Quintet of moons

NASA / ESA - Cassini Mission to Saturn patch.

Nov. 4, 3013

Five moons pose for the international Cassini spacecraft to create this beautiful portrait with Saturn’s rings.

This view, from 29 July 2011, looks toward the northern, sunlit side of the rings from just above the ringplane.

At the far right, and obscuring Saturn itself, is the planet’s second largest moon Rhea, which spans 1528 km. Rhea is closest to Cassini in this composition, at a distance of 1.1 million kilometres. Its heavily cratered surface bears witness to a violent history, with many craters overlapping or erasing the traces of older impact events.

The nearly 400 km-wide Mimas lies just beyond, and seemingly levitates just above Saturn’s innermost rings. The outline of the moon’s large, distinguishing crater Herschel is partially covered by Rhea, but can just be made out along with numerous smaller craters.

Brightly reflective Enceladus appears above the centre of the image and lies beyond the rings, at a distance of 1.8 million kilometres from Cassini. Although not visible in this image, icy Enceladus is covered with a network of frozen ridges and troughs, with plumes of ice particles jetting from fissures in its southern hemisphere.

To the lower left, tiny Pandora, just 81 km across, appears skewered by Saturn’s outer rings – in fact, it orbits between the planet’s A and F rings.

Last but not least, the irregularly shaped Janus lies at the far left of the image, several shadowy surface markings corresponding to large impact craters.

The Cassini–Huygens mission is a cooperative project of NASA, ESA and ASI, 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, Washington DC, USA.

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

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

Best regards, Orbiter.ch

Proba-2 views hybrid eclipse

ESA - Proba-2 Mission logo.

Nov. 4, 2013

Proba-2 views hybrid eclipse

Three partial solar eclipses are seen in this movie from ESA’s Proba-2 Sun-watching satellite as it dipped in and out of the Moon’s shadow during yesterday’s ‘hybrid’ solar eclipse.

A hybrid eclipse comprises a total solar eclipse and an ‘annular eclipse’, depending on an observer’s viewing location on Earth.

During a total solar eclipse, the Moon moves in front of the Sun as seen from Earth, their alignment and separation such that the much closer Moon appears large enough to block out the light from the much more distant Sun.

Proba-2 spacecraft

But from some locations, the apparent size of the Moon is slightly smaller than that of the Sun, leaving a bright ring around the dark disc of the Moon.

Meanwhile, from its vantage point in Earth orbit, Proba-2 saw several partial eclipses.

Proba-2 orbits Earth about 14.5 times per day, dipping in and out of the Moon’s shadow around the time of a solar eclipse.

The video was produced from images taken by Proba-2’s SWAP imager, which snaps the Sun in ultraviolet light. Stormy active regions on the Sun’s face are revealed, including sunspots, the roots of some large solar flares and ‘coronal mass ejections’ that are occasionally directed towards Earth.

Related links:

Proba-2: http://www.esa.int/SPECIALS/Proba/index.html

ROB Proba-2 science centre: http://proba2.sidc.be/index.html/

Image, Video, Text, Credit: ESA.

Greetings, Orbiter.ch

Moon mission beams laser data to ESA station

ESA - European Space Agency patch / NASA - LADEE Mission patch.

2 November 2013

ESA’s ground station on the island of Tenerife has received laser signals over a distance of 400 000 km from NASA’s latest Moon orbiter. The data were delivered many times faster than possible with traditional radio waves, marking a significant breakthrough in space communications.

The Lunar Atmosphere and Dust Environment Explorer, or LADEE, was launched on 7 September and arrived in orbit around the Moon in October. In addition to probing the Moon’s environment, it’s also carrying a new laser terminal.

Focal spot: laser light seen by infrared camera

This new approach promises data speeds far superior to traditional radio waves used today by satellites and ground stations, including the Agency’s Estrack network.

ESA’s Optical Ground Station in Spain’s Canary Islands was upgraded with an advanced laser terminal developed in Switzerland and Denmark that can communicate with LADEE using highly focused beams.

“We acquired the first signals from LADEE on 26 October, and since then, we’ve had a series of optical uplinks and downlinks providing extremely fast laser communications,” says Zoran Sodnik, ESA’s project manager for the laser effort.

“We’ve already received data at up to 40 Mbit/s – several times faster than a typical home broadband connection.”

Tenerife station

The contact with Tenerife came just days after LADEE made history on 18 October in the first-ever laser transmission from lunar orbit, picked up by a NASA station at White Sands, New Mexico, USA. The craft is also transmitting to a third station, at NASA’s Jet Propulsion Laboratory in California.

