vendredi 23 octobre 2015

NASA Analyzes Record-Breaking Hurricane Patricia












NASA - Goddard Space Flight Center logo.

Oct. 23, 2015

Patricia (Eastern Pacific)

NASA satellites and instruments have been monitoring the record-breaking Hurricane Patricia as it rapidly intensified off the southwestern coast of Mexico on October 23. NASA-NOAA's Suomi NPP saw frigid cloud top temperatures, NOAA's GOES-West satellite provided imagery and animations that showed the extent of the storm, NASA's Terra satellite provided visible data, and the RapidScat instrument aboard the International Space Station measured its surface winds


Image above: When NASA-NOAA's Suomi NPP satellite passed over Patricia on October 23 at 5:20 a.m. EDT the VIIRS instrument that flies aboard Suomi NPP looked at the storm in infrared light. Cloud top temperatures of thunderstorms around the eyewall were between 180K (-135.7F/ -93.1C) and 190 Kelvin (-117.7F/ -83.1C). Image Credits: UW/CIMSS/William Straka III.

Suomi NPP Satellite Sees Frigid High Clouds

When NASA-NOAA's Suomi NPP satellite passed over Patricia on October 23 at 5:20 a.m. EDT the Visible Infrared Imaging Radiometer Suite or VIIRS instrument that flies aboard Suomi NPP looked at the storm in infrared light. "Cloud top temperatures of thunderstorms around the eyewall were between 180K (-135.7F/ -93.1C) and 190 Kelvin (-117.7F/ -83.1C)," said William Straka III of the University of Wisconsin, Madison. "Then, as you go into the eye itself, it gets warmer."

The higher the cloud tops, the colder they are as temperatures get colder with altitude in the troposphere. Storms with cloud top temperatures that cold have the capability of generating heavy rainfall.

video
Satellite Movie Sees Record-Breaking Hurricane Patricia

Video above: At 8 a.m. EDT on October 23, 2015, the National Hurricane Center reported Patricia became the strongest eastern north pacific hurricane on record with sustained winds near 200 mph. This animation of images captured from October 20 to 23 from NOAA's GOES-West satellite shows Hurricane Patricia near western Mexico. Video Credits: NASA/NOAA GOES Project.

GOES Satellite Animation Shows Rapid Intensification

On October 22, Patricia was a Category one hurricane. By 8 a.m. EDT on October 23, 2015, the National Hurricane Center reported Patricia became the strongest eastern north pacific hurricane on record with sustained winds near 200 mph.

An animation of images captured from October 20 to 23 from NOAA's GOES-West satellite showed Hurricane Patricia intensify within 24 hours and develop a clear eye near the coast of western Mexico.  The animation was created at NASA/NOAA GOES Project at NASA's Goddard Space Flight Center, Greenbelt, Maryland.


Image above: On Oct. 23 at 17:30 UTC (1:30 p.m. EDT) NASA's Terra satellite saw the eastern quadrant of Hurricane Patricia over Mexico and the storm's pinhole eye. Image Credits: NASA's Goddard MODIS Rapid Response Team.

NASA's Terra Satellite Sees Northeastern Quadrant Already Over Mexico

On Oct. 23 at 17:30 UTC (1:30 p.m. EDT) the Moderate Resolution Imaging Spectroradiometer instrument aboard NASA's Terra satellite saw the eastern quadrant of Hurricane Patricia over Mexico and the storm's pinhole eye.

Watches and Warnings on October 23, 2015

A Hurricane Warning is in effect from San Blas to Punta San Telmo and a Hurricane Watch is in effect from east of Punta San Telmo to Lazaro Cardenas. A Tropical Storm Warning is in effect from east of Punta San Telmo to Lazaro Cardenas and north of San Blas to El Roblito.

Two Records Broken

The National Hurricane Center reported that Patricia is the strongest hurricane on record in the National Hurricane Center's area of responsibility (AOR) which includes the Atlantic and the eastern North Pacific basins. The minimum central pressure estimated from the aircraft data, 880 millibars, is the lowest ever for our AOR. The National Hurricane Center noted "It seems incredible that even more strengthening could occur before landfall later today [October 23]. The official forecast shows only a little more strengthening before landfall."


Image above: This visible image of Hurricane Patricia was taken from NOAA's GOES-West satellite at 1745 UTC (1:45 p.m. EDT) as it headed for landfall along the western coast of Mexico. Image Credits: NASA/NOAA GOES Project.

Status of Hurricane Patricia on October 23 at 2 p.m. EDT

At 2 p.m. EDT (1800 UTC) on October 23, the center of Hurricane Patricia was located near latitude 18.2 North, longitude 105.3 West. Patricia was moving toward the north near 12 mph (19 kph).  On the forecast track, the center of Patricia should cross the coast in the hurricane warning area during the next several hours. After landfall, the center of Patricia is expected to move quickly north-northeastward across western and northern Mexico.

Reports from a NOAA Hurricane Hunter aircraft indicate that maximum sustained winds remain near 200 mph (325 kph) with higher gusts. Patricia is a category 5 hurricane on the Saffir-Simpson Hurricane.

video
International Space Station Footage of Hurricane Patricia

Video above: Outside the International Space Station, cameras captured dramatic views of Hurricane Patricia at 12:15 p.m. EDT on October 23, 2015 as the mammoth system moved north at about 10 mph, heading for a potentially catastrophic landfall along the southwest coast of Mexico sometime during the day, according to the National Hurricane Center. Packing winds of 200 miles per hour, Patricia is the strongest in recorded history in the southeastern Pacific Ocean. The National Hurricane Center says that once Patricia crosses the Mexican coast it should weaken quickly and dissipate Oct. 24 due to upper level winds and mountainous terrain, but likely will introduce copious amounts of rainfall to the Texas coast through the weekend. Video Credit: NASA TV.

