samedi 9 septembre 2017

NASA Sees Hurricane Irma's Eye Along Cuba's Coast














NASA - EOS Aqua Mission logo / NOAA & NASA - GOES Mission logo.

Sept. 9, 2017

Irma (Atlantic Ocean)

Hurricane Irma was moving up Cuba's northern coast when NASA's Aqua satellite passed overhead.  A satellite instrument revealed coldest temperatures of powerful thunderstorm tops surrounding Irma's eye and in a band of thunderstorms over the Florida Keys.


Image above: This infrared image from the MODIS instrument aboard NASA's Aqua satellite shows extremely cold temperatures (red) in thunderstorms surrounding the eye of Hurricane Irma as it traveled along Cuba's northern coast on Sept. 9 at 3:15 a.m. EDT (07:15 UTC). Image Credits: NASA/NRL.

Infrared MODIS data showed two areas with very cold cloud top temperatures of strong thunderstorms. They were around center of circulation and in a band of thunderstorms north of the center, where temperatures were as cold as minus 80 degrees Fahrenheit (minus 62.2 Celsius). Temperatures that cold indicate strong uplift in the storm and cloud tops high into the troposphere. NASA research has shown that storms with cloud tops that cold have the ability to generate heavy rain.


Image above: This visible image of Category 4 Hurricane Irma was taken on Saturday, September 9, 2017 at 10:37 a.m. EDT (1437 UTC) by the NOAA GOES East satellite. Image Credits: NASA/NOAA GOES Project.

Warnings and Watches

At 11 a.m. EDT the National Hurricane Center noted many warnings and watches in effect.

A Storm Surge Warning is in effect for Volusia/Brevard County line southward around the Florida peninsula to the Suwanee River, the Florida Keys and Tampa Bay.  A Storm Surge Watch is in effect from north of the Volusia/Brevard County line to the Isle of Palms, South Carolina, and north of the Suwanee River to Ochlockonee River.

Satellite Animation Sees Category 4 Hurricanes Irma and Jose, Katia Landfall

Video above: This animation of NOAA's GOES East satellite imagery from Sept. 6 at 9:45 a.m. EDT (1345 UTC) to Sept. 9 ending at 10:15 a.m. EDT (1415 UTC) shows Category 4 Hurricane Irma approaching south Florida and Category 4 Hurricane Jose approach the northern Leeward Islands. Meanwhile, Hurricane Storm Katia made landfall and dissipated in eastern Mexico. TRT: 00:36. Image Credits: NASA-NOAA GOES Project.

A Hurricane Warning is in effect for Fernandina Beach southward around the Florida peninsula to the Aucilla River,  the Florida Keys, Lake Okeechobee, Florida Bay. A Hurricane Warning is also in effect for the Cuban provinces of Camaguey, Ciego de Avila, Sancti Spiritus, Villa Clara, Matanzas, and Havana,  Andros Island, Bimini and Grand Bahama. A Hurricane Watch is in effect from north of Fernandina Beach to Edisto Beach, west of the Aucilla River to Indian Pass, Florida. A Hurricane Watch is also in effect for the Cuban provinces of Holguin and Las Tunas.

A Tropical Storm Warning is in effect for Cuban provinces of Holguin, Las Tunas, and a Tropical Storm Watch is in effect from north of Edisto Beach to South Santee River and west of Indian Pass to the Okaloosa/Walton County Line.

Hurricane Irma at 11 a.m. EDT on Saturday, September 9, 2017

At 11 a.m. EDT (1500 UTC), the eye of Hurricane Irma was located by a reconnaissance plane and radar near latitude 22.8 North, longitude 79.8 West. Irma is moving toward the west along the north coast of Cuba at near 9 mph (15 km/h).  A northwest motion is expected to begin later today with a turn toward the north-northwest on Sunday.

Maximum sustained winds are near 125 mph (205 km/h) with higher gusts.  Irma is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale.  Irma is forecast to re-strengthen once it moves away from Cuba, and Irma is expected to remain a powerful hurricane as it approaches Florida. Hurricane-force winds extend outward up to 70 miles (110 km) from the center and tropical-storm-force winds extend outward up to 195 miles (315 km). The minimum central pressure reported by an Air Force plane was 941 millibars.

On the forecast track, the core of Irma will continue to move near or over the north coast of Cuba later today, and will reach the Florida Keys Sunday morning.  The hurricane is expected to move along or near the southwest coast of Florida Sunday afternoon.

For updates on Irma and effects of wind, storm surge and rainfall, visit the National Hurricane Center website: http://www.nhc.noaa.gov/

Aqua Satellite: https://www.nasa.gov/mission_pages/aqua/index.html

GOES (Geostationary Environmental Operational Satellites): http://www.nasa.gov/goes/

Images (mentioned), Video (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

vendredi 8 septembre 2017

NASA's Fleet of Satellites Covering Powerful Hurricane Irma














NOAA & NASA - GOES Mission logo / NASA - EOS Aqua Mission logo / NASA - Suomi NPP Mission logo.

Sep. 08, 2017

Irma (Atlantic Ocean)

NASA's fleet of satellites have been continually providing forecasters with data on Hurricane Irma. NASA-NOAA's Suomi NPP satellite provided a look at the wide-eye of Irma and if you think about the area of maximum sustained winds around the eye, it's similar to a wide F2 tornado. 


Image above: NASA's Aqua satellite captured infrared temperature data on Hurricane Irma on Sept. 8 at 2:29 a.m. EDT (0629 UTC). The image showed very cold cloud top temperatures colder than minus 63 degrees Fahrenheit (minus 53 degrees Celsius) in the storm, stretching over Hispaniola, eastern Cuba and the Bahamas. Image Credits: NASA JPL/Ed Olsen.

The Atmospheric Infrared Sounder or AIRS instrument aboard NASA's Aqua satellite captured infrared temperature data on Hurricane Irma on Sept. 8 at 2:29 a.m. EDT (0629 UTC). The image showed very cold cloud top temperatures colder than minus 63 degrees Fahrenheit (minus 53 degrees Celsius) in the storm, stretching over Hispaniola, eastern Cuba and the Bahamas. NASA research has shown that cloud tops that cold are high in the troposphere and have the potential to generate heavy rainfall.

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard NASA-NOAA's Suomi NPP satellite provided an infrared look at the thunderstorms throughout Irma on Sept. 9 at 2:39 a.m. EDT. The VIIRS image showed the well-defined eye of Irma with strong thunderstorms around the eye which is indicative of an intense tropical system. Strongest thunderstorms with coldest cloud tops were as cold as 195 Kelvin (minus 78.1 degrees Celsius/minus 108.7 degrees Fahrenheit).


Image above: In this Suomi NPP satellite infrared image from Sept. 9 at 2:39 a.m. EDT, the well-defined eye of Irma is visible with convection around the eye which is indicative of an intense tropical system. Strongest thunderstorms with coldest cloud tops (black) were as cold as 195 Kelvin. Image Credits: NASA/NOAA/UWM-CIMSS, William Straka.

