samedi 15 mars 2014

Successful launch for Proton-M with Express-AT1 and Express-AT2 aboard












ROSCOSMOS logo.

March 15, 2014

Proton-M whit Express-AT1 & Express-AT2 at the launch-pad, ready for launch

A Russian Proton-M rocket successfully launched from Baikonur this evening, March 15th 2014 at 23:08 GMT.

video
Russian Proton-M Rocket Launches Express AT1 & AT2 satellites


The rocket carried two communications satellites into orbit. Built for the Russian Satellite Communications Company Express AT1 and Express AT2 were placed into orbit.

Express AT1 communication satellite
 
Express-AT2 communication satellite

AT1 will be positioned at 56 degrees East with 32 Ku-Band transponders to cover Russia. AT2 will be positioned at 140 degrees East and will serve the Western portion of Russia. Express-AT2, with 3 kilowatts of power for 16 Ku-band transponders.

Ku-band coverage by AT1 Wide
 
 Ku-band coverage by AT1 East

Ku-band coverage by AT2

The Express-AT 2 is a Direct-To-Home broadcasting satellite for russian domestic communication services. While the spacecraft itself is built by russian RSCC (Kosmicheskiya Svyaz), the communication payload is built by Thales Alenia Space.

Related link:

Russian Satellite Communications Company (RSCC): http://eng.rscc.ru/

Images, Video, Text, Credits: ROSCOSMOS / ROSCOSMOS TV / TsENKI TV / RSCC / Orbiter.ch Aerospace.

Cheers, Orbiter.ch

World Wide Web born at CERN 25 years ago












CERN - European Organization for Nuclear Research logo.

March 15, 2014


The image above by Tim Berners-Lee's proposal for the World Wide Web in March 1989 (Image: CERN).

In March 1989 Tim Berners-Lee, a scientist working at CERN, submitted a proposal to develop a radical new way of linking and sharing information over the internet. The document was entitled Information Management: A Proposal. And so the web was born.

The first website at CERN – and in the world – was dedicated to the World Wide Web project itself. Last April CERN initiated a project to restore the first website, and to bring back the spirit of that time through its technical innovation and the founding principles of openness and freedom.

In 1993 CERN put the World Wide Web software in the public domain. CERN made the next release available with an open licence, as a more sure way to maximise its dissemination. Through these actions, making the software required to run a web server freely available, along with a basic browser and a library of code, the web was allowed to flourish.

World Wide Web

"Beyond CERN's role in helping us understand the universe, it was a great place to work in 1989," said Tim Berners-Lee. "CERN was an early adopter of Internet protocols, and their support for a Royalty-Free Web has been a key to its widespread adoption today."

Now Tim Berners-Lee, the World Wide Web Consortium (W3C) and the World Wide Web Foundation are launching a series of initiatives to mark the 25th anniversary of the original proposal.

In addition, Berners-Lee and the Web Foundation are launching "The web we want" campaign to promote a global dialogue and change in public policy to ensure that the web remains an open, free, accessible medium – so that everyone on the planet can participate in the free flow of knowledge, ideas and creativity online.

Opinion pieces on this topic:

"Minimising the muddle" – Peggie Rimmer, early web contributor: http://home.web.cern.ch/cern-people/opinion/2014/03/minimising-muddle

"Good old Bitnet, and the rise of the World Wide Web" – Richard Jacobsson, senior physicist on the LHCb experiment: http://home.web.cern.ch/cern-people/opinion/2014/03/good-old-bitnet-and-rise-world-wide-web

"On the open internet and the free web" – David Foster, deputy head of CERN's IT department: http://home.web.cern.ch/cern-people/opinion/2014/03/open-internet-and-free-web

"Not at all vague and much more than exciting" – Maria Dimou, CERN computer scientist and early web contributor: http://home.web.cern.ch/cern-people/opinion/2014/03/not-all-vague-and-much-more-exciting

Note:

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

Related links:

The first website at CERN: http://info.cern.ch/hypertext/WWW/TheProject.html

World Wide Web Consortium (W3C): http://www.w3.org/

World Wide Web Foundation: http://www.webfoundation.org/

Images, Text, Credits: CERN / Cian O'Luanaigh.

Best regards, Orbiter.ch

vendredi 14 mars 2014

The correction of the ISS orbit












ISS - International Space Station patch.

03/14/2014

March 13, 2014 the correction of the orbit of the International Space Station.

According to calculations by the ballistic and navigation support Mission Control Center FSUE TsNIIMash engines cargo spacecraft Progress M-21M were included in the 07 8:00 Moscow time and worked 462 seconds. As a result, ISS has received incremental velocity of 1.1 m/s. The average height of its orbit increased by 2 km and reached 414.1 km.

ISS reboost by Progress-M

According to the service ballistic and navigation support MCC after the ISS orbit maneuver parameters were as follows:

- Minimum height -413.6 km,
- Maximum height of -429.3 km,
- Period - 92.7934 min
- Inclination -51,669 °.

ROSCOSMOS Press Release: http://www.federalspace.ru/20333/

Image, Text, Credits: Roscosmos press service / NASA / Translation: Orbiter.ch Aerospace.

Greetings, Orbiter.ch

Your 15 Minutes of 'Frame' - from NASA's Cassini












NASA / ESA - Cassini Mission to Saturn patch.