Wind Scale. Patricia is expected to remain an extremely dangerous category 5 hurricane through landfall.  After landfall, Patricia is forecast to rapidly weaken over the mountains of Mexico. Hurricane force winds extend outward up to 35 miles (55 km) from the center and tropical storm force winds extend outward up to 175 miles (280 km). The minimum central pressure estimated from the NOAA aircraft data was 879 millibars.

Landfall Expected at Night, October 23/Early October 24 as a Category 5

Forecaster Beven of the National Hurricane Center stated in a discussion that Patricia is expected to make landfall as a Category 5 hurricane in southwestern Mexico in less than 12 hours.  After landfall, a combination of the mountainous terrain of Mexico and increasing shear should cause the cyclone to rapidly weaken, with the system likely to dissipate completely after 36 hours.

Despite dissipation, the National Hurricane Center said that development of another low pressure area is expected to draw significant amounts of moisture from Patricia's remnants, and could result in locally heavy rainfall over portions of the northwestern Gulf of Mexico coastal area within the next few days.

For updated forecasts, watches and warnings, visit: http://www.nhc.noaa.gov

For more information about Suomi NPP satellite mission, visit: http://npp.gsfc.nasa.gov/

For more information about GOES-West satellite mission, visit: http://www.goes.noaa.gov/goes-w.html

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

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

Greetings, Orbiter.ch

20 Intriguing Exoplanets










Exoplanets - Many Worlds logo.

Oct. 23, 2015

In celebration of the 20th anniversary of the first confirmed planet around a sun-like star, more than 60 leaders in the field of exoplanet observations chose their favorites among the nearly 2,000 known exoplanets. Some of the exoplanets are rocky, some are gaseous, and some are very, very odd. But there's one thing each one of these strange new worlds has in common: All have advanced scientific understanding of our place in the cosmos.

Check out the astronomers' top 20 list of exoplanets below, along with artist's concepts depicting what they might look like.

1. Kepler-186f

 
Image above: Kepler-186f was the first rocky planet to be found within the habitable zone -- the region around the host star where the temperature is right for liquid water. This planet is also very close in size to Earth. Even though we may not find out what's going on at the surface of this planet anytime soon, it's a strong reminder of why new technologies are being developed that will enable scientists to get a closer look at distant worlds. Image Credits: NASA Ames/SETI Institute/JPL-Caltech.

2. HD 209458 b (nickname "Osiris")


Image above: The first planet to be seen in transit (crossing its star) and the first planet to have it light directly detected. The HD 209458 b transit discovery showed that transit observations were feasible and opened up an entire new realm of exoplanet characterization. Image Credits: NASA, European Space Agency, Alfred Vidal-Madjar (Institut d'Astrophysique de Paris, CNRS).

3. Kepler-11 system


Image above: This was the first compact solar system discovered by Kepler, and it revealed that a system can be tightly packed, with at least five planets within the orbit of Mercury, and still be stable. It touched off a whole new look into planet formation ideas and suggested that multiple small planet systems, like ours, may be common. Image Credits: NASA/JPL-Caltech.

4. Kepler-16b


Image above: A real-life "Tatooine," this planet was Kepler's first discovery of a planet that orbits two stars -- what is known as a circumbinary planet. Image Credits: NASA/JPL-Caltech.

5. 51 Pegasi b


Image above: This giant planet, which is about half the mass of Jupiter and orbits its star every four days, was the first confirmed exoplanet around a sun-like star, a discovery that launched a whole new field of exploration. Image Credits: NASA/JPL-Caltech.

6. CoRoT 7b  


Image above: The first super-Earth identified as a rocky exoplanet, this planet proved that worlds like the Earth were indeed possible and that the search for potentially habitable worlds (rocky planets in the habitable zone) might be fruitful. Image Credits: ESO/L. Calçada.

7. Kepler-22b 


Image above: A planet in the habitable zone and a possible water-world planet unlike any seen in our solar system. Image Credits: NASA/Ames/JPL-Caltech.

8. Kepler-10b  


Image above: Kepler's first rocky planet discovery is a scorched, Earth-size world that scientists believe may have a lava ocean on its surface. Image Credits: NASA/Kepler Mission/Dana Berry.

9. Kepler-444 system


Image above: The oldest known planetary system has five terrestrial-sized planets, all in orbital resonance. This weird group showed that solar systems have formed and lived in our galaxy for nearly its entire existence. Image Credits: Tiago Campante/Peter Devine.

10. 55 Cancri e 


Image above: 55 Cancri e is a toasty world that rushes around its star every 18 hours. It orbits so closely -- about 25 times closer than Mercury is to our sun -- that it is tidally locked with one face forever blisters under the heat of its sun. The planet is proposed to have a rocky core surrounded by a layer of water in a "supercritical" state, where it is both liquid and gas, and then the whole planet is thought to be topped by a blanket of steam. Image Credits: NASA/JPL-Caltech.

11. HD 189733 b


Image above: This exoplanet, about the size of Jupiter, is one of the most studied exoplanets and is the first caught passing in front of its parent star in X-rays. NASA’s Chandra X-ray Observatory and the European Space Agency’s XMM Newton Observatory have been used to observe a dip in X-ray intensity as HD 189733b transits its parent star. Image Credits: NASA/ESA/G. Bacon (STScI).

12. PSR B1257+12 system


Image above: Discovered in 1992 and 1994, the planets that orbit pulsar PSR B1257+12 are not only the smallest planetary bodies known to exist outside our solar system, they also orbit a neutron star. These weird "pulsar planets" demonstrated that planets exist in all environments in the galaxy -- even around the remnants of an exploded star. Image Credits: NASA/JPL-Caltech.

