The orbit of the ISS will raise by Edoardo Amaldi (ATV-3)

ESA - ATV-3 "Edoardo Amaldi" patch.

31/03/2012

April 1 in accordance with the program to ensure the ballistic flight of the International Space Station is scheduled test correction of its orbit. The planned operation is carried out in order to verify the functionality of the ISS cargo spacecraft ATV-3 ("Edoardo Amaldi"), docked to the station on March 29.

ATV-3 boost ISS orbit

The maneuver will be performed using the two main engines of European truck. Maintaining the desired spatial position of the ISS at the time of the correction will be provided orientation engines of the Russian Service Module "Zvezda" and the cargo ship "Progress M-14M."

ATV / Soyuz-TMA / Progress-M / HTV size's comparative

According to the ballistic Service Mission Control Center Engineering Research Institute engines will be included in 1:00 and 54 minutes Moscow Time (March 31 at 21:54 GMT) and have worked for 411 seconds. As a result, the ISS will receive an additional boost of 1 meter per second. The average height of its orbit will increase by 1.7 kilometers and will be 389.8 kilometers.

For more Information about ISS, visit: http://www.esa.int/esaHS/iss.html and http://www.nasa.gov/mission_pages/station/main/index.html

Images, Text, Credits: Press-service of Federal Space Agency (Roscosmos) and the PCO / ESA / Orbiter.ch / Translation: Orbiter.ch.

Cheers, Orbiter.ch

Space Station Keeps Watch on World's Sea Traffic

ISS - International Space Station patch.

March 31. 2012

As the International Space Station circles Earth, it has been tracking individual ships crossing the seas beneath. An investigation hosted by the European Space Agency (ESA) in its Columbus module has been testing the viability of monitoring global maritime traffic from the station's orbit hundreds of miles (kilometers) above since June 2010.

The ship-detection system being tested is based on the Automatic Identification System, or AIS, the marine equivalent of the air traffic control system.

Image above: The International Space Station as seen from the departing Atlantis space shuttle, May 23, 2010. (NASA).

All international vessels, cargo ships above certain weights and passenger carriers of all sizes must carry "Class A" AIS transponders, broadcasting continually updated data, such as identity, position, course, speed, ship particulars, cargo and voyage information to and from other vessels and shore.

AIS allows port authorities and coast guards to track seagoing traffic, but the system relies on VHF radio signals with a horizontal range of just 40 nautical miles (74 km). This makes it useful within coastal zones and on a ship-to-ship basis, but not in the open ocean; ocean traffic was largely untracked. However, AIS signals travel much further vertically, making the space station an ideal location for space-based AIS signal reception and, therefore, providing the capability of tracking global maritime traffic from space.

Image above: The International Space Station makes 15 orbits around the Earth each day. The illustration of the COLAIS system in operation using the NORAIS receiver shows the station passing the Mediterranean. Its field of view is shown in red; detected vessels are shown as ship symbols, and terrestrial AIS base stations are shown as buildings. The data are for the first five hours of June 3, 2010. (FFI).

Astronauts were instrumental in enabling the COLAIS experiment, which is an in-orbit demonstration project of ESA's General Support Technology Program. Columbus was not originally outfitted with VHF antennas to capture the AIS signals; they were installed on the outside of the module during a spacewalk in November 2009, with the remaining piece of hardware, the ERNO-Box control computer, installed inside Columbus along with the NORAIS receiver in May 2010. The ERNO-Box is itself an orbital demonstration of a new class of space computer developed by Astrium Gmbh, Germany. Astrium was responsible for overall system integration, and contributed the ERNO-Box and a grappling adaptor, or GATOR, used to attach the AIS antenna to Columbus. Antennas were built by AMSAT.

Image above: Astronaut Randolph Bresnik seen during Atlantis EVA-2 on November 21, 2009, with the unfurled AIS antenna, attached to Columbus for use in experimental tracking of VHF signals of ships at sea. (NASA).

Global Overview of Maritime Traffic

The AIS ground coverage from the station is between approximately 68° north and 68° south. The system consists of two antenna assemblies that were mounted on the outside of Columbus during a spacewalk in November 2009 as well as data relay hardware (the ERNO-Box) and a receiver mounted inside Columbus. The two operational phases with the first receiver from Norway,or NORAIS, which is operated by FFI/Norway, have been extremely successful, with data telemetry received by the Norwegian User Support and Operation Center, or N-USOC, in Trondheim, Norway, via ESA's Columbus Control Center in Germany. Data has been received by NORAIS in almost continuous operation, and all modes of operation have worked extremely well. The NORAIS Receiver has a sample mode that can collect the raw signal, digitize it and send it to ground for analysis of signal quality, which is proving very helpful in making additional improvements/ refinements to the system in extremely crowded shipping areas where the possibility of lost signals or mixed signals can occur.

This is used both to investigate the signal environment and to evaluate the performance of new receiver technologies on the ground. Several hundred data sets have been collected and processed with new candidate algorithms for next generation receivers.

Image above: The spectrum versus time for 22 seconds of a sampled data. The messages can be seen as vertical lines. Approximately 150 messages are decoded from the data. (FFI).

The results of the analyses have been very good. On a good day, approximately 400,000 ship position reports are received from more than 22,000 different ship identification numbers (Maritime Mobile Service Identity, or MMSI). In a summary made in Oct. 2011, the total number of position reports received exceeded 110 million messages from more than 82,000 different MMSI numbers.

As an addition to the original technical topics, operational experimentation has been included in the investigations. Near-real-time data transfer is crucial to meet the requirement of SAT-AIS set by ESA in cooperation with operational users. After an upgrade of the ground systems in the N-USOC, 10 days of near-real-time data show that 80 percent of the messages collected in the period could be delivered through the station's communications network with data latency significantly less than 1 hour. The near-real-time data delivery has been part of routine operations since Nov. 2011.

At present, a new version of the decoder algorithm, developed by Kongsberg Seatex as part of the technology development contract with ESA, is being tested. The development benefits from the investigations of the sampled data and ongoing work in other ESA projects. The firmware was uploaded to the NORAIS Receiver through the station's communications network and verified and activated in Jan. 2011. The preliminary results indicate that the performance in terms of decoded messages has increased by a factor of between 1.5 and 2.0 for the high traffic zones that ESA has specified should be monitored with high performance.

Image above: Ship position reports received with the NORAIS Receiver during 24 hours, 29th June 2010. (FFI).

