Pioneer Galileo navigation fixes recognised by ESA

ESA - Galileo logo.

23 June 2014

Billions of satnav position fixes are performed daily, but determining your place in the world using Europe’s Galileo system is quite new. So ESA offered to issue certificates for the very first 50 Galileo fixes – provoking responses from across the whole world.

The surprise was the extent of Galileo’s reach. While half the applications came from Galileo’s home continent, others came from the rest of the world, including Australia, Canada, China, Egypt, New Zealand, Russia, USA and Vietnam.

Galileo positioning while driving in Slovakia

The first two satellites of Europe’s Galileo constellation were launched in October 2011, followed by two more a year later. Four is the minimum needed for determining position, allowing testing of the full Galileo system to begin.

The historic first positioning fix using only Europe’s civil-owned navigation system took place at ESA’s Navigation Laboratory in its ESTEC technical centre in Noordwijk, the Netherlands, on 12 March 2013.

Early Galileo positioning fixes worldwide

Galileo’s navigation signals could be picked up anywhere in the world that the orbiting satellites come into view, however. And plenty of equipped teams from industry, universities, research centres and government institutions took the opportunity to perform their own – along with a couple of private individuals.

The Galileo team knew of fixes being performed on an informal basis. The idea came to mark the anniversary of the first positioning fix by issuing commemorative certificates to groups who had picked up the signals to perform their own fixes.

Four Galileo satellites

Teams were asked to include details of the receiver they used, the start and finish of the fixes in Universal Time Coordinated (UTC) and a plot of their latitude/longitude positioning overlaid on a map, such as Google Earth.

Italy turned out to be the single best represented country in Europe, with six separate fixes, followed closely by Germany and the UK with five fixes each. Several groups achieved fixes on the very same day as ESA.

Most of the receivers were software-based radio systems, with signal processing performed by software on a computer linked to a radio-frequency front end. Professional receivers were also customised.

Pedestrian Galileo positioning in New Zealand

One private individual from Gdansk, Poland, used his own receiver to perform a fix, intended for amateur rocketry. Another individual in Pec, Hungary, also achieved a fix with a modified receiver.

“Most of the applications were obtained with static receivers and simple position fixes with Galileo’s Open Service signals,” explains Galileo engineer Gaetano Galluzzo. “There were also some special cases, however.”

Galileo positioning in Vietnam

These included ‘precise point positioning’ where offline processing is applied to give extremely precise centimetre-scale positioning – typically used in surveying, the oil and gas industries or precision agriculture.  Some of these were actually performed before the first realtime positioning fixes.

Belgium’s Royal Military Academy performed Galileo’s first position fix at sea, aboard Belgian frigate Leopold-I, which sailed along the Norwegian coast.

A navigation company from New Zealand performed positioning as they walked, while a technology firm in Slovakia performed drive testing.

Sources of Galileo certification applications

A German telecom company made use of the satellite signals for timing and network synchronisation – one of the most important applications of Galileo will be as a nanosecond-scale time source, enabling the effective synching of financial, power and data networks around the globe.

The certificates will be issued soon.

General use of Galileo will begin as more satellites join the first four in orbit so the first services can be rolled out. The next two Galileos are currently in French Guiana, beginning their preparations for launch.

It should take only a slight software update to ready the current generations of satnav receivers to work with Galileo signals. 

Related links:
About satellite navigation: http://www.esa.int/Our_Activities/Navigation/About_satellite_navigation2

Europe's satellite navigation services: http://www.esa.int/Our_Activities/Navigation/Europe_s_satellite_navigation_services

Galileo IOV phase information sheet: http://esamultimedia.esa.int/docs/Navigation/galileo_IOV_flyer_final.pdf

Images, Text, Credits: ESA / P. Carril / GoSpace.

Best regards, Orbiter.ch

NASA’s Mars Curiosity Rover Marks First Martian Year with Mission Successes

NASA - Mars Science Laboratory (MSL) logo.