Laser communications at near-infrared wavelengths may be the way of the future when it comes to downloading massive amounts of data from spacecraft orbiting Earth, Mars or even more distant planets.

Laser communication units are lighter and smaller than today’s onboard radio systems, promising to cut mission costs and provide opportunities for new science payloads.

 “The participation of the ESA ground terminal at Tenerife in NASA’s project is an important milestone in this new capability,” said Badri Younes, deputy associate administrator for space communications and navigation at NASA’s Headquarters in Washington DC.

“Together, we have demonstrated at the very beginning of the optical communication era the value of interoperable communication between our space agencies.”

With the first two communication passes with LADEE on 26 October and six more to 29 October, the ESA team on Tenerife are tweaking the station hardware – especially for the uplink – and improving procedures.

LADEE transmits laser signal

“Some initial difficulties with the extremely accurate pointing necessary for laser communication are being investigated, but this is quite normal at this stage,” says ESA’s Klaus-Juergen Schulz, responsible for ground station systems at the European Space Operations Centre, Darmstadt, Germany.

“We are already confident that the test campaign will confirm the practicality of high-data-rate optical links for future missions.”

During the coming weeks, ESA engineers will test uplink communications at 20 Mbit/s and obtain accurate ‘time-of-travel’ measurements to be used for calculating the spacecraft’s orbit.

Using special equipment from the DLR German Aerospace Center’s Institute for Communication and Navigation, the team will monitor atmospheric conditions during transmission and learn how to improve performance even further.

More information on the laser communication project: http://www.esa.int/Our_Activities/Operations/More_information_-_laser_communication_project

Related links:

Laser communication project: http://www.esa.int/Our_Activities/Operations/More_information_-_laser_communication_project

NASA Laser Communication System Sets Record: http://www.nasa.gov/press/2013/october/nasa-laser-communication-system-sets-record-with-data-transmissions-to-and-from/#.UnPQTSfHhiw

General Support Technology Programme (GSTP): http://www.esa.int/Our_Activities/Technology/About_the_General_Support_Technology_Programme_GSTP

ESOC - European Space Operations Centre: http://www.esa.int/About_Us/ESOC

Optical Communication: http://www.esa.int/Our_Activities/Telecommunications_Integrated_Applications/Alphasat/Optical_Communication

NASA Ladee mission: http://www.nasa.gov/mission_pages/LADEE/main/

Images, Text, Credits: ESA / NASA.

Best regards, Orbiter.ch

A fiery end to a perfect mission: ATV Albert Einstein

ESA - ATV-4 Albert Einstein Mission patch.

2 November 2013

 ATV-4 over Earth

ESA’s fourth Automated Transfer Vehicle cargo ferry, Albert Einstein, completed its five-month mission to the International Space Station by reentering the atmosphere today and burning up safely over an uninhabited area of the southern Pacific Ocean.

Automated Transfer Vehicles (ATVs) are the most complex space vehicles ever developed in Europe and are the largest and most capable resupply ships to dock with the Space Station.

ATV-4 launch

At 20 tonnes, ATV-4 set the record for the heaviest Ariane 5 launch when its mission started from Europe’s Spaceport in French Guiana on 5 June, docking with the Station 10 days later. The record cargo of 2480 kg included more than 1400 individual items.

Albert Einstein delivered important cargo to keep the Station operating and to allow the six astronauts on the orbital outpost to perform out-of-this-world experiments.

ESA astronaut Luca Parmitano oversaw the automated docking and was responsible for unloading and storing all the scientific equipment, spare parts, supplies, clothes and food.

Unloading ATV-4

A small selection of ATV-4’s cargo includes experiments on emulsions that will help industry to create foods and pharmaceuticals with longer shelf-lives, a replacement water pump for Europe’s Columbus laboratory, a new water recycler for NASA, a GPS antenna for Japan’s Kibo laboratory and 3D-printed space toolboxes.

While docked, ATV-4 performed six reboosts to keep the Space Station in orbit, counteracting the effects of atmospheric drag. Without reboosts by ATV and Russia’s smaller Progress vehicles, the Station would eventually fall back to Earth.

Before its departure, astronauts loaded its pressurised module with waste material, freeing up space on the Station. After setting records going up, ATV-4 also set records on its descent: it had the most waste material loaded for the series. 

ATV-4 undocking

The European ferry undocked on 28 October at 08:55 GMT (09:55 CET) and manoeuvred itself into a safe reentry trajectory about 100 km below the Station.

