samedi 22 septembre 2018

Japanese Rocket Blasts Off to Resupply Station

JAXA - HB-II Transfer Vehicle (HTV-7) Mission patch.

September 22, 2018

Image above: Japan’s H-IIB rocket with the HTV-7 resupply ship on top blasts off at 1:52 p.m. EDT on Friday, Sept. 22 (2:52 a.m. Sept. 23 Japan standard time) from the Tanegashima Space Center. Image Credits: JAXA/NASA.

The Japan Aerospace Exploration Agency (JAXA)’s H-IIB rocket launched at 1:52 p.m. EDT on Friday, Sept. 22 (2:52 a.m. Sept. 23 Japan standard time) from the Tanegashima Space Center in southern Japan. At the time of launch, the space station was 254 miles over the southwest Pacific, west of Chile.

HTV-7 launched by H-IIB F7

A little more than 15 minutes after launch, the unpiloted H-II Transfer Vehicle-7 (HTV-7) cargo spacecraft successfully separated from the rocket and began its four-and-a-half rendezvous with the International Space Station.

On Thursday, Sept. 27, the HTV-7 will approach the station from below and slowly inch its way toward the orbiting laboratory. Expedition 56 Commander Drew Feustel and Flight Engineer Serena Auñón-Chancellor of NASA will operate the station’s Canadarm2 robotic arm to capture the spacecraft as it approaches. Flight Engineer Alexander Gerst of ESA (European Space Agency) will monitor HTV-7 systems during its approach. Robotic ground controllers will then install it on the Earth-facing side of the Harmony module, where it will remain for several weeks.

Image above: The Japanese HTV-6 cargo vehicle is seen during final approach to the International Space Station before it is captured by the remote Canadarm 2. HTV-6 launched from the Tanegashima Space Center in southern Japan on Friday, Dec. 9, and arrived at the station on Tuesday, Dec. 13. The vehicle was loaded with more than 4.5 tons of supplies, water, spare parts and experiment hardware. Image Credit: NASA.

NASA TV coverage of the Sept. 27 rendezvous and grapple will begin at 6:30 a.m. ET. Capture is scheduled for approximately 8:00 a.m. After a break, NASA TV coverage will resume at 10:30 a.m. for spacecraft installation to the space station’s Harmony module.

In addition to new hardware to upgrade the station’s electrical power system, the HTV-7 is carrying a new sample holder for the Electrostatic Levitation Furnace (JAXA-ELF), a protein crystal growth experiment at low temperatures (JAXA LT PCG), an investigation that looks at the effect of microgravity on bone marrow (MARROW), a Life Sciences Glovebox, and additional EXPRESS Racks.

Related links:

JAXA Press Release:

H-II Transfer Vehicle-7 (HTV-7):

Electrostatic Levitation Furnace (JAXA-ELF):



Life Sciences Glovebox:



Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Video, Text, Credits: NASA/Mark Garcia/JAXA/NASA TV/SciNews.

Best regards,

vendredi 21 septembre 2018

Space Station Science Highlights: Week of September 17, 2018

ISS - Expedition 56 Mission patch.

Sept. 21, 2018

The Expedition 56 crew members aboard the International Space Station conducted a variety of biomedical and physical science research this week as they continued to await the arrival of Japan Aerospace Exploration Agency’s (JAXA) HTV-7 resupply vehicle.

Image above: A view of the European Space Agency Columbus Lab Module, looking across into the Japanese Experiment Module. Image Credit: NASA.

As a result of inclement weather, JAXA has postponed the launch of a cargo spacecraft from the Tanegashima Space Center in southern Japan to Saturday, Sept. 22. Live coverage of the launch will begin at 1:30 p.m. on NASA Television and the agency’s website.

Learn more about the science happening on station below:

Crew prepares for ACME operations

The Advanced Combustion Microgravity Experiment (ACME) investigation is a set of five independent studies of gaseous flames to be conducted in the Combustion Integration Rack (CIR), one of which being Electric-Field Effects on Laminar Diffusion Flames (E-FIELD Flames).

In E-FIELD Flames, an electric field with voltages as high as 10,000 volts is established between the burner and a mesh electrode. The motion of the charged ions, which are naturally produced within the flame, are strongly affected by a high-voltage electric field. The resulting ion-driven wind can dramatically influence the stability and sooting behavior of the flame. Measurements are made of electric-field strength, the ion current passing through the flame, and flame characteristics such as the size, structure, temperature, soot, and stability. Conducting the tests in microgravity allows for simplifications in the analysis, enabling new understanding and the potential development of less polluting and more efficient combustion technology for use on Earth.

Animation above: Oleg Artemyev of Roscosmos works within the Combustion Integration Rack (CIR) as a part of the ACME investigation.
The crew conducted maintenance on the rack in order to prepare for E-FIELD Flames to begin. Animation Credit: NASA.

This week, in preparation for E-FIELD Flames operations, crew members replaced several components including power supply, burner, igniter tip and controller, as well as installing the mesh.

Crew replaces materials for experiment run

The Atomization experiment uses a high-speed camera to observe the disintegration processes of low-speed water jets under various conditions. These observations validate a new atomization concept, developed from drop tower experiments on Earth, to correctly predict the breakup positions of a liquid stream. This information is key to improving spray combustion processes inside rocket and jet engines.

Animation above: NASA astronaut Serena Auñón-Chancellor works to replace sample syringes and a water trip in preparation for an Atomization experiment run. Animation Credit: NASA.

This week, the crew replaced sample syringes and a water trap, allowing the ground team to initiate and complete an experiment run.

Samples collected, DNA sequenced as a part of BEST investigation

Biomolecule Extraction and Sequencing Technology (BEST) seeks to advance use of sequencing in space in three ways: identifying microbes aboard the space station that current methods cannot detect, assessing microbial mutations in the genome because of spaceflight and performing direct RNA sequencing.

Image above: View during Biomolecule Extraction and Sequencing Technology (BEST) Experiment 1 Part 1. The objective is to identify bacteria directly from ISS surfaces through the swabbing and extraction of DNA from the swab using mini PCR. The DNA will undergo further sample preparation and sequencing with the Biomolecule Sequencer. Image Credit: NASA.