The work on better algorithms continues. A second NORAIS Receiver upgrade is planned in May 2012. The results of the development will support the design and development of a space-based AIS system in general as well as the performance of the AIS receiver on the station.

Integrating AIS information with other satellite data, such as information from remote-sensing satellites, should significantly improve maritime surveillance and boost safety and security at sea. The payload designed for the Norwegian AISSat-1 satellite, which launched into a near polar orbit in July 2010, provides similarly good data in the high north. The NORAIS Receiver is software-defined radio design operating across the maritime band from 156 to 163 megahertz. The tuning of the NORAIS receiver to frequencies under consideration for allocation to space-based AIS has been carried out, and NORAIS took part in international tests of these two proposed frequencies in October 2010 as arranged by U.S. Coast Guard.

The main reason for covering more than the two current frequencies in use for AIS is to have the possibility to demonstrate the operational use of new channels in the maritime band being allocated to space-based AIS. Also, this configuration allows for characterization of the maritime VHF spectrum with respect to occupancy and interference. The software implementation allows for optimization of the receiver settings in orbit and also allows for upload of new signal processing algorithms.

The Vessel Identification System, or VIS, could potentially be beneficial to many European entities, particularly in assisting them in law enforcement, fishery control campaigns, maritime border control, maritime safety and security issues, including marine pollution surveys, search and rescue and anti-piracy. Various service entities have already been asking to get access to the VIS data, which is continuously acquired on Columbus.

For more Information about ISS, visit: http://www.esa.int/esaHS/iss.html and http://www.nasa.gov/mission_pages/station/main/index.html

Images, Text, Credit: NASA / FFI / European Space Agency (ESA).

Best regards, Orbiter.ch

From Baikonur cosmodrome launch space rocket Proton-K

Khrunichev State Research and Production Space Center logo.

30/03/2012

March 30 at 9:00. 49 minutes. GMT from the Baikonur Cosmodrome calculations of enterprises and organizations of missile and space industry, the launch of a space rocket "Proton-K" with the spacecraft "Cosmos" series for the Ministry of Defence of the Russian Federation.

In accordance with cyclogram flight spacecraft launched into the desired orbit.

Proton-K launch

It was the 310th launch of the carrier for the 45-year history of operation. To launch the spacecraft into an orbit used by D-stage.

Launch vehicle "Proton-K" refers to the heavy class. It was developed in the branch N 1 CDB Engineering (now the Bureau "Sayut" - Khrunichev them. Khrunichev) under the leadership of Chelomei on the basis of a two-stage vehicle UR-500.

The first launch (in the two-stage version) was held July 16, 1965 with the withdrawal of the low earth orbit scientific satellite "Proton", whose name was assigned to the booster. After the first four launches of "Proton" (in the two-stage version), it was decided to establish on the basis of its rocket launch mass with an increase to 700 tons.

Proton-K launch

Since 1967, began launches missile in the three-and four-ways. The first three-stage missile with a UR-500K booster block D started on March 10, 1967 with the satellite "Cosmos-146". This date is considered the birthday of "Proton-K". A three-step "Proton-K" was used for payload into low orbit, a four - to launch spacecraft into orbits of high energy (including the GTO, GEO and escape trajectories).

In 1978, the carrier rocket "Proton-K" with the technical and launch complexes was accepted into serial production. In the creation of space rocket "Proton" involving hundreds of enterprises and factories.

Since 1967, "Proton-K" orbited around 50 types of spacecraft. Among them, the spacecraft "Cosmos" series, "Screen", "Rainbow," "Horizon," apparatus for the study of the Moon, Mars, Venus and Halley's Comet.

Proton-K delivered to orbit the world's first long-term orbital station "Salyut-1" and all subsequent stations in this series, the DOS "Diamond", all the modules for the first space station "Mir", made in Russia modules "Dawn" and " Star" for the International Space Station, as well as heavy spacecraft communications.

Spacecraft running "Proton-K", carried out a range of programs of national economic, scientific and defense purposes. Launched a single satellite system based on satellites "Rainbow", "Display", "Horizon," "Express."

It is the "Proton-K" was used extensively to derive the orbit of spacecraft global navigation satellite system GLONASS.

Due to the unique performance characteristics, high coefficient of reliability and profitability, "Proton-K" was the first Russian carrier rocket, which has attracted the attention of foreign customers.

The first commercial launch of "Proton-K" took place on April 9, 1996 with the European geostationary communication satellite Astra 1F. There were carried out 32 commercial launches, "Proton-K". The last commercial launch using the "Proton-K" was held June 6, 2003 with the satellite AMC-9.

Original text in Russian: http://www.federalspace.ru/main.php?id=2&nid=18875

Images, Text, Credits: Press and Information Office and the Khrunichev Space Agency them. Khrunichev / Roscosmos / Translation: Orbiter.ch.

Greetings, Orbiter.ch

Hubble Spies a Spiral Galaxy Edge-on

NASA - Hubble Space Telescope patch.

March 30, 2012

The NASA/ESA Hubble Space Telescope has spotted the "UFO Galaxy." NGC 2683 is a spiral galaxy seen almost edge-on, giving it the shape of a classic science fiction spaceship. This is why the astronomers at the Astronaut Memorial Planetarium and Observatory, Cocoa, Fla., gave it this attention-grabbing nickname.

While a bird's eye view lets us see the detailed structure of a galaxy (such as this Hubble image of a barred spiral), a side-on view has its own perks. In particular, it gives astronomers a great opportunity to see the delicate dusty lanes of the spiral arms silhouetted against the golden haze of the galaxy’s core. In addition, brilliant clusters of young blue stars shine scattered throughout the disc, mapping the galaxy’s star-forming regions.

Perhaps surprisingly, side-on views of galaxies like this one do not prevent astronomers from deducing their structures. Studies of the properties of the light coming from NGC 2683 suggest that this is a barred spiral galaxy, even though the angle we see it at does not let us see this directly.

This image is produced from two adjacent fields observed in visible and infrared light by Hubble’s Advanced Camera for Surveys. A narrow strip which appears slightly blurred and crosses most the image horizontally is a result of a gap between Hubble’s detectors. This strip has been patched using images from observations of the galaxy made by ground-based telescopes, which show significantly less detail. The field of view is approximately 6.5 by 3.3 arcminutes.

