Satellites

NASA Hosts Media Call on Draft Solicitation for New Class of Launch Services 

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May 07, 2015
NASA Media Advisory M15-073

 

M-Cubed/COVE-2 is the reflightof a 1U CubeSat developed by U. Michigan to image the Earth at mid-resolution, approximately 200m per pixel, carrying the JPL developed COVE technology validation experiment.

Credits: NASA/JPL

NASA’s Launch Services Program has issued a draft Request for Proposal (RFP) for a new Venture Class Launch Services (VCLS), which would be commercial launch services for small satellites and experiments on science missions using a smaller than currently available class of rockets.

NASA will host a media teleconference at 1 p.m. EDT Monday, May 11 to discuss this strategic initiative, the RFP and the expectation for this class of launch services.

At present, launch opportunities for small satellites — often called CubeSats or nanosatellites — and small science missions are mostly limited to ride-share type arrangements, flying only when space is available on NASA and other launches. The Launch Services Program seeks to develop alternatives to this approach and help foster other launch services dedicated to transporting smaller payloads into orbit. The services acquired through such a contract will constitute the smallest class of launch services used by NASA.

Participants in the media briefing are:

  • Mark Wiese, chief, Flight Projects Branch, Launch Services Program Business Office, NASA’s Kennedy Space Center 
  • Garrett Skrobot, mission manager, Educational Launch of Nanosatellites (ELaNa), Launch Services Program, NASA’s Kennedy Space Center

This solicitation, and resulting contract or contracts, is intended to demonstrate a dedicated launch capability for smaller payloads that NASA anticipates it will require on a recurring basis for future science and CubeSat missions. CubeSats already are used in markets, such as imagery collection and analysis. In the future, CubeSat capabilities will include abilities, such as ship and aircraft tracking, improved weather prediction, and broader Internet coverage.

NASA intends to award one or more firm fixed-price VCLS contracts to accommodate 132 pounds (60 kilograms) of CubeSats a single launch or two launches carrying 66 pounds (30 kilograms) each. The launch provider will determine the launch location and date, but the launch must occur by April 15, 2018.

The public may watch or listen to the conference on either the phone or on NASA’s newsaudio website. Members of the media have received other information in order to participate, which has been excluded from this release.

However, the public is allowed to listen to the conference. To listen to teleconference, call 321-867-1220321-867-1240 or 321-867-1260 (usually reserved for members of the media), or the public and media members without proper credentials may listen online at: http://www.nasa.gov/newsaudio

For businessness interested in bidding process, the draft RFP is open for written questions and comments from industry entities until Wednesday, May 20. The final RFP, if issued, is anticipated to be released in June. The draft RFP may be accessed at: http://go.nasa.gov/1KMTeDR

For more information about NASA’s CubeSat Launch Initiative, visit: http://www.nasa.gov/directorates/heo/home/CubeSats_initiative.html

NASA’s Launch Services Program is focused on assuring the availability of long-term launch services for NASA while also promoting the continued evolution of the U.S. commercial space launch market. The capability anticipated to meet the requirement for a smaller launch vehicle represents an emerging category of launch services. 

For more information about NASA’s Launch Services Program, visit: http://www.nasa.gov/centers/kennedy/launchingrockets/index.html



Traffic Around Mars Gets Busy

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This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet’s two natural satellites. It illustrates the potential for intersections of the spacecraft orbits. Image Credit: NASA/JPL-Caltech



Fast Facts:

  • Five active spacecraft are orbiting Mars, an increase of two since last summer
  • An enhanced system warns if two orbiters may approach each other too closely

NASA has beefed up a process of traffic monitoring, communication and maneuver planning to ensure that Mars orbiters do not approach each other too closely. 

Last year’s addition of two new spacecraft orbiting Mars brought the census of active Mars orbiters to five, the most ever. NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) and India’s Mars Orbiter Mission joined the 2003 Mars Express from ESA (the European Space Agency) and two from NASA: the 2001 Mars Odyssey and the 2006 Mars Reconnaissance Orbiter (MRO). The newly enhanced collision-avoidance process also tracks the approximate location of NASA’s Mars Global Surveyor, a 1997 orbiter that is no longer working.