NOAA's GOES East satellite captured an infrared image of Hurricane Irma in the Bahamas at 4:45 a.m. EDT that showed a clear eye and a symmetrical, powerful Category 4 hurricane. NOAA manages the GOES series of satellites and the NASA/NOAA GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Maryland produces images and animations from that data.


Image above: NOAA's GOES East satellite captured this infrared image of Hurricane Irma in the Bahamas at 4:45 a.m. EDT. Image Credits: NASA/NOAA GOES Project.

NASA uses a constellation of domestic and international satellites to better understand the rainfall accumulations of Irma, wind speeds, and impacts as the storm makes landfall.  

Irma's Area of Maximum Sustained Winds Like a Wide Tornado

The National Hurricane Center (NHC) noted that hurricane-force winds extend outward up to 70 miles (110 km) from the center and tropical-storm-force winds extend outward up to 185 miles (295 km). Maximum sustained winds are near 150 mph (240 kph) with higher gusts.

Scott Braun, research meteorologist at NASA Goddard said that "Hurricane force winds mean greater than 64 knots and tropical storm force winds are greater than 34 knots. The actual diameter of hurricane force winds is 120 miles. However, that is just for greater than 64 knots. The area with greater than 150 mph wind will be smaller." 

The area of maximum sustained winds near 150 mph fluctuate but on average have been about 25 miles out from the eye. Using that as average, if you think of the power of these rotating winds compared to a tornado, it would be would be similar to a 50-mile wide F2 tornado on the Fujita Scale (with maximum winds between 113 and 157 mph).

Warnings and Watches on Sept. 9

At 11 a.m. EDT on Sept. 9, the National Hurricane Center (NHC) had a Storm Surge Warning is in effect for Sebastian Inlet southward around the Florida peninsula to Venice, Florida, and the Florida Keys. A Storm Surge Watch is in effect from North of Sebastian Inlet to Ponce Inlet.

A Hurricane Warning is in effect for Jupiter Inlet southward around the Florida peninsula to Bonita Beach, Florida; the Florida Keys; Lake Okeechobee; Florida Bay; the Southeastern Bahamas and the Turks and Caicos Islands; the Cuban provinces of Camaguey, Ciego de Avila, Sancti Spiritus, and Villa Clara; the Central Bahamas and the Northwestern Bahamas.

A Hurricane Watch is in effect from north of Jupiter Inlet to the Flagler/Volusia County Line; north of Bonita Beach to Anclote River and the Cuban provinces of Guantanamo, Holguin, Las Tunas and Matanzas. A Tropical Storm Warning is in effect for the Cuban provinces of Guantanamo, Holguin, and Las Tunas.

Irma's Location at 11 a.m. EDT on Sept. 8

At 11 a.m. EDT (1500 UTC), the NHC said the distinct eye of Hurricane Irma was located near 22.0 degrees north latitude and 75.3 degrees west longitude. That's 405 miles (655 km) southeast of Miami, Florida.

Irma was moving toward the west-northwest near 14 mph (22 kph), and this motion is expected to continue for the next day or so with a decrease in forward speed.  A turn toward the northwest is expected by late Saturday, Sept. 9. Maximum sustained winds are near 150 mph (240 kph) with higher gusts. Irma is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.  Some fluctuations in intensity are likely during the next day or two, but Irma is forecast to remain a powerful category 4 hurricane as it approaches Florida.

Hurricane-force winds extend outward up to 70 miles (110 km) from the center and tropical-storm-force winds extend outward up to 185 miles (295 km). The latest minimum central pressure reported by both Air Force and NOAA Hurricane Hunter planes was 927 millibars.

Key Cautions to Remember

NHC noted several key cautions to keep in mind:

1. Irma is an extremely dangerous Category 4 hurricane and will continue to bring life-threatening wind, storm surge, and rainfall hazards to the Bahamas through Saturday.

2. Irma is likely to make landfall in Florida as a dangerous major hurricane, and will bring life-threatening wind impacts to much of the state regardless of the exact track of the center.

3. There is the danger of life-threatening storm surge inundation in southern Florida and the Florida Keys during the next 36 hours, where a Storm Surge Warning is in effect.

4. Irma is expected to produce very heavy rain and inland flooding. Total rain accumulations of 4 to 12 inches, with isolated amounts of 20 inches are expected over the Florida peninsula Saturday through Monday.

On the NHC forecast track, the eye of Irma should move near the north coast of Cuba and the central Bahamas today and Saturday, and be near the Florida Keys and the southern Florida Peninsula Sunday morning, Sept. 10.

For updates on Irma visit: http://www.nhc.noaa.gov/

Aqua Satellite: https://www.nasa.gov/mission_pages/aqua/index.html

GOES (Geostationary Environmental Operational Satellites): http://www.nasa.gov/goes/

Suomi NPP (National Polar-orbiting Partnership): http://www.nasa.gov/mission_pages/NPP/main/index.html

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

ISS Pass Over Hurricane Jose and Hurricane Irma












ISS - International Space Station patch.

Sept. 8, 2017


Image above: Flying over hurricane Jose, Atlantic Ocean, altitude: 404,46 Km / speed: 27'651 Km/h. Image captured by Roland Berga with EarthCam from ISS - International Space Station (via ISS HD Live application) on September 8, 2017 at 16:12 UTC.

ISS Pass Over Hurricane Jose and Hurricane Irma 9/8/17

Video above: The International Space Station passed over two major Atlantic hurricanes on Friday, Sept. 8. First, the station flew approximately 250 miles over Hurricane Jose at approximately 10:10 a.m. EDT while the Category 3 storm was in the Atlantic just east of the Caribbean. One orbit of the Earth later, the station flew over Hurricane Irma at approximately 11:40 a.m. EDT. The powerful Category 4 storm had already brought destructive wind and rain to islands across the Caribbean and is forecast to impact the Florida peninsula. Video Credit: NASA.


Image above: Flying over hurricane Irma, between Cuba and Florida, altitude: 406,72 Km / speed: 27'665 Km/h. Image captured by Roland Berga with EarthCam from ISS - International Space Station (via ISS HD Live application) on September 8, 2017 at 17:41 UTC.

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Video (mentioned), Text, Credits: NASA/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

NASA Gets "Eyed" by Major Hurricane Jose














NASA - EOS Aqua Mission logo / NOAA & NASA - GOES Mission logo.

Sep. 08, 2017

Jose (Eastern Atlantic Ocean)

NASA's Aqua satellite captured clear view of the eye of Hurricane Jose at it moved toward the Leeward Islands and strengthened into a Category 4 Hurricane on the Saffir-Simpson Hurricane Wind Scale. Aqua also analyzed the storm in infrared light showing powerful storms around the center, capable of heavy rainfall.


Image above: On Sept. 7 at 12:45 p.m. EDT (1645 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured a visible-light image of Hurricane Jose approaching the Leeward Islands. Image Credits: NASA Goddard MODIS Rapid Response Team.