13. K2-3



Images above: Three super-Earths discovered by the K2 mission orbiting a nearby star. Their mass and radius are already known and soon they may reveal their atmospheric composition. Image Credits: ESO/M. Kornmesser/Nick Risinger/ L. Calcada.

14. HR 8799 


Image above: The first directly imaged multi-exoplanet system. This system contains a debris disk and at least four massive planets. Image Credits: NRC-HIA, Christian Marois, Keck Observatory.

15. Kepler-36 system


Image above: The two known planets in this system have the most closely spaced orbits ever confirmed. On their closest approach, the neighboring duo comes within about 1.2 million miles of each other -- only five times the Earth-moon distance. Image Credits: ESO.

16. HD 114762 b


Image above: Discovered in 1989, three years prior to the pulsar planets and six years prior to 51 Peg b, HD 114762 b is truly the first discovered planet around a sun-like star. However, because its mass is 11 times that of Jupiter and was found in an orbit of 84 days, it was initially assumed (incorrectly) to be a brown dwarf. Image Credits: NASA/JPL-Caltech.

17. Kepler-452b


Image above: This world is the first Earth-sized planet found in the habitable zone of a sun-like star. The planet is 60 percent larger than Earth and 5 percent farther from its parent star than Earth is from the sun. Image Credits: NASA/Ames/JPL-Caltech.

18. HD 80606 b


Image above: This world has the most eccentric orbit, and as one scientist put it, "wears its heart on its sleeve," with storms, rotation, atmospheric heating, and a crazy orbit all plainly visible. Image Credits: NASA/JPL-Caltech/ UCSC.

19. WASP-47 


Image above: Part of a compact multi-planet system, it's the only known hot Jupiter with close planetary companions. Image Credits: NASA/JPL-Caltech.

20. OGLE-2005-BLG-390 


Image above: Part of a compact multi-planet system, it's the only known hot Jupiter with close planetary companions. Image Credits: NASA/JPL-Caltech.

NASA’s Jet Propulsion Laboratory, in Pasadena, manages NASA's Exoplanet Exploration program office. More information about exoplanets and NASA's planet-finding program is at http://planetquest.jpl.nasa.gov . Caltech manages JPL for NASA.

Images (mentioned), Text, Credits: NASA/Tony Greicius/JPL/Whitney Clavin.

Best regards, Orbiter.ch

CALET aboard the ISS Kibo Started the First Direct Electron Observation








JAXA - Kibo Module logo.

October 23, 2015

CALorimetric Electron Telescope (CALET) aboard the ISS "Kibo" Started the First Direct Electron Observation in Tera Electron Volt Region


Image above: Figure 1: Electron (candidate) event image in the TeV region observed on Oct. 14 during the initial verification and data calibration (presented by particle number converted from pulse height).

Figure 1 shows a high-energy cosmic ray (electron candidate) incoming to the calorimeter observed by three instruments of the calorimeter (CHD: Charge Detector, IMC: Imaging Calorimeter, and TASC: Total Absorption Calorimeter).
Based on the number of shower particles (that is proportional to energy) detected by each sensor, the image indicates the process that cosmic rays coming from above was generating shower particles within the calorimeter in colors from blue (low) to red (high).

With this kind of imagingtechnology of cosmic rays, we can determine the type (electrons, gamma-rays, proton/atomic nucleus), the incoming direction and the energy.

The left figure is an image viewed from the X-direction, and the right one is from the Y-direction. Using them both, 3D data processing becomes possible.

CALET is an observation instrument equipped with cutting-edge detectors and electronic technology to perform very high precision observations of extremely high-energy electrons, gamma-rays, protons and atomic nucleus, which have been difficult to perform to date, and also measure gamma-ray burst phenomena. Through the CALET observations, we are aiming at elucidating cosmic / universal mysteries including 1) origin and acceleration mechanism of high-energy cosmic rays, 2) diffusion mechanism of cosmic rays within the Galaxy, and 3) dark matter signature.

CALET was transported to Kibo by the KOUNOTORI5 launched from the Tanegashima Space Center in August 2015 to be installed on the Kibo's Exposed Facility. After completing the initial verification of observation instruments, CALET is now under calibration and verification of detected data. In the early stage of the verification process, the TeV electrons (candidates) have already been observed as shown in the previous page.
CALET will move to regular observation mode after data calibration and verification to perform high-precision observations for over two years. We will achieve our observation goals through statistical processing with fewer errors.


Image above: Figure 2: Event image acquired at higher sensitivity (above) and lower sensitivity (bottom).

It is the raw data for the event image of electrons (candidates) in the TeV region shown in Figure 1 on the previous page.

- CALET

CALET (CALorimetric Electron Telescope) is a mission instrument to observe high-energy cosmic rays in space. CALET is installed on the Exposed Facility of the Japanese Experiment Module "Kibo" at the International Space Station (ISS). It is a joint research project of JAXA and Waseda University led by Professor Shoji Torii (Faculty of Science and Engineering, Waseda University). Among the Japanese team, 22 research institutes such as Kanagawa University, Aoyama Gakuin University, and the Institute for Comic Ray Research, University of Tokyo, are also participating in this project.

In addition, NASA and the Italian Space Agency (Agenzia Spaziale Italiana, ASI) cooperated to develop CALET. NASA and American researchers provided us with technical support for the cosmic rays observation sensor technology, while ASI and Italian researchers assisted us with high-voltage power and cosmic rays observation sensor technology. Both of them will mutually cooperate in analyzing CALET observation data.

- Calorimeter aboard CALET
The calorimeter that can detect positions of shower particles is installed on CALET. The calorimeter was developed under the cooperation of Japan, NASA and ASI by carrying out beam tests of a CALET proto-type model at the European Organization for Nuclear Research (CERN). By imaging the "shower particles" that are generated by cosmic rays within the calorimeter, high energy cosmic rays can be observed precisely.