It’s not just the total number that matters, but also the types of orbits missions use for achieving their science goals. MAVEN, which reached Mars on Sept. 21, 2014, studies the upper atmosphere. It flies an elongated orbit, sometimes farther from Mars than NASA’s other orbiters and sometimes closer to Mars, so it crosses altitudes occupied by those orbiters. For safety, NASA also monitors positions of ESA’s and India’s orbiters, which both fly elongated orbits.

“Previously, collision avoidance was coordinated between the Odyssey and MRO navigation teams,” said Robert Shotwell, Mars Program chief engineer at NASA’s Jet Propulsion Laboratory, Pasadena, California. “There was less of a possibility of an issue. MAVEN’s highly elliptical orbit, crossing the altitudes of other orbits, changes the probability that someone will need to do a collision-avoidance maneuver. We track all the orbiters much more closely now. There’s still a low probability of needing a maneuver, but it’s something we need to manage.”

Traffic management at Mars is much less complex than in Earth orbit, where more than 1,000 active orbiters plus additional pieces of inactive hardware add to hazards. As Mars exploration intensifies, though, and will continue to do so with future missions, precautions are increasing. The new process was established to manage this growth as new members are added to the Mars orbital community in years to come.

All five active Mars orbiters use the communication and tracking services of NASA’s Deep Space Network, which is managed at JPL. This brings trajectory information together, and engineers can run computer projections of future trajectories out to a few weeks ahead for comparisons.

“It’s a monitoring function to anticipate when traffic will get heavy,” said Joseph Guinn, manager of JPL’s Mission Design and Navigation Section. “When two spacecraft are predicted to come too close to one another, we give people a heads-up in advance so the project teams can start coordinating about whether any maneuvers are needed.”

The amount of uncertainty in the predicted location of a Mars orbiter a few days ahead is more than a mile (more than two kilometers). Calculating projections for weeks ahead multiplies the uncertainty to dozens of miles, or kilometers. In most cases when a collision cannot be ruled out from projections two weeks ahead, improved precision in the forecasting as the date gets closer will rule out a collision with no need for avoidance action. Mission teams for the relevant orbiters are notified in advance when projections indicate a collision is possible, even if the possibility will likely disappear in subsequent projections. This situation occurred on New Year’s weekend, 2015.

On Jan. 3, automated monitoring determined that two weeks later, MAVEN and MRO could come within about two miles (three kilometers) of each other, with large uncertainties remaining in the exact passing distance. Although that was a Saturday, automatic messages went out to the teams operating the orbiters.

“In this case, before the timeline got short enough to need to plan an avoidance maneuver, the uncertainties shrank, and that ruled out the chance of the two spacecraft coming too near each other,” Guinn said. This is expected to be the usual pattern, with the advance warning kicking off higher-level monitoring and initial discussions about options.

If preparations for an avoidance maneuver were called for, spacecraft commands would be written, tested and approved for readiness, but such commands would not be sent to a spacecraft unless projections a day or two ahead showed probability of a hazardous conjunction. The amount of uncertainty about each spacecraft’s exact location varies, so the proximity considered unsafe also varies. For some situations, a day-ahead projection of two craft coming within about 100 yards (100 meters) of each other could trigger a maneuver.

The new formal collision-avoidance process for Mars is part of NASA’s Multi-Mission Automated Deep-Space Conjunction Assessment Process. A side benefit of it is that information about when two orbiters will be near each other — though safely apart — could be used for planning coordinated science observations. The pair could look at some part of Mars or its atmosphere from essentially the same point of view simultaneously with complementary instruments.

Odyssey, MRO and MAVEN — together with NASA’s two active Mars rovers, Opportunity and Spirit — are part of NASA’s robotic exploration of Mars that is preparing the way for human-crewed missions there in the 2030s and later, in NASA’s Journey to Mars strategy.

NASA’s Goddard Space Flight Center manages the MAVEN project for the NASA Science Mission Directorate, Washington. MAVEN’s principal investigator is based at the University of Colorado’s Laboratory for Atmospheric and Space Physics. JPL, a division of the California Institute of Technology in Pasadena, manages NASA’s Mars Exploration Program and the Odyssey and MRO projects for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built all three NASA Mars orbiters.

For more about NASA’s Mars Exploration Program, visit:  http://mars.jpl.nasa.gov or http://www.nasa.gov/mars.