March 14, 2014

video
Cassini: Coming Attractions at Saturn

Video above: What incredible things will the Cassini spacecraft at Saturn see and do over the next few years?

Arguably the most photogenic planet in the solar system, Saturn is the sixth planet from the sun and the second largest planet after Jupiter. With its luminous striped surface and stunning ring system, the planet is a wonder to view, especially from orbit, as NASA's Cassini spacecraft has demonstrated since arriving at the Saturn system in 2004.

Over the years, the Cassini mission website has been sharing raw, unprocessed versions of images sent to Earth by the spacecraft. On June 30 (July 1 EDT), Cassini will celebrate 10 years exploring Saturn, its rings and moons. To help mark 10 years in orbit, NASA's Jet Propulsion Laboratory in Pasadena, Calif., has created a special gallery on the Saturn website where members of the public can experience "15 minutes of frame" by submitting their own amateur images made up from image data brought back by Cassini.

With more than a half-dozen images and GIFs already live on the page, users are invited to visit Cassini's raw image database, dig through the treasure trove and create their own digital masterpiece and suggested caption. The submission process is as simple as filling out a form and uploading the image. Guidelines and further information can be found on the Cassini website.


Image above: To help mark its 10th anniversary of exploring Saturn, its moons and rings, NASA's Cassini mission invites the public to transform images from the spacecraft for posting on an amateur image page. Image Credit: NASA/JPL-Caltech.

Now that Cassini has completed its first decade of observations, mission planners are looking forward to the next phase, when the spacecrafts's instruments will return additional data and images. The mission will probe the densest part of the geysers spewing from Enceladus, and dive between Saturn and its innermost ring.

As part of the 10-year anniversary celebration, the Cassini team is releasing a video preview of the next four years of the mission: http://youtu.be/fAQM9rfZq7w
     
The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. 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, Colo.

For more information about Cassini amateur images, visit: http://saturn.jpl.nasa.gov/photos/amateurimages/

For more information about Cassini, visit: http://saturn.jpl.nasa.gov/ and http://www.nasa.gov/cassini

Image, Video, Text, Credits: NASA / JPL / Jane Platt.

Greetings, Orbiter.ch

Europe exposed












ESA - Proba-V Mission logo.

March 14, 2014


A nearly cloud-free view of Europe, part of a global mosaic of Proba-V images acquired on 9 March.

Our green continent is depicted at a resolution of 333 m, with snow capping the peaks of the Pyrenees and Alps bordering Italy.

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.

The camera’s continent-spanning 2250 km 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.

Artist's view of  Proba-V satellite

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

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

Images, Text, Credits: ESA / VITO.

Cheers, Orbiter.ch

jeudi 13 mars 2014

Mid-Level Solar Flare Seen by NASA's SDO












NASA - Solar Dynamics Observatory patch.

March 13, 2014


Image above: NASA's Solar Dynamics Observatory captures images of the sun in many wavelengths of light at the same time, each of which is typically colorized in a different color. Each wavelength shows different aspects of the same event, as seen in these three images of a solar flare on March 12, 2014. Image Credit: NASA/SDO/Goddard Space Flight Center.

The sun emitted a mid-level solar flare, peaking at 6:34 p.m. EDT on March 12, 2014, and NASA's Solar Dynamics Observatory, or SDO, captured an image of it. Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.

To see how this event may impact Earth, please visit NOAA's Space Weather Prediction Center at http://spaceweather.gov, the U.S. government's official source for space weather forecasts, alerts, watches and warnings.


Image above: A solar flare erupts on the far right side of the sun, in this image captured by NASA's Solar Dynamics Observatory. The flare peaked at 6:34 p.m. EDT on March 12, 2014. Image Credit: NASA/SDO/Goddard Space Flight Center.

This flare is classified as an M9.3 flare, just slightly weaker than the most intense flares, which are labeled X-class. The letters denote broad categories of strength, while the numbers provide more information. An M2 is twice as intense as an M1, an M3 is three times as intense, etc.

This M9.3 flare was emitted by an active region — a magnetically strong and complex region on the sun's surface — labeled AR 11996. 

Updates will be provided as they are available on the flare and whether there was an associated coronal mass ejection, or CME, another solar phenomenon that can send solar particles into space and affect electronic systems in satellites and on Earth.

Related Links:

Frequently Asked Questions Regarding Space Weather: http://www.nasa.gov/mission_pages/sunearth/spaceweather/index.html

View Other Past Solar Activity: http://www.nasa.gov/mission_pages/sunearth/multimedia/Solar-Events.html

Images (mentioned),  Text, Credits: NASA's Goddard Space Flight Center / Karen C. Fox.

Best regards, Orbiter.ch

Reducing debris threat from satellite batteries

ESA - Clean Space logo.

13 March 2014

Across a satellite’s working life, batteries keep the craft’s heart beating whenever it leaves sunlight. But after its mission ends, those same batteries may threaten catastrophe.

Space debris mitigation rules require the complete deactivation of electrical power sources aboard a satellite on retirement, in order to guard against explosive accidents that might produce fresh debris dangerous to other satellites.

Exploding satellite

Now a new study by ESA’s Clean Space initiative – tasked with reducing the space industry’s environmental impacts on both Earth and space – aims to evaluate battery behaviour after a satellite shuts down, assessing the risk of breakup and ensuring full ‘passivation’.