For more information about Hubble Space Telescope, visit: http://www.nasa.gov/mission_pages/hubble/main/index.html and http://www.spacetelescope.org/

Image, Text, Credit: ESA / Hubble & NASA.

Greetings, Orbiter.ch

Getting to the Moon on Drops of Fuel

Aerospace Engineering.

March 30, 2012

 EPFL - A Couple Drops of Fuel to Get to the Moon with MicroThrust

The first prototype of a new, ultra-compact motor that will allow small satellites to journey beyond Earth’s orbit is just making its way out of the EPFL laboratories where it was built. The goal of the micro motor: to drastically reduce the cost of space exploration.

Imagine reaching the Moon using just a tenth of a liter of fuel. With their ionic motor, MicroThrust, EPFL scientists and their European partners are making this a reality and ushering in a new era of low-cost space exploration. The complete thruster weighs just a few hundred grams and is specifically designed to propel small (1-100 kg) satellites, which it enables to change orbit around the Earth and even voyage to more distant destinations – functions typically possible only for large, expensive spacecraft. The just-released prototype is to be employed on CleanSpace One, a satellite under development at EPFL that is designed to clean up space debris, and on OLFAR, a swarm of Dutch nanosatellites that will record ultra-low radio-frequency signals on the far side of the Moon.

MicroThrust implementation on a cube satellite

The motor, designed to be mounted on satellites as small as 10x10x10 cm3, is extremely compact but highly efficient. The prototype weighs only about 200 grams, including the fuel and control electronics.

“At the moment, nanosatellites are stuck in their orbits. Our goal is to set them free,” explains Herbert Shea, coordinator of the European MicroThrust project and director of EPFL’s Microsystems for Space Technologies Laboratory.

Small satellites are all the rage right now because their manufacturing and launch costs are relatively low – about half a million dollars, compared to conventional satellites that run into the hundreds of millions. But nanosatellites currently lack an efficient propulsion system that would render them truly autonomous and thus able to carry out exploration or observation missions.

A motor that doesn’t burn fuel

Instead of a combustible fuel, the new mini motor runs on an “ionic” liquid, in this case the chemical compound EMI-BF4, which is used as a solvent and an electrolyte. It is composed of electrically charged molecules (like ordinary table salt) called ions, except that this compound is liquid at room temperature. The ions are extracted from the liquid and then ejected by means of an electric field to generate thrust. This is the principle behind the ionic motor: fuel is not burned, it is expelled.

MicroThrust description

In the motor developed at EPFL, the flow of ions is emitted from an array of tiny silicon nozzles – over 1,000 per square centimeter. The fuel is first guided by capillary action from a reservoir to the extremity of the micro-nozzles, where the ions are then extracted by an electrode held at 1,000 volts, accelerated, and finally emitted out the back of the satellite. The polarity of the electric field is reversed every second, so that all the ions – positive and negative – are ejected.

SystematIC Design, a MicroThrust project partner, designed the motor’s electrical system. The ion ejection system requires a high electrical voltage, but the available energy aboard a 1-liter nanosatellite is limited to a few small solar cells – in practice, about four watts of power. The Dutch company was able to develop a system that overcame this difficulty.

Cruising speed: 40,000 km per hour

After six months of acceleration, the microsatellite’s speed increases from 24,000 km/h, its launch speed, to 42,000 km/h. The acceleration is only about a tenth of a millimeter per square second, which translates into 0-100 km/h in 77 hours. But in space, where there is no friction to impede motion, gentle but steady acceleration is the way to go.

“We calculated that in order to reach lunar orbit, a 1-kg nanosatellite with our motor would travel for about six months and consume 100 milliliters of fuel,” explains Muriel Richard, a scientist in EPFL’s Swiss Space Center.

The ionic motor will power CleanSpace One – a nanosatellite whose mission is to tidy up space by grabbing space debris and pulling it into the Earth’s atmosphere to be safely incinerated. According to the Swiss Space Center, CleanSpace One will take two to three months and more than 1,000 terrestrial revolutions to reach one of its targets, the decommissioned Swisscube cubesat or Tlsat-1 cubesat. Scientists have just over a year to finalize their system.

MicroThrust

Researchers have a bit more than a year to finalize the ionic motor. The prototype was developed in the context of a European project coordinated by EPFL and involved Queen Mary and Westfield College in the UK, the Dutch companies TNO and SystematIC Design B.V., and Nanospace AB in Sweden.

For more information about EPFL, visit: http://www.epfl.ch/

Images, Video, Text, Credit: Ecole Polytechnique Fédérale de Lausanne (EPFL).

Best regards, Orbiter.ch

A Star Explodes, Turns Inside-Out

NASA - Chandra X-ray Observatory patch.

March 30, 2012

A new X-ray study of the remains of an exploded star indicates that the supernova that disrupted the massive star may have turned it inside out in the process. Using very long observations of Cassiopeia A (or Cas A), a team of scientists has mapped the distribution of elements in the supernova remnant in unprecedented detail. This information shows where the different layers of the pre-supernova star are located three hundred years after the explosion, and provides insight into the nature of the supernova.

An artist's illustration on the left shows a simplified picture of the inner layers of the star that formed Cas A just before it exploded, with the predominant concentrations of different elements represented by different colors: iron in the core (blue), overlaid by sulfur and silicon (green), then magnesium, neon and oxygen (red). The image from NASA's Chandra X-ray Observatory on the right uses the same color scheme to show the distribution of iron, sulfur and magnesium in the supernova remnant. The data show that the distributions of sulfur and silicon are similar, as are the distributions of magnesium and neon. Oxygen, which according to theoretical models is the most abundant element in the remnant, is difficult to detect because the X-ray emission characteristic of oxygen ions is strongly absorbed by gas in along the line of sight to Cas A, and because almost all the oxygen ions have had all their electrons stripped away.

A comparison of the illustration and the Chandra element map shows clearly that most of the iron, which according to theoretical models of the pre-supernova was originally on the inside of the star, is now located near the outer edges of the remnant. Surprisingly, there is no evidence from X-ray (Chandra) or infrared (Spitzer Space Telescope) observations for iron near the center of the remnant, where it was formed. Also, much of the silicon and sulfur, as well as the magnesium, is now found toward the outer edges of the still-expanding debris. The distribution of the elements indicates that a strong instability in the explosion process somehow turned the star inside out.