June 23, 2014

Image above: NASA's Mars Curiosity Rover captures a selfie to mark a full Martian year -- 687 Earth days -- spent exploring the Red Planet. Image Credit: NASA/JPL-Caltech/MSSS.

NASA’s Mars Curiosity rover will complete a Martian year -- 687 Earth days -- on June 24, having accomplished the mission's main goal of determining whether Mars once offered environmental conditions favorable for microbial life.

One of Curiosity's first major findings after landing on the Red Planet in August 2012 was an ancient riverbed at its landing site. Nearby, at an area known as Yellowknife Bay, the mission met its main goal of determining whether the Martian Gale Crater ever was habitable for simple life forms. The answer, a historic "yes," came from two mudstone slabs that the rover sampled with its drill. Analysis of these samples revealed the site was once a lakebed with mild water, the essential elemental ingredients for life, and a type of chemical energy source used by some microbes on Earth. If Mars had living organisms, this would have been a good home for them.

Video above: Curiosity Rover Report: Mars rover completes its first Martian year. Video Credit: NASA/JPL.

Other important findings during the first Martian year include:

-- Assessing natural radiation levels both during the flight to Mars and on the Martian surface provides guidance for designing the protection needed for human missions to Mars.

-- Measurements of heavy-versus-light variants of elements in the Martian atmosphere indicate that much of Mars' early atmosphere disappeared by processes favoring loss of lighter atoms, such as from the top of the atmosphere. Other measurements found that the atmosphere holds very little, if any, methane, a gas that can be produced biologically.

-- The first determinations of the age of a rock on Mars and how long a rock has been exposed to harmful radiation provide prospects for learning when water flowed and for assessing degradation rates of organic compounds in rocks and soils.

Curiosity paused in driving this spring to drill and collect a sample from a sandstone site called Windjana. The rover currently is carrying some of the rock-powder sample collected at the site for follow-up analysis.

"Windjana has more magnetite than previous samples we've analyzed," said David Blake, principal investigator for Curiosity's Chemistry and Mineralogy (CheMin) instrument at NASA’s Ames Research Center, Moffett Field, California.  "A key question is whether this magnetite is a component of the original basalt or resulted from later processes, such as would happen in water-soaked basaltic sediments. The answer is important to our understanding of habitability and the nature of the early-Mars environment."

This map shows in red the route driven by NASA's Curiosity Mars rover from the "Bradbury Landing" location where it landed in August 2012 (blue star at upper right) to nearly the completion of its first Martian year. The white line shows the planned route ahead. Image Credit: NASA/JPL.

Preliminary indications are that the rock contains a more diverse mix of clay minerals than was found in the mission's only previously drilled rocks, the mudstone targets at Yellowknife Bay. Windjana also contains an unexpectedly high amount of the mineral orthoclase, This is a potassium-rich feldspar that is one of the most abundant minerals in Earth's crust that had never before been definitively detected on Mars.

This finding implies that some rocks on the Gale Crater rim, from which the Windjana sandstones are thought to have been derived, may have experienced complex geological processing, such as multiple episodes of melting.

"It's too early for conclusions, but we expect the results to help us connect what we learned at Yellowknife Bay to what we'll learn at Mount Sharp," said John Grotzinger, Curiosity Project Scientist at the California Institute of Technology, Pasadena. "Windjana is still within an area where a river flowed. We see signs of a complex history of interaction between water and rock."

Curiosity departed Windjana in mid-May and is advancing westward. It has covered about nine-tenths of a mile (1.5 kilometers) in 23 driving days and brought the mission's odometer tally up to 4.9 miles (7.9 kilometers).

Since wheel damage prompted a slow-down in driving late in 2013, the mission team has adjusted routes and driving methods to reduce the rate of damage.