Batteries are among a satellite’s bulkier items of equipment. Typically, they feed their host with power during launch. Once in orbit, it switches to power from its solar arrays, but the battery is an important backup to store power for eclipses and emergencies.

Proba lithium-ion battery

To reach the high reliability and performance a satellite demands, extending across many months or years, batteries are carefully designed and extensively tested in advance of launch.

By contrast, their behaviour after their parent mission has been shut down remains a relative blind spot.

As a satellite drifts freely, could batteries endure the harsh environment of orbit – including wild temperature swings, degradation of thermal control and components as well as radiation exposure – without leakage or bursting?

Some past satellite breakups have been triggered by battery malfunctions, although mostly before the 1990s and involving older non-lithium designs.

This multidisciplinary study aims to ensure a fully inert power system at the end of a mission, perhaps through physical disconnection, while also preventing accidental premature passivation.

Bidders are welcome on this contract. For more information check the invitation package, accessible via ESA’s tendering system: http://www.esa.int/About_Us/Industry/Industry_how_to_do_business/ESA_s_Invitation_to_Tender_System_EMITS

Related links:

EMITS: http://emits.esa.int/emits/owa/emits.main

Batteries at the heart of ESA space missions: http://www.esa.int/Our_Activities/Technology/Batteries_at_the_heart_of_ESA_space_missions

Keeping the power on in space: http://www.esa.int/Our_Activities/Space_Engineering/Keeping_the_power_on_in_space

About Clean Space: http://www.esa.int/Our_Activities/Space_Engineering/Clean_Space/What_is_Clean_Space

Images, Text, Credit: ESA.

Greetings, Orbiter.ch

mercredi 12 mars 2014

VLT Spots Largest Yellow Hypergiant Star












ESO - European Southern Observatory logo.

12 March 2014

Mix of new and old observations reveals exotic binary system

The field around yellow hypergiant star HR 5171

ESO’s Very Large Telescope Interferometer has revealed the largest yellow star — and one of the ten largest stars found so far. This hypergiant has been found to measure more than 1300 times the diameter of the Sun, and to be part of a double star system, with the second component so close that it is in contact with the main star. Observations spanning over sixty years, some from amateur observers, also indicate that this rare and remarkable object is changing very rapidly and has been caught during a very brief phase of its life.

Using ESO’s Very Large Telescope Interferometer (VLTI), Olivier Chesneau (Observatoire de la Côte d’Azur, Nice, France) and an international team of collaborators have found that the yellow hypergiant star HR 5171 A [1] is absolutely huge — 1300 times the diameter of the Sun and much bigger than was expected [2]. This makes it the largest yellow star known. It is also in the top ten of the largest stars known — 50% larger than the famous red supergiant Betelgeuse — and about one million times brighter than the Sun.

Artist’s impression of the yellow hypergiant star HR 5171

“The new observations also showed that this star has a very close binary partner, which was a real surprise,” says Chesneau. “The two stars are so close that they touch and the whole system resembles a gigantic peanut.”

The astronomers made use of a technique called interferometry to combine the light collected from multiple individual telescopes, effectively creating a giant telescope up to 140 metres in size. The new results prompted the team to thoroughly investigate older observations of the star spanning more than sixty years, to see how it had behaved in the past [3].

The yellow hypergiant star HR 5171 in the constellation of Centaurus

Yellow hypergiants are very rare, with only a dozen or so known in our galaxy — the best-known example being Rho Cassiopeiae. They are among the biggest and brightest stars known and are at a stage of their lives when they are unstable and changing rapidly. Due to this instability, yellow hypergiants also expel material outwards, forming a large, extended atmosphere around the star.

Despite its great distance of nearly 12 000 light-years from Earth, the object can just about be seen with the naked eye [4] by the keen-sighted. HR 5171 A has been found to be getting bigger over the last 40 years, cooling as it grows, and its evolution has now been caught in action. Only a few stars are caught in this very brief phase, where they undergo a dramatic change in temperature as they rapidly evolve.

video
Artist’s impression of the yellow hypergiant star HR 5171 

By analysing data on the star’s varying brightness, using observations from other observatories, the astronomers confirmed the object to be an eclipsing binary system where the smaller component passes in front and behind the larger one as it orbits. In this case HR 5171 A is orbited by its companion star every 1300 days. The smaller companion is only slightly hotter than HR 5171 A’s surface temperature of 5000 degrees Celsius.

Chesneau concludes “The companion we have found is very significant as it can have an influence on the fate of HR 5171 A, for example, stripping off its outer layers and modifying its evolution.”

video
Zooming in on the yellow hypergiant star HR 5171

This new discovery highlights the importance of studying these huge and short-lived yellow hypergiants, and could provide a means of understanding the evolutionary processes of massive stars in general.

Notes:

[1] The star is also known as V766 Cen, HD 119796 and HIP 67261.

[2] Comparable objects seem to all be red supergiants which reach 1000–1500 times the radius of the Sun and have initial masses not exceeding 20–25 Solar masses. The radius of a yellow supergiant was expected to be 400–700 times that of the Sun.