 

NASA Aids Response to Nepal Quake

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NASA data and expertise are providing valuable information for the ongoing response to the April 25, 2015, magnitude 7.8 Gorkha earthquake in Nepal. The quake has caused significant regional damage and a humanitarian crisis. Credit: NASA/JPL/Ionosphere Natural Hazards Team



NASA and its partners are gathering the best available science and information on the April 25, 2015, magnitude 7.8 earthquake in Nepal, referred to as the Gorkha earthquake, to assist in relief and humanitarian operations. Organizations using these NASA data products and analyses include the U.S. Geological Survey, United States Agency for International Development (USAID)/Office of U.S. Foreign Disaster Assistance, World Bank, American Red Cross, and the United Nations Children’s Fund. 

NASA and its collaborators are pulling optical and radar satellite data from international and domestic partners and compiling them into a variety of products. The products include “vulnerability maps,” used to determine risks that may be present; and “damage proxy maps,” used to determine the type and extent of existing damage. Such products can be used to better direct response efforts.

The satellite data will be used to compile maps of ground surface deformation and to create risk models. NASA and its partners are also contributing to assessments of damage to infrastructure. They are tracking remote areas that may be a challenge for relief workers to reach, as well as areas that could be at risk for landslides, river damming, floods and avalanches. The data will contribute to ongoing investigations of our restless Earth and its impacts on society.

NASA is helping get satellite data into the hands of government officials in Nepal where Internet bandwidth is limited. The joint NASA-USAID SERVIR project is supporting disaster response mapping efforts through the SERVIR-Himalaya office at the International Centre for Integrated Mountain Development in Kathmandu. SERVIR staff at NASA’s Marshall Space Flight Center, Huntsville, Alabama, are coordinating image tasking, processing, compression, and distribution efforts with colleagues from Goddard Space Flight Center in Greenbelt, Maryland, and the Jet Propulsion Laboratory in Pasadena, California.

NASA technology that can locate people trapped beneath collapsed buildings is being deployed to Nepal. A remote-sensing radar technology called FINDER (Finding Individuals for Disaster and Emergency Response), developed by JPL in conjunction with the U.S. Department of Homeland Security’s Science and Technology Directorate, can locate individuals buried as deep as 30 feet (9.1 meters) in crushed materials, hidden behind 20 feet (6 meters) of solid concrete, and from a distance of 100 feet (30.5 meters) in open spaces. This technology, licensed by the private entity R4 Incorporated of Edgewood, Maryland, has been taken to Nepal to assist with recovery efforts.

NASA uses the vantage point of space to increase our understanding of our home planet, improve lives and safeguard our future. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records. The agency freely shares this unique knowledge and works with institutions around the world to gain new in-sights into how our planet is changing. 

Data and images will be released as they become available at:

http://www.nasa.gov/content/images-of-the-april-2015-nepal-earthquake

 

Components of Beagle 2 Flight System on Mars

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PRESS RELEASE (JPL) – The Beagle 2 Mars Lander, built by the United Kingdom, has been thought lost on Mars since 2003, but has now been found in images from NASA’s Mars Reconnaissance Orbiter.

Beagle 2 was released by the European Space Agency’s Mars Express orbiter but never heard from after its expected landing. Images from the High Resolution Imaging Science Experiment (HiRISE) camera on Mars Reconnaissance Orbiter have been interpreted as showing the Beagle 2 did make a soft landing and at least partially deployed its solar panels.

A set of three observations with the orbiter’s High Resolution Imaging Science Experiment (HiRISE) camera shows Beagle 2 partially deployed on the surface of the planet, ending the mystery of what happened to the mission more than a decade ago. They show that the lander survived its Dec. 25, 2003, touchdown enough to at least partially deploy its solar arrays.

“I am delighted that Beagle 2 has finally been found on Mars,” said Mark Sims of the University of Leicester, U.K. He was an integral part of the Beagle 2 project from the start, leading the initial study phase and was Beagle 2 mission manager. “Every Christmas Day since 2003 I have wondered what happened to Beagle 2. My Christmas Day in 2003 alongside many others who worked on Beagle 2 was ruined by the disappointment of not receiving data from the surface of Mars. To be frank I had all but given up hope of ever knowing what happened to Beagle 2. The images show that we came so close to achieving the goal of science on Mars.