This week, crew members performed operations to initiate DNA sequences from samples collected on Monday of this week. 

Learn more about the BEST investigation here:

Crew conducts maintenance on camera used in sediment investigation

Binary Colloidal Alloy Test - Cohesive Sediment (BCAT-CS) studies dynamic forces between sediment particles that cluster together. For the study, scientists sent mixtures of quartz and clay particles to the space station and subjected them to various levels of simulated gravity. Conducting the experiment in microgravity makes it possible to separate out different forces that act on sediments and look at the function of each.

View from inside ISS Cupola. Image Credit: NASA

Understanding how sediments behave has a range of applications on Earth, including predicting and mitigating erosion, improving water treatment, modeling the carbon cycle,  sequestering contaminants and more accurately finding deep sea oil reservoirs.

Space to Ground: Long Distance Call: 09/21/2018

Video credits: NASA Johnson.

This week, the crew conducted maintenance such as adjusting the camera’s alignment, changing the battery on the camera’s flash, and refocusing the camera itself.

Other work was done on these investigations: Microbial Tracking-2, Plant Habitat-1, Plant Habitat, ISS HAM, SpaceTex-2, DOSIS-3D, Metabolic Space, Biochemical Profile, Cell Free Epigenome/Medical Proteomics, Veggie, HRF-2, MUSES, ZeroG Battery Testing, JAXA ELF, and Team Task Switching.

Related links:

Expedition 56:

NASA Television:

Advanced Combustion Microgravity Experiment (ACME):

Combustion Integration Rack (CIR):

E-FIELD Flames:


Biomolecule Extraction and Sequencing Technology (BEST):

Binary Colloidal Alloy Test - Cohesive Sediment (BCAT-CS):

Microbial Tracking-2:

Plant Habitat-1:

Plant Habitat:




Metabolic Space:

Biochemical Profile:

Cell Free Epigenome:

Medical Proteomics:




ZeroG Battery Testing:


Team Task Switching:

Spot the Station:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Animations (mentioned), Video (mentioned), Text, Credits: NASA/Michael Johnson/Yuri Guinart-Ramirez, Lead Increment Scientist Expeditions 55 & 56.

Best regards,

NASA’s MAVEN Selfie Marks Four Years in Orbit at Mars

NASA - MAVEN Mission logo.

Sept. 21, 2018

Today, NASA’s MAVEN spacecraft celebrates four years in orbit studying the upper atmosphere of the Red Planet and how it interacts with the Sun and the solar wind. To mark the occasion, the team has released a selfie image of the spacecraft at Mars.

“MAVEN has been a tremendous success,” said Bruce Jakosky, MAVEN principal investigator from the University of Colorado, Boulder. “The spacecraft and instruments continue to operate as planned, and we’re looking forward to further exploration of the Martian upper atmosphere and its influence on climate.”

Image above: This image is a composite selfie taken by MAVEN's Imaging Ultraviolet Spectrograph (IUVS) instrument that normally looks at ultraviolet emissions from the Martian upper atmosphere. Lines are sketched in to show approximately where components of the spacecraft are that were not able to be imaged due to the limited motion of the instrument around its support boom. Thrusters can be seen at the lower left and right, the Electra communications antenna at the bottom toward the left, the magnetometer and sun sensor at the end of the solar-panels at the upper left, the tip of the communications antenna at the top middle. In addition, the shadow of the IUVS and of its support boom can be seen down the middle of the spacecraft body. Image Credits: University of Colorado/NASA.

MAVEN has obtained a selfie image, looking at ultraviolet wavelengths of sunlight reflected off of components of the spacecraft. The image was obtained with the Imaging Ultraviolet Spectrograph (IUVS) instrument that normally looks at ultraviolet emissions from the Martian upper atmosphere. The IUVS instrument is mounted on a platform at the end of a 1.2-m boom (its own “selfie stick”), and by rotating around the boom can look back at the spacecraft. The selfie was made from 21 different images, obtained with the IUVS in different orientations, that have been stitched together.

The mission launched on Nov. 18, 2013, and went into orbit around Mars on Sept. 21, 2014. During its time at Mars, MAVEN has answered many questions about the Red Planet.

Image above: This image identifies the various parts of the MAVEN spacecraft selfie, with an artist's sketch of the spacecraft for comparison. Individual components are identified in both the selfie and the computer image. Notice that the computer-generated image shows the IUVS instrument, but that it is not visible in the actual selfie (because that’s what’s taking the picture!). Image Credits: University of Colorado/NASA.

The spacecraft has made the following discoveries and science results, among others:

- Acquired compelling evidence that the loss of atmosphere to space has been a major driver of climate change on Mars.

- Determined that the stripping of ions from the upper atmosphere to space during a solar storm can be enhanced by a factor of 10 or more, possibly making these storms a major driver of loss of the atmosphere through time.

- Discovered two new types of Martian auroras – diffuse aurora and proton aurora. Neither type has a direct connection to the local or global magnetic field or to magnetic cusps, as auroras do on Earth.

- MAVEN has made direct observations of a metal-ion layer in the Martian ionosphere, the first direct detection on any planet other than the Earth. The ions are produced by a steady influx of incoming interplanetary dust.

- Demonstrated that the majority of the CO2 on the planet has been lost to space and that there isn’t enough left to terraform the planet by warming it, even if the CO2 could be released and put back into the atmosphere.

Next year, engineers will initiate an aerobraking maneuver by skimming the spacecraft through Mars’ upper atmosphere to slow it. This will reduce the highest altitude in MAVEN’s orbit to enhance its ability to serve as a communications relay for data from rovers on the surface. Currently, MAVEN carries out about one relay pass per week with one of the rovers. This number will increase after NASA’s InSight mission lands on Mars in November.

Image above: This image shows part of the MAVEN spacecraft and the limb of Mars in the background. This is one of the individual images that make up the selfie, showing the magnetometer and sun sensor at the end of the solar panel. Mars is seen in the background; the dark spot at the top of the image is the Olympus Mons volcano. Image Credits: University of Colorado/NASA.