On Sept. 8, the National Hurricane Center posted a Hurricane Watch for Antigua, Barbuda, and Anguilla, Saint Maarten, St. Martin and St. Barthelemy. A Tropical Storm Warning is in effect for Antigua, Barbuda, and Anguilla, and a Tropical Storm Watch is in effect for Montserrat, St Kitts, and Nevis, Saba and St. Eustatius.

Satellite Animation Sees Hurricanes Katia, Irma and Jose 

Video above: This animation of NOAA's GOES East satellite imagery from Sept. 5 at 7:45 a.m. EDT (1145 UTC) to Sept. 8 ending at 7:45 a.m. EDT (1145 UTC) shows Category 4 Hurricane Irma approach the Bahamas, followed by Hurricane Jose approaching the Leeward Islands. Hurricane Katia continues to spin in the southwestern Gulf of Mexico. Video Credits: NASA-NOAA.

The Atmospheric Infrared Sounder or AIRS instrument aboard NASA's Aqua satellite captured infrared temperature data on Hurricane Jose on Sept. 8 at 12:53 a.m. EDT (0453 UTC). The image showed some very cold cloud top temperatures as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius) around the center of circulation and in a feeder band of thunderstorms west of the center. NASA research has shown that cloud tops that cold are high in the troposphere and have the potential to generate heavy rainfall.

On Sept. 8 at 12:45 p.m. EDT (1645 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured a visible-light image of Hurricane Jose. The image showed a symmetrical storm with powerful bands of thunderstorms around a clear eye.


Image above: NASA's Aqua satellite captured infrared temperature data on Hurricane Jose on Sept. 8 at 12:53 a.m. EDT (0453 UTC). The image showed some very cold cloud top temperatures as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius). Image Credits: NASA JPL/Ed Olsen.

Jose's Location at 10 a.m. EDT on Sept. 8

The National Hurricane Center (NHC) said at 10 a.m. (1400 UTC), the eye of Hurricane Jose was located near 16.2 degrees north latitude and 56.9 degrees west longitude, about 435 miles (700 km) east-southeast of the Northern Leeward Islands. Jose was moving toward the west-northwest near 18 mph (30 kph).  A slower west-northwestward motion is expected during the next couple of days.

Maximum sustained winds are near 150 mph (240 kph) with higher gusts.  Jose is a category 4 hurricane on the Saffir-Simpson Hurricane Wind Scale.  The estimated minimum central pressure is 942 millibars.

On the forecast track, Jose is expected to be near the northern Leeward Islands on Saturday, Sept. 9.

For updates on Jose, visit: http://www.nhc.noaa.gov/

Aqua Satellite: https://www.nasa.gov/mission_pages/aqua/index.html

GOES (Geostationary Environmental Operational Satellites): http://www.nasa.gov/goes/

Images (mentioned), Video (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

After Cassini: Pondering the Saturn Mission's Legacy














NASA - Cassini Mission to Saturn patch / NASA - Europa Clipper Mission patch.

September 8, 2017

As the Cassini spacecraft nears the end of a long journey rich with scientific and technical accomplishments, it is already having a powerful influence on future exploration. In revealing that Saturn's moon Enceladus has many of the ingredients needed for life, the mission has inspired a pivot to the exploration of "ocean worlds" that has been sweeping planetary science over the past decade.


Image above: Cassini's discoveries are feeding forward into future exploration of the solar system. Image Credits: NASA/JPL-Caltech/Space Science Institute.

"Cassini has transformed our thinking in so many ways, but especially with regard to surprising places in the solar system where life could potentially gain a foothold," said Thomas Zurbuchen, associate administrator for NASA's Science Mission Directorate at Headquarters in Washington. "Congratulations to the entire Cassini team!"

Onward to Europa

Jupiter's moon Europa has been a prime target for future exploration since NASA's Galileo mission, in the late 1990s, found strong evidence for a salty global ocean of liquid water beneath its icy crust. But the more recent revelation that a much smaller moon like Enceladus could also have not only liquid water, but also chemical energy that could potentially power biology, was staggering.

Many lessons learned during Cassini's mission are being applied to planning NASA's Europa Clipper mission, planned for launch in the 2020s. Europa Clipper will fly by the icy ocean moon dozens of times to investigate its potential habitability, using an orbital tour design derived from the way Cassini has explored Saturn. The Europa Clipper mission will orbit the giant planet -- Jupiter in this case -- using gravitational assists from its large moons to maneuver the spacecraft into repeated close encounters with Europa. This is similar to the way Cassini's tour designers used the gravity of Saturn's moon Titan to continually shape their spacecraft's course.

Europa Clipper spacecraft. Animation Credit: NASA

In addition, many engineers and scientists from Cassini are serving on Europa Clipper and helping to develop its science investigations. For example, several members of the Cassini Ion and Neutral Mass Spectrometer and Cosmic Dust Analyzer teams are developing extremely sensitive, next-generation versions of their instruments for flight on Europa Clipper. What Cassini has learned about flying through the plume of material spraying from Enceladus will help inform planning for Europa Clipper, should plume activity be confirmed on Europa.

Returning to Saturn

Cassini also performed 127 close flybys of Saturn's haze-enshrouded moon Titan, showing it to be a remarkably complex factory for organic chemicals -- a natural laboratory for prebiotic chemistry. The mission investigated the cycling of liquid methane between clouds in its skies and great seas on its surface. By pulling back the veil on Titan, Cassini has ushered in a new era of extraterrestrial oceanography ­-- plumbing the depths of alien seas -- and delivered a fascinating example of earthlike processes occurring with chemistry and at temperatures markedly different from our home planet.

In the decades following Cassini, scientists hope to return to the Saturn system to follow up on the mission's many discoveries. Mission concepts under consideration include spacecraft to drift on the methane seas of Titan and fly through the Enceladus plume to collect and analyze samples for signs of biology.

Giant Planet Atmospheres

Atmospheric probes to all four of the outer planets have long been a priority for the science community, and the most recent Planetary Science Decadal Survey continues to support interest in sending such a mission to Saturn. By directly sampling Saturn's upper atmosphere during its last orbits and final plunge, Cassini is laying the groundwork for an eventual Saturn atmosphere probe.

Farther out in the solar system, scientists have long had their eyes set on exploring Uranus and Neptune. So far, each of these worlds has been visited by only one brief spacecraft flyby (Voyager 2, in 1986 and 1989, respectively). Collectively, Uranus and Neptune are referred to as "ice giant" planets, because they contain large amounts of materials (like water, ammonia and methane) that form ices in the cold depths of the outer solar system. This makes them fundamentally different from the gas giant planets, Jupiter and Saturn, which are almost all hydrogen and helium, and the inner, rocky planets like Earth or Mars. It's not clear exactly how and where the ice giants formed, why their magnetic fields are strangely oriented, and what drives geologic activity on some of their moons. These mysteries make them scientifically important, and this importance is enhanced by the discovery that many planets around other stars appear to be similar to our own ice giants.