[3] Spectral data were obtained using the Anglo–Australian Telescope with the University College London Echelle Spectrograph (UCLES), at the South African Astronomical Observatory (SAAO), with PUCHEROS, from the Pontificia Universidad de Chile (PUC) and through coronagraphic observations with the Near-Infrared Coronagraphic Imager (NICI) on the Gemini South telescope. Archival photometric datasets examined include infrared photometry from the South African Astronomical Observatory spanning the time frame from 1975 to 2013 and other datasets from 1983 to 2002, including some amateur observations. The agreement of professional results with those from amateur astronomer Sebastian Otero (2000–2013) is considered by the authors to be “excellent”, and “illustrates the quality of these amateur observations”.

[4] The visual magnitude of HR 5171 A is seen to vary between 6.10 and 7.30. It and can be viewed in the constellation of Centaurus (The Centaur).

More information:

This research was presented in a paper “The yellow hypergiant HR 5171 A: Resolving a massive interacting binary in the common envelope phase”, by Chesneau et al., to appear in the journal Astronomy & Astrophysics.

The team is composed of O. Chesneau (Laboratoire Lagrange, Univ. Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d’Azur, Nice, France [Lagrange]), A. Meilland (Lagrange), E. Chapellier (Lagrange), F. Millour (Lagrange), A.M. Van Genderen (Leiden Observatory, Leiden, The Netherlands), Y. Nazé (Le Fonds de la Recherche Scientifique, Liège, Belgium), N. Smith (Steward Observatory, Tucson, USA), A. Spang (Lagrange), J.V. Smoker (ESO, Santiago, Chile), L. Dessart (Aix Marseille Université, CNRS, Laboratoire d’Astrophysique de Marseille, Marseille, France), S. Kanaan (Instituto de Física y Astronomía, Universidad de Valparaíso, Chile [IFA]), Ph. Bendjoya (Lagrange), M.W. Feast (South African Astronomical Observatory, South Africa [SAAO]), J.H. Groh (Geneva Observatory, Geneva, Switzerland), A. Lobel (Royal Observatory of Belgium, Brussels, Belgium), N. Nardetto (Lagrange), S. Otero (American Association of Variable Star Observers, Cambridge, MA, USA), R.D. Oudmaijer (School of Physics & Astronomy, University of Leeds, UK), A.G. Tekola (SAAO and Las Cumbres Observatory Global Telescope Network, Goleta, CA, USA), P.A. Whitelock (SAAO), C. Arcos (IFA), M. Curé (IFA) and L. Vanzi (Department of Electrical Engineering and Center of Astro Engineering, Pontificia Universidad Catolica de Chile, Santiago, Chile).

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. 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 the 39-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Links:

Research paper (ArXiV pre-print): http://arxiv.org/pdf/1401.2628v2.pdf

Photos of the VLTI: http://www.eso.org/public/images/?search=vlti

Photos of AMBER: http://www.eso.org/public/images/?search=AMBER

Images, Text, Credits: ESO/Digitized Sky Survey 2/IAU and Sky & Telescope / Videos: ESO/Nick Risinger (skysurvey.org)/Digitized Sky Survey 2. Music: movetwo.

Cheers, Orbiter.ch

mardi 11 mars 2014

Long-Term Warming Likely to Be Significant Despite Recent Slowdown










NASA logo.

March 11, 2014

A new NASA study shows Earth's climate likely will continue to warm during this century on track with previous estimates, despite the recent slowdown in the rate of global warming.

This research hinges on a new and more detailed calculation of the sensitivity of Earth's climate to the factors that cause it to change, such as greenhouse gas emissions. Drew Shindell, a climatologist at NASA's Goddard Institute for Space Studies in New York, found Earth is likely to experience roughly 20 percent more warming than estimates that were largely based on surface temperature observations during the past 150 years.

Shindell's paper on this research was published March 9 in the journal Nature Climate Change.


Image above: A new NASA study suggests that projections of Earth's future warming should be more in line with previous estimates that indicated a higher sensitivity to increasing greenhouse gas emissions. Image Credit: NASA SVS/NASA Center for Climate Simulation.

Global temperatures have increased at a rate of 0.22 Fahrenheit (0.12 Celsius) per decade since 1951. But since 1998, the rate of warming has been only 0.09 F (0.05 C) per decade -- even as atmospheric carbon dioxide continues to rise at a rate similar to previous decades. Carbon dioxide is the most significant greenhouse gas generated by humans.

Some recent research, aimed at fine-tuning long-term warming projections by taking this slowdown into account, suggested Earth may be less sensitive to greenhouse gas increases than previously thought. The Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC), which was issued in 2013 and was the consensus report on the state of climate change science, also reduced the lower range of Earth's potential for global warming.

To put a number to climate change, researchers calculate what is called Earth's "transient climate response." This calculation determines how much global temperatures will change as atmospheric carbon dioxide continues to increase – at about 1 percent per year -- until the total amount of atmospheric carbon dioxide has doubled. The estimates for transient climate response range from near 2.52 F (1.4 C) offered by recent research, to the IPCC's estimate of 1.8 F (1.0 C). Shindell's study estimates a transient climate response of 3.06 F (1.7 C), and determined it is unlikely values will be below 2.34 F (1.3 C).