The Elements of Supernova Cas A

This Chandra X-ray video shows the elements distribution in supernova remnant Cas A. The distributions of sulfur, silicon, magnesium and neon are similar. Oxygen, which according to theoretical models is the most abundant element in the remnant, is difficult to detect because the X-ray emission characteristic of oxygen ions is strongly absorbed by gas in along the line of sight to Cas A, and because almost all the oxygen ions have had all their electrons stripped away. (NASA/CXC/A. Hobart).

This latest work, which builds on earlier Chandra observations, represents the most detailed study ever made of X-ray emitting debris in Cas A, or any other supernova remnant resulting from the explosion of a massive star. It is based on a million seconds of Chandra observing time. Tallying up what they see in the Chandra data, astronomers estimate that the total amount of X-ray emitting debris has a mass just over three times that of the Sun. This debris was found to contain about 0.13 times the mass of the Sun in iron, 0.03 in sulfur and only 0.01 in magnesium.

The researchers found clumps of almost pure iron, indicating that this material must have been produced by nuclear reactions near the center of the pre-supernova star, where the neutron star was formed. That such pure iron should exist was anticipated because another signature of this type of nuclear reaction is the formation of the radioactive nucleus titanium-44, or Ti-44. Emission from Ti-44, which is unstable with a half-life of 63 years, has been detected in Cas A with several high-energy observatories including the Compton Gamma Ray Observatory, BeppoSAX, and the International Gamma-Ray Astrophysics Laboratory (INTEGRAL).

These results appeared in the February 20th issue of The Astrophysical Journal in a paper by Una Hwang of Goddard Space Flight Center and Johns Hopkins University, and (John) Martin Laming of the Naval Research Laboratory.

Read more/access all images: http://chandra.harvard.edu/photo/2012/casa/

Text, Video (mentioned), Credits: Illustration: NASA / CXC / M.Weiss; Image: NASA / CXC / GSFC / U. Hwang & J. Laming.

Greetings, Orbiter.ch

Enceladus plumes and Dione

NASA / ESA - Cassini "Insider's" logo.

29 March 2012

 Enceladus plumes

The international Cassini spacecraft was on its way to its lowest pass yet over the south polar region of Saturn’s moon Enceladus when it took this image of the impressive plumes.

The plumes are jets of water ice and vapour, mixed with organic compounds. With this flyby coming within a mere 74 km, scientists hope to learn more about the composition, density and variability of these remarkable features of Enceladus. 

Saturn’s moon Dione

A day after the flyby, Cassini imaged Dione, another of Saturn’s moons. From a distance of 44 000 km, features like impact craters are clearly visible on the side of the moon that faces away from the Sun.

Notes for Editors:

The Cassini–Huygens mission is a cooperative project between NASA, ESA and the Italian space agency, ASI. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, DC, USA. The Cassini orbiter and its two cameras were designed, developed and assembled at JPL. The imaging operations centre is based at the Space Science Institute in Boulder, Colorado.

Related Links:

At Saturn and Titan: http://www.esa.int/SPECIALS/Cassini-Huygens/index.html

NASA website: http://www.nasa.gov/mission_pages/cassini/main/index.html

Images, Text, Credits: NASA / JPL / Space Science Institute.

Cheers, Orbiter.ch

The mission of ATV-3: "Edoardo Amaldi" final rendezvous and docking maneuver with the ISS

ESA - ATV-3 "Edoardo Amaldi" Mission patch.

28/03/2012

Automated Transfer Vehicle ATV-3, launched March 23 from the Guiana Space Centre, close to its ultimate goal - the International Space Station (ISS).

ATV3 is on track to dock with the ISS

Flight of the truck from the European launch and before docking with the Russian module "Zvezda" clock controlled by the ISS mission control specialist centers in the Moscow suburb of Korolev, Toulouse (France) and Houston (USA).

ATV-3 docking on ISS

Cosmonaut Oleg Kononenko and the Russian Space Agency ESA astronaut Andre Cowper from the ISS, carrying at the moment space watch on board the orbital station, will also oversee the operations of docking to provide a high level of accuracy required at all stages of convergence ATV / Russian module "Zvezda".

Oleg Kononenko and Andre Cowper: training with ATV-3 docking with the ISS

After docking and connection of all the crew interfaces can open the hatch and enter in a sealed compartment ATV. Since then, Andre Cowper will be responsible for logistical operations on a ship.

Joining the European space truck with the ISS is docked at 02.34 GMT on March 29.

The ISS crew is working 30/31-y long expedition in the Commander Daniel Burbank (NASA), flight engineers Anton Shkaplerova (Roscosmos), Anatoly Ivanishin (Roscosmos), Oleg Kononenko (Roscosmos), Andre Cowper (ESA) and Donald Pettit (NASA) .

Image, Text, Videos, Credits: Press Service of the Russian Space Agency (Roscosmos PAO) / NASA TV / ESA / Translation: Orbiter.ch.

Greetings, Orbiter.ch

'Mount Sharp' On Mars Links Geology's Past and Future

NASA - Mars Science Laboratory (MSL) patch.

03.28.12

Curiosity, the big rover of NASA's Mars Science Laboratory mission, will land in August 2012 near the foot of a mountain inside Gale Crater. Image credit: NASA / JPL-Caltech / ESA / DLR / FU Berlin / MSSS.

One particular mountain on Mars, bigger than Colorado's grandest, has been beckoning would-be explorers since it was first sighted from orbit in the 1970s. Scientists have ideas about how it took shape in the middle of ancient Gale Crater and hopes for what evidence it could yield about whether conditions on Mars have favored life.

No mission to Mars dared approach it, though, until NASA's Mars Science Laboratory mission, which this August will attempt to place its one-ton rover, Curiosity, at the foot of the mountain. The moat of flatter ground between the mountain and the crater rim encircling it makes too small a touchdown target to have been considered safe without precision-landing innovations used by this mission.

This illustration shows the size of Mount Sharp in comparison to three large mountains on Earth. Image credit: NASA / JPL-Caltech / MSSS.

To focus discussions about how Curiosity will explore the mountain during a two-year prime mission after landing, the mission's international Project Science Group has decided to call it Mount Sharp. This informal naming pays tribute to geologist Robert P. Sharp (1911-2004), a founder of planetary science, influential teacher of many current leaders in the field, and team member for NASA's first few Mars missions. Sharp taught geology at the California Institute of Technology (Caltech), in Pasadena, from 1948 until past his retirement. Life magazine named him one of the 10 best college teachers in the nation.