Cassini Grand Finale. Animation Credits: NASA/JPL-Caltech/Space Science Institute

A variety of potential mission concepts are discussed in a recently completed study, delivered to NASA in preparation for the next Decadal Survey -- including orbiters, flybys and probes that would dive into Uranus' atmosphere to study its composition. Future missions to the ice giants might explore those worlds using an approach similar to Cassini's mission.

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.

Related links:

NASA's Europa Clipper: https://www.nasa.gov/europa

Cassini Ion and Neutral Mass Spectrometer: https://saturn.jpl.nasa.gov/ion-and-neutral-mass-spectrometer/

Planetary Science Decadal Survey: https://solarsystem.nasa.gov/2013decadal/

More information about Cassini:

https://www.nasa.gov/cassini
https://saturn.jpl.nasa.gov
http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Image (mentioned), Animations (mentioned), Text, Credits: NASA/JPL/Preston Dyches.

Greetings, Orbiter.ch

jeudi 7 septembre 2017

NASA/UCI Find Evidence of Sea Level 'Fingerprints'











NASA - GRACE Mission patch.

Sept. 7, 2017

New research will aid in sea level projections


Animation above: Sea level rise fingerprints calculated from observations of mass changes in Greenland, Antarctica, continental glaciers and ice caps, and land water storage made by the GRACE satellites, January 2003 to April 2014. Animation Credits: NASA/UCI.

Researchers from NASA’s Jet Propulsion Laboratory in Pasadena, California, and the University of California, Irvine, have reported the first detection of sea level “fingerprints” in ocean observations: detectable patterns of sea level variability around the world resulting from changes in water storage on Earth’s continents and in the mass of ice sheets. The results will give scientists confidence they can use these data to determine how much the sea level will rise at any point on the global ocean as a result of glacier ice melt.

As ice sheets and glaciers undergo climate-related melting, they alter Earth’s gravity field, resulting in sea level changes that aren’t uniform around the globe. For example, when a glacier loses ice mass, its gravitational attraction is reduced. Ocean waters nearby move away, causing sea level to rise faster far away from the glacier. The resulting pattern of sea level change is known as a sea level fingerprint. Certain regions, particularly in Earth’s middle and low latitudes, are hit harder, and Greenland and Antarctica contribute differently to the process. For instance, sea level rise in California and Florida generated by the melting of the Antarctic ice sheet is up to 52 percent greater than its average effect on the rest of the world.

GRACE satellites. Image Credits: NASA/JPL

To calculate sea level fingerprints associated with the loss of ice from glaciers and ice sheets and from changes in land water storage, the team used gravity data collected by the twin satellites of the U.S./German Gravity Recovery and Climate Experiment (GRACE) between April 2002 and October 2014. During that time, the loss of mass from land ice and from changes in land water storage increased global average sea level by about 0.07 inch (1.8 millimeters) per year, with 43 percent of the increased water mass coming from Greenland, 16 percent from Antarctica and 30 percent from mountain glaciers. The scientists then verified their calculations of sea level fingerprints using readings of ocean-bottom pressure from stations in the tropics.


Image above: Sea level fingerprints (patterns of variation in sea level rise) calculated from GRACE satellite observations, 2002-2014. The blue contour (1.8 millimeters per year) shows the average sea level rise if all the water added to the ocean were spread uniformly around Earth. Image Credits: NASA/UCI.

“Scientists have a solid understanding of the physics of sea level fingerprints, but we’ve never had a direct detection of the phenomenon until now,” said co-author Isabella Velicogna, UCI professor of Earth system science and JPL research scientist.

“It was very exciting to observe the sea level fingerprints in the tropics, far from the glaciers and ice sheets,” said lead author Chia-Wei Hsu, a graduate student researcher at UCI.

The findings are published today in the journal Geophysical Research Letters. The research project was supported by UCI and NASA’s Earth Science Division.

GRACE is a joint NASA mission with the German Aerospace Center (DLR) and the German Research Center for Geosciences (GFZ), in partnership with the University of Texas at Austin. For more information on NASA’s GRACE mission, visit: https://grace.jpl.nasa.gov/

Climate: https://www.nasa.gov/subject/3127/climate

Animation (mentioned), Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Alan Buis/UC Irvine/Brian Bell.

Greetings, Orbiter.ch

SpaceX - OTV-5 Launch Mission Success















SpaceX - Falcon 9 / OTV-5 Mission logo / USAF - OTV-5 Mission patch.

Sept. 7, 2017

Falcon 9 carrying OTV-5 lift-off. Image Credits: SpaceX/Orbiter.ch Aerospace

On Thursday, September 7 at 10:00 am EDT, SpaceX successfully launched the Orbital Test Vehicle 5 (OTV-5) payload from Launch Complex 39A (LC-39A) at NASA’s Kennedy Space Center in Florida.

Orbital Test Vehicle 5 (OTV-5) Mission

Following stage separation, Falcon 9’s first stage successfully landed at SpaceX’s Landing Zone 1 (LZ-1) at Cape Canaveral Air Force Station, Florida.

U.S. military’s X-37B. Image Credit: Boeing

A SpaceX Falcon 9 rocket launches the U.S. military’s X-37B, a spaceplane also called the Orbital Test Vehicle, on the program’s fifth mission.

For more infomation about X-37B, visit: https://en.wikipedia.org/wiki/Boeing_X-37

For more information about SpaceX, visit: http://www.spacex.com/

Images (mentioned), Video, Text, Credits: SpaceX/Orbiter.ch Aerospace.

Greetings, Orbiter.ch

Satellites Show Different Sides of Hurricane Irma















NASA - EOS Aqua Mission logo / NASA - Suomi NPP Mission patch.

Sept. 7, 2017

Irma (Atlantic Ocean)

Satellite imagery from NASA's Aqua satellite and NASA-NOAA's Suomi NPP satellite have provided different data on the still Category 5 Hurricane Irma as it headed for the Turks and Caicos Islands. 

NASA's Aqua Satellite Imagery

On Sept. 6 at 1:45 p.m. EDT (1745 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured a visible-light image of Hurricane Irma over the Leeward Islands and Puerto Rico. The image revealed a clear eye with powerful bands of thunderstorms circling the eye. 


Image above: On Sept. 6 at 1:45 p.m. EDT (1745 UTC) the Moderate Resolution Imaging Spectroradiometer or MODIS instrument aboard NASA's Aqua satellite captured a visible-light image of Hurricane Irma over the Leeward Islands and Puerto Rico. Image Credits: NASA Goddard MODIS Rapid Response Team.

On Sept. 7, when Aqua passed over Irma again, another instrument aboard Aqua gathered temperature data on the storm's clouds, which tell forecasters where the strongest parts of the hurricane is located. The colder the cloud tops, the higher the storm, and the stronger it is.

The Atmospheric Infrared Sounder or AIRS instrument aboard NASA's Aqua satellite captured infrared temperature data on Hurricane Irma on Sept. 7 at 1:47 a.m. EDT (0547 UTC). The image showed a clear eye and very cold cloud top temperatures as cold as cold as minus 83.1 degrees Celsius (minus 117.7 degrees Fahrenheit). NASA-NOAA's Suomi NPP satellite confirmed that data.  At that time, the southwestern quadrant of the storm was over Puerto Rico.