For example, the mission team revised the planned route to future destinations on the lower slope of an area called Mount Sharp, where scientists expect geological layering will yield answers about ancient environments. Before Curiosity landed, scientists anticipated that the rover would need to reach Mount Sharp to meet the goal of determining whether the ancient environment was favorable for life. They found an answer much closer to the landing site. The findings so far have raised the bar for the work ahead. At Mount Sharp, the mission team will seek evidence not only of habitability, but also of how environments evolved and what conditions favored preservation of clues to whether life existed there.

The entry gate to the mountain is a gap in a band of dunes edging the mountain's northern flank that is approximately 2.4 miles (3.9 kilometers) ahead of the rover's current location. The new path will take Curiosity across sandy patches as well as rockier ground. Terrain mapping with use of imaging from NASA's Mars Reconnaissance Orbiter enables the charting of safer, though longer, routes.

The team expects its will need to continually adapt to the threats posed by the terrain to the rover's wheels but does not expect this will be a determining factor in the length of Curiosity's operational life.

"We are getting in some long drives using what we have learned," said Jim Erickson, Curiosity Project Manager at NASA's Jet Propulsion Laboratory (JPL) in Pasadena, California. "When you're exploring another planet, you expect surprises.  The sharp, embedded rocks were a bad surprise. Yellowknife Bay was a good surprise."

JPL manages NASA's Mars Science Laboratory Project for NASA's Science Mission Directorate at the agency’s headquarters in Washington, and built the project's Curiosity rover.

For more information about Curiosity, visit: http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/

You can follow the mission on Facebook at: http://www.facebook.com/marscuriosity and on Twitter at: http://www.twitter.com/marscuriosity.

Images (mentioned), Video (mentioned), Text, Credits: NASA / Dwayne Brown / JPL / Guy Webster.

Cheers, Orbiter.ch

Hubble Sees a Dwarf Galaxy Shaped by a Grand Design

ESA - Hubble Space Telescope patch.

June 23, 2014

The subject of this Hubble image is NGC 5474, a dwarf galaxy located 21 million light-years away in the constellation of Ursa Major (The Great Bear). This beautiful image was taken with Hubble's Advanced Camera for Surveys (ACS).

The term "dwarf galaxy" may sound diminutive, but don't let that fool you — NGC 5474 contains several billion stars! However, when compared to the Milky Way with its hundreds of billions of stars, NGC 5474 does indeed seem relatively small.

NGC 5474 itself is part of the Messier 101 Group. The brightest galaxy within this group is the well-known spiral Pinwheel Galaxy (also known as Messier 101). This galaxy's prominent, well-defined arms classify it as a "grand design galaxy," along with other spirals Messier 81 and Messier 74.

Hubble orbiting the Earth

Also within this group are Messier 101's galactic neighbors. It is possible that gravitational interactions with these companion galaxies have had some influence on providing Messier 101 with its striking shape. Similar interactions with Messier 101 may have caused the distortions visible in NGC 5474.

Both the Messier 101 Group and our own Local Group reside within the Virgo Supercluster, making NGC 5474 something of a neighbor in galactic terms.

For images and more information about Hubble, visit: http://www.nasa.gov/hubble and http://www.spacetelescope.org/

Image, Video, Text, Credits: ESA / NASA.

Greetings, Orbiter.ch

From oldest to youngest: a line of star nurseries

ESA - Herschel Mission patch.

June 23, 2014

Star-forming regions in the molecular cloud W48

Just as children are sorted into age groups at school, so the seeds of new stars can also be found in ‘classes’ of others of similar ages. This is especially true when the birth of stars in a cloud of gas and dust is triggered by an external event, like the explosion of a nearby supernova.

This image from ESA’s Herschel space observatory shows a sequence of star-forming regions in the molecular cloud W48, some 10 000 light-years away in the constellation Aquila (the Eagle).

The blue, jellyfish-shaped cloud at the lower left is the oldest stellar nursery in the image. Young and massive stars embedded within it have shaped it into a bubble and heated the diffuse gas, making it shine at the longest wavelengths probed by Herschel.