Shindell's paper further focuses on improving our understanding of how airborne particles, called aerosols, drive climate change in the Northern Hemisphere. Aerosols are produced by both natural sources – such as volcanoes, wildfire and sea spray – and sources such as manufacturing activities, automobiles and energy production. Depending on their make-up, some aerosols cause warming, while others create a cooling effect. In order to understand the role played by carbon dioxide emissions in global warming, it is necessary to account for the effects of atmospheric aerosols.

While multiple studies have shown the Northern Hemisphere plays a stronger role than the Southern Hemisphere in transient climate change, this had not been included in calculations of the effect of atmospheric aerosols on climate sensitivity. Prior to Shindell's work, such calculations had assumed aerosol impacts were uniform around the globe.

This difference means previous studies have underestimated the cooling effect of aerosols. When corrected, the range of likely warming based on surface temperature observations is  in line with earlier estimates, despite the recent slowdown.

One reason for the disproportionate influence of the Northern Hemisphere, particularly as it pertains to the impact of aerosols, is that most man-made aerosols are released from the more industrialized regions north of the equator. Also, the vast majority of Earth's landmasses are in the Northern Hemisphere. This furthers the effect of the Northern Hemisphere because land, snow and ice adjust to atmospheric changes more quickly than the oceans of the world.

"Working on the IPCC, there was a lot of discussion of climate sensitivity since it's so important for our future," said Shindell, who was lead author of the IPCC Fifth Assessment Report's chapter on Anthropogenic and Natural Radiative Forcing. "The conclusion was that the lower end of the expected warming range was smaller than we thought before. That was a big discussion. Yet, I kept thinking, we know the Northern Hemisphere has a disproportionate effect, and some pollutants are unevenly distributed. But we don't take that into account. I wanted to quantify how much the location mattered."

Shindell's climate sensitivity calculation suggests countries around the world need to reduce greenhouse gas emissions at the higher end of proposed emissions reduction ranges to avoid the most damaging consequences of climate change. "I wish it weren't so," said Shindell, "but forewarned is forearmed."

For more information about the Goddard Institute for Space Studies, visit: http://www.giss.nasa.gov

Image (mentioned), Text, Credits: NASA / Steve Cole / Goddard Institute for Space Studies / Leslie McCarthy.

Greetings, Orbiter.ch

Venus glory












ESA - Venus Express Mission patch.

11 March 2014

Venus glory

A rainbow-like feature known as a ‘glory’ has been seen by ESA’s Venus Express orbiter in the atmosphere of our nearest neighbour – the first time one has been fully imaged on another planet.

Rainbows and glories occur when sunlight shines on cloud droplets – water particles in the case of Earth. While rainbows arch across wide swathes of the sky, glories are typically much smaller and comprise a series of coloured concentric rings centred on a bright core.

Glories are only seen when the observer is situated directly between the Sun and the cloud particles that are reflecting sunlight. On Earth, they are often seen from aeroplanes, surrounding the shadow of the aircraft on the clouds below, or around the shadow of climbers atop misty mountain peaks.

Venus glory details

A glory requires two characteristics: the cloud particles are spherical, and therefore most likely liquid droplets, and they are all of a similar size.

The atmosphere of Venus is thought to contain droplets rich in sulphuric acid. By imaging the clouds with the Sun directly behind the Venus Express spacecraft, scientists hoped to spot a glory in order to determine important characteristics of the cloud droplets.

They were successful. The glory in the images here was seen at the Venus cloud tops, 70 km above the planet’s surface, on 24 July 2011. It is 1200 km wide as seen from the spacecraft, 6000 km away.

Simulated views of glory on Venus and Earth

From these observations, the cloud particles are estimated to be 1.2 micrometres across, roughly a fiftieth of the width of a human hair.

The fact that the glory is 1200 km wide means that the particles at the cloud tops are uniform on this scale at least.

The variations of brightness of the rings of the observed glory is different than that expected from clouds of only sulphuric acid mixed with water, suggesting that other chemistry may be at play.

One idea is that the cause is the “UV-absorber”, an unknown atmospheric component responsible for mysterious dark markings seen in the cloud tops of Venus at ultraviolet wavelengths. More investigation is needed to draw a firm conclusion.

Further information:

“Glory on Venus Cloud Tops and the Unknown UV Absorber,” by W.J. Markiewicz et al, is accepted for publication in Icarus. http://dx.doi.org/10.1016/j.icarus.2014.01.030

For more information about Venus Express Mission, visit: http://www.esa.int/Our_Activities/Space_Science/Venus_Express

Images, Text, Credits: ESA / MPS / DLR / IDA / C. Wilson/P. Laven.

Greetings, Orbiter.ch

Space Station Crew Returns to Earth, Lands Safely in Kazakhstan











ROSCOSMOS - Soyuz TMA-10M Mission patch.

March 11, 2014

Three crew members from the International Space Station returned to Earth Monday after 166 days in space, during which they made 2,656 orbits around the planet and traveled almost 70.5 million miles

Expedition 38 crew members Michael Hopkins of NASA, and Oleg Kotov and Sergey Ryazanskiy of the Russian Federal Space Agency (Roscosmos) touched down southeast of the remote town of Dzhezkazgan, Kazakhstan, at about 11:24 p.m. EDT (9:24 a.m., March 11, in Dzhezkazgan).