Image above: NASA's Aqua satellite captured infrared temperature data on Hurricane Irma on Sept. 7 at 1:47 a.m. EDT (0547 UTC). The image showed a clear eye and very cold cloud top temperatures as cold as minus 63 degrees Fahrenheit (minus 53 degrees Celsius). The southwestern quadrant of the storm was over Puerto Rico. Image Credits: NASA JPL/Ed Olsen.

Suomi NPP Satellite Collects Night-Time Data on Irma

At 2:57 a.m. AST/EDT on Sept. 7, the VIIRS instrument on board the NOAA/NASA Suomi NPP satellite captured data on Irma as the storm passed to the northwest of the island of Puerto Rico. In a night-time image created by Suomi NPP's Day Night Band, the waning gibbous moon highlighted the convection around Irma's eye and tropospheric gravity waves were present around the well-defined eyewall.


Image above: At 2:57 a.m. AST/EDT on Sept. 7, Suomi NPP's Day Night Band imagery and the waning gibbous moon highlighted the convection around Irma's eye and tropospheric gravity waves were present around the well-defined eyewall. Image Credits: NOAA/NASA/UWM-CIMSS, William Straka III.

Infrared imagery from Suomi NPP revealed cloud top temperatures as cold as 190 kelvin (minus 83.1 degrees Celsius/minus 117.7 degrees Fahrenheit) from Irma's northern quadrant, stretching through the eastern side to the south of the eye. Those cloud top temperatures indicated the most powerful storms in Irma, stretching high into the troposphere. NASA research has shown that cloud top temperatures that cold can generate very heavy rain.


Image above: At 2:57 a.m. AST/EDT on Sept. 7, Infrared imagery from Suomi NPP revealed cloud top temperatures as cold as (white) 190 kelvin (minus 83.1 degrees Celsius/minus 117.7 degrees Fahrenheit) from Irma's northern quadrant, stretching through the eastern side to the south of the eye. Image Credits: NOAA/NASA/UWM-CIMSS, William Straka III.

Watches and Warnings in Effect on Sept. 7

On Sept. 7, hurricane and storm surge watches are now in effect for portions of south Florida and the Florida Keys. There are many warnings and watches in effect.

A Storm Surge Watch is in effect from Jupiter Inlet southward around the Florida peninsula to Bonita Beach, Florida, and for the Florida Keys.

A Hurricane Warning is in effect for the Dominican Republic from Cabo Engano to the northern border with Haiti; Haiti from the northern border with the Dominican Republic to Le Mole St. Nicholas; the southeastern Bahamas and the Turks and Caicos Islands; the central Bahamas and the northwestern Bahamas.

EOS Aqua satellite. Image Credit: NASA

A Hurricane Watch is in effect from Jupiter Inlet southward around the Florida peninsula to Bonita Beach, Florida, the Florida Keys, Lake Okeechobee,  Florida Bay, and for Cuba from Matanzas province eastward to Guantanamo province. A Tropical Storm Warning is in effect for the Dominican Republic from south of Cabo Engano westward to the southern border with Haiti; Haiti from south of Le Mole St. Nicholas to Port-Au-Prince; Cuba provinces of Guantanamo, Holguin, Las Tunas, Camaguey, Ciego de Avila, Sancti Spiritus and Villa Clara.

NHC Official Location for Irma on Sept. 7

At 11 a.m. EDT (1500 UTC) the National Hurricane Center (NHC) said that the distinct eye of Hurricane Irma was located near 20.4 degrees north latitude and 69.7 degrees west longitude.

Irma was moving toward the west-northwest near 16 mph (26 kph), and this general motion is expected to continue with some decrease in forward speed for the next couple of days.  On the forecast track, the eye of Irma should continue to move just north of the coast of Hispaniola today, be near the Turks and Caicos and southeastern Bahamas by this evening, and then be near the central Bahamas by Friday, Sept. 8.

Suomi NPP satellite. Image Credit: NASA

Maximum sustained winds are near 175 mph (280 kph) with higher gusts.  Irma is a category 5 hurricane on the Saffir-Simpson Hurricane Wind Scale.  Some fluctuations in intensity are likely during the next day or two, but Irma is forecast to remain a powerful category 4 or 5 hurricane during the next couple of days. The minimum central pressure reported by an Air Force plane was 921 millibars.

NHC forecaster Lixion Avila noted "There are no obvious reasons why Irma will not remain a powerful hurricane for the next 3 days while approaching Florida. Thereafter, an increase in the wind shear could lead to gradual weakening, but Irma is expected to remain a major hurricane until landfall occurs."

For updated forecasts on Irma, visit: http://www.nhc.noaa.gov/.

Related links:

Aqua Satellite: https://www.nasa.gov/mission_pages/aqua/index.html

Suomi NPP (National Polar-orbiting Partnership): http://www.nasa.gov/mission_pages/NPP/main/index.html

Images (mentioned), Text, Credits: NASA's Goddard Space Flight Center, by Rob Gutro.

Greetings, Orbiter.ch

Space Science Work Today as New Crew Waits for Launch & ISS Passes Over Hurricane Irma












ISS - Expedition 53 Mission patch.

September 7, 2017

ISS Passes Over Hurricane Irma - 9/6/2017

Video above: The International Space Station’s external cameras captured another dramatic view of Hurricane Irma as it made landfall in the Caribbean Sept. 6. The powerful Category 5 storm with sustained winds of 185 mph made landfall on several islands while continuing on a westward track. Irma is expected to bring severe wind and rain to several islands in the Caribbean over the next several days with the potential to impact the Florida peninsula by week’s end. Video Credits: NASA.

Today’s science tasks included an inspection on an advanced microscope and readying a magnetic field experiment. The crew also worked on a failed electrical device that was robotically transferred to the Kibo laboratory module in early August.

Commander Randy Bresnik and Flight Engineer Paolo Nespoli removed a failed Main Bus Switching Unit (MBSU) from Kibo’s airlock today. The duo swapped out some electronics gear in the MBSU and tested the device while it was connected to a laptop computer.


Image above: Expedition 53-54 prime and backup crew members pose in front of the Soyuz MS-06 rocket that will launch Sept. 12 carrying Alexander Misurkin, Mark Vande Hei and Joe Acaba to the space station. Image Credits: Gagarin Cosmonaut Training Center/Irina Peshkova.

Nespoli started his day setting up the Magvector magnetic field experiment for operations set to begin next week. The study investigates how Earth’s magnetic field interacts with an electrical conductor potentially improving electrical experiments in space.

As Bresnik was wrapping up his MBSU maintenance work, Nespoli began inspecting advanced microscope gear. The variety of new Light Microscopy Module gear had been recently launched and was being checked for shattered materials.

ISS Pass Over Hurricane Irma 9/7/2017

Video above: Updated caption for today: External cameras on the International Space Station captured views during an overhead pass of Hurricane Irma on Sept. 7, the third pass this week. The Category 5 storm with sustained winds of 180 mph has brought devastating wind and rains to several islands in the Caribbean, with a hurricane watch in effect for much of Cuba and the potential to begin impacting the Florida peninsula by week’s end. Note: The second view appears in black and white due to an issue with the sensor on the external camera. Video Credit: NASA.