MAVEN completed its primary mission in November 2015 and has been operating in an extended mission since that time, continuing its productive investigation of Mars’ upper atmosphere and exploring additional opportunities for science that the new relay orbit will bring.

MAVEN’s principal investigator is based at the University of Colorado’s Laboratory for Atmospheric and Space Physics, Boulder. The university provided two science instruments and leads science operations, as well as education and public outreach, for the mission. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the MAVEN project and provided two science instruments for the mission. Lockheed Martin built the spacecraft and is responsible for mission operations. The University of California at Berkeley’s Space Sciences Laboratory also provided four science instruments for the mission. NASA’s Jet Propulsion Laboratory in Pasadena, California, provides navigation and Deep Space Network support, as well as the Electra telecommunications relay hardware and operations.

For more information on the MAVEN mission, visit:

Images (mentioned), NASA/Karl Hille/GSFC/Nancy Jones.


A satellite captures space junk for the first time

Space Debris illustration.

September 21, 2018

Image above: In this September 2018 image made from video provided by the University of Surrey, a net is launched from a satellite to catch a test object. The experiment was conducted to research ways to clean up debris in orbit around Earth. Image Credit: University of Surrey.

An experimental cleanup device called RemoveDebris has successfully cast a net around a dummy satellite, simulating a technique that could one day capture spaceborne garbage.

The test, which was carried out this week, is widely believed to be the first successful demonstration of space cleanup technology, experts told CNN. And it signals an early step toward solving what is already a critical issue: debris in space.

Millions of pieces of junk are whirling around in orbit, the result of 50 years of space travel and few regulations to keep space clean. At orbital speeds, even a small fleck of paint colliding with a satellite can cause critical damage.

Various companies have plans to send thousands of new satellites into low-Earth orbit, already the most crowded area.

The RemoveDebris experiment is run by a consortium of companies and researchers led by the UK's Surrey Space Centre and includes Airbus, Airbus-owned Surrey Satellite Technology Ltd. and France's Ariane Group.

Researchers captured the test capture on video, which was shared online Wednesday

Guglielmo Aglietti, the director of Surrey Space Centre, said that an operational version of the RemoveDebris technology would cast out a net that remains tethered to the main satellite so the debris can be dragged out of orbit. It could target large pieces of junk, including dead satellites up to 10 meters long.

For the test, however, the dummy satellite and net were left to orbit freely. So it essentially created another piece of uncontrolled debris. But Aglietti said it won't pose a risk for long. The experiment was conducted in a very low orbit, so the dummy satellite should fall out of the sky within a few months and plummet to its grave.

The RemoveDebris satellite will conduct a few more experiments in the coming months, including testing navigation features that could help guide the satellite to a specific piece of debris. It will also test out a harpoon technology that could capture hulking satellites with a spear attached to a string.

Jonathan McDowell, an astrophysicist at the Harvard-Smithsonian Center for Astrophysics, said the success of this week's experiment was exciting, but he cautioned against "over-hyping" it.

"There are dozens of good ideas about how to address this problem, but the devil is always in the details," he said.

A company called AGI helps track and map orbital debris

There are still enormous barriers to clear before operational cleanup missions will be underway, he said, and the most daunting is figuring out how to fund such projects.

The RemoveDebris experiment cost roughly 15 million euros, or $18 million, and it was jointly funded by the European Commission and the groups involved in the project. That's relatively cheap as far as space travel goes. But McDowell pointed out that it will take more than one satellite to make a significant impact.

"You can't just have like one garbage truck going around and picking up each [piece of debris]. To change from one orbit to another requires just as much rocket fuel as getting up there in the first place, so it's tricky to find a solution that is cost effective," McDowell said.

RemoveDebris Net Experiment Raw Footage

Aglietti, the Surrey professor who helped lead the RemoveDebris project, said "the challenge will be to convince the relevant authorities to sponsor these mission."

Aglietti said he hopes RemoveDebris will conduct a few cleanup missions per year, targeting the largest pieces of junk in the most crowded orbits.

But there's geopolitical issues to grapple with as well. International agreements prevent a project carried out by one nation to touch objects that were put into orbit by another country. For example, a UK-led cleanup project couldn't go after a defunct Russian-built rocket booster.

"Currently space debris is a global problem as it affects all nations. Each piece of junk in space is owned by the original operators and orbital debris is not addressed explicitly in current international law," Xander Hall, a mission systems engineer at Airbus, said in an email. "[A]n international effort must be made to claim ownership of the debris and help fund its safe removal." Aglietti is hopeful.

"I think all the stakeholders should get around the table, because it's in everybody's interest to remove that debris," he said.

Related links:

Application form:

ESA’s Space Debris Office:

ESA’s Education Office:

Surrey Space Centre (University of Surrey):

Swiss Space Center (EPFL):

Image, Animations, Video, Text, Credits: ESA/EPFL/University of Surrey/CNN/Jackie Wattles.


Hubble’s Galaxies With Knots, Bursts

NASA - Hubble Space Telescope patch.

Sept. 21, 2018

In the northern constellation of Coma Berenices (Berenice's Hair) lies the impressive Coma Cluster —  a structure of over a thousand galaxies bound together by gravity. Many of these galaxies are elliptical types, as is the brighter of the two galaxies dominating this image: NGC 4860 (center). However, the outskirts of the cluster also host younger spiral galaxies that proudly display their swirling arms. Again, this image shows a wonderful example of such a galaxy in the shape of the beautiful NGC 4858, which can be seen to the left of its bright neighbor and which stands out on account of its unusual, tangled, fiery appearance.

NGC 4858 is special. Rather than being a simple spiral, it is something called a “galaxy aggregate,” which is as the name suggests a central galaxy surrounded by a handful of luminous knots of material that seem to stem from it, extending and tearing away and adding to or altering its overall structure. It is also experiencing an extremely high rate of star formation, possibly triggered by an earlier interaction with another galaxy. As we see it, NGC 4858 is forming stars so frantically that it will use up all of its gas long before it reaches the end of its life. The color of its bright knots indicates that they are formed of hydrogen, which glows in various shades of bright red as it is energized by the many young, hot stars lurking within.