The calorimeter is an instrument to measure the energy of high-energy particles. When an electron or gamma-ray passes through a matter, electromagnetic interactions, such as bremsstrahlung and electron-positron pair creation, occurs successively and increases particles (cascade shower). The calorimeter is an instrument to determine energy of incoming particles by measuring energy loss of the shower particles.


CALET is a three layer structure. The TASC, which lies at the bottom, adopts "lead tungstate (PbWO4) crystals" for a scintillator. It is the thickest scintillator as a cosmic ray observation instrument, and has the incomparable capability of precisely determining energy and identifying particle at high energies over 1 TeV. The cross section of the scintillating fibers used in the IMC in the middle layer is 1 square mm so that we can obtain sufficient information by read-out of each fiber data, which is necessary for determining the arrival direction and types of incoming cosmic rays. Therefore, CALET can explore the high-energy region as a whole calorimeter, which had been difficult to observe by a conventional method.

- Tera electron volt (TeV) region observation and dark matter

Conventional research says that dark matter is highly likely the "weakly interacting massive particles (WIMP)" which was generated at the early universe. In theory, the WIMP creates already-known elementary particles (such as electron/positron pairs) through pair annihilation and decay, and the maximum energy of the created particles is limited to the mass energy of the WIMP. The WIMP's mass is expected to be more than several 100 GeV based on the past observation of electron/positron. Therefore, observation of electrons/positrons in the TeV region by CALET calorimeter is crucial for searching dark matter. CALET is the first instrument that can achieve the electron observations in such a high-energy region.

Reference:

- CALET introduction websites:

http://iss.jaxa.jp/en/kiboexp/ef/calet/ (JAXA website)

http://calet.jp/en/ (Waseda University website)

Images, Text, Credits: Japan Aerospace Exploration Agency (JAXA)/National Research and Development Agency/Waseda University.

Greetings, Orbiter.ch

Reentry data will help improve prediction models








ESA - Space Situational Awareness logo.

Reentry data will help improve prediction models

23 October 2015

A rare reentry of a suspected rocket body from a very high orbit next month offers an excellent opportunity to gather data to improve our knowledge of how objects interact with Earth’s atmosphere.

The expected 13 November reentry of what is likely to be a rocket body poses very little risk to anyone but could help scientists improve our understanding of how any object – man-made or natural – interacts with Earth’s atmosphere.

Returning to Earth

Observing and studying the reentry will help improve orbital models and reentry prediction tools, and can be used by scientists studying near-Earth objects (NEOs), such as natural asteroids, or the orbital decay of artificial objects such as satellites.

It was discovered by the Catalina Sky Survey in 2013 and has been observed several times since then by the same team, who have been sharing their data via the US-based Minor Planet Centre (MPC), the International Astronomical Union’s official repository for such observations.

Man-made origins

As confirmed by experts at ESA's NEO Coordination Centre (NEOCC), ESRIN, Italy, the object, dubbed WT1190F, is thought to be a discarded rocket body; it is orbiting Earth every three weeks in a highly ‘eccentric’ – that is, non-circular – orbit.

“NEO experts have used observational data to estimate the object’s density, which turns out to be much less than that of the solid rocky material that comprises many asteroids,” says Detlef Koschny, responsible for NEO activities at ESA’s Space Situational Awareness (SSA) programme office.

Detecting space hazards

“This density is in fact compatible with the object being a hollow shell, such as the spent upper stage of a rocket body or part of a stage.”

Forecast reentry next month

It is now predicted to reenter Earth's atmosphere in a few weeks, around 06:19 GMT (11:49 local; 07:19 CET) on 13 November 2015.

“The object is quite small, at most a couple of metres in diameter, and a significant fraction if not all of it can be expected to completely burn up in the atmosphere,” says Tim Flohrer, from ESA’s Space Debris Office at the ESOC operations centre in Darmstadt, Germany.

Whatever is left is expected to fall into the ocean about 100 km off the southern coast of Sri Lanka. Its mass is not sufficient to cause any risk to the area, but the show will still be spectacular, since for a few seconds the object will become quite bright in the mid-day sky.

Tim says this object is rather special as it is likely man-made, but was discovered by an NEO monitoring system and its orbit has many similarities with an NEO orbit.

This enables ESA experts to predict the impact time and location quite precisely, well in advance, which is usually not possible in comparison with reentering space-debris objects.

The more observations, teh better

During the next few weeks, the NEOCC will implement observational campaigns to collect as much data as possible on this object, explains Marco Micheli, as astronomer working at the NEOCC.

“The first goal will be to better understand the reentry of satellites and debris from highly eccentric orbits,” he says.

“Second, it provides an ideal opportunity to test our readiness for any possible future atmospheric entry events involving an asteroid, since the components of this scenario, from discovery to impact, are all very similar.”

Astronomers who may wish to observe the object are welcome to contact ESA’s NEOCC for further information.

About Space Situational Awareness

The objective of ESA’s SSA programme is to support Europe's independent utilisation of, and access to, space through the provision of timely and accurate information and data regarding the space environment, especially regarding hazards to infrastructure in orbit and on the ground. In general, these hazards stem from possible collisions between objects in orbit, harmful space weather and potential strikes by natural objects, such as asteroids, that cross Earth’s orbit.

More information via http://www.esa.int/ssa

Editor's note: Text updated 23 October to remove map of forecast reentry location, as this is still uncertain, and to correct the citation for Tim Flohrer.

Images, Text, Credits: ESA/B. Bolin, R. Jedicke, M. Micheli/CC BY-SA IGO 3.0.