HiRISE images initially searched by Michael Croon of Trier, Germany, a former member of the European Space Agency’s Mars Express operations team, provide evidence for the lander and key descent components on the surface of Mars within the expected landing area of Isidis Planitia, an impact basin close to the equator.

Subsequent re-imaging and analysis by the Beagle 2 team, the HiRISE team and NASA’s Jet Propulsion Laboratory, Pasadena, California, have confirmed that the targets discovered are of the correct size, shape, color and dispersion to be Beagle 2. JPL planetary geologist Tim Parker, who has assisted in the search and processed some of the images said, “I’ve been looking over the objects in the images carefully, and I’m convinced that these are Beagle 2 hardware.”

Analysis of the images indicates what appears to be a partially deployed configuration, with what is thought to be the rear cover with its pilot/drogue chute (still attached) and main parachute close by. Due to the small size of Beagle 2 (less than 7 feet, or 2 meters across for the deployed lander) it is right at the limit of detection of HiRISE, the highest-resolution camera orbiting Mars. The targets are within the expected landing area at a distance of about three miles (five kilometers) from its center.

“I can imagine the sense of closure that the Beagle 2 team must feel,” said Richard Zurek of JPL, project scientist now for Mars Reconnaissance Orbiter (MRO) and previously for NASA’s still-missing 1998 Mars Polar Lander. “MRO has helped find safe landing sites on Mars for the Curiosity and Phoenix missions and has searched for missing craft to learn what may have gone wrong. It’s an extremely difficult task, as the craft are small and the search areas are vast. It takes the best camera we have in Mars orbit and work by dedicated individuals to be successful at this.”

HiRISE is operated by the University of Arizona, Tucson. The instrument was built by Ball Aerospace & Technologies Corp. of Boulder, Colorado. The Mars Reconnaissance Orbiter Project is managed for NASA’s Science Mission Directorate in Washington, by JPL, a division of the California Institute of Technology, Pasadena.

View all images (color) on JPL site

For more information about HiRISE

Additional information about MRO

Media Contact

Guy Webster
Jet Propulsion Laboratory, Pasadena, California
818-354-6278
guy.webster@jpl.nasa.gov

Technology Innovations Spin NASA’s SMAP into Space

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It’s active. It’s passive. And it’s got a big, spinning lasso.

Scheduled for launch on Jan. 29, 2015, NASA’s Soil Moisture Active Passive (SMAP) instrument will measure the moisture lodged in Earth’s soils with an unprecedented accuracy and resolution. The instrument’s three main parts are a radar, a radiometer and the largest rotating mesh antenna ever deployed in space.

Remote sensing instruments are called “active” when they emit their own signals and “passive” when they record signals that already exist. The mission’s science instrument ropes together a sensor of each type to corral the highest-resolution, most accurate measurements ever made of soil moisture — a tiny fraction of Earth’s water that has a disproportionately large effect on weather and agriculture.

To enable the mission to meet its accuracy needs while covering the globe every three days or less, SMAP engineers at NASA’s Jet Propulsion Laboratory in Pasadena, California, designed and built the largest rotating antenna that could be stowed into a space of only one foot by four feet (30 by 120 centimeters) for launch. The dish is 19.7 feet (6 meters) in diameter.

“We call it the spinning lasso,” said Wendy Edelstein of NASA’s Jet Propulsion Laboratory, Pasadena, California, the SMAP instrument manager.

Like the cowboy’s lariat, the antenna is attached on one side to an arm with a crook in its elbow. It spins around the arm at about 14 revolutions per minute (one complete rotation every four seconds). The antenna dish was provided by Northrop Grumman Astro Aerospace in Carpinteria, California. The motor that spins the antenna was provided by the Boeing Company in El Segundo, California.

“The antenna caused us a lot of angst, no doubt about it,” Edelstein noted. Although the antenna must fit during launch into a space not much bigger than a tall kitchen trash can, it must unfold so precisely that the surface shape of the mesh is accurate within about an eighth of an inch (a few millimeters).

The mesh dish is edged with a ring of lightweight graphite supports that stretch apart like a baby gate when a single cable is pulled, drawing the mesh outward. “Making sure we don’t have snags, that the mesh doesn’t hang up on the supports and tear when it’s deploying — all of that requires very careful engineering,” Edelstein said. “We test, and we test, and we test some more. We have a very stable and robust system now.”