Hubble Space Telescope (HST)

This scene was captured by the NASA/ESA Hubble Space Telescope’s Wide Field Camera 3 (WFC3), a powerful camera designed to explore the evolution of stars and galaxies in the early universe.

For more information about Hubble, visit:

Image, Animation, Credit: ESA/Hubble & NASA/Text: European Space Agency (ESA)/NASA/Karl Hille.


jeudi 20 septembre 2018

Launch Slips One Day as Station Boosts Orbit and Life Science Continues

ISS - Expedition 56 Mission patch.

September 20, 2018

The launch of a Japanese resupply ship to the International Space Station was postponed till Saturday. Meanwhile, the Expedition 56 crew moved on with critical space research and orbital lab maintenance.

Inclement weather at the Tanegashima Space Center in Japan led managers at JAXA (Japan Aerospace Exploration Agency) to postpone the launch of its HTV-7 resupply ship by one day. The HTV-7 is now due to launch atop the H-IIB rocket Saturday at 1:52 p.m. EDT loaded with over five tons of cargo, including new science experiments and science hardware. Its arrival at the station is now planned for Thursday at 7:54 a.m.

Image above: Japan’s HTV-3 resupply ship launches aboard an H-IIB rocket from the Tanegashima Space Center in southern Japan on July 20, 2012, during Expedition 32. Image Credit: JAXA.

The station’s Zvezda service module fired its engines today slightly boosting the space lab’s orbit. The reboost enables a crew swap taking place next month when Expedition 57 begins. Three Expedition 56 crew members will depart on Oct. 4 and return to Earth inside the Soyuz MS-08 spacecraft. A new pair of Expedition 57 crew members will arrive aboard the Soyuz MS-10 crew ship to replace them Oct. 11

Astronauts Ricky Arnold and Serena Auñón-Chancellor conducted a variety of biomedical research today sponsored by scientists from around the world. The duo partnered up for ultrasound scans inside Europe’s Columbus lab module as doctors on the ground monitored in real-time. Arnold also worked throughout the day processing blood and urine samples inside the Human Research Facility’s centrifuge.

International Space Station (ISS). Image Credit: NASA

The biological sample work is supporting a pair of ongoing experiments observing the physiological changes to humans in space. The Repository study analyzes blood and urine samples collected from astronauts before, during and after a space mission. The Biochemical Profile study also researches these samples for markers of astronaut health.

Commander Drew Feustel and Fight Engineer Alexander Gerst worked throughout the orbital lab on housekeeping tasks. Fuestel was in the Unity module installing computer network gear on an EXPRESS rack that can support multiple science experiments. Gerst relocated smoke detectors in the Tranquility module then moved on to computer maintenance in the Destiny lab module.

Small Satellite Demonstrates Possible Solution for 'Space Junk'. Image Credit: NASA

The International Space Station serves as humanity's orbital research platform, conducting a variety of experiments and research projects while in orbit around the planet.

On June 20, 2018, the space station deployed the NanoRacks-Remove Debris satellite into space from outside the Japanese Kibo laboratory module. This technology demonstration was designed to explore using a 3D camera to map the location and speed of orbital debris or "space junk."

The NanoRacks-Remove Debris satellite successfully deployed a net to capture a nanosatellite that simulates debris. Collisions in space could have have serious consequences to the space station and satellites, but research has shown that removing the largest debris significantly reduces the chance of collisions.

Related links:

Expedition 56:

Expedition 57:

Science hardware:

Human Research Facility:


Biochemical Profile:


NanoRacks-Remove Debris:

Small Satellite Missions:



Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

NASA-funded ELFIN To Study How Electrons Get Lost

NASA logo.

September 20, 2018

Three hundred and ten miles above our planet’s surface, near-Earth space is abuzz with action. Here begin the Van Allen Belts, a pair of concentric rings of fast-moving particles and intense radiation that extends more than 30,000 miles farther into space. For the most part these particles are confined to this special region, spiraling along Earth’s magnetic field lines. But sometimes they come too close and crash into our atmosphere — creating the eye-catching diffuse red aurora, but also potentially interfering with critical communications and GPS satellites that we depend on every day.

Image above: An artist’s depiction of the Van Allen Belts, showing Earth’s magnetic field lines and the trajectories of charged particles trapped by them. The twin ELFIN spacecraft are shown following their inclined polar orbit, traced in yellow. Image Credits: UCLA EPSS/NASA SVS.

A new CubeSat mission called The Electron Losses and Fields Investigation, or ELFIN, will study one of the processes that allows energetic electrons to escape the Van Allen Belts and fall into Earth. ELFIN was launched from the Vandenburg Air Force Base in California on Sept. 15, 2018.

When magnetic storms form in near-Earth space, they create waves that jiggle Earth’s magnetic field lines, kicking electrons out of the Van Allen Belts and down into our atmosphere. ELFIN aims to be the first to simultaneously observe this electron precipitation while also verifying the causal mechanism, measuring the magnetic waves and the resulting “lost” electrons.

UCLA sends student-built satellite into space

Video above: During the last five years nearly 250 students have spent thousands of hours designing and building ELFIN, more formally the Electron Losses and Fields Investigation CubeSat. Video Credits: UCLA.

Funded by NASA, The National Science Foundation, and industry partners, ELFIN is a CubeSat mission. CubeSats are small and lightweight satellites, measured in standardized 10-by-10-by-10 cubic centimeter units, that are comparatively quick to develop and come with a price tag at a fraction of larger satellite missions. ELFIN uses two identical 3U, or 3 cubic unit, CubeSats — both about the size of a loaf of bread. By using two satellites instead of one, ELFIN will be able to measure how the precipitated electrons vary across space and time. Designed, built and tested by a team of 250 UCLA students over five years, ELFIN will be the first satellite developed, managed and operated entirely by UCLA. A key advantage of CubeSats is that they allow an inexpensive means to engage students in all phases of satellite development, operation and exploitation through real-world, hands-on research and development experience.