Image above: The three member Expedition 38 crew rests outside after landing in the snowy steppe of Kazakhstan. Image Credit: ROSCOSMOS.

During Expedition 38, the crew members participated in a variety of research, including protein crystal growth studies and biological studies of plant seedling growth to technology demonstrations that are helping to improve our understanding of how liquid moves in microgravity. They conducted student experiments that observed celestial events in space. One of several key research focus areas during Expedition 38 was human health management for long duration space travel, as NASA and Roscosmos prepare for two crew members to spend one year aboard the space station in 2015.

During their time aboard the orbiting laboratory, the three men were there to welcome three visiting cargo spacecraft. Two Russian Progress crafts docked to the station, bringing tons of supplies. In January, Orbital Sciences Corp.'s Cygnus spacecraft loaded with cargo and experiments flew to the space station as part of the Orbital-1 cargo resupply mission. This was the company's first of at least eight cargo delivery flights through 2016 to the station under NASA's Commercial Resupply Services contract.


Image above: Flight controllers in the Russian mission control center in Korolev, Russia monitor the International Space Station Expedition 38 crew’s recovery after landing in Kazakhstan Monday at about 11:24 p.m. EDT. Image Credit: NASA Television.

Kotov, Ryazanskiy and Hopkins were on hand as Mastracchio, Mikhail Tyurin of Roscosmos and Koichi Wakata of the Japan Aerospace Exploration Agency arrived on Nov. 7, 2013, bearing the Olympic torch used to light the Olympic flame at Fisht Stadium in Sochi, Russia, which marked the start of the 2014 Winter Games in February.

Hopkins and fellow Expedition 38 NASA astronaut Rick Mastracchio ventured outside the confines of the space station during two spacewalks in December to replace a suspect ammonia pump that is part of the station's equipment cooling system. On the Russian side, Kotov and Ryazanskiy conducted three spacewalks. The first trip outside was to install and replace experiments and hardware attached to the exterior of the Russian segment and display the Olympic torch. The other two walks were to install a pair of cameras on the hull of the station's Zvezda Service Module that are part of a Canadian commercial endeavor with Roscosmos designed to downlink Earth-observation imagery to Internet-based subscribers.

Hopkins, who is a life-long enthusiast of exercise and weight training, participated last month with four fitness professionals and athletes in a Google+ Hangout from space where the astronaut discussed the importance of exercise in a weightless environment. He demonstrated one of the many pieces of fitness equipment aboard the station that crew use during their daily 2-hour workouts.

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Video above; Touchdown of Manned Soyuz TMA-10M Spacecraft in Kazakhstan. Video Credits: ROSCOSMOS TV / NASA TV.

The space station is more than a scientific research platform. It also serves as a test bed for technology demonstrations. During the past several months, the Expedition 38 crew members used the Synchronized Position Hold, Engage, Reorient, Experimental Satellites (SPHERES) for a number of investigations. These included demonstrating and testing techniques related to micro electromagnetic formation flight and wireless inductive power transfer; examining how liquids move around inside containers in microgravity, which affects computer simulations of liquid rocket fuel behavior and increases the safety and efficiency of future rockets; and demonstrating and testing enhanced technologies and techniques related to visual inspection and navigation. The crew members helped launch several miniature satellites, referred to as CubeSats, from the Japanese Experiment module. CubeSats are testing technologies ranging from Earth observation to smartphone technology to satellite attitude control in affordable small satellites that are within reach of most universities and even high- and middle- school students.

Ryazanskiy, Kotov and Hopkins also we aboard the orbital outpost when the Obama Administration announced in January NASA planned to extend the operational life of the International Space Station until at least 2024.

Hopkins and Ryazanskiy each now have 166 days in space after completing their first missions in space. Kotov now has spent 526 days in space on three flights.

Expedition 39 now is operating aboard the station. Koichi Wakata of the Japan Aerospace Exploration Agency, is in command of the orbiting laboratory. He is the first Japanese astronaut to hold this position. Wakata and his crewmates, Flight Engineers Mastracchio and Mikhail Tyurin of Roscosmos, will tend to the station as a three-person crew until the arrival in two weeks of three new crewmates: NASA astronaut Steve Swanson and Russian cosmonauts Alexander Skvortsov and Oleg Artemyev. Swanson, Skvortsov and Artemyev are scheduled to launch from Kazakhstan March 25.

For more information on the International Space Station and its crews, visit: http://www.nasa.gov/station

For video and other media resources, visit: http://www.nasa.gov/stationnews

Images (mentioned), Video (mentioned), Text, Credits: NASA / Joshua Buck / Johnson Space Center / Josh Byerly.

Cheers, Orbiter.ch

lundi 10 mars 2014

Expedition 38 Trio Undocks to Begin Short Ride Home











ROSCOSMOS - Soyuz TMA-10M Mission patch.

March 10, 2014

The Soyuz TMA-10 spacecraft carrying Soyuz Commander Oleg Kotov and Expedition 38 Flight Engineers Mike Hopkins and Sergey Ryazanskiy undocked from the Poisk module at 8:02 p.m. EDT. The trio will land about 3-1/2 hours later in Kazakhstan ending their mission after five-and-a-half months aboard the International Space Station.