Best regards, Orbiter.ch

A Hubble View of Starburst Galaxy Messier 94












NASA - Hubble Space Telescope patch.

Oct. 23, 2015


his image shows the galaxy Messier 94, which lies in the small northern constellation of the Hunting Dogs, about 16 million light-years away.

Within the bright ring or starburst ring around Messier 94, new stars are forming at a high rate and many young, bright stars are present within it.

The cause of this peculiarly shaped star-forming region is likely a pressure wave going outwards from the galactic center, compressing the gas and dust in the outer region. The compression of material means the gas starts to collapse into denser clouds. Inside these dense clouds, gravity pulls the gas and dust together until temperature and pressure are high enough for stars to be born.

The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency. NASA's Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy, in Washington.

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

Text credit: European Space Agency/Image credit: ESA/NASA/Ashley Morrow.

Greetings, Orbiter.ch

jeudi 22 octobre 2015

Astronauts Tailor Spacesuits as Crew Explores Human Research












ISS - Expedition 45 Mission patch.

October 22, 2015

The crew started their day checking out Cubesat gear and researching a wide variety of science to benefit humanity on and off Earth. Later, two astronauts tried on their spacesuits to ensure a good fit before next week’s spacewalk.


Image above: A U.S. spacesuit is pictured inside the Quest joint airlock. Image Credit: NASA.

Commander Scott Kelly and Flight Engineer Kjell Lindgren were in the Kibo lab module Thursday morning inspecting and photographing a small satellite deployer mechanism. The mechanism failed to eject a pair of Cubesats two weeks ago and payload controllers are troubleshooting the issue.

During the afternoon, the duo got back together inside the U.S. Quest airlock and tried on the spacesuits they will wear on spacewalks scheduled for Oct. 28 and Nov. 6. They were assisted inside the airlock by Japanese astronaut Kimiya Yui and cosmonaut Sergey Volkov. Yui will guide the spacewalkers and operate the 57.7 foot Canadarm2 robotic arm during the spacewalks.


Image above: Expedition 45 crew members Kimiya Yui, Kjell Lindgren and Sergey Volkov work inside the Quest airlock to get a pair of spacesuits ready for upcoming spacewalks. Image Credit: NASA TV.

The first spacewalk is set to last six-hours and 30-minutes after Kelly and Lindgren set their spacesuits to battery power. The duo will exit Quest to place a thermal cover over a dark matter detection experiment, lubricate the 57.7 foot Canadarm2 robotic and route power cables for a future docking port.

More human research took place today as the crew looked at brain adaptation and cognitive performance on the space station. The crew also explored sleep disturbances and changes in cardiac and respiratory behavior during long-term missions.

International Space Station (ISS). Image Credit: NASA

The entire crew still continued the work of on-orbit science, the primary purpose of the space station. Cosmonaut Mikhail Kornienko, along with Kelly and Lindgren performed cardiac scans with an ultrasound for the Ocular Health study. Japanese astronaut Kimiya Yui set up a mouse habitat inside the Cell Biology Experiment Facility.

Related links:

Brain adaptation: http://www.nasa.gov/mission_pages/station/research/experiments/1007.html

Cognitive performance: http://www.nasa.gov/mission_pages/station/research/experiments/1256.html

Sleep disturbances: http://www.nasa.gov/mission_pages/station/research/experiments/1802.html

Cardiac and respiratory behavior: http://www.energia.ru/en/iss/researches/human/19.html

Ocular Health study: http://www.nasa.gov/mission_pages/station/research/experiments/204.html

Cell Biology Experiment Facility: http://www.nasa.gov/mission_pages/station/research/experiments/342.html

Expedition 45: https://blogs.nasa.gov/spacestation/category/expedition-45/

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

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

Best regards, Orbiter.ch

NASA Takes Lasercom a Step Forward









NASA - Lunar Laser Communication Demonstration (LLCD) logo.

Oct. 22, 2015

A NASA-developed laser communication (lasercom) system made headlines in 2013 when it demonstrated record-breaking data download and upload speeds to the moon. Now, a NASA optical physicist says he can match those speeds — plus provide never-before-achieved, highly precise distance and speed measurements -- all from the same relatively small package.

Called the Space Optical Communication and Navigation System, the breadboard technology is made up of commercially available components simulating both ground and space terminals. It recently demonstrated in laboratory testing that it could provide micrometer-level distance and speed measurements over a 622 megabits-per-second (Mbps) laser communication link.

Advances in Communications, Navigation and Science

“Combined with the large communication bandwidth, high-precision ranging over an optical communication network will bring about significant advances in navigation and communications, to say nothing of science gathering, notably in the area of geodesy,” said technology developer Guan Yang, an optical physicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. (Geodesy is the science of measuring variations in Earth’s gravitational field caused by changing land mass.) And because of its diminutive size, “it also will enable use on CubeSats,” an increasingly popular spacecraft bus that typically is no larger than a shoebox.

The ground-based test was similar to one carried out in late 2013 aboard another Goddard-developed lasercom experiment hosted on NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE).


Image above: Illustration of The Lunar Laser Communication Demonstration (LLCD) is NASA's first high-rate, two-way, space laser communication demonstration. Image Credits: NASA/GSFC.

During the LADEE demonstration, the Lunar Laser Communication Demonstration (LLCD) experiment downloaded and uploaded test data to and from lunar orbit at 622 megabits per second (Mbps) and 20 Mbps, respectively, proving that it could operate as well as any NASA radio system. Mission operators also used LLCD’s lasercom system to download LADEE’s stored science and spacecraft data. It took just four minutes to download the data, a feat that would have taken several days if using only LADEE’s onboard radio system at 50 kilobits per second.

But before the LLCD mission could break the data-transmission records, it needed to know the speed of the LADEE spacecraft as it orbited the moon as well as its distance from the LLCD ground terminals. This required that the high-frequency laser beam that carried the embedded data also obtained very precise distance and speed measurements.