Three new Expedition 53 crew members are at the Baikonur Cosmodrome just five days away from their launch to the International Space Station. Two NASA astronauts and a Roscosmos cosmonaut are in final preparations checking their Sokol launch and entry suits and examining their Soyuz MS-06 spacecraft.

Related links:

Expedition 53: https://www.nasa.gov/mission_pages/station/expeditions/expedition53/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Videos (mentioned), Text, Credits: NASA/Mark Garcia.

Best regards, Orbiter.ch

Staggering Structure












NASA - Cassini Mission to Saturn patch.

Sept. 7, 2017


This view from NASA's Cassini spacecraft shows a wave structure in Saturn's rings known as the Janus 2:1 spiral density wave. Resulting from the same process that creates spiral galaxies, spiral density waves in Saturn’s rings are much more tightly wound. In this case, every second wave crest is actually the same spiral arm which has encircled the entire planet multiple times.

This is the only major density wave visible in Saturn's B ring. Most of the B ring is characterized by structures that dominate the areas where density waves might otherwise occur, but this innermost portion of the B ring is different.

The radius from Saturn at which the wave originates (toward lower-right in this image) is 59,796 miles (96,233 kilometers) from the planet. At this location, ring particles orbit Saturn twice for every time the moon Janus orbits once, creating an orbital resonance. The wave propagates outward from the resonance (and away from Saturn), toward upper-left in this view. For reasons researchers do not entirely understand, damping of waves by larger ring structures is very weak at this location, so this wave is seen ringing for hundreds of bright wave crests, unlike density waves in Saturn's A ring.

The image gives the illusion that the ring plane is tilted away from the camera toward upper-left, but this is not the case. Because of the mechanics of how this kind of wave propagates, the wavelength decreases with distance from the resonance. Thus, the upper-left of the image is just as close to the camera as the lower-right, while the wavelength of the density wave is simply shorter.

This wave is remarkable because Janus, the moon that generates it, is in a strange orbital configuration. Janus and Epimetheus (see PIA12602) share practically the same orbit and trade places every four years. Every time one of those orbit swaps takes place, the ring at this location responds, spawning a new crest in the wave. The distance between any pair of crests corresponds to four years’ worth of the wave propagating downstream from the resonance, which means the wave seen here encodes many decades’ worth of the orbital history of Janus and Epimetheus. According to this interpretation, the part of the wave at the very upper-left of this image corresponds to the positions of Janus and Epimetheus around the time of the Voyager flybys in 1980 and 1981, which is the time at which Janus and Epimetheus were first proven to be two distinct objects (they were first observed in 1966).

Cassini Grand Finale

Epimetheus also generates waves at this location, but they are swamped by the waves from Janus, since Janus is the larger of the two moons.

This image was taken on June 4, 2017, with the Cassini spacecraft narrow-angle camera. The image was acquired on the sunlit side of the rings from a distance of 47,000 miles (76,000 kilometers) away from the area pictured. The image scale is 1,730 feet (530 meters) per pixel. The phase angle, or sun-ring-spacecraft angle, is 90 degrees.

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 Caltech 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 https://www.nasa.gov/cassini. The Cassini imaging team homepage is at https://ciclops.org and ESA website: http://www.esa.int/Our_Activities/Space_Science/Cassini-Huygens

Related link:

PIA12602: https://photojournal.jpl.nasa.gov/catalog/PIA12602

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

Greetings, Orbiter.ch

Weekly Recap From the Expedition Lead Scientist, Week of August 28, 2017












ISS - Expedition 53 Mission patch / ISS - Expedition 52 Mission patch.

Sept. 7, 2017

International Space Station (ISS). Image Credit: NASA

(Highlights: Week of August 28, 2017) - As International Space Station crew members Peggy Whitson, Jack Fischer and Fyodor Yurchikhin packed their bags to return to Earth, their thoughts were with the residents of the Gulf Coast of Texas -- which includes many colleagues at NASA's Johnson Space Center in Houston -- as Hurricane Harvey struck the area, causing severe flooding and devastation. However, they also continued a record-breaking run of science on the orbiting laboratory. During Expedition 52, crew science activities averaged more than 60 hours a week, eclipsing the previous average of around 45 hours a week.

A lot of these final investigations before returning to Earth involve research of the effects of long-duration space travel on humans. Crew members performed an investigation examining the environment in which they live and work from a practical and psychological point of view with the Habitability Assessment of International Space Station (Habitability). This investigation gives station residents the opportunity to make observations about the orbiting laboratory they call home.


Image above: NASA astronaut Peggy Whitson works on cell transfers using the Advanced Space Experiment Processor (ADSEPT) for the Cardiac Myocytes investigation on the International Space Station. Image Credit: NASA.

For crew members on long-duration space missions, cabin designs must balance comfort and efficiency. The crew's thoughts and ideas can help spacecraft designers understand how much habitable volume is needed, including whether a mission's duration impacts how much personal space crew members need. The crew answers questionnaires and records video tours while making suggestions on layout and internal design. Results from the Habitability investigation will provide insight and contribute to the design of future spacecraft. It may also apply to workers who live and work in confined spaces with limited volume and resources on Earth, such as remote polar research stations, ocean drilling rigs or mines.

Astronauts also completed a session for the Effects of Long-Duration Microgravity on Fine Motor Skills (Fine Motor Skills) investigation. Fine motor skills are crucial for successfully interacting with touch-based technologies, repairing sensitive equipment and a variety of other tasks. The investigation is the first fine motor skills study to measure long-term microgravity exposure, different phases of microgravity adaptation and sensorimotor recovery after returning to Earth’s gravity. The investigation involves a series of interactive tasks on a touchscreen tablet and may have wide-reaching benefits for elderly patients, people with motor disorders or patients with brain injuries on Earth undergoing rehabilitation for conditions that impair fine motor control.


Image above: Space station crew members captured this image as they passed over Hurricane Harvey on Aug. 30. The storm caused major devastation to the Gulf Coast of Texas and NASA's Johnson Space Center in Houston was forced to temporarily close as a safety precaution. Image Credit: NASA.

A study of the immune system of astronauts, which is altered during spaceflight, was also conducted on the space station. The Functional Immune Alterations, Latent Herpesvirus Reactivation, Psychological Stress and Clinical Incidence Onboard the International Space Station (Functional Immune) investigation analyzes blood and saliva samples to determine the changes taking place in crew members' immune systems during flight. Any change, so far away from readily available treatment, could increase the likelihood of adverse health events in space travelers. This study looks for environmental, human and stress-related factors as they relate to immunity levels. Results are expected to provide new insight into the health risks of long-duration space travel. The investigation also provides a unique view of the subtle changes in the immune system that may occur before symptoms become evident. This could help scientists and doctors pinpoint the onset of a particular illness and suggest treatments to boost the immune system and prevent full-blown infections and diseases on Earth.