Staying behind are new Expedition 39 Commander Koichi Wakata and Flight Engineers Rick Mastracchio and Mikhail Tyurin. The crew members arrived at the station’s Rassvet module Nov. 7 aboard a Soyuz TMA-11M spacecraft. They are scheduled to return home in mid-May. Wakata, a Japanese astronaut, is the Japan Aerospace Exploration Agency’s first station commander.


Image above: Expedition 38 crew members (from left) Mike Hopkins, Oleg Kotov and Sergey Ryazanskiy gather inside the Kibo laboratory for a crew portrait. Image Credit: NASA TV.

Kotov is completing his third mission aboard the orbital laboratory for a total of 526 days in space. He served as a flight engineer during Expedition 15 in 2007. He then served for six months as an Expedition 22/23 crew member beginning in December 2009.

Hopkins and Ryazanskiy are wrapping up their first space mission each accumulating 166 days in space. During his stay aboard the orbital laboratory, Hopkins conducted a pair of U.S. spacewalks for a total 12 hours and 58 minutes. Ryazanskiy conducted three Russian spacewalks during his mission working outside the station for 20 hours and five minutes.

Hopkins joined NASA astronaut Rick Mastracchio for the first pair of Expedition 38 spacewalks installing a new ammonia pump module to restore the station’s cooling system. The U.S. astronauts began the first spacewalk Dec. 21 exiting the Quest airlock to remove and stow a degraded pump module. They completed the installation of the new pump module during a second spacewalk on Dec. 24.

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Expedition 38 Hatch Closure

Video above: The hatches closed Monday at 4:58 p.m. EDT between the International Space Station and the docked Soyuz TMA-10M carrying Expedition 38 crew members Michael Hopkins, Soyuz Commander Oleg Kotov and Sergey Ryazanskiy. Video Credit: NASA TV.

Shortly after those excursions, Ryazanskiy and Kotov exited the Pirs docking compartment Dec. 27 to install photographic gear, route cables, remove completed external experiments and install new scientific gear. The duo went out a second time Jan. 27 to complete the photographic installation work, retrieve more science gear and enable robotic arm operations on the station’s Russian segment.

Kotov and Ryazanskiy’s first spacewalk occurred Nov. 9 when the duo handed off the Olympic torch in its first ever outer space portion of the relay. The torch was returned to Earth the next day and used to light the Olympic flame Feb. 7 at the 2014 Winter Olympic Games in Sochi, Russia.

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Expedition 38 ships off

Video above: Expedition 38 Commander Oleg Kotov, Michael Hopkins of NASA and Russian cosmonaut Sergey Ryazanskiy wrapped up a 166 day stay on the International Space Station when their Soyuz spacecraft undocked from the orbiting laboratory to begin their journey back to Earth. The undocking was covered by NASA Television.

Kotov has completed six spacewalks over his cosmonaut career accumulating 36 hours and 51 minutes outside the space station in a Russian Orlan spacesuit.

Waiting to replace the returning trio are Expedition 39/40 crew members Steve Swanson, Alexander Skvortsov and Oleg Artemyev. They are in Star City, Russia, completing mission training and making final preparations for their March 25 launch aboard a Soyuz TMA-12 spacecraft from Baikonur Cosmodrome, Kazakhstan.

The crew will execute a 4-minute, 50-second deorbit burn at 10:30 p.m. ahead of a landing at 11:24 p.m. southeast of Dzhezkazgan, Kazakhstan. Live NASA Television coverage begins at 10:15 p.m.: http://www.nasa.gov/multimedia/nasatv/index.html

For more information about International Space Station (ISS), visit: http://www.nasa.gov/mission_pages/station/main/index.html

Image (mentioned), Videos (mentioned), Text, Credit: NASA.

Best regards, Orbiter.ch

International Space Station to Beam Video via Laser Back to Earth












ISS - International Space Station patch.

March 10, 2014

What's more interesting than videos of cats chasing laser beams over the kitchen floor? How about videos sent OVER laser beams from NASA's International Space Station back to Earth?

A team of about 20 working at NASA's Jet Propulsion Lab in Pasadena, Calif., through the lab’s Phaeton early-career-hire program, led the development of the Optical Payload for Lasercomm Science (OPALS) investigation, which is preparing for a March 16 launch to the International Space Station aboard the SpaceX-3 mission. The goal? NASA’s first optical communication experiment on the orbital laboratory.

Scientific instruments used in space missions increasingly require higher communication rates to transmit gathered data back to Earth or to support high-data-rate applications, like high-definition video streams. Optical communications—also referred to as “lasercom”—is an emerging technology where data is sent via laser beams. This offers the promise of much higher data rates than what is achievable with current radio frequency (RF) transmissions and has the advantage that it operates in a frequency band that is currently unregulated by the Federal Communications Commission.


Image above: An artist's rendering shows the Optical Payload for Lasercomm Science (OPALS). Image Credit: OPALS.

"Optical communications has the potential to be a game-changer," said mission manager Matt Abrahamson. "Right now, many of our deep space missions communicate at 200 to 400 kilobits per second.” OPALS will demonstrate up to 50 megabits per second and future deep space optical communication systems will provide over one gigabits per second from Mars.

"It’s like upgrading from dial-up to DSL," added project systems engineer Bogdan Oaida. "Our ability to generate data has greatly outpaced our ability to downlink it. Imagine trying to download a movie at home over dial-up. It’s essentially the same problem in space, whether we’re talking about low-Earth orbit or deep space."