It succeeded. LLCD’s instrument gathered velocity measurements with a precision better than 10 millimeters per second; its position calculations were precise to within 12 millimeters, the best measurements ever recorded over lunar distances.


Image above: Guan Yang (right) and his research associate, Wei Lu, pose in front of the lasercom breadboard they created to demonstrate high data-rate download and uplink speeds as well as highly precise distance and speed measurements all from the same, relatively small package. Image Credits: NASA/W. Hrybyk.

Besting LLCD

Yang’s new miniaturized lasercom transceiver, however, improved upon LLCD’s precision by several orders of magnitude in laboratory testing. In addition to transmitting data at LLCD’s record-breaking rate of 622 Mbps, it measured speed within a precision of less than 10 micrometers per second and distances within 20 micrometers.

The system achieved these unprecedented precise measurements by incorporating a Doppler frequency — which can be likened to an ambulance siren that increases or decreases in pitch as the vehicle travels closer or farther away — enabled by a highly specialized computing algorithm, called the Fast Fourier Transform.

“When you’re trying to predict where something is, one of the issues is eliminating measurement errors,” said Dennis Woodfork, a Goddard assistant chief for technology specializing in navigation and communication technologies. “If errors build too much, you will lose position, and therefore, you won’t know where the spacecraft will be in the future. Guan’s measurements are at least an order-of-magnitude better. He got great ranging.”

Yang agrees. “If you can measure that precisely, you can easily use it for navigation,” he said. He envisions its use on a constellation of smallsats flying in an exacting formation to get simultaneous, multi-point observations or as the navigational guide to carry out autonomous rendezvous and docking.

Science also could benefit, he said. Due to its precise pointing and micrometer-level, two-way ranging, he believes the technology is particularly ideal for geodesy, the science of measuring variations in Earth’s gravitational field. “This system opens a new way for to carry out all types of science missions,” Yang said.

Although pleased with the test results, Yang now wants to further improve the technology and ultimately fly it on a CubeSat. “The test proved the concept and precision in the lab. I’m now talking with the science community to find an application. We are targeting a CubeSat opportunity.”

Related links:

Lasercom experiment: http://www.nasa.gov/press/2013/october/nasa-laser-communication-system-sets-record-with-data-transmissions-to-and-from/#.VfrTQXu07OS

Lunar Laser Communication Demonstration (LLCD): http://esc.gsfc.nasa.gov/267/271.html

For more Goddard technology news, go to https://gsfctechnology.gsfc.nasa.gov/newsletter/Current.pdf

For more information about LADEE, visit: http://www.nasa.gov/ladee

Images (mentioned), Text, Credits: NASA’s Goddard Space Flight Center/Lori Keesey/Lynn Jenner.

Greetings, Orbiter.ch

NASA Completes Critical Design Review for Space Launch System












NASA - Space Launch System (SLS) logo.

Oct. 22, 2015

For the first time in almost 40 years, a NASA human-rated rocket has completed all steps needed to clear a critical design review (CDR). The agency’s Space Launch System (SLS) is the first vehicle designed to meet the challenges of the journey to Mars and the first exploration class rocket since the Saturn V.

SLS will be the most powerful rocket ever built and, with the agency’s Orion spacecraft, will launch America into a new era of exploration to destinations beyond Earth’s orbit. The CDR provided a final look at the design and development of the integrated launch vehicle before full-scale fabrication begins.


Image above: Artist concept of the Block I configuration of NASA’s Space Launch System (SLS). The SLS Program has completed its critical design review, and the program has concluded that the core stage of the rocket will remain orange along with the Launch Vehicle Stage Adapter, which is the natural color of the insulation that will cover those elements. Image Credits: NASA.

“We’ve nailed down the design of SLS, we’ve successfully completed the first round of testing of the rocket’s engines and boosters, and all the major components for the first flight are now in production,” said Bill Hill, deputy associate administrator of NASA’s Exploration Systems Development Division. “There have been challenges, and there will be more ahead, but this review gives us confidence that we are on the right track for the first flight of SLS and using it to extend permanent human presence into deep space.”

The CDR examined the first of three configurations planned for the rocket, referred to as SLS Block 1. The Block I configuration will have a minimum 70-metric-ton (77-ton) lift capability and be powered by twin boosters and four RS-25 engines. The next planned upgrade of SLS, Block 1B, would use a more powerful exploration upper stage for more ambitious missions with a 105-metric-ton (115-ton) lift capacity. Block 2 will add a pair of advanced solid or liquid propellant boosters to provide a 130-metric-ton (143-ton) lift capacity. In each configuration, SLS will continue to use the same core stage and four RS-25 engines.

The SLS Program completed the review in July, in conjunction with a separate review by the Standing Review Board, which is composed of seasoned experts from NASA and industry who are independent of the program. Throughout the course of 11 weeks, 13 teams – made up of senior engineers and aerospace experts across the agency and industry – reviewed more than 1,000 SLS documents and more than 150 GB of data as part of the comprehensive assessment process at NASA’s Marshall Space Flight Center in Huntsville, Alabama, where SLS is managed for the agency.

The Standing Review Board reviewed and assessed the program’s readiness and confirmed the technical effort is on track to complete system development and meet performance requirements on budget and on schedule.

The program briefed the results of the review in October to the Agency Program Management Council, led by NASA Associate Administrator Robert Lightfoot, as the final step in the CDR process.

This review is the last of four reviews that examine concepts and designs. The next step for the program is design certification, which will take place in 2017 after manufacturing, integration and testing is complete. The design certification will compare the actual final product to the rocket’s design. The final review, the flight readiness review, will take place just prior to the 2018 flight readiness date.