"Bob Sharp was one of the best field geologists this country has ever had," said Michael Malin, of Malin Space Science Systems, San Diego, principal investigator for two of Curiosity's 10 science instruments and a former student of Sharp's.

"We don't really know the origins of Mount Sharp, but we have plans for how to go there and test our theories about it, and that's just how Bob would have wanted it," Malin said.

This image shows the target landing area for Curiosity, the rover of NASA's Mars Science Laboratory mission. Image credit: NASA / JPL-Caltech / ESA / DLR / FU Berlin / MSSS.

Caltech Provost Edward Stolper, former chief scientist for the Mars Science Laboratory, said, "For much of his more than 50 years at Caltech, Bob Sharp was the central figure in its programs in the geological and planetary sciences. One of his major contributions was the building of a program in planetary sciences firmly rooted in the principles and approaches of the geological sciences.

"Moreover, through his own work on the Jet Propulsion Laboratory's early missions to Mars and the work of others that he influenced, he also had a major influence on planetary science and exploration at JPL. Recognition of this remarkable scientist and leader by the naming of Mount Sharp is highly fitting, and I hope it will serve to perpetuate his legacy."

The Mars Science Laboratory spacecraft was launched Nov. 26, 2011, bound for landing beside Mount Sharp inside Gale Crater on the evening of Aug. 5, PST (early Aug. 6, EST and Universal Time). The mission will use Curiosity to investigate whether the area has ever offered environmental conditions favorable for fostering microbial life, including chemical ingredients for life and energy for life.

In this photograph from the early 1980s, Sharp pauses during a day of field work on Mauna Loa volcano in Hawaii. Image credit: NASA / JPL-Caltech / Michael Malin.

Mount Sharp rises about 3 miles (5 kilometers) above the landing target on the crater floor, higher than Mount Rainier above Seattle, though broader and closer. It is not simply a rebound peak from the asteroid impact that excavated Gale Crater. A rebound peak may be at its core, but the mountain displays hundreds of flat-lying geological layers that may be read as chapters in a more complex history billions of years old.

Twice as tall as the sequence of colorful bands exposed in Arizona's Grand Canyon, the stack of layers in Mount Sharp results from changing environments in which layers are deposited, younger on top of older, eon after eon, and then partially eroded away.

Several craters on Mars contain mounds or mesas that may have formed in ways similar to Mount Sharp, and many other ancient craters remain filled or buried by rock layers. Some examples, including Gale, hold a mound higher than the surrounding crater rim, indicating that the mounds are remnant masses inside once completely filled craters. This presents a puzzle about how environmental conditions on Mars evolved.

Mars Science Laboratory (MSL). Credit: NASA / JPL

"This family of craters that were filled or buried and then exhumed or partially exhumed raises the question of what changed," said Ken Edgett of Malin Space Sciences, principal investigator for one of Curiosity's instruments. "For a long time, sedimentary materials enter the crater and stay. Then, after they harden into rock, somehow the rock gets eroded away and transported out of the crater."

Some lower layers of Mount Sharp might tell of a lake within Gale Crater long ago, or wind-delivered sediments subsequently soaked by groundwater. Orbiters have mapped water-telltale minerals in those layers. Liquid water is a starting point in describing conditions favorable for life, but just the beginning of what Curiosity can investigate. Higher layers may be deposits of wind-blown dust after a great drying-out on Mars.

"Mount Sharp is the only place we can currently access on Mars where we can investigate this transition in one stratigraphic sequence," said Caltech's John Grotzinger, chief scientist for the Mars Science Laboratory. "The hope of this mission is to find evidence of a habitable environment; the promise is to get the story of an important environmental breakpoint in the deep history of the planet. This transition likely occurred billions of years ago -- maybe even predating the oldest well-preserved rocks on Earth."

Possible explanations for how erosion shaped the mountain after layers were deposited include swirling winds carving away the edges, and perhaps later wet episodes leaving channels down the sides and fresher sediments on the crater floor. Clues about those episodes present Curiosity with other potentially habitable environments to investigate.

The Mars Science Laboratory is managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., a division of Caltech. For more information, visit: http://www.nasa.gov/msl .

Images (mentioned), Text, Credit: NASA / JPL / D.C. Agle.

Best regards, Orbiter.ch

Many Billions of Rocky Planets in the Habitable Zones around Red Dwarfs in the Milky Way

ESO - European Southern Observatory logo.

28 March 2012

 Artist’s impression of sunset on the super-Earth world Gliese 667 Cc

A new result from ESO’s HARPS planet finder shows that rocky planets not much bigger than Earth are very common in the habitable zones around faint red stars. The international team estimates that there are tens of billions of such planets in the Milky Way galaxy alone, and probably about one hundred in the Sun’s immediate neighbourhood. This is the first direct measurement of the frequency of super-Earths around red dwarfs, which account for 80% of the stars in the Milky Way.

This first direct estimate of the number of light planets around red dwarf stars has just been announced by an international team using observations with the HARPS spectrograph on the 3.6-metre telescope at ESO’s La Silla Observatory in Chile [1]. A recent announcement (http://www.eso.org/public/news/eso1204/), showing that planets are ubiquitous in our galaxy used a different method that was not sensitive to this important class of exoplanets.

The HARPS team has been searching for exoplanets orbiting the most common kind of star in the Milky Way — red dwarf stars (also known as M dwarfs [2]). These stars are faint and cool compared to the Sun, but very common and long-lived, and therefore account for 80% of all the stars in the Milky Way.

“Our new observations with HARPS mean that about 40% of all red dwarf stars have a super-Earth orbiting in the habitable zone where liquid water can exist on the surface of the planet,” says Xavier Bonfils (IPAG, Observatoire des Sciences de l'Univers de Grenoble, France), the leader of the team. “Because red dwarfs are so common — there are about 160 billion of them in the Milky Way — this leads us to the astonishing result that there are tens of billions of these planets in our galaxy alone.”

The HARPS team surveyed a carefully chosen sample of 102 red dwarf stars in the southern skies over a six-year period. A total of nine super-Earths (planets with masses between one and ten times that of Earth) were found, including two inside the habitable zones of Gliese 581 (http://www.eso.org/public/news/eso0915/) and Gliese 667 C respectively. The astronomers could estimate how heavy the planets were and how far from their stars they orbited.