SMAP’s radar, developed and built at JPL, uses the antenna to transmit microwaves toward Earth and receive the signals that bounce back, called backscatter. The microwaves penetrate a few inches or more into the soil before they rebound. Changes in the electrical properties of the returning microwaves indicate changes in soil moisture, and also tell whether or not the soil is frozen. Using a complex technique called synthetic aperture radar processing, the radar can produce ultra-sharp images with a resolution of about half a mile to a mile and a half (one to three kilometers).

SMAP’s radiometer detects differences in Earth’s natural emissions of microwaves that are caused by water in soil. To address a problem that has seriously hampered earlier missions using this kind of instrument to study soil moisture, the radiometer designers at NASA’s Goddard Space Flight Center, Greenbelt, Maryland, developed and built one of the most sophisticated signal-processing systems ever created for such a scientific instrument.

The problem is radio frequency interference. The microwave wavelengths that SMAP uses are officially reserved for scientific use, but signals at nearby wavelengths that are used for air traffic control, cell phones and other purposes spill over into SMAP’s wavelengths unpredictably. Conventional signal processing averages data over a long time period, which means that even a short burst of interference skews the record for that whole period. The Goddard engineers devised a new way to delete only the small segments of actual interference, leaving much more of the observations untouched.

Combining the radar and radiometer signals allows scientists to take advantage of the strengths of both technologies while working around their weaknesses. “The radiometer provides more accurate soil moisture but a coarse resolution of about 40 kilometers [25 miles] across,” said JPL’s Eni Njoku, a research scientist with SMAP. “With the radar, you can create very high resolution, but it’s less accurate. To get both an accurate and a high-resolution measurement, we process the two signals together.”

SMAP will be the fifth NASA Earth science mission launched within the last 12 months.

For more about the SMAP mission, visit:

http://www.nasa.gov/smap/

NASA monitors Earth’s vital signs from space, air and land with a fleet of satellites and ambitious airborne and ground-based observation campaigns. NASA develops new ways to observe and study Earth’s interconnected natural systems with long-term data records and computer analysis tools to better see how our planet is changing. The agency shares this unique knowledge with the global community and works with institutions in the United States and around the world that contribute to understanding and protecting our home planet.

For more information about NASA’s Earth science activities this year, visit:

http://www.nasa.gov/earthrightnow

Media Contact

Alan Buis
Jet Propulsion Laboratory, Pasadena, California
818-354-0474
Alan.Buis@jpl.nasa.gov

Written by Carol Rasmussen
NASA Earth Science News Team

2014-444

Dawn Spacecraft Begins Approach to Dwarf Planet Ceres

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• Dawn has entered its approach phase toward Ceres
• The spacecraft will arrive at Ceres on March 6, 2015

PRESS RELEASE (NASA/JPL) – NASA’s Dawn spacecraft has entered an approach phase in which it will continue to close in on Ceres, a Texas-sized dwarf planet never before visited by a spacecraft. Dawn launched in 2007 and is scheduled to enter Ceres orbit in March 2015.

Dawn recently emerged from solar conjunction, in which the spacecraft is on the opposite side of the sun, limiting communication with antennas on Earth. Now that Dawn can reliably communicate with Earth again, mission controllers have programmed the maneuvers necessary for the next stage of the rendezvous, which they label the Ceres approach phase. Dawn is currently 400,000 miles (640,000 kilometers) from Ceres, approaching it at around 450 miles per hour (725 kilometers per hour).

The spacecraft’s arrival at Ceres will mark the first time that a spacecraft has ever orbited two solar system targets. Dawn previously explored the protoplanet Vesta for 14 months, from 2011 to 2012, capturing detailed images and data about that body.

“Ceres is almost a complete mystery to us,” said Christopher Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles. “Ceres, unlike Vesta, has no meteorites linked to it to help reveal its secrets. All we can predict with confidence is that we will be surprised.”

The two planetary bodies are thought to be different in a few important ways. Ceres may have formed later than Vesta, and with a cooler interior. Current evidence suggests that Vesta only retained a small amount of water because it formed earlier, when radioactive material was more abundant, which would have produced more heat. Ceres, in contrast, has a thick ice mantle and may even have an ocean beneath its icy crust.

Ceres, with an average diameter of 590 miles (950 kilometers), is also the largest body in the asteroid belt, the strip of solar system real estate between Mars and Jupiter. By comparison, Vesta has an average diameter of 326 miles (525 kilometers), and is the second most massive body in the belt.