To its right, another glowing cloud conceals clumps that will evolve into massive stars. These clumps, some of which are visible as bright blotches of light, are also lined up by their age: the older ones at the lower-left and the younger ones to the upper-right. The youngest in this sequence is the small cyan lump at the centre of the image, harbouring the seeds of future massive stars.

Astronomers believe that this sequence of stellar birth is the result of dozens of supernovas that exploded over 10 million years ago in a region called Aquila Supershell, beyond the left edge of this image. Compressing the surrounding material, these supernovas may have initiated a wave of star formation that sparked, one by one, these stellar cribs.

Herschel space observatory

The image is a composite of the wavelengths of 70 microns (blue), 160 microns (green) and 250 microns (red) and spans about one degree on the long side. North is to the upper-left and east is to the lower left. The data were acquired with Herschel’s PACS and SPIRE instruments in September 2010, as part of a larger map of the W48 molecular complex in the HOBYS Key Programme. This was first published in a paper by Q. Nguyen Luong, et al. 2011. A more detailed study of the star-forming regions shown in this image is presented in a paper by K.L.J. Rygl, et al. 2014.

For more information about Herschel, visit: http://www.esa.int/Our_Activities/Space_Science/Herschel

Images, Text, Credits: ESA/Herschel/PACS/SPIRE/HOBYS Key Programme consortium.

Best regards, Orbiter.ch

QuikScat's Eye on Ocean Winds Lives On with RapidScat

NASA - QuikScat Mission patch.

June 20, 2014

Image above: Using data from NASA’s QuikScat, weather forecasters were able to predict hazardous weather events over oceans 6 to 12 hours earlier than before these data were available. Orange areas show where winds are blowing the hardest and blue shows relatively light winds. Image Credit: NASA.

Today (June 19) marks the 15th anniversary of the launch of NASA's QuikScat, a satellite sent for a three-year mission in 1999 that continues collecting data. Built in less than 12 months, QuikScat has watched ocean wind patterns for 15 years and improved weather forecasting worldwide. Despite a partial instrument failure in 2009, it provides calibration data to international partners.

On this anniversary, the mission's team is preparing to calibrate ISS-RapidScat, the successor that will maintain QuikScat’s unbroken data record. After its launch in a few months, RapidScat will watch ocean winds from the International Space Station (ISS) for a two-year mission.

Much like QuikScat, ISS-RapidScat was built in less than two years and at a fraction of its predecessor’s budget. Both missions are testaments to ingenuity, craftsmanship and speedy construction in the name of improving our understanding of Earth’s winds.

“Both ISS-RapidScat and QuikScat came about to react quickly to the failure of another spaceborne instrument,” said Ernesto Rodriguez, project scientist for the ISS-RapidScat mission at NASA’s Jet Propulsion Laboratory, Pasadena, California. “What differentiates these missions is cost and risk: RapidScat had to be built with a fraction of the QuikScat budget, and the mission accepted a much riskier approach,” Rodriguez said. RapidScat was constructed primarily from QuikScat’s spare parts and will be the first scatterometer to berth on the International Space Station.

Scatterometers help scientists estimate the speed and direction of winds at the ocean’s surface by sending microwave pulses to Earth’s surface. Strong waves or ripples scatter the microwaves, sending some of them back toward the scatterometer. Based on the strength of this backscatter, scientists can estimate the strength and direction of the wind at the ocean’s surface.

Scatterometer data are critical for observing global weather patterns. They also help ocean fishermen decide where to fish, ship captains choose shipping lanes and researchers track hurricanes, cyclones and El Niños.

“The usefulness of this wind measurement is enormous,” said JPL’s Jim Graf, who served as project manager for the QuikScat mission in the 1990s and is now the deputy director of JPL’s Earth Science and Technology Directorate. “One of the dominant factors in understanding the climate is to assess what is happening in the ocean circulation. And one of the dominant factors in ocean circulation is the wind at the surface, which is what scatterometers measure.”

Image above: QuikScat could detect differences in average wave height much smaller than inch (a centimeter) during its 15 years watching ocean winds. Image Credit: Wikimedia Commons.