By combining all the data, including observations of stars that did not have planets, and looking at the fraction of existing planets that could be discovered, the team has been able to work out how common different sorts of planets are around red dwarfs. They find that the frequency of occurrence of super-Earths [3] in the habitable zone is 41% with a range from 28% to 95%.

On the other hand, more massive planets, similar to Jupiter and Saturn in our Solar System, are found to be rare around red dwarfs. Less than 12% of red dwarfs are expected to have giant planets (with masses between 100 and 1000 times that of the Earth).

As there are many red dwarf stars close to the Sun the new estimate means that there are probably about one hundred super-Earth planets in the habitable zones around stars in the neighbourhood of the Sun at distances less than about 30 light-years [4].

"The habitable zone around a red dwarf, where the temperature is suitable for liquid water to exist on the surface, is much closer to the star than the Earth is to the Sun," says Stéphane Udry (Geneva Observatory and member of the team). "But red dwarfs are known to be subject to stellar eruptions or flares, which may bathe the planet in X-rays or ultraviolet radiation, and which may make life there less likely."

One of the planets discovered in the HARPS survey of red dwarfs is Gliese 667 Cc [5]. This is the second planet in this triple star system (see eso0939 for the first) and seems to be situated close to the centre of the habitable zone. Although this planet is more than four times heavier than the Earth it is the closest twin to Earth found so far and almost certainly has the right conditions for the existence of liquid water on its surface. This is the second super-Earth planet inside the habitable zone of a red dwarf discovered during this HARPS survey, after Gliese 581d was announced in 2007 and confirmed in 2009.

“Now that we know that there are many super-Earths around nearby red dwarfs we need to identify more of them using both HARPS and future instruments. Some of these planets are expected to pass in front of their parent star as they orbit — this will open up the exciting possibility of studying the planet’s atmosphere and searching for signs of life,” concludes Xavier Delfosse, another member of the team (http://www.eso.org/public/news/eso1210/).

Notes:

[1] HARPS measures the radial velocity of a star with extraordinary precision. A planet in orbit around a star causes the star to regularly move towards and away from a distant observer on Earth. Due to the Doppler effect, this radial velocity change induces a shift of the star’s spectrum towards longer wavelengths as it moves away (called a redshift) and a blueshift (towards shorter wavelengths) as it approaches. This tiny shift of the star’s spectrum can be measured with a high-precision spectrograph such as HARPS and used to infer the presence of a planet.

[2] These stars are called M dwarfs because they have the spectral class M. This is the coolest of the seven classes in the simplest scheme for classifying stars accordingly to decreasing temperature and the appearance of their spectra.

[3] Planets with a mass between one and ten times that of the Earth are called super-Earths. There are no such planets in our Solar System, but they appear to be very common around other stars. Discoveries of such planets in the habitable zones around their stars are very exciting because — if the planet were rocky and had water, like Earth — they could potentially be an abode of life.

[4] The astronomers used ten parsecs as their definition of “close”. This corresponds to about 32.6 light-years.

[5] The name means that the planet is the second discovered (c) orbiting the third component (C) of the triple star system called Gliese 667. The bright stellar companions Gliese 667 A and B would be prominent in the skies of Gliese 667 Cc. The discovery of Gliese  667 Cc was independently announced by Guillem Anglada-Escude and colleagues in February 2012, roughly two months after the electronic preprint of the Bonfils et al. paper went online. This confirmation of the planets Gliese 667 Cb and Cc by Anglada-Escude and collaborators was largely based on HARPS observations and data processing of the European team that were made publicly available through the ESO archive.

More information:

This research was presented in a paper “The HARPS search for southern extra-solar planets XXXI. The M-dwarf sample”, by Bonfils et al. to appear in the journal Astronomy & Astrophysics.

The team is composed of X. Bonfils (UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble, France [IPAG]; Geneva Observatory, Switzerland), X. Delfosse (IPAG), S. Udry (Geneva Observatory), T. Forveille (IPAG), M. Mayor (Geneva Observatory), C. Perrier (IPAG), F. Bouchy (Institut d’Astrophysique de Paris, CNRS, France; Observatoire de Haute-Provence, France), M. Gillon (Université de Liège, Belgium; Geneva Observatory), C. Lovis (Geneva Observatory), F. Pepe (Geneva Observatory), D. Queloz (Geneva Observatory), N. C. Santos (Centro de Astrofísica da Universidade do Porto, Portugal), D. Ségransan (Geneva Observatory), J.-L. Bertaux (Service d’Aéronomie du CNRS, Verrières-le-Buisson, France), and Vasco Neves (Centro de Astrofísica da Universidade do Porto, Portugal and UJF-Grenoble 1 / CNRS-INSU, Institut de Planétologie et d’Astrophysique de Grenoble, France [IPAG]).

The year 2012 marks the 50th anniversary of the founding of the European Southern Observatory (ESO). ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive astronomical observatory. It is supported by 15 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 40-metre-class European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

    Research papers: Bonfils et al. and Delfosse et al.: http://www.eso.org/public/archives/releases/sciencepapers/eso1214/eso1214a.pdf

http://www.eso.org/public/archives/releases/sciencepapers/eso1214/eso1214b.pdf

    Photos of the ESO 3.6-metre Telescope at La Silla: http://www.eso.org/public/images/archive/search/?adv=&subject_name=3.6

Image, Text, Credits: ESO / L. Calçada / Richard Hook / Université Joseph Fourier - Grenoble 1/Institut de Planétologie et d’Astrophysique de Grenoble / Xavier Bonfils.

Cheers, Orbiter.ch

Mars-Bound NASA Craft Adjusts Path, Tests Instruments

NASA - Mars Science Laboratory (MSL) patch.

March 27, 2012

Mars Science Laboratory Mission Status Report

NASA's Mars Science Laboratory spacecraft, halfway to Mars, adjusted its flight path today for delivery of the one-ton rover Curiosity to the surface of Mars in August.

Tests completed aboard Curiosity last week confirmed the health of science instruments the mission will use to learn whether an area holding an extensive record of Martian environmental history has ever offered conditions favorable for microbial life.

In the second of six planned trajectory correction maneuvers during the cruise to Mars, the spacecraft ignited thrusters for nearly nine minutes today. Spacecraft data and Doppler-effect changes in radio signal from the craft, monitored in the mission control room at NASA's Jet Propulsion Laboratory, Pasadena, Calif., indicate the maneuver succeeded.