SLS block 1 expanded view. Image Credits: NASA/MSFC

“This is a major step in the design and readiness of SLS,” said John Honeycutt, SLS program manager. “Our team has worked extremely hard, and we are moving forward with building this rocket. We are qualifying hardware, building structural test articles, and making real progress.”

Critical design reviews for the individual SLS elements of the core stage, boosters and engines were completed successfully as part of this milestone. Also as part of the CDR, the program concluded the core stage of the rocket and Launch Vehicle Stage Adapter will remain orange, the natural color of the insulation that will cover those elements, instead of painted white. The core stage, towering more than 200 feet tall and with a diameter of 27.6 feet, will carry cryogenic liquid hydrogen and liquid oxygen fuel for the rocket’s four RS-25 engines.

The integrated spacecraft and payloads are nearing completion on their CDR. Flight hardware currently is in production for every element. NASA is preparing for a second qualification test for the SLS boosters, and structural test articles for the core and upper stages of the rocket are either completed or currently in production. NASA also recently completed the first developmental test series on the RS-25 engines.

Related links:

ESD (Exploration Systems Development): http://www.nasa.gov/exploration/systems/index.html

Journey to Mars: http://www.nasa.gov/topics/journeytomars/index.html

Future program reviews will focus on SLS integration and flight readiness. For more information on SLS, visit: http://www.nasa.gov/sls

Images (mentioned), Text, Credits: NASA/Kathryn Hambleton/Marshall Space Flight Center/Shannon Ridinger/Karen Northon.

Best regards, Orbiter.ch

Last of Pluto’s Moons – Mysterious Kerberos – Revealed by New Horizons












NASA New Horizons Mission logo.

Oct. 22, 2015


Image above: Kerberos Revealed. This image of Kerberos was created by combining four individual Long Range Reconnaissance Imager (LORRI) pictures taken on July 14, approximately seven hours before New Horizons’ closest approach to Pluto, at a range of 245,600 miles (396,100 km) from Kerberos. The image was deconvolved to recover the highest possible spatial resolution and oversampled by a factor of eight to reduce pixilation effects. Kerberos appears to have a double-lobed shape, approximately 7.4 miles (12 kilometers) across in its long dimension and 2.8 miles (4.5 kilometers) in its shortest dimension. Image Credits: NASA/JHUAPL/SwRI.

Images of Pluto’s tiny moon Kerberos taken by NASA’s New Horizons spacecraft –and just sent back to Earth this week – complete the family portrait of Pluto’s moons.

Kerberos appears to be smaller than scientists expected and has a highly-reflective surface, counter to predictions prior to the Pluto flyby in July. “Once again, the Pluto system has surprised us,” said New Horizons Project Scientist Hal Weaver, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland.

The new data, downlinked from the New Horizons spacecraft on Oct. 20, show that Kerberos appears to have a double-lobed shape, with the larger lobe approximately 5 miles (8 kilometers) across and the smaller lobe approximately 3 miles (5 kilometers) across. Science team members speculate from its unusual shape that Kerberos could have been formed by the merger of two smaller objects. The reflectivity of Kerberos’ surface is similar to that of Pluto’s other small moons (approximately 50 percent) and strongly suggests Kerberos, like the others, is coated with relatively clean water ice.


Image above: Family Portrait of Pluto’s Moons: This composite image shows a sliver of Pluto’s large moon, Charon, and all four of Pluto’s small moons, as resolved by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft. All the moons are displayed with a common intensity stretch and spatial scale (see scale bar). Charon is by far the largest of Pluto’s moons, with a diameter of 751 miles (1,212 kilometers). Nix and Hydra have comparable sizes, approximately 25 miles (40 kilometers) across in their longest dimension above. Kerberos and Styx are much smaller and have comparable sizes, roughly 6-7 miles (10-12 kilometers) across in their longest dimension. All four small moons have highly elongated shapes, a characteristic thought to be typical of small bodies in the Kuiper Belt. Image Credits: NASA/JHUAPL/SwRI.

Before the New Horizons encounter with Pluto, researchers had used Hubble Space Telescope images to “weigh” Kerberos by measuring its gravitational influence on its neighboring moons.  That influence was surprisingly strong, considering how faint Kerberos was. They theorized that Kerberos was relatively large and massive, appearing faint only because its surface was covered in dark material. But the small, bright-surfaced Kerberos--now revealed in these new images--shows that the idea was incorrect, for reasons that are not yet understood.

“Our predictions were nearly spot-on for the other small moons, but not for Kerberos,” said New Horizons co-investigator Mark Showalter, of the SETI Institute in Mountain View, California. The new results are expected to lead to a better understanding of Pluto’s fascinating satellite system.

New Horizons is part of NASA’s New Frontiers Program, managed by the agency’s Marshall Space Flight Center in Huntsville, Alabama.  APL designed, built, and operates the New Horizons spacecraft and manages the mission for NASA’s Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning.

For more information about New Horizons mission, visit: http://www.nasa.gov/mission_pages/newhorizons/main/index.html

Images (mentioned), Text, Credits. NASA/Tricia Talbert.

Greetings, Orbiter.ch

Hubble Spies Big Bang Frontiers












ESA - Hubble Space Telescope logo.

Oct. 22, 2015

Hubble Frontier Fields view of MACSJ0416.1–2403

Observations by the NASA/ESA Hubble Space Telescope have taken advantage of gravitational lensing to reveal the largest sample of the faintest and earliest known galaxies in the Universe. Some of these galaxies formed just 600 million years after the Big Bang and are fainter than any other galaxy yet uncovered by Hubble. The team has determined, for the first time with some confidence, that these small galaxies were vital to creating the Universe that we see today.