NASA launched its first scatterometer satellite in 1978 and its second instrument, the NASA Scatterometer (NSCAT), on a Japanese satellite in 1996. Each lasted less than a year, but collected hundreds of times more data about ocean winds than ships or buoys and improved weather forecasts from the National Oceanic and Atmospheric Administration (NOAA).

But the spacecraft carrying NSCAT malfunctioned in 1997. Immediately, a team of JPL scientists and engineers raced to get a scatterometer satellite back into space.

“We had the idea that a partially developed spacecraft bus could be mated with an advanced version of the instrument that was already under development, and we could get something up quickly. So we went to NASA, and they said, ‘Okay, let’s give it a shot, but we want you to be ready to go one year from the go-ahead,’” Graf said. “And so we took off running, and we didn’t stop for a whole year.”

In that year, Ball Aerospace & Technologies Corp., Boulder, Colorado, built the QuikScat satellite bus while JPL finished the new SeaWinds scatterometer instrument. It launched in 1999. For the next decade, QuikScat made about 400,000 daily measurements of wind speed and direction. Over 15-mile (25-kilometer) segments of ocean, its measurements were detailed enough to estimate average wind speed within 6 feet (2 meters) per second.

The SeaWinds instrument on QuikScat used a rotating antenna to measure a swath of Earth’s surface 1,118 miles (1,800 kilometers) wide -- about the distance from Los Angeles to Seattle. As QuikScat flew, the rotations overlapped to cover more than 90 percent of Earth’s surface every day.

But by the end of 2009, long after the expected end of QuikScat’s mission, the lubricant coating the antenna’s bearings dried up. Instead of tracing a round swath on Earth’s surface, it pointed straight down and only watched the waves directly below it. Still, those data were sufficient to help calibrate newer satellites.

QuikScat satellite. Image Credit: NASA

“Since 2009, we’ve been able to keep QuikScat operating quite successfully,” said QuikScat Project Manager Rob Gaston of JPL. “We used QuikScat’s highly successful backscatter measurements, which were well understood and had demonstrated stability, as a calibration standard for many instruments, including other scatterometers.” The European Space Agency and Indian Space Research Organization have both used QuikScat data to calibrate scatterometers in the last five years.

QuikScat’s final task will be to calibrate its successor, RapidScat. The satellite will continue collecting data until April 2015, when it will be decommissioned after nearly 16 years in orbit.

RapidScat, like QuikScat, was built in a fraction of the timeline for most missions. The two missions even share hardware: JPL engineers used SeaWinds test parts to build much of RapidScat, which also uses a rotating dish antenna.

RapidScat will launch aboard a SpaceX Dragon resupply mission this summer. Flying in the space station’s orbit means RapidScat will spend more time observing Earth's tropics than previous scatterometer satellites, which orbited farther north and south.

“RapidScat will be able to, for the first time, map the evolution of winds as the day progresses, which is important for understanding how clouds and precipitation develop, especially in the tropics, which are key regions in Earth's climate system,” Rodriguez said. “It will provide a common reference to tie all of these measurements together.”

Together with scatterometers managed by India and Europe, RapidScat will maintain the continuous climate record QuikScat began while adding its own unique perspective from orbit.

For more information about ISS-RapidScat, visit: http://winds.jpl.nasa.gov/missions/RapidScat/

For more information about QuikScat, visit: http://winds.jpl.nasa.gov/missions/quikscat/

NASA monitors Earth's vital signs from land, air and space 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 in 2014, visit: http://www.nasa.gov/earthrightnow

Images (mentioned), Text, Credits: NASA.

Greetings, Orbiter.ch

Science and spacewalks on Space Station

ESA - Blue Dot Mission patch.

20 June 2014

Flying over Earth

Three weeks into ESA astronaut Alexander Gerst’s Blue Dot mission on the International Space Station and the new arrival is now spending more time on scientific research in the microgravity laboratory.