Image above: The twin ELFIN CubeSats. Image Credits: UCLA EPSS.

Small satellites, including CubeSats, are playing an increasingly larger role in exploration, technology demonstration, scientific research and educational investigations at NASA. These miniature satellites provide a low-cost platform for NASA missions, including planetary space exploration; Earth observations; fundamental Earth and space science; and developing precursor science instruments like cutting-edge laser communications, satellite-to-satellite communications and autonomous movement capabilities.

Related article: 

NASA, ULA Launch Mission to Track Earth's Changing Ice

Small Satellite Missions:


Images (mentioned), Video (mentioned), Text, Credits: NASA/Rob Garner/Goddard Space Flight Center, by Miles Hatfield.


Scientists ID Three Causes of Earth's Spin Axis Drift

JPL - Jet Propulsion Laboratory logo.

September 20, 2018

A typical desk globe is designed to be a geometric sphere and to rotate smoothly when you spin it. Our actual planet is far less perfect -- in both shape and in rotation.

Earth is not a perfect sphere. When it rotates on its spin axis -- an imaginary line that passes through the North and South Poles -- it drifts and wobbles. These spin-axis movements are scientifically referred to as "polar motion." Measurements for the 20th century show that the spin axis drifted about 4 inches (10 centimeters) per year. Over the course of a century, that becomes more than 11 yards (10 meters).

Image above: The observed direction of polar motion, shown as a light blue line, compared with the sum (pink line) of the influence of Greenland ice loss (blue), postglacial rebound (yellow) and deep mantle convection (red). The contribution of mantle convection is highly uncertain. Image Credits: NASA/ JPL-Caltech.

Using observational and model-based data spanning the entire 20th century, NASA scientists have for the first time identified three broadly-categorized processes responsible for this drift -- contemporary mass loss primarily in Greenland, glacial rebound, and mantle convection.

"The traditional explanation is that one process, glacial rebound, is responsible for this motion of Earth's spin axis. But recently, many researchers have speculated that other processes could have potentially large effects on it as well," said first author Surendra Adhikari of NASA's Jet Propulsion Laboratory in Pasadena, California. "We assembled models for a suite of processes that are thought to be important for driving the motion of the spin axis. We identified not one but three sets of processes that are crucial -- and melting of the global cryosphere (especially Greenland) over the course of the 20th century is one of them."

In general, the redistribution of mass on and within Earth -- like changes to land, ice sheets, oceans and mantle flow -- affects the planet's rotation. As temperatures increased throughout the 20th century, Greenland's ice mass decreased. In fact, a total of about 7,500 gigatons -- the weight of more than 20 million Empire State Buildings -- of Greenland's ice melted into the ocean during this time period. This makes Greenland one of the top contributors of mass being transferred to the oceans, causing sea level to rise and, consequently, a drift in Earth's spin axis.

While ice melt is occurring in other places (like Antarctica), Greenland's location makes it a more significant contributor to polar motion.

"There is a geometrical effect that if you have a mass that is 45 degrees from the North Pole -- which Greenland is -- or from the South Pole (like Patagonian glaciers), it will have a bigger impact on shifting Earth's spin axis than a mass that is right near the Pole," said coauthor Eric Ivins, also of JPL.

Previous studies identified glacial rebound as the key contributor to long-term polar motion. And what is glacial rebound? During the last ice age, heavy glaciers depressed Earth's surface much like a mattress depresses when you sit on it. As that ice melts, or is removed, the land slowly rises back to its original position. In the new study, which relied heavily on a statistical analysis of such rebound, scientists figured out that glacial rebound is likely to be responsible for only about a third of the polar drift in the 20th century.

The authors argue that mantle convection makes up the final third. Mantle convection is responsible for the movement of tectonic plates on Earth's surface. It is basically the circulation of material in the mantle caused by heat from Earth's core. Ivins describes it as similar to a pot of soup placed on the stove. As the pot, or mantle, heats, the pieces of the soup begin to rise and fall, essentially forming a vertical circulation pattern -- just like the rocks moving through Earth's mantle.

With these three broad contributors identified, scientists can distinguish mass changes and polar motion caused by long-term Earth processes over which we have little control from those caused by climate change. They now know that if Greenland's ice loss accelerates, polar motion likely will, too.

The paper in Earth and Planetary Science Letters is titled "What drives 20th century polar motion?" Besides JPL, coauthor institutions include the German Research Centre for Geosciences, Potsdam; the University of Oslo, Norway; Technical University of Denmark, Kongens Lyngby; the Geological Survey of Denmark and Greenland, Copenhagen, Denmark; and the University of Bremen, Germany. An interactive simulation of how multiple processes contribute to the wobbles in Earth's spin axis is available at:

Image (mentioned), Text, Credits: NASA/JPL/Esprit Smith.


Recent tectonics on Mars

ESA - Mars Express Mission patch.

20 September 2018

These prominent trenches were formed by faults that pulled the planet’s surface apart less than 10 million years ago.

The images were taken by ESA’s Mars Express on 27 January, and capture part of the Cerberus Fossae system in the Elysium Planitia region near the martian equator.

Mars Express view of Cerberus Fossae

The fossae – meaning ‘ditches’ or ‘trenches’ in Latin – stretch for more than 1000 kilometres from the northwest to the southeast.

They cut through impact craters and hills along the way, as well as 10 million year old volcanic plains, indicating the relative youth of their formation.

Cerberus Fossae in context

They vary in width, typically from a few tens of metres to over a kilometre wide, and are thought to be tectonic features originating from faults that stretch the upper layers of the surface apart.

They could be linked to injections of lava at depth deforming the surface above, perhaps originating from the trio of volcanoes that are located to the northwest.

Rounded collapse pits observed in the northern part (north is to the right in the main colour image) indicate an early stage of surface sinking; in other places rounded features can be seen connecting up to create longer cracks.

Perspective view of Cerberus Fossae

Scientists studying this region have speculated that the fractures could rupture the crust to a certain depth, allowing lava or groundwater to escape to the surface.