"It is satisfying to get the second maneuver under our belts and know we are headed in the right direction," said JPL's Erisa Hines, systems lead for the maneuver. "The cruise system continues to perform very well."

"We are now on a trajectory that will put us much closer to the point we want to hit on Aug. 5," added Tomas Martin-Mur, navigation team chief for the mission.

This is an artist's concept of NASA's Mars Science Laboratory spacecraft during its cruise phase between launch and final approach to Mars. Image Credit: NASA / JPL-Caltech.

The halfway point of the trip from Earth to Mars will be April 1, in terms of duration. The mission launched Nov. 26, 2011. It will land the evening of Aug. 5, 2012, PDT (early Aug. 6, EDT and Universal Time).

One of Curiosity's 10 science instruments, the Radiation Assessment Detector (RAD) has been collecting data for three months, monitoring the natural radiation environment in interplanetary space. This information, particularly effects RAD has measured from recent solar flares, is crucial for design of human missions to Mars.

In the past two weeks, the rover team has checked the status of the other nine of Curiosity's science instruments, powering them on for the first time since before launch. All the instruments passed these checkouts.

"The types of testing varied by instrument, and the series as whole takes us past the important milestone of confirming that all the instruments survived launch," said Betina Pavri of NASA's Jet Propulsion Laboratory, Pasadena, Calif., science payload test engineer for the mission. "These checkouts provide a valuable calibration and characterization opportunity for the instruments, including camera dark images and a measurement of zero pressure in the vacuum of space for the rover weather station's pressure sensor."

Curiosity's landing site is near the base of a mountain inside Gale Crater, near the Martian equator. Researchers plan to use Curiosity to study layers in the mountain that hold evidence about wet environments of early Mars.

An artist's concept of the Mars Science Laboratory. Credit: NASA / JPL-Caltech.

First, the spacecraft must get there. Today's maneuver nudged the spacecraft one-seventh as much as the flight's first course adjustment, on Jan. 11. After the first maneuver, the trajectory would have put Curiosity about 3,000 miles (5,000 kilometers) and 20 minutes away from entering Mars' atmosphere at the right place and time. Like that maneuver, today's combined two ways of using thruster engines while the whole spacecraft spins at two rotations per minute.

The spacecraft's cruise stage carries eight thrusters grouped into two sets of four. The maneuver began with about three minutes of firing one thruster in each set to change velocity along the direction of the axis of rotation. Then, to push the spacecraft in a direction perpendicular to the axis, each set of thrusters was used for five-second pulses when the spacecraft's rotation put that set at the correct orientation. The maneuver used more than 60 of these pulses spaced about 10 seconds apart.

"The purpose is to put us on a trajectory to the point in the Mars atmosphere where we need to be for a safe and accurate landing," said Mau Wong, maneuver analyst at JPL.

The descent from the top of Mars' atmosphere to the surface will employ bold techniques enabling use of a smaller target area and larger landed payload than were possible for any previous Mars mission. These innovations, if successful, will place a well-equipped mobile laboratory into a locale especially well suited for its mission of learning. The same innovations advance NASA toward capabilities needed for human missions to Mars.

As of March 29, the spacecraft will have traveled about 196 million miles (316 million kilometers) of its 352-million-mile (567-million-kilometer) flight to Mars.

JPL, a division of the California Institute of Technology in Pasadena, manages the mission for the NASA Science Mission Directorate, Washington. More information about Curiosity is online at 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), Text, Credit: NASA / JPL / Guy Webster.

Greetings, Orbiter.ch

NASA Measures Impact of Huge Solar Flare on Earth's Atmosphere

NASA - TIMED Mission patch.

March 27, 2012

A key NASA instrument that can directly measure the impact of solar events on the Earth's upper atmosphere has weighed in on the huge flare that impacted Earth last week.

The flare was considered one of the largest solar events in years even though its impact on the power grid and communications was minimal due to the angle it hit Earth.

NASA Science - The Surprising Power of a Solar Storm

Its direct interaction with the upper atmosphere was measured by NASA's SABER (Sounding of the Atmosphere using Broadband Emission Radiometry) instrument orbiting on the TIMED (Thermosphere, Ionosphere, Mesosphere, Energetics and Dynamics) satellite.

The upper atmosphere heated up, and huge spikes occurred in infrared emission from nitric oxide and carbon dioxide, said Marty Mlynczak, SABER's associate-principal investigator at NASA's Langley Research Center in Hampton, Va.

Sol 'waking up'

"It's been seven years since we've had a storm like that," he said. "This is the first major storm event since the deep solar minimum of 2008-2009. We are finally seeing the Sun 'wake up' as it proceeds to the next solar maximum."

A surge of infrared radiation from nitric oxide molecules on March 8-10, 2012, signals the biggest upper-atmospheric heating event in seven years. Credit: NASA / SABER, TIMED.

A solar maximum is a period of increased activity on the Sun, and minimum-to-maximum-to-minimum cycles generally last 11 years each. Solar activity began to pick up in 2010, is steadily increasing and should peak in late 2014.

As the Sun becomes more active, Mlynczak said, it emits more ultraviolet radiation and produces more solar flares - coronal mass ejections (CMEs) - which are absorbed in the atmosphere. "More heating results, and the atmosphere gets warmer, and the infrared emission increases," he said.

"We don't know yet how these affect weather or climate -- likely there is not any direct effect," he said, "but there may be, over time, influences on ozone that affect climate."

"These results are very timely," said James Russell, SABER's principal investigator at Hampton University in Hampton, Va. "SABER is cataloging the atmospheric response to solar forcing and is providing a solid baseline for examining long-term changes in the climatology of the upper atmosphere."

"The data set is a vital resource for study of atmospheric trends, for validating atmospheric models of the region, and for evaluating our understanding of solar/atmosphere coupling, he said.

Unique Record

SABER is one of four instruments on the TIMED spacecraft launched in December 2001. TIMED studies the Earth's mesosphere and lower thermosphere, the least explored and least understood region of our atmosphere.

"SABER has a unique, continuous record of over 3,700 days observation of the climate and energy balance of the Earth's upper and outer atmosphere," Mlynczak said.

"From this, we are learning with each event how sensitive this region of the Earth's atmosphere is to short- and long-term variability of the Sun," he said. "We have documented the decline of the prior solar cycle, the deep minimum and the 'ground state' of the atmosphere during that time, and are now seeing the uptick."