OPALS is scheduled to launch aboard a SpaceX Falcon 9 rocket, part of a cargo resupply mission to the space station. The payload will be inside the Dragon cargo spacecraft. Once deployed, OPALS will be conducting transmission tests for a period of nearly three months, with the possibility of a longer mission. After the Dragon capsule docks with the station, OPALS will be robotically extracted from the trunk of the Dragon, and then manipulated by a robotic arm for positioning on the station’s exterior. It is the first investigation developed at JPL to launch on SpaceX's Falcon rocket.


Image above: The Optical Payload for Lasercomm Science (OPALS) instrument is hoisted onto a shipping pallet for transfer to Kennedy Space Center in Florida. From there it will launch to the International Space Station. Image Credit: NASA.

The technology demo was conceived, developed, built and tested at JPL by engineers in the early stage of their careers in order to gain experience building space hardware and developing an end-to-end communication system. The system uses primarily commercial off-the-shelf hardware and encloses electronics in a pressurized container. "We were not as constrained by mass, volume or power on this mission as we were by cost," said Abrahamson, and this approach allowed a lower cost development on an efficient schedule.

As the space station orbits Earth, a ground telescope tracks it and transmits a laser beacon to the OPALS. While maintaining lock on the uplink beacon, the orbiting instrument’s flight system will downlink a modulated laser beam with a formatted video. Each demonstration, or test, will last approximately 100 seconds as the station instrument and ground telescope maintain line of sight. It will be used to study pointing, acquisition and tracking of the very tightly focused laser beams, taking into account the movement of the space station, and to study the characteristics of optical links through Earth’s atmosphere. NASA will also use OPALS to educate and train personnel in the operation of optical communication systems.

The success of OPALS will provide increased impetus for operational optical communications in NASA missions. The space station is a prime target for multi-gigabit per second optical links. Fast laser communications between Earth and spacecraft like the station or the Mars Curiosity rover would enhance their connection to engineers and scientists on the ground as well as to the public.

OPALS is a partnership between NASA’s Jet Propulsion Laboratory in Pasadena, Calif.; the International Space Station Program based at Johnson Space Center in Houston; Kennedy Space Center in Florida; Marshall Space Flight Center in Huntsville, Ala., and the Advanced Exploration Systems Division at NASA Headquarters in Washington.

Related links:

Optical Payload for Lasercomm Science (OPALS): http://www.nasa.gov/mission_pages/station/research/experiments/861.html

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

Images, Text, Credits: NASA / JPL / David Israel & Mark Whalen.

Greetings, Orbiter.ch

Rhea's Day in the Sun












NASA / ESA - Cassini Mission to Saturn patch.

March 10, 2014


A nearly full Rhea shines in the sunlight in this recent Cassini image. Rhea (949 miles, or 1,527 kilometers across) is Saturn's second largest moon.

Lit terrain seen here is on the Saturn-facing hemisphere of Rhea. North on Rhea is up and rotated 43 degrees to the left. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on Sept. 10, 2013.

The view was obtained at a distance of approximately 990,000 miles (1.6 million kilometers) from Rhea. Image scale is 6 miles (9 kilometers) per pixel.

Cassini around Saturn

The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. 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, Colo.

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

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

Greetings, Orbiter.ch

I spy… Rosetta’s comet












ESA - Rosetta Mission patch.

March 10, 2014

Comet Churyumov–Gerasimenko on 28 February 2014

On 20 January, ESA’s Rosetta spacecraft emerged from a 31-month hibernation on the final leg of its 10-year journey to comet 67P/Churyumov–Gerasimenko. Just like the spacecraft, the mission’s target is also now emerging from hibernation.

For the last few months, the comet has been behind the Sun from our vantage point on Earth. But in late February, the Very Large Telescope of the European Southern Observatory in Chile resumed observations – its last look was on 5 October 2013.

The image presented here was taken on the night of the 27 February (09:30 GMT on 28 February). The image on the left was created by stacking individual exposures to show the background stars. These were then shifted to compensate for the motion of the comet, which appears as a small dot right on top of one of the stars (at the centre of the circle). The image on the right shows the comet when the star trails have been subtracted.

The observatory is collaborating with ESA to monitor the four kilometre-wide comet from the ground to help refine Rosetta’s navigation and to make assessments of the comet’s activity prior to the spacecraft’s arrival in August.

Rosetta Wake Up! Rosetta arrives at Comet 67P

The comet is about 50% brighter than when it was last observed. Although it is also now nearer to Earth, it has brightened faster than expected for an inactive comet of this size, suggesting that its icy nucleus has started to evaporate as it moves gradually closer to the Sun.

The comet travels around the Sun between the orbits of Jupiter and Earth; its closest approach to the Sun, in August 2015, is at a distance of 185 million kilometres.

Rosetta will be the first mission to make continuous measurements at close-quarters of how a comet’s activity changes as it journeys around the Sun.

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

Image, Text, Credits: ESA / ESO / C. Snodgrass (Max Planck Institute for Solar System Research, Germany) & O. Hainaut (ESO) / Video: Orbiter.ch Aerospace Studio.

Cheers, Orbiter.ch