To the west, as seen in the context image, the Athabasca Valles outflow channel links with the fossae system.

Perspective view of Cerberus Fossae

The dark material seen in the largest crater at the north (right) and around some of the cracks is sand blown by the wind across the martian surface.

Mars Express celebrates 15 years in orbit this year, and scientists are discussing some of the mission's highlights at the European Planetary Science Congress this week in Berlin, Germany.

 Topographic view of Cerberus Fossae

During its mission lifetime it has taken over 40,000 images of Mars and its two moons with the high resolution stereo camera, as well as context images with its Visual Monitoring Camera. It has also collected a vast dataset with its suite of scientific instruments that are analysing the planet from its ionosphere, atmosphere, and interaction with the solar wind, through to its subsurface with radar.

Cerberus Fossae in 3D

Explore all available Mars Express data in ESA’s Planetary Science Archive:

Related links:

European Planetary Science Congress:

Visual Monitoring Camera:

Mars Express:

Images, Text, Credits: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO/NASA MGS MOLA Science Team.

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mercredi 19 septembre 2018

The hunt for leptoquarks is on

CERN - European Organization for Nuclear Research logo.

19 Sep 2018

Image above: A collision event recorded by CMS at the start of the data-taking run of 2018. CMS sifts through such collisions up to 40 million times per second looking for signs of hypothetical particles like leptoquarks (Image: Thomas McCauley/Tai Sakuma/CMS/CERN).

Matter is made of elementary particles, and the Standard Model of particle physics states that these particles occur in two families: leptons (such as electrons and neutrinos) and quarks (which make up protons and neutrons). Under the Standard Model, these two families are totally distinct, with different electric charges and quantum numbers, but have the same number of generations (see image below).

However, some theories that go beyond the Standard Model, including certain “grand unified theories”, predict that leptons and quarks merge at high energies to become leptoquarks. These leptoquarks are proposed in theories attempting to unify the strong, weak and electromagnetic forces.

Such “unifications” are not unusual in physics. Electricity and magnetism were famously unified in the 19th century into a single force known as electromagnetism, via Maxwell’s elegant mathematical formulae. In the case of leptoquarks, these hybrid particles are thought to have the properties of both leptons and quarks, as well as the same number of generations. This would not only allow them to “split” into the two types of particles but would also allow leptons to change into quarks and vice versa. Indeed, anomalies detected by the LHCb experiment as well as by Belle and Babar in measurements of the properties of B mesons could be also explained by the existence of these hypothesised particles.

Image above: The Standard Model of particle physics divides elementary particles of matter into separate families: leptons and quarks. Each family consists of six particles, which are related in pairs, or “generations”. The lightest and most stable particles make up the first generation, whereas the heavier and less stable particles belong to the second and third generations. The six leptons are arranged in three generations – the “electron” and the “electron neutrino”, the “muon” and the “muon neutrino”, and the “tau” and the “tau neutrino”.The six quarks are similarly paired in three generations – the “up quark” and the “down quark” form the first generation, followed by the “charm quark” and “strange quark”, then the “top quark” and “bottom (or beauty) quark”.  (Image: Daniel Dominguez/CERN).

If leptoquarks exist, they would be very heavy and quickly transform, or “decay”, into more stable leptons or quarks. Previous experiments at the SPS and LEP at CERN, HERA at DESY and the Tevatron at Fermilab have looked at decays to first- and second-generation particles. Searches for third-generation leptoquarks (LQ3) were first performed at the Tevatron, and are now being explored at the Large Hadron Collider (LHC).

Since leptoquarks would transform into a lepton and a quark, LHC searchers look for telltale signatures in the distributions of these “decay products”. In the case of third-generation leptoquarks, the lepton could be a tau or a tau neutrino while the quark could be a top or bottom.

In a recent paper, using data collected in 2016 at a collision energy of 13 TeV, the Compact Muon Solenoid (CMS) collaboration at the LHC presented the results of searches for third-generation leptoquarks, where every LQ3 produced in the collisions initially transformed into a tau-top pair.

Because colliders produce particles and antiparticles at the same time, CMS specifically searched for the presence of leptoquark-antileptoquark pairs in collision events containing the remnants of a top quark, an antitop quark, a tau lepton and an antitau lepton. Further, because leptoquarks have never been seen before and their properties remain a mystery, physicists rely on sophisticated calculations based on known parameters to look for them. These parameters include the energy of the collisions and expected background levels, constrained by the possible values for the mass and spin of the hypothetical particle. Through these calculations, the scientists can estimate how many leptoquarks might have been produced in a particular data set of proton-proton collisions and how many might have been transformed into the end products their detectors can look for.

Large Hadron Collider (LHC). Animation Credit: CERN

“Leptoquarks have became one of the most tantalising ideas for extending our calculations, as they make it possible to explain several observed anomalies. At the LHC we are making every effort to either prove or exclude their existence,” says Roman Kogler, a physicist on CMS who worked on this search.

After sifting through collision events looking for specific characteristics, CMS saw no excess in the data that might point to the existence of third-generation leptoquarks. The scientists were therefore able to conclude that any LQ3 that transform exclusively to a top-tau pair would need to be at least 900 GeV in mass, or around five times heavier than the top quark, the heaviest particle we have observed.

The limits placed by CMS on the mass of third-generation leptoquarks are the tightest so far. CMS has also searched for third-generation leptoquarks that transform into a tau lepton and a bottom quark, concluding that such leptoquarks would need to be at least 740 GeV in mass. However, it is important to note that this result comes from the examination of only a fraction of LHC data at 13 TeV, from 2016. Further searches from CMS and ATLAS that take into account data from 2017 as well as the forthcoming run of 2018 will ensure that the LHC can continue to test theories about the fundamental nature of our universe.

See also “CMS searches for third-generation leptoquarks” in the CERN Courier’s April 2018 issue:


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.

The instruments used at CERN are particle accelerators and detectors. Accelerators boost beams of particles to high energies before they are made to collide with each other or with stationary targets. Detectors observe and record the results of these collisions.