Alexander has worked on controlled fires in space and continuously monitored his sleep patterns, at the same time as making sure the orbital outpost is working at full capacity.

Apart from continuing the long-term studies on eyes and headaches in space, Alexander recorded his temperature and hormones over 36 hours to understand his sleep patterns.

Columbus laboratory

Astronauts on the Station witness 16 sunrises and sunsets each day – whereas on Earth our bodies rely on sunlight to kick-start hormone production that make us sleepy or wake us up.

Researchers are interested to see how the unique 90-minute days influence sleep. Aside from making sure astronauts feel awake at critical moments, this research in space allows sleep specialists to test theories that they couldn’t anywhere else.

Alexander acted as a weightless firestarter and firefighter this week when he ignited small samples of fuels safely contained in ESA’s glovebox to see how they burn in space. He volunteered as a fireman before becoming an astronaut, so the experiment was in good hands.

This research will improve computer models for fire detectors and extinguishers, both in space and on Earth. He explained the experiment via Twitter: “Burning things in space for better fire safety on Earth.”

Burning fuel in space

Elsewhere, Alexander took samples of his blood and saliva and collected data on his eyes, his skin and his body so researchers can understand how astronauts react to weightlessness.

Other notable experiments included the harvesting of space-grown salads – unfortunately for the astronauts, they are not allowed to eat them.

Spacewalk

Yesterday, cosmonauts Oleg Armetyev and Alexander Skvortsov spent over six hours working outside the Station to install an antenna, take samples and move experiments. Meanwhile the four astronauts inside continued their science activities.

Checking spacesuit

Earlier, Alexander thoroughly checked a newly arrived US spacesuit. Before being declared ready for use, he had to make sure it had survived its climb into space.

Spacewalk

Image above: Russian cosmonauts Alexander Skvortzov and Oleg Artemyev spent over six hours working outside the International Space Station on 19 June 2014. This picture was taken by ESA astronaut Alexander Gerst from inside the orbital outpost.

Alexander even had time this week for educational activities for Earth Guardian, inspiring children to observe geographical features such as oceans, rivers, landscapes, mountains and forests in their areas during the summer holidays.

Related links:

All about Blue Dot: http://www.esa.int/Our_Activities/Human_Spaceflight/Blue_dot

Connect with Alexander Gerst: http://alexandergerst.esa.int/

Where is the International Space Station?: http://www.esa.int/Our_Activities/Human_Spaceflight/International_Space_Station/Where_is_the_International_Space_Station

Images, Text, Credits: ESA / NASA.

Greetings, Orbiter.ch

Beautiful Brazil

ESA - Proba-V Mission logo.

20/06/2014

Proba-V imaging Brazil

As football fans worldwide keep their eyes trained on Brazil, ESA’s Proba-V minisatellite captures the entire country in a single image.

The Andean Plateau, or Altiplano, of neighbouring Bolivia, including Lake Titicaca and the giant Salar Uyuni salt flat, are visible towards the scene’s western edge.

Proba is smaller than a cubic metre but its view spans a mighty 2250 km. It reveals details 300 m across but the central part of the image is sharper – down to 100 m – as demonstrated in the right-hand image, which shows a detail of the River Negro joining the mighty River Amazon.

Proba-V is a miniaturised ESA satellite tasked with a full-scale mission: to map land cover and vegetation growth across the entire planet every two days.

Artist's view of the Proba-V satellite

The camera’s continent-spanning field of view collects light in the blue, red, near-infrared and mid-infrared wavebands, ideal for monitoring plant and forest growth as well as inland water bodies.

Proba’s images are processed and distributed to hundreds of scientific end users by VITO, Belgium’s Flemish Institute for Technological Research, extending the coverage of previous generations of the Vegetation camera flown on the Spot-4 and Spot-5 satellites.

For more information about Proba-V, visit: http://www.esa.int/Our_Activities/Technology/Proba_Missions

Images, Text, Credits: ESA / BELSPO.

Cheers, Orbiter.ch