Jack and Peggy's Excellent Adventure

Video above: NASA released an edited video stream of a recent EVA by NASA astronauts Peggy Whitson and Jack Fischer. They were wearing small high-definition cameras and NASA added the space to ground audio to give viewers a new perspective of what it is like to go on a spacewalk outside the International Space Station. Video Credit: NASA.

Progress was made on other investigations this week, including: Lighting Effects, STaARS BioScience, Biochem Profile, STaARS-iFUNGUS, Body Measures, Genes in Space-4, NeuroMapping, Meteor, Lung Tissue, Microbial Tracking, Cool Flames, and ISS Ham Radio (ARISS).

Related links:

Habitability Assessment of International Space Station (Habitability): https://www.nasa.gov/mission_pages/station/research/experiments/1772.html

Fine Motor Skills: http://www.nasa.gov/mission_pages/station/research/experiments/1767.html

Functional Immune: https://www.nasa.gov/mission_pages/station/research/experiments/2277.html

Lighting Effects: https://www.nasa.gov/mission_pages/station/research/experiments/2279.html

STaARS BioScience: https://www.nasa.gov/mission_pages/station/research/experiments/2512.html

Biochem Profile: http://www.nasa.gov/mission_pages/station/research/experiments/1008.html

STaARS-iFUNGUS: https://www.nasa.gov/mission_pages/station/research/experiments/2492.html

Body Measures: https://www.nasa.gov/mission_pages/station/research/experiments/1070.html

Genes in Space-4: https://www.nasa.gov/mission_pages/station/research/experiments/2524.html

NeuroMapping: https://www.nasa.gov/mission_pages/station/research/experiments/1007.html

Meteor: https://www.nasa.gov/mission_pages/station/research/experiments/1323.html

Lung Tissue: https://www.nasa.gov/mission_pages/station/research/experiments/2399.html

Microbial Tracking: https://www.nasa.gov/mission_pages/station/research/experiments/1920.html

Cool Flames: https://www.nasa.gov/mission_pages/station/research/experiments/1947.html

ISS Ham Radio (ARISS): http://www.nasa.gov/mission_pages/station/research/experiments/346.html

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/index.html

International Space Station (ISS): https://www.nasa.gov/mission_pages/station/main/index.html

Images (mentioned), Video (mentioned), Text, Credits: NASA/Kristine Rainey/Jorge Sotomayor, Lead Increment Scientist Expeditions 51 & 52.

Best regards, Orbiter.ch

New tools for exploring the surface of Mars: the Planetary SUrface Portal (PSUP) and the iMars webGIS












ESA - Mars Express Mission patch.

07 September 2017

In past decades, spacecraft have sent back huge amounts of complex data about Mars, providing a wealth of information about the planet. More than ever, the scientific community needs a way to sift through, compare, and analyse these data, prompting the development of two new tools for exploring the surface of the Red Planet: the iMars webGIS and the Planetary SUrface Portal (PSUP).

Among the many different targets for investigation in our Solar System, Mars is a special case due to the sheer volume of data we have collected from the numerous spacecraft that have flown past, orbited, landed on, or traversed the surface of the Red Planet.


Image above: Artist's impression of Mars Express. Image Credits: ESA/ATG medialab.

Two new tools have now been developed to allow scientists to access processed data from missions including ESA's Mars Express mission and from the ESA Planetary Science Archive. Users can browse data (high-level and raw), view image footprints, combine and compare datasets from different orbits, missions, and spacecraft instruments, hunt for signs of how the Martian surface has changed over time, and more.

The Planetary SUrface Portal (PSUP): Visualising the Martian surface

PSUP was developed by experts at the observatories of Paris Sud (OSUPS) and Lyon (OSUL), and is an important legacy of ESA's Mars Express mission. The web portal allows scientists to browse, process, download, distribute, merge, and visualise high-level data mainly related to the Martian surface from Mars Express, and NASA's Mars Reconnaissance Orbiter and 2001 Mars Odyssey missions.

"PSUP is unique due to the quality of the high-level hyperspectral data available, all of which are processed and validated," says François Poulet, science manager of PSUP and an astronomer at Institut d'Astrophysique Spatiale, CNRS/Université Paris-Sud, France. "It's a way to combine and display data of Mars, on both a global and local scale, in one place."


Image above: Using PSUP: Viewing OMEGA data of Mars' surface emissivity. Imag Credits: ESA/PSUP (OSUPS/OSUL).

PSUP contains two key modules: MarsSI (Mars System Information), which lets users access, process, and download surface data–including a unique tool to create local digital terrain models on demand–and Mars Visu, which allows users to visualise various datasets in 3D–including global mineralogical maps, geomorphologic maps, and various other catalogues.

"The digital models of Mars' surface available on PSUP are created via state-of-the-art data reduction methods, and the portal contains impressive global mineral maps and calibrated data from OMEGA that'll be updated as the results of new observations and analyses arrive," adds Poulet. OMEGA is the Infrared Mineralogical Mapping Spectrometer aboard Mars Express; the instrument has been mapping the Martian surface since it arrived at Mars in late 2003. "I'm very proud that PSUP can provide such high-quality processed products and data analysis from more than a decade of observations to both the science community and public," says Poulet.


Image above: Using PSUP: Viewing OMEGA mineralogical data of Mars' pyroxene content. Image Credits: ESA/PSUP (OSUPS/OSUL).

Poulet has been closely involved in analysing regions of Mars as part of a project to identify potential landing sites for the ExoMars 2020 mission, as has the science manager for MarsSI, Cathy Quantin-Nataf.

"As an example of an important application of these tools, without the PSUP, and MarsSI in particular, it wouldn't have been possible to propose what was then an unknown location (Oxia Planum) as the landing site for ExoMars 2020," says Quantin-Nataf, a professor at University of Lyon, France. "Assessing Oxia Planum required us to process tons of data that hadn't yet been explored–this would have taken an unreasonable amount of time without MarsSI."

The iMars web-based geographic information system: Identifying signs of a changing surface

The iMars web-based geographic information system, or iMars webGIS, brings together space-based imaging and high-precision 3D data of Mars from Mars Express' High Resolution Stereo Camera (HRSC), which can be displayed alongside a vast quantity of additional datasets and images from other Mars missions.

The HRSC data are automatically adjusted to each other ('bundle-block adjusted'), mapped onto the same coordinate system ('co-registered' and 'orthorectified') using highly precise digital terrain models (derived from stereo matching and tied to global control terrain data from the Mars Orbiter Laser Altimeter (MOLA) on NASA's Mars Global Surveyor ('terrain-corrected').


Image above: Using iMars: Viewing Mars Express data of the MC11 quadrangle. Image Credits: ESA/iMars (UCL/FUB/EPFL/UNOTT/UoS).

The iMars webGIS displays HRSC high-level data products (digital terrain models and orthoimages) covering approximately half of the Martian surface–this can be used as 'base data' against which to explore and compare other observations of Mars.