Founded in 1954, the CERN Laboratory sits astride the Franco–Swiss border near Geneva. It was one of Europe’s first joint ventures and now has 22 Member States.

Related links:

Standard Model of particle physics:

LHCb experiment:

ATLAS experiment:



Compact Muon Solenoid (CMS) collaboration:

Large Hadron Collider (LHC):

CERN paper:



For more information about European Organization for Nuclear Research (CERN),  Visit:

Images (mentioned), Animation (mentioned), Text, Credits: CERN/Achintya Rao.


Physics, Human Research on Lab as Japan Announces Launch Date

ISS - Expedition 56 Mission patch.

September 19, 2018

Physics science and human research continues unabated aboard the International Space Station as NASA and its partners seek to understand the impacts of living in space. Meanwhile, Japan announced a new launch date for its HTV-7 cargo mission to resupply the Expedition 56 crew.

Astronaut Alexander Gerst of ESA (European Space Agency) has been exploring for several weeks now whether a custom designed t-shirt can provide comfort and thermal efficiency during a space workout. He has also been testing a wearable device that measures cardio-pulmonary activity during exercise.

Image above: NASA astronaut Serena Auñón-Chancellor poses with a U.S. spacesuit inside the U.S. Quest Airlock. The spacesuit helmet’s visor is coated with a thin layer of gold that filters out the sun’s harmful rays during spacewalks. Image Credit: NASA.

NASA astronauts Ricky Arnold and Serena Auñón-Chancellor worked on separate science gear today that enables research into flames, fuels and high temperatures in space. Arnold spent most of Wednesday replacing experiment hardware inside the Combustion Integrated Rack. Auñón-Chancellor removed samples from inside the Electrostatic Levitation Furnace to observe changes in their thermo-physical properties.

JAXA (Japan Aerospace Exploration Agency) announced early today that it will attempt to launch its HTV-7 resupply ship, also known as the Kounotori, Friday at 2:15 p.m. EDT to the station. The Kounotori is due to arrive at the station Tuesday loaded with over five tons of cargo, including new science experiments and science hardware.

Image above: Sunset over Caribean Sea, seen by EarthCam on ISS, speed: 27'600 Km/h, altitude: 408,48 Km, image captured by Roland Berga (on Earth in Switzerland) from International Space Station (ISS) using ISS-HD Live application with EarthCam's from ISS on September 19, 2018 at 22:24 UTC. Image Credits: Aerospace/Roland Berga.

Commander Drew Feustel and will be in the cupola Tuesday, with Auñón-Chancellor as his backup, to command the Canadarm2 robotic arm to capture the Kounotori at 8:05 a.m. The duo has been training for the Kounotori’s arrival for several weeks practicing on a computer rendezvous procedures and robotics maneuvers. NASA TV will broadcast the Kounotori launch and capture activities live.

Related links:

Expedition 56:

Cardio-pulmonary activity:

Combustion Integrated Rack:

Electrostatic Levitation Furnace:

Science hardware:


Space Station Research and Technology:

International Space Station (ISS):

Image (mentione), Text, Credits: NASA/Mark Garcia/ Aerospace/Roland Berga.

Best regards,

Illuminating First Light Data from Parker Solar Probe

NASA - Parker Solar Probe Mission patch.

September 19, 2018

Just over a month into its mission, Parker Solar Probe has returned first-light data from each of its four instrument suites. These early observations – while not yet examples of the key science observations Parker Solar Probe will take closer to the Sun – show that each of the instruments is working well. The instruments work in tandem to measure the Sun’s electric and magnetic fields, particles from the Sun and the solar wind, and capture images of the environment around the spacecraft.

Parker Solar Probe. Animation Credit: NASA

“All instruments returned data that not only serves for calibration, but also captures glimpses of what we expect them to measure near the Sun to solve the mysteries of the solar atmosphere, the corona,” said Nour Raouafi, Parker Solar Probe project scientist at the Johns Hopkins University Applied Physics Lab in Laurel, Maryland.

The mission’s first close approach to the Sun will be in November 2018, but even now, the instruments are able to gather measurements of what’s happening in the solar wind closer to Earth. Let’s take a look at what they’ve seen so far.

WISPR (Wide-field Imager for Solar Probe)

As the only imager on Parker Solar Probe, WISPR will provide the clearest-yet glimpse of the solar wind from within the Sun’s corona. Comprising two telescopes, WISPR sits behind the heat shield between two antennae from the FIELDS instrument suite. The telescopes were covered by a protective door during launch to keep them safe.

WISPR was turned on in early September 2018 and took closed-door test images for calibration. On Sept. 9, WISPR’s door was opened, allowing the instrument to take the first images during its journey to the Sun.

Image above: The right side of this image — from WISPR’s inner telescope — has a 40-degree field of view, with its right edge 58.5 degrees from the Sun’s center. The left side of the image is from WISPR’s outer telescope, which has a 58-degree field of view and extends to about 160 degrees from the Sun. There is a parallax of about 13 degrees in the apparent position of the Sun as viewed from Earth and from Parker Solar Probe. Image Credits: NASA/Naval Research Laboratory/Parker Solar Probe.

Russ Howard, WISPR principal investigator from the Naval Research Laboratory, studied the images to determine the instrument was pointing as expected, using celestial landmarks as a guide.

“There is a very distinctive cluster of stars on the overlap of the two images. The brightest is the star Antares-alpha, which is in the constellation Scorpius and is about 90 degrees from the Sun,” said Howard.

The Sun, not visible in the image, is far off to the right of the image’s right edge. The planet Jupiter is visible in the image captured by WISPR’s inner telescope — it’s the bright object slightly right of center in the right-hand panel of the image.

“The left side of the photo shows a beautiful image of the Milky Way, looking at the galactic center,” said Howard.

The exposure time – i.e. the length of time that light was gathered for this image, an interval which can be shortened or lengthened to make the image darker or brighter – is on the lower end, and there’s a reason: “We intentionally wanted to be on the low side in case there was something very bright when we first turned on, but it is primarily because we are looking so far from the Sun,” explains Howard.