The spacecraft uses ion propulsion to traverse space far more efficiently than if it used chemical propulsion. In an ion propulsion engine, an electrical charge is applied to xenon gas, and charged metal grids accelerate the xenon particles out of the thruster. These particles push back on the thruster as they exit, creating a reaction force that propels the spacecraft. Dawn has now completed five years of accumulated thrust time, far more than any other spacecraft.

“Orbiting both Vesta and Ceres would be truly impossible with conventional propulsion. Thanks to ion propulsion, we’re about to make history as the first spaceship ever to orbit two unexplored alien worlds,” said Marc Rayman, Dawn’s chief engineer and mission director, based at NASA’s Jet Propulsion Laboratory in Pasadena, California.

The next couple of months promise continually improving views of Ceres, prior to Dawn’s arrival. By the end of January, the spacecraft’s images and other data will be the best ever taken of the dwarf planet.

The Dawn mission to Vesta and Ceres is managed by JPL, a division of the California Institute of Technology in Pasadena, for NASA’s Science Mission Directorate, Washington. UCLA is responsible for overall Dawn mission science.

More information about Dawn:

http://dawn.jpl.nasa.gov
Media Contact

Elizabeth Landau
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6425
Elizabeth.Landau@jpl.nasa.gov

2014-443

Rosetta comet probe team narrows landing site to five locations

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This annotated image depicts four of the five potential landing sites for the Rosetta mission's Philae lander.
This annotated image depicts four of the five potential landing sites for the Rosetta mission’s Philae lander (Courtesy NASA/JPL-Caltech, Image by ESA/Rosetta/MPS for OSIRIS Team).

The European Space Agency’s Rosetta Comet mission has chosen five likely landing sites for its Philae’s lander on comet 67P/Churyumov-Gerasimenko. The lander is scheduled to descend down to the comet’s nucleus in November.

According to a press release by NASA’s Jet Propulsion Laboratory:

Rosetta is an international mission headed up by the ESA with support from NASA, and will be the first ever attempt to land on a comet.

Rosetta is an international mission headed up by the ESA with support from NASA, including providing instruments.

 The European Space Agency’s Rosetta mission has chosen five candidate landing sites on comet 67P/Churyumov-Gerasimenko for its Philae lander. Philae’s descent to the comet’s nucleus, scheduled for this November, will be the first such landing ever attempted. Rosetta is an international mission spearheaded by the European Space Agency with support and instruments provided by NASA.
Picking the landing site is complex and a balancing the technical issues of the orbiter and lander during the entire phases of separation, descent, landing, and all operations on the surface must be precise.

Due to the distance from Earth and the orbiter and lander creates uncertainties in navigating the orbiter close to the comet, the only way possible to pick a landing site in terms of an ellipse, which will cover up to six-tenths of a square mile (or one square kilometer) where the Philae lander might land.

“This is the first time landing sites on a comet have been considered,” said Stephan Ulamec, Philae Lander Manager at the German Aerospace Center, Cologne, Germany in a press release.

“The candidate sites that we want to follow up for further analysis are thought to be technically feasible on the basis of a preliminary analysis of flight dynamics and other key issues – for example, they all provide at least six hours of daylight per comet rotation and offer some flat terrain. Of course, every site has the potential for unique scientific discoveries.”
 For each possible zone, important questions must be asked:

Will the lander be able to maintain regular communications with Rosetta?

 How common are surface hazards such as large boulders, deep crevasses or steep slopes?

Is there sufficient illumination for scientific operations and enough sunlight to recharge the lander’s batteries beyond its initial 64-hour lifetime without causing overheating?

The team reduced the number of landing sites from 10 to five, and gave them letters that have no special meanings.

 Three of the landing sites (B, I and J) are on the smaller lobe of the comet, where the other two sites (A and C) are located on the larger lobe.

“The process of selecting a landing site is extremely complex and dynamic; as we get closer to the comet, we will see more and more details, which will influence the final decision on where and when we can land,” said Fred Jansen, Rosetta’s mission manager from the European Space Agency’s Science and Technology Centre in Noordwijk, The Netherlands, in the same press release.