Additional data from the Mars Reconnaissance Orbiter's Context Camera (CTX) are available over around 20% of the same area; where these datasets overlap, the two can be co-registered and again used as base data for further high-resolution datasets and models (such as those from Mars Global Surveyor's Mars Orbiter Camera (MOC) and High Resolution Imaging Science Experiment (HiRISE).

"iMars is an expert tool for detecting and visualising changes on Mars' surface over time," explains Sebastian Walter of Freie Universitaet Berlin, Germany, who led the management and development of iMars' webGIS element. "To detect changes such as landslides, new impact craters, and the evolution of the polar caps and frosts, we need to precisely combine several images of the same spot on the ground taken at different times–and that's incredibly difficult to do."


Image above: Using iMars: Viewing Mars Express data of Valles Marineris. Image Credits: ESA/iMars (UCL/FUB/EPFL/UNOTT/UoS).

Thousands of images exist from past ESA and NASA campaigns at Mars. Combining and aligning these can be problematic because the exact positioning ('pointing') of the camera at the moment that an image is taken differs between orbits, cameras, and missions.

"If you stacked two images of the same feature atop one another, that feature would most probably not line up in the same spot," adds Walter. "iMars solves this problem by automatically co-registering many of the available images to a common baseline, and the webGIS allows us to view and visualise all the data in one place. This co-registering is key to iMars' value; it allows scientists to accurately and comprehensively compare data across missions, as it's all displayed in the same reference system."

The iMars webGIS provides a way to comprehensively view and explore the Martian surface across both space and time. Rather than merging images taken across different orbits into a single mosaic, as is the usual way to display planetary data, iMars keeps and simultaneously displays datasets from different orbits separately in order to capture snapshots of the surface at specific moments in time (thus making it easier to identify any changes).

"Using the system makes the daily work of planetary scientists easier, and the outcomes more robust," says Walter. "All iMars data are pre-processed, which saves a lot of time that would otherwise be needed to find, download, process and visualise a dataset manually. It also includes unique capabilities for visualisation–it's possible, for example, to "play" the different images in time like a movie–but even if only used for locating features or images from the different available datasets and comparing them through time, it's a great little helper tool."

The iMars team has put together a video tutorial on how to use the system, available here: https://www.youtube.com/watch?v=mPfd4n1CZQw

Future development: New data, new features, new planets

The further development of both iMars and PSUP is ongoing. For example, the iMars webGIS features new Mars Express HRSC topographic data for the area surrounding the residual South Polar Cap, and the team is currently working on applying the same approach to the North Polar Cap.

"We also plan to add all available HRSC images, and the tool will eventually allow users to download the data," says Walter. "As more data are processed in the future, I hope that a great deal more of Mars will become completely covered on the system. For example, currently, only the MC11 quadrangle is completely available–this will improve in time."

Mars' surface is split into 30 quadrangles for easy identification by the United States Geological Survey (USGS); the MC11 quadrangle, otherwise known as the Oxia Palus quadrangle, contains Oxia Planum and Mawrth Vallis, both of which are candidate landing sites for ExoMars 2020, and the landing site for NASA's Mars Pathfinder mission in 1997.

Future development is also planned for PSUP. "Alongside adding new datasets, mineral abundance maps, and global image mosaics, we hope that we can use PSUP to create products for the public as well as for the science community; for example, at IAS we've started to develop a tool that'll allow a 3D virtual tour of any set–or 'cube', as it's known–of OMEGA observations available via PSUP," adds Poulet.

"We also plan to further improve our facility to include radar data for Mars," adds Quantin-Nataf, "and hope to extend the application to other planetary bodies: the Moon, Titan, and others!"

As well as enabling scientists at all levels and across all disciplines to comprehensively explore and analyse the Martian surface, access and share data, and locate high-quality processed data swiftly and easily, tools such as iMars webGIS and PSUP have a direct impact on ongoing mission plans.

"Such systems and portals can be used to help us identify potential landing sites for our missions to Mars," says Dmitri Titov, ESA Project Scientist for Mars Express. "Selecting a landing site is crucial to mission success, and in order to choose the right one, we need to know exactly what we might hope to find in a given location, and why it may be better than another one."

"The Mars Express mission has sent back a wealth of high-quality data from Mars, and it is still going strong," he adds. "Making it possible to access, process, compare, and understand large amounts of this data is exactly what we need for our appraisals of future landing sites–and exactly what tools such as iMars webGIS and PSUP will help us to do."

Notes for editors:

The iMars webGIS can be accessed http://imars.planet.fu-berlin.de/ or http://www.i-mars.eu/web-gis. More information about iMars webGIS can be found in The iMars WebGIS – Space-Time Queries and Dynamic Time Series of Single Images by S.H.G. Walter et al., Lunar and Planetary Science XLVIII (2017), (http://www.lpi.usra.edu/meetings/lpsc2017/pdf/1066.pdf).

The Planetary SUrface Portal (PSUP) can be accessed here: http://psup.ias.u-psud.fr/

Details about PSUP can be found in PSUP: A Planetary SUrface Portal, by F. Poulet et al., Planetary and Space Science, 2017; doi: 10.1016/j.pss.2017.01.016.

ESA's Mars Express mission launched in 2003, arrived at Mars later that year, and has been sending back high-quality data since. More information about the mission can be found here: http://sci.esa.int/mars-express/

Related links:

PSUP: A Planetary SUrface Portal: https://dx.doi.org/10.1016/j.pss.2017.01.016

ESA Planetary Science Archive: https://archives.esac.esa.int/psa/

ExoMars 2020 mission: http://exploration.esa.int/mars/48088-mission-overview/

Paris Sud (OSUPS): https://www.ias.u-psud.fr/fr/content/lobservatoire-paris-sud-osups

Lyon (OSUL): http://observatoire.univ-lyon1.fr/

NASA's Mars Reconnaissance Orbiter (MRO): https://mars.nasa.gov/mro/

NASA's 2001 Mars Odyssey: https://mars.nasa.gov/odyssey/

iMars web-based geographic information system: http://imars.planet.fu-berlin.de/

Mars Express High Resolution Stereo Camera (HRSC): http://www.dlr.de/dlr/en/desktopdefault.aspx/tabid-10364/548_read-400/#/gallery/657

NASA's Mars Global Surveyor: https://mars.nasa.gov/programmissions/missions/past/globalsurveyor/

Mars Orbiter Laser Altimeter (MOLA): https://attic.gsfc.nasa.gov/mola/about.html

Mars Reconnaissance Orbiter's Context Camera (CTX): https://mars.nasa.gov/mro/mission/instruments/ctx/

Mars Orbiter Camera (MOC): http://www.msss.com/all_projects/mgs-mars-orbiter-camera.php

High Resolution Imaging Science Experiment (HiRISE): https://hirise.lpl.arizona.edu/index.php

Images (mentioned), Text, Credits: ESA/Dmitri Titov/CNRS/Université Paris-Sud/François Poulet/University of Lyon/Cathy Quantin-Nataf/Freie Universitaet Berlin/Sebastian Walter.

Best regards, Orbiter.ch