Albert Einstein performed a series of delicate manoeuvres to reenter below the Station in order for the astronauts to observe the spacecraft’s fragmentation in the upper atmosphere, providing unique information on reentry physics.

ATV-4 and its waste burnt up harmlessly in the upper atmosphere on 2 November at 12:04 GMT (13:04 CET).

ATV-4 free flight

ATV's perform all their manoeuvres, including their autonomous dockings, under close surveillance by their control centre in Toulouse, France, run jointly by ESA and France’s CNES space agency.

“The mission went perfectly, which for me and the ATV team or any space mission is a great thing,” says Alberto Novelli, ATV-4 mission manager.

“The smooth running of this fourth mission shows the maturity of the ATV programme and puts ESA’s successful track record on the map for future projects.”

ATV Control Centre

The next spacecraft in the series, ATV Georges Lemaître, has already arrived by boat at the European spaceport in French Guiana. Loading cargo into the pressurised module will start in March next year. ATV-5’s modules will then be combined and placed on its Ariane launcher for launch at the end of June.

With the series of five ATV space vehicles, ESA will have paid its dues for using the Station through to the end of 2017.

ATV-4 docked to Zvezda

ESA is contributing a significant share of the maintenance of the Station to cover the costs related operating its own elements – the Columbus laboratory and its set of experiments and related science equipment – as well as to the regular flights of its astronauts.

Related links:

Automated Transfer Vehicle: http://www.esa.int/Our_Activities/Human_Spaceflight/ATV

ATV Control Centre: http://www.esa.int/Our_Activities/Human_Spaceflight/ATV/ATV_Control_Centre

Ariane 5: http://www.esa.int/Our_Activities/Launchers/Launch_vehicles/Ariane_5

Images, Text, Credits: ESA / S. Corvaja / J. Harrod / NASA.

Greetings, Orbiter.ch

Comet Ison Roars Through Leo

Asteroid and comet watch.

Nov. 1, 2013

In the early morning of Oct. 25 (6:45 a.m. EDT), NASA's Marshall Space Flight Center in Huntsville, Ala., used a 14" telescope to capture this image of Comet C/2012 S1 (ISON), which is brightening as it approaches the sun. The comet shines with a faint green color just to the left of center. The diagonal streak right of center was caused by the Italian SkyMed-2 satellite passing though the field of view. At magnitude 8.5, the comet is still too faint for the unaided eye or small binoculars, but it's an easy target in a small telescope.

At this time of this image, ISON was located in the constellation of Leo the Lion, some 132 million miles from Earth and heading in toward the sun at 87,900 miles per hour.

For images and more information about comet ISON, visit: http://www.nasa.gov/cometison

Image, Text, Credit: NASA / MSFC / Aaron Kingery.

Cheers, Orbiter.ch

Hubble's New Shot of Proxima Centauri, our Nearest Neighbor

NASA - Hubble Space Telescope patch.

Nov. 1, 2013

Shining brightly in this Hubble image is our closest stellar neighbor: Proxima Centauri.

Proxima Centauri lies in the constellation of Centaurus (The Centaur), just over four light-years from Earth. Although it looks bright through the eye of Hubble, as you might expect from the nearest star to the Solar System, Proxima Centauri is not visible to the naked eye. Its average luminosity is very low, and it is quite small compared to other stars, at only about an eighth of the mass of the sun.

However, on occasion, its brightness increases. Proxima is what is known as a flare star," meaning that convection processes within the star’s body make it prone to random and dramatic changes in brightness. The convection processes not only trigger brilliant bursts of starlight but, combined with other factors, mean that Proxima Centauri is in for a very long life. Astronomers predict that this star will remain middle-aged — or a "main sequence" star in astronomical terms — for another four trillion years, some 300 times the age of the current Universe.

These observations were taken using Hubble’s Wide Field and Planetary Camera 2 (WFPC2). Proxima Centauri is actually part of a triple star system — its two companions, Alpha Centauri A and B, lie out of frame.

Although by cosmic standards it is a close neighbor, Proxima Centauri remains a point-like object even using Hubble’s eagle-eyed vision, hinting at the vast scale of the Universe around us.

Notes:

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

For more information about Hubble Space Telescope, visit: http://www.spacetelescope.org/ and http://hubblesite.org/

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

Greetings, Orbiter.ch

Soyuz Move Sets Stage for Arrival of New Crew

ISS - International Space Station patch.

Nov. 1, 2013

Three International Space Station crew members took their Soyuz for a spin around the block Friday as they prepare for the extremely busy final week of Expedition 37.

