunar, Martian Greenhouses Designed to Mimic Those on Earth

NASA - Kennedy Space Center patch.

April 24, 2017

While astronauts have successfully grown plants and vegetables aboard the International Space Station, NASA scientists at the Kennedy Space Center in Florida are collaborating with a university team to develop long-term methods that could help sustain pioneers working in deep space.

Agency researchers believe while there are many challenges for human exploration beyond Earth, they are convinced there are solutions. According to Dr. Ray Wheeler, lead scientist in Kennedy Advanced Life Support Research, the Prototype Lunar/Mars Greenhouse project will support ongoing research in space to grow vegetables for food and cultivating plants to sustain life support systems.

Image above: Through the design and construction of an innovative hydroponic plant growth chamber, the Prototype Lunar Greenhouse is designed to sustain a continuous vegetarian diet for astronauts on distant locations such as the moon or Mars. It employs plants and crop production designed to provide not only food, but air revitalization, water recycling and waste recycling. Image Credit: University of Arizona.

"We're working with a team of scientists, engineers and small businesses at the University of Arizona to develop a closed-loop system," he said. "The approach uses plants to scrub carbon dioxide, while providing food and oxygen."

The prototype involves an inflatable, deployable greenhouse to support plant and crop production for nutrition, air revitalization, water recycling and waste recycling. The process is called a bioregenerative life support system.

Wheeler noted astronauts exhale carbon dioxide, which is then introduced into the greenhouse, and the plants then generate oxygen through photosynthesis. The water cycle begins with water that is brought along or found at the lunar or Martian landing site. Water is oxygenated, given nutrient salts, and it continuously flows across the root zone of the plants and returned to the storage system.

Back on Earth at the University of Arizona in Tucson, tests involving the Prototype Lunar Greenhouse have included determining what plants, seeds or other materials should be taken along to make the system work on the moon or Mars.

Learning what to take and what to gather on site will be crucial for living on distant locations. Using available resources located or grown on site is a practice is called in-situ resource utilization, or ISRU.

NASA scientists and engineers are developing systems to harness resources such as water that should be available in certain areas of the lunar or Martian surface to support missions lasting for months or years.

Image above: At the University of Arizona's Controlled Environment Agriculture Center, an 18 foot long, 7 foot, 3 inch diameter lunar greenhouse chamber is equipped as a prototype bioregenerative life support system. Image Credit: University of Arizona.

"We're mimicking what the plants would have if they were on Earth and make use of these processes for life support," said Dr. Gene Giacomelli, director of the Controlled Environment Agriculture Center at the University of Arizona. "The entire system of the lunar greenhouse does represent, in a small way, the biological systems that are here on Earth."

A professor in the University of Arizona's Agricultural and Biosystems Engineering Department, Giacomelli explains the next big step is to use additional lunar greenhouse units for specialized testing to ensure the system being developed will adequately support a crew of astronauts working on the moon or Mars.

"We will develop computer models to simulate what we're doing to automatically control the environment and provide a constant level of oxygen," he said.

Additionally, Dr. Roberto Furfaro at the University of Arizona is the principal investigator for the current phase of the project. He is a professor in the Systems and Industrial Engineering Department within the College of Engineering.

The prototypes now being developed are cylindrical -- 18 feet long and more than 8 feet in diameter and were built by Sadler Machine Company, one of the project partners.

To protect from radiation in space, the greenhouse units would likely be buried under surface soil or regolith thus requiring specialized lighting.

"We've been successful in using electric LED (light emitting diode) lighting to grow plants," Wheeler said. "We also have tested hybrids using both natural and artificial lighting."

Solar light could be captured with light concentrators that track the sun and then convey the light to the chamber using fiber optic bundles.

While studies in working on the surface of other locations in the solar system take place on Earth, aboard the space station astronauts have been gaining experience in growing crops in space.

Image above: Aboard the International Space Station, astronauts have been gaining experience in growing crops in space. Expedition 50 commander Shane Kimbrough of NASA harvests lettuce from the Veggie experiment on Dec. 2, 2016. The Veggie Plant Growth System is a deployable plant growth unit capable of producing salad-type crops to provide the crew with a palatable, nutritious and safe source of fresh food. Image Credit: NASA.

NASA’s Veggie Plant Growth System was the first American-built, fresh-food growth experiment on the station. It helped continue research for the development of food production systems for long-duration exploration missions. This work is part of Kennedy's efforts in plant research and production of food for exploration missions as directed by Human Research Project and the Space Life Physical Science Division.

From Earth, Wheeler sees the greenhouse system as a way to take some native processes for sustaining life during exploration beyond Earth.

"I think it's interesting to consider that we're taking our terrestrial companions with us," he said. "While there may be ways to engineer around it in terms of stowage and resupply, it wouldn't be as sustainable. The greenhouses provide a more autonomous approach to long-term exploration on the moon, Mars and beyond."

Related links:

Prototype Lunar/Mars Greenhouse: https://www.ag.arizona.edu/lunargreenhouse/

in-situ resource utilization (ISRU): http://www.nasa.gov/feature/nasas-exploration-plans-include-living-off-the-land

Veggie Plant Growth System:
http://orbiterchspacenews.blogspot.ch/2014/05/sciences-on-international-space-station.html

Journey to Mars: https://www.nasa.gov/topics/journeytomars/index.html

Living in Space: https://www.nasa.gov/topics/technology/living-in-space/index.html

Kennedy Space Center: https://www.nasa.gov/centers/kennedy/home/index.html

Images (mentioned), Text, Credits: NASA's Kennedy Space Center, by Bob Granath.

Best regards, Orbiter.ch