An international team of astronomers, led by Hakim Atek of the Ecole Polytechnique Fédérale de Lausanne, Switzerland, has discovered over 250 tiny galaxies that existed only 600-900 million years after the Big Bang [1] — one of the largest samples of dwarf galaxies yet to be discovered at these epochs. The light from these galaxies took over 12 billion years to reach the telescope, allowing the astronomers to look back in time when the universe was still very young.

Hubble Frontier Fields view of MACSJ0717.5+3745

Although impressive, the number of galaxies found at this early epoch is not the team’s only remarkable breakthrough, as Johan Richard from the Observatoire de Lyon, France, points out, “The faintest galaxies detected in these Hubble observations are fainter than any other yet uncovered in the deepest Hubble observations.”

By looking at the light coming from the galaxies the team discovered that the accumulated light emitted by these galaxies could have played a major role in one of the most mysterious periods of the Universe’s early history — the epoch of reionisation. Reionisation started when the thick fog of hydrogen gas that cloaked the early Universe began to clear. Ultraviolet light was now able to travel over larger distances without being blocked and the Universe became transparent to ultraviolet light [2].

Hubble Frontier Fields view of Abell 2744

By observing the ultraviolet light from the galaxies found in this study the astronomers were able to calculate whether these were in fact some of the galaxies involved in the process. The team determined, for the first time with some confidence, that the smallest and most abundant of the galaxies in the study could be the major actors in keeping the Universe transparent. By doing so, they have established that the epoch of reionisation — which ends at the point when the Universe is fully transparent — came to a close about 700 million years after the Big Bang [3].

Lead author Atek explained, “If we took into account only the contributions from bright and massive galaxies, we found that these were insufficient to reionise the Universe. We also needed to add in the contribution of a more abundant population of faint dwarf galaxies.”

To make these discoveries, the team utilised the deepest images of gravitational lensing made so far in three galaxy clusters, which were taken as part of the Hubble Frontier Fields programme [4]. These clusters generate immense gravitational fields capable of magnifying the light from the faint galaxies that lie far behind the clusters themselves. This makes it possible to search for, and study, the first generation of galaxies in the Universe.

video
Hubble and the sunrise over Earth

Jean-Paul Kneib, co-author of the study from the Ecole Polytechnique Fédérale de Lausanne, Switzerland, explains, “Clusters in the Frontier Fields act as powerful natural telescopes and unveil these faint dwarf galaxies that would otherwise be invisible.”

Co-author of the study Mathilde Jauzac, from Durham University, UK, and the University of KwaZulu-Natal, South Africa, remarks on the significance of the discovery and Hubble’s role in it,“Hubble remains unrivalled in its ability to observe the most distant galaxies. The sheer depth of the Hubble Frontier Field data guarantees a very precise understanding of the cluster magnification effect, allowing us to make discoveries like these.”

These results highlight the impressive possibilities of the Frontier Fields programme with more galaxies, at even earlier time, likely to be revealed when Hubble peers at three more of these galaxy clusters in the near future.

Notes:

[1] The calculated redshift for these objects is between z = 6 and z = 8.

[2] Neutral hydrogen gas absorbs all the high-energy ultraviolet light emitted by hot young stars very efficiently. At the same time, the absorbed ultraviolet light ionises the hydrogen. The very low density ionised hydrogen gas filling the universe became fully transparent.The hot stars carve out transparent bubbles in the gas and once all these bubbles merge to fill all of space, reionisation is said to be complete and the Universe becomes transparent to ultraviolet light.

[3] This corresponds to a redshift of about z = 7.5.

[4] The Hubble Frontier Fields is a three-year, 840-orbit programme which will yield the deepest views of the Universe to date, combining the power of Hubble with the gravitational amplification of light around six different galaxy clusters to explore more distant regions of space than could otherwise be seen.

Notes for editors:

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

More information:

This research was presented in a paper entitled “Are Ultra-faint Galaxies at z = 6−8 Responsible for Cosmic Reionization? Combined Constraints from the Hubble Frontier Fields Clusters And Parallels”, by H. Atek et al., to appear in the Astrophysical Journal.

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

The international team of astronomers in this study consists of Hakim Atek (Laboratoire d’Astrophysique, Ecole Polytechnique Fédérale de Lausanne, Switzerland ; Department of Astronomy, Yale University, USA), Johan Richard (CRAL, Observatoire de Lyon, France), Mathilde Jauzac (Institute for Computational Cosmology, Durham University, UK; Astrophysics and Cosmology Research Unit, University of KwaZulu-Natal, South Africa), Jean-Paul Kneib (Laboratoire d’Astrophysique, Ecole Polytechnique Fédérale de Lausanne, Switzerland; Aix Marseille Université, CNRS, LAM UMR 7326, France), Priyamvada Natarajan (Department of Astronomy, Yale University, USA), Marceau Limousin (Aix Marseille Université, CNRS, LAM UMR 7326, France), Daniel Schaerer (Observatoire de Genève, Switzerland; CNRS, IRAP, France), Eric Jullo (Aix Marseille Université, CNRS, LAM UMR 7326, France), Harald Ebeling (Institute for Astronomy, University of Hawaii, USA), Eiichi Egami (Steward Observatory, University of Arizona, USA), and Benjamin Clement (CRAL, Observatoire de Lyon, France).

Links:

Images of Hubble: http://www.spacetelescope.org/images/archive/category/spacecraft/

Frontier Fields programme: http://frontierfields.org/

Link to science paper: http://www.spacetelescope.org/static/archives/releases/science_papers/heic1523a.pdf

Hubblecast 70: Peering around cosmic corners: http://www.spacetelescope.org/videos/hubblecast70a/

Images, Text, Video, Credits: NASA, ESA and the HST Frontier Fields team (STScI).

Greetings, Orbiter.ch