 “We had to complete our preliminary analysis on candidate sites very quickly after arriving at the comet, and now we have just a few more weeks to determine the primary site. The clock is ticking and we now have to meet the challenge to pick the best possible landing site.”
This image of comet 67P/Churyumov-Gerasimenko shows the diversity of surface structures on the comet...
This image of comet 67P/Churyumov-Gerasimenko shows the diversity of surface structures on the comet’s nucleus. It was taken by the Rosetta spacecraft’s navigation camera on August 7, 2014. At the time, the spacecraft was 65 miles (104 kilometers) away from the 2.5 mile (4 kilometer) wide nucleus. Courtesy NASA/JPL-Caltech, Image by ESA/Rosetta/MPS for OSIRIS Team MPS/UPD/LAM/IAA/SSO/INTA/UPM/DAS
 The next thing the team must do is to prepare a comprehensive analysis of each of the five landing sites so they can determine the best orbital and operational strategies that could be used so Rosetta can deliver the lander to any one of them.

During the time the team is preparing their analysis, Rosetta will move to 31 miles (50 kilometers) of the comet allowing more detailed study of the five landing sites.

 The Rosetta team will have the complete assessments of all five landing sites completed by September 14, and they will be ranked in order to select a primary landing site, with both a full detailed strategy for landing the orbiter at the primary or selected site, along with a backup contingency.

The ESA Rosetta team plans to land the Philae lander sometime around mid-November when the comet will be about 280 million miles (450 million Kilometers). This means the comet will be three times the distance than the Earth is to the Sun (280 million miles also equals 3 astronomical units, where an astronomical unit is 93 million miles, or the distance between the Sun and the Earth).

At 3 AU, there should be little to no activity on the comet that would jeopardize the landing of the Philae lander on the comet’s surface, and just before the comet becomes active.

Launched in March 2004, Rosetta was reactivated in January 2014 after a record 957 days in hibernation. Composed of an orbiter and lander, Rosetta’s objectives since arriving at comet 67P/Churyumov-Gerasimenko earlier this month are to study the celestial object up close in unprecedented detail, prepare for landing a probe on the comet’s nucleus in November, and track its changes through 2015, as it sweeps past the sun.

Illustration of comet-seeker Rosetta with details of its progress
Illustration of comet-seeker Rosetta with details of its progress (AFP/File – P. Pizarro/A. Bommenel/K. Tian)
 Rosetta’s objectives as the spacecraft reached comet 67P/Churyumov-Gerasimenko earlier this month is to do a close up study of the comet in unprecedented detail and to prepare for landing the probe on the comet’s nucleus and track any changes through 2015 as it orbits comet 67P/Churyumov-Gerasimenko.

Cosmologists consider comets as time capsules containing materials left over from building of the Solar System 3.4 billion years ago. Rosetta’s lander will obtain the very first images taken from a comet’s primordial composition by drilling into the surface.

 Scientists will also be able to study how a comet changes its composition as it makes its way around the Sun. It is believed this will help scientists to understand more about the role of comets may have played in seeding the Earth with water, and even life. They will also be able to learn more about the evolution of our Solar System.

According to the press release:

 The scientific imaging system, OSIRIS, was built by a consortium led by the Max Planck Institute for Solar System Research (Germany) in collaboration with Center of Studies and Activities for Space, University of Padua (Italy), the Astrophysical Laboratory of Marseille (France), the Institute of Astrophysics of Andalusia, CSIC (Spain), the Scientific Support Office of the European Space Agency (Netherlands), the National Institute for Aerospace Technology (Spain), the Technical University of Madrid (Spain), the Department of Physics and Astronomy of Uppsala University (Sweden) and the Institute of Computer and Network Engineering of the TU Braunschweig (Germany). OSIRIS was financially supported by the national funding agencies of Germany (DLR), France (CNES), Italy (ASI), Spain, and Sweden and the ESA Technical Directorate.

Rosetta is an ESA mission with contributions from its member states and NASA. Rosetta’s Philae lander is provided by a consortium led by the German Aerospace Center, Cologne; Max Planck Institute for Solar System Research, Gottingen; French National Space Agency, Paris; and the Italian Space Agency, Rome. NASA’s Jet Propulsion Laboratory in Pasadena, California, a division of the California Institute of Technology, manages the U.S. participation in the Rosetta mission for NASA’s Science Mission Directorate in Washington.

For Specifications on: 67P/Churyumov-Gerasimenko