Artist's concept of the TIMED spacecraft. Credit: NASA / JHU / APL

TIMED was designed to operate for two years but has operated flawlessly for more than 10 years. Another NASA review is planned in 2013 to determine if SABER will continue operating for at least three more years.

"This is well before the predicted solar maximum," Mlynczak said. There are no other measurements like it, and the entire SABER science team is working hard to make the scientific case to keep the mission operating."

Partners in the SABER mission include Hampton University in Hampton, Va.; Science Systems and Applications, Inc.; GATS Inc.; NASA's Goddard Spaceflight Center in Greenbelt, Md.; and Johns Hopkins University Applied Physics Laboratory in Laurel, Md. Utah State University Space Dynamics Laboratory built SABER.

Related links:

Hampton University SABER: http://saberoutreach.hamptonu.edu/

SABER Facts: http://www.nasa.gov/centers/langley/news/factsheets/SABER.html

TIMED Mission: http://www.timed.jhuapl.edu/WWW/index.php

TIMED Position: http://www.timed.jhuapl.edu/WWW/main/where.php

Images (mentioned), Video, Text, Credit: NASA Langley Research Center /  Michael Finneran.

Greetings, Orbiter.ch

Cassini to Make Closest Pass Yet over Enceladus South Pole

NASA / ESA - Cassini Mission to Saturn patch.

03.26.12

NASA's Cassini spacecraft is preparing to make its lowest pass yet over the south polar region of Saturn's moon Enceladus, where icy particles and water vapor spray out in glittering jets. The closest approach, at an altitude of about 46 miles (74 kilometers), will occur around 11:30 a.m. PDT (2:30 p.m. EDT) on March 27.

Artist's concept of the Mar. 27, 2012, flyby of Saturn's moon Enceladus by NASA's Cassini spacecraft. Image credit: NASA / JPL-Caltech.

This flyby is primarily designed for Cassini's ion and neutral mass spectrometer, which will attempt to "taste" particles from the jets. Scientists using this spectrometer will utilize the data to learn more about the composition, density and variability of the plume. The Cassini plasma spectrometer, which team members worked to return to service so it could gather high-priority measurements during this flyby, will also be analyzing Saturn's magnetic and plasma environment near Enceladus and sampling the plume material near closest approach.

In addition, the composite infrared spectrometer will also be looking for hot spots on Enceladus, and the imaging cameras will be snapping pictures.

At least four distinct plumes of water ice spew out from the south polar region of Saturn's moon Enceladus in this dramatically illuminated image. Image credit: NASA / JPL / Space Science Institute.

A flyby in October 2015 will bring Cassini about 16 miles (25 kilometers) closer to the Enceladus surface near the south pole. Cassini's closest approach to any part of Enceladus occurred on Oct. 9, 2008, when it flew within about 16 miles (25 kilometers) of the surface at the equator.

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

For more information about the Cassini-Huygens mission visit: http://www.nasa.gov/cassini and http://saturn.jpl.nasa.gov & http://www.esa.int/esaMI/Cassini-Huygens/

Images (mentioned), Text, Credit: NASA / JPL / Jia-Rui C. Cook.

Best regards, Orbiter.ch

Artemis: the ATV whisperer

Aerospace Engineering.

26 March 2012

ESA’s Artemis communications satellite is in action again to ensure the safe arrival of Europe’s third Automated Transfer Vehicle at the International Space Station with vital supplies.

Containing fresh supplies of fuel, water, oxygen, air, food, clothing, experiments and spare parts, ATV Edoardo Amaldi is a true lifeline to the astronauts on the Space Station. A prompt arrival is critical for the orbital outpost.

Artemis is dedicated to ATV-3 throughout the vessel’s free-flying phase up to the docking with the Station Wednesday night. NASA’s own satellites provide backup to Artemis during the attached phase, while Artemis will act as backup during the other phases and in emergency situations.

Artemis satellite artist's view

Artemis is handling communications between Edoardo Amaldi and the ATV Control Centre in Toulouse, France.

Hovering some 36 000 km above the equator at 21.4ºE – directly over the Democratic Republic of the Congo – Artemis is routing telemetry and commands to and from the control centre whenever the satellite has the Station or ATV in its view.

As ATV-3 circles the globe, Artemis has close to 40 minutes of continuous contact at a time.

ATV description

The first two ATV missions were also supported by Artemis. Working in parallel with NASA, Artemis was used as the main relay while the ATVs were attached to the Station and provided back up for commands and telemetry during rendezvous, docking, undocking and reentry. 

ESA’s first data-relay satellite has been orbiting Earth for more than 10 years and pioneered many of the advances used in satcoms today.

 Antenna at ESA's Redu station

Artemis created the first laser data link between satellites in different orbits; it was the first telecommunications satellite to be extensively reprogrammed in orbit; it was the first to power its way to geostationary orbit, 36 000 km up, with ion thrusters after surviving the longest-ever drift to its destination.

Artemis is the precursor to Europe’s new European Data Relay System, now being built in a public–private partnership between ESA and Astrium Services.

For more information see the links below.

Related links:

ARTES 7 EDRS: http://telecom.esa.int/telecom/www/area/index.cfm?fareaid=59

ATV-3 launch highlight (replay): http://multimedia.esa.int/Videos/2012/03/ATV-3-Launch-highlights

Images, Text, Credits: ESA / J.Huart / D. Galardini.

Greetings, Orbiter.ch

Filigree and Shadow

NASA - Galaxy Evolution Explorer (GALEX) patch.

March 26, 2012

Wispy tendrils of hot dust and gas glow brightly in this ultraviolet image of the Cygnus Loop Nebula, taken by NASA’s Galaxy Evolution Explorer. The nebula lies about 1,500 light-years away, and is a supernova remnant, left over from a massive stellar explosion that occurred 5,000-8,000 years ago. The Cygnus Loop extends more than three times the size of the full moon in the night sky, and is tucked next to one of the 'swan’s wings' in the constellation of Cygnus.

GALEX spacecraft

The filaments of gas and dust visible here in ultraviolet light were heated by the shockwave from the supernova, which is still spreading outward from the original explosion. The original supernova would have been bright enough to be seen clearly from Earth with the naked eye.

For more information about GALEX Mission, visit: http://www.nasa.gov/mission_pages/galex/index.html

Images, Text, Credit: NASA / JPL-Caltech.

Cheers, Orbiter.ch