As the spacecraft approaches the Sun, its orientation will change, and so will WISPR’s images. With each solar orbit, WISPR will capture images of the structures flowing out from the corona. While measurements have been made before by other instruments at a distance of 1 AU – or approximately 93 million miles – WISPR will get much closer, about 95% of the way to the Sun from Earth, dramatically increasing the ability to see what’s occurring in that region with a much finer scale than ever before and providing a more pristine picture of the solar corona.

ISʘIS (Integrated Science Investigation of the Sun)

Image Credits: NASA/Princeton University/Parker Solar Probe.

ISʘIS (pronounced “ee-sis” and including the symbol for the Sun in its acronym) measures high-energy particles associated solar activity like flares and coronal mass ejections. (The mission’s other particle instrument suite, SWEAP, focuses on low-energy particles that make up the solar wind.) ISʘIS’ two Energetic Particle Instruments cover a range of energies for these activity-driven particles: EPI-Lo focuses on the lower end of the energy spectrum, while EPI-Hi measures the more energetic particles. Both instruments have gathered data under low voltage, making sure their detectors work as expected. As Parker Solar Probe approaches the Sun, they will be fully powered on to measure particles within the Sun’s corona.

EPI-Lo’s initial data, on the left, shows background cosmic rays, particles that were energized and came rocketing into our solar system from elsewhere in the galaxy. As EPI-Lo’s high voltage is turned on and Parker Solar Probe gets closer to the Sun, the particles measured will shift toward solar energetic particles, which are accelerated in bursts and come streaming out from the Sun and corona.

On the right, data from EPI-Hi shows detections of both hydrogen and helium particles from its lower-energy telescopes. Nearer to the Sun, scientists expect to see many more of these particles — along with heavier elements — as well as some particles with much higher energies, especially during solar energetic particle events.

“The ISʘIS team is delighted with instrument turn-on so far,” said David McComas, Professor of Astrophysical Sciences at Princeton University and principal investigator of the ISʘIS instrument suite. “There are a few more steps to go, but so far everything looks great!”


The FIELDS instrument suite aboard Parker Solar Probe captures the scale and shape of electric and magnetic fields in the Sun’s atmosphere. These are key measurements to understanding why the Sun’s corona is hundreds of times hotter than its surface below.

Graphic Credits: NASA/UC Berkeley/Parker Solar Probe.

FIELDS’ sensors include four two-meter electric field antennas — mounted at the front of the spacecraft, extending beyond the heat shield and exposed to the full brunt of the solar environment — as well as three magnetometers and a fifth, shorter electric field antenna mounted on a boom that extends from the back of the spacecraft.

The data above, gathered during the boom deployment shortly after the spacecraft’s launch in August, shows how the magnetic field changes as the boom swung away from Parker Solar Probe. The early data is the magnetic field of the spacecraft itself, and the instruments measured a sharp drop in the magnetic field as the boom extended away from the spacecraft. Post-deployment, the instruments are measuring the magnetic field in the solar wind — illustrating the very reason such sensors need to be held out far from the spacecraft.

Image Credits: NASA/UC Berkeley/Parker Solar Probe/Wind.

In early September, the four electric field antennas on the front of the spacecraft were successfully deployed — and almost immediately observed the signatures of a solar flare.

“During its commissioning time, FIELDS measured its first radio burst from a solar flare,” said principal investigator Stuart Bale, of the Space Sciences Laboratory at the University of California, Berkeley. Such bursts of radio waves can be detected during solar flares — enormous eruptions of energy and light — and are associated with the energetic electrons that flares release. This radio burst was captured by the FIELDS electric field antennas, shown above with measurements from NASA’s Wind spacecraft (on the top) for comparison.

“FIELDS is one of the most comprehensive fields and waves suites ever flown in space, and it is performing beautifully,” said Bale.

SWEAP (Solar Wind Electrons Alphas and Protons)

Image Credits: NASA/University of Michigan/Parker Solar Probe.

The SWEAP suite includes three instruments: Two Solar Probe Analyzers measure electrons and ions in the solar wind, while the Solar Probe Cup sticks out from behind Parker Solar Probe’s heat shield to measure the solar wind directly as it streams off the Sun. After opening covers, turning on high voltages and running internal diagnostics, all three instruments caught glimpses of the solar wind itself.

Because of Parker Solar Probe’s position and orientation, the science team expected that Solar Probe Cup would mostly measure background noise at first, without picking up the solar wind. But just after the instrument was powered on, a sudden, intense gust of solar wind blew into the cup, visible in the data as the red streak. As the spacecraft approaches the Sun, such observations will be Solar Probe Cup’s bread and butter — and will hopefully reveal new information about the processes that heat and accelerate the solar wind.

Image Credits: NASA/University of Michigan/Parker Solar Probe.

The two Solar Probe Analyzers (SPAN) also caught early peeks of the solar wind. During commissioning, the team turned the spacecraft so that SPAN-A — one of the two SPAN instruments — was exposed to the solar wind directly. It captured about 20 minutes’ worth of data (right), including measurements of solar wind ions (top) and electrons (bottom). While SPAN-A and its sister instrument, SPAN-B, will measure solar wind electrons throughout the mission, the spacecraft’s orientation now means that SPAN-A will likely go several more years before it captures such ion measurements again. This is because solar wind electrons can be measured from any direction, as their low mass and high temperature make their motion much more random, while the much heavier solar wind ions follow a relatively direct path out from the Sun.

“SWEAP’s solar wind and corona plasma instrument performance has been very promising,” said Justin Kasper, principal investigator of the SWEAP instrument suite at University of Michigan.  “Our preliminary results just after turn-on suggest we have a set of highly sensitive instruments that will allow us to do amazing science close to the Sun.”

Download these images in HD formats from NASA’s Scientific Visualization Studio:

Related links:

NASA’s Wind spacecraft:

Parker Solar Probe:

Images (mentioned), Graphic (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Sarah Frazier (NASA) & Justyna Surowiec (APL)/Johns Hopkins University Applied Physics Lab.