Image above: The Soyuz TMA-09M under the command of Expedition 37 Commander Fyodor Yurchikhin backs away from the International Space Station's Rassvet module for a flyaround to the aft port of the Zvezda service module. Image Credit: NASA TV.

Commander Fyodor Yurchikhin and Flight Engineers Karen Nyberg and Luca Parmitano undocked their Soyuz TMA-09M spacecraft from the Rassvet module on the Earth-facing side of the station at 4:33 a.m. EDT Friday. After backing the vehicle a safe distance away, Soyuz Commander Yurchikhin rotated the Soyuz and began the flyaround to the rear of the station. Carefully aligning the spacecraft with the docking port on the aft end of the Zvezda service module, which was vacated by the European Space Agency’s fourth Automated Transfer Vehicle (ATV) on Monday, Yurchikhin guided the spacecraft in for its docking at 4:54 a.m.

Russian Soyuz Vehicle Relocates at the International Space Station

Video above: The Russian Soyuz TMA-09M spacecraft, with Commander Fyodor Yurchikhin and Flight Engineers Karen Nyberg and Luca Parmitano aboard, changes parking spaces at the International Space Station Nov. 1.

Coincidentally, Yurchikhin was at the helm for the last Soyuz relocation at the station in June 2010 when he piloted the Expedition 24 crew’s Soyuz TMA-19 vehicle from Zvezda to the then newly installed Rassvet module.

Friday’s Soyuz move sets the stage for the launch and arrival of a trio of new station crew members -- NASA astronaut Rick Mastracchio, Japan Aerospace Exploration Agency astronaut Koichi Wakata and Soyuz Commander Mikhail Tyurin of the Russian Federal Space Agency – who will dock their Soyuz TMA-11M spacecraft to Rassvet on Nov. 7 about six hours after their launch from the Baikonur Cosmodrome in Kazakhstan.

The arrival of Mastracchio, Wakata and Tyurin will mark the first time since October 2009 that nine people have served together aboard the station without the presence of a space shuttle.

Also arriving to the station aboard the Soyuz TMA-11M will be the Olympic torch, which is making the longest leg of its relay leading up to the 2014 Winter Olympics in Sochi, Russian. Flight Engineers Oleg Kotov and Sergey Ryazanskiy will take the Olympic torch outside the station during a symbolic spacewalk.

While their crewmates relocated the Soyuz spacecraft Friday, Kotov and Ryazanskiy consolidated their tool caddies for the upcoming spacewalk. Their excursion, which is slated to begin on Nov. 9 at 9:30 a.m. EST, will air live on NASA TV.

The torch will return to Earth along with Yurchikhin, Nyberg and Parmitano on Nov. 10 when they board their Soyuz for the journey home after more than five months in space.

The final departure of Yurchikhin, Nyberg and Parmitano will free the Zvezda port for the docking of a new Progress resupply vehicle in late November. Program managers prefer to have a Progress or ATV cargo ship docked at Zvezda so it can help reboost the station and adjust its attitude.

Image above: NASA astronaut Michael Hopkins, Expedition 37 flight engineer, enters data in a computer in the Harmony node of the International Space Station. Image Credit: NASA.

Flight Engineer Mike Hopkins meanwhile spent much of his Friday morning setting up the Advanced Biological Research System (ABRS).  The NASA astronaut assembled a reference grid, flushed the system’s cooling loop, installed two new memory cards and powered up the system for a ground-based checkout of telemetry. The ABRS contains two temperature-controlled chambers that can be used to grow plants, microorganisms and small arthropods, such as insects or spiders.

Read more about ABRS: http://www.nasa.gov/mission_pages/station/research/experiments/ABRS.html

Hopkins also recharged batteries for an upcoming session with a set of soccer-ball-sized, free-flying satellites known as Synchronized Position Hold, Engage, Reorient, Experimental Satellites, or SPHERES. Surrounding each SPHERES mini-satellite for this next test will be ring-shaped hardware known as the Resonant Inductive Near-field Generation System, or RINGS, which will be used to demonstrate how power can be transferred between satellites without physical contact.

SPHERES mini-satellites

Read more about SPHERES-RINGS: http://www.nasa.gov/mission_pages/station/research/experiments/916.html

Over the weekend, all six station residents will get a chance to recharge their own batteries as they enjoy some free time, take care of housekeeping tasks throughout the station and get ready for the final week of Expedition 37.

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

Images, Video, Text, Credits: NASA / NASA TV.

Best regards, Orbiter.ch