samedi 18 mai 2019

Asteroid Apophis 2029 It's Coming Very Close to the Earth

Asteroid Watch.

May 18, 2019

Asteroids are out there, even if you can't always see them.

Image above: Artist illustration of the asteroid Apophis making a close flyby of Earth. Image Credit: European Space Agency (ESA).

Want some naked-eye proof? It's coming, in the form of a mountain of space rock named Apophis, for the Egyptian god of chaos; his task is to prevent the sun from rising.

Stretching three-and-a-half football fields long, Apophis will cruise within 19,000 miles of Earth—the closest this large an asteroid has come in recorded history. Apophis will swing inside our ring of geosynchronous satellites on April 13, 2029.

And yes, that is a Friday.

Animation above: This animation shows the distance between the Apophis asteroid and Earth at the time of the asteroid’s closest approach in 2029. The blue dots are manmade satellites orbiting our planet, and the pink represents the International Space Station. Animation Credits: NASA/JPL-Caltech.

But don't worry, NASA has it all figured. Any bad luck that may befall you on that day won't come from Apophis—probably. An earlier worst-case prediction that gave a 2.7 percent chance of Apophis striking the Earth has since been downgraded to practically nil. Actually, that's an upgrade.

Apophis is a Sparkle in NASA's Eye

In fact, NASA scientists look forward to Apophis' near miss. Given a decade to prepare, NASA might even send a robotic probe to rendezvous with the rock. At minimum, it's an incredible opportunity to make close-up observations of a large asteroid. Apophis is large enough, and will be close enough, to see with our bare eyes, so Earth-based optical and radio telescopes will have an unprecedented view of the spectacle.

Image above: Astronomers discovered asteroid Apophis on June 19, 2004. At first, when its orbit was not well understood, there was brief concern it had the potential to strike Earth in this century. Image Credits: UH/IA/NASA.

At the 2019 Planetary Defense Conference held in Maryland this April, scientists brainstormed all the possible ways to take advantage of a flyby that others might see only as a narrowly averted disaster.

NASA has used radio telescopes before to produce rudimentary images of some passing asteroids, though these were either smaller ones or much farther away. The last time any rock this size passed close to Earth was in 2001, the asteroid 2017 VW13. That one is estimated to have passed within 76,000 miles, a third of the distance to the moon. And, since it wasn't discovered until 2017, no one even noticed it fly by!

God of Chaos

Apophis is classified today as a "Potentially Hazardous Asteroid" (PHA). This means that it periodically crosses Earth's orbital path, and is large enough to do some major damage if it were to hit us.

Far from being an infrequent visitor from deep space as many comets are, coming around only every few decades or centuries, Apophis is a denizen of the inner solar system. Its 324-day orbit carries it from just outside Earth's orbit at its farthest point from the sun, almost to the orbit of Venus at its closest.

Image above: Diagram showing the orbits of the planets of the inner solar system, and the asteroid Apophis. Image Credits: NASA/JPL.

You might think that because Apophis crosses Earth's orbit more than once each year, the chance of collision is an ever-present threat.

However, most of the time when Apophis crosses our path, Earth is at a different point in its orbit. It's only those times when our orbital positions sync up that there's any chance of bumping into each other. Think of a carnival carousel and that brass ring you try to grab each time your horse passes by it. You only have a shot at getting that ring if it swings close when you pass—and even then there's no guarantee.

April 13, 2029 is one of those match-ups, and scientists are keenly eyeing the brass ring of new discovery that will be briefly within their reach.

What Are the Chances?

While small objects pass close to Earth on a routine basis, and even collide with us more often than you might think, most go unnoticed. Three quarters of them fall over open ocean, most of the rest over sparsely populated land. And those that don't break up in the atmosphere have limited effects when they hit the water or the ground anyway.

Larger, more dangerous rocks make appearances with far less frequency—and the bigger they are, the rarer the encounter.

Image above: A model of the shape of asteroid Apophis, generated from its light curve and assuming that all areas of the asteroid have a similar albedo and reflectivity, via the Database of Asteroid Models from Inversion Techniques (DAMIT) and and Wikimedia Commons.

Notable impacts in recent history include the Tunguska comet or meteorite impact in Siberia in 1908, and the Chelyabinsk event in Russia in 2013. Both were smaller than Apophis, but were relatively large objects: between 200 and 600 feet across in the case of Tunguska, and about 66 feet for Chelyabinsk. They exploded in Earth's atmosphere, producing significant effects on the ground below, though no known fatalities.

Larger collisions with greater regional and even global effects can be found in prehistoric times, such as the impact that formed Barringer Crater (aka "Meteor Crater") in Arizona 50,000 years ago.

To find a "dinosaur killer" impact event you'd have to look all the way back to, well, the dinosaur killer impact, 66 million years ago. The asteroid that contributed to ending the dinosaurs's long reign on Earth, which struck the northern end of the Yucatan Peninsula near Chicxulub, Mexico, was probably six miles across.

Image above: Diagram detailing the remnants of the Chicxulub impact crater on the Yucatan Peninsula. Though now buried under jungle and ocean sediment, evidence of the crater can be found through radar imaging and mineral analysis of rock samples. Image Credits: NASA/JPL-Caltech/David Fuchs.

Defending Against Near Earth Objects

Fortunately, we aren't completely in the dark about the dangers posed by Near-Earth Objects. We're also not completely helpless when it comes to defending our planet from them.

For years now, an international coalition of observers and researchers have collaborated to find, measure, and track Near-Earth Objects. The data they collect are used to calculate the probability of a collision, and to predict the level of damage in the event of a hit. (Related articles links).

Ultimately, a major asteroid impact with Earth is a matter of when, not if. But the good news is that none are predicted in the foreseeable future.

Asteroid impact on Earth

The current approach to planetary defense hinges on the idea that the further in advance we can predict an impact, the more time we have to do something about it. If we know it's coming years before the fact, a tiny "nudge" to the asteroid's trajectory can make the difference between a catastrophic impact and a harmless near miss.

What About Apophis' Next Flyby?

The probability of Apophis hitting the Earth in 2029 has been practically ruled out. Its close passage through Earth's gravitational field, though, will result in a change in its orbital path, so careful observations of the flyby will yield more than scientific discovery, it will let us make more precise collision predictions for future encounters.

As things stand now, Apophis will make another close encounter with Earth in 2036, but will come no closer than 14 million miles. Beyond that, the chance of it hitting us anytime between 2060 and 2105 is 1 in 110,000.

Astronomers will be watching!

For more information about asteroids and near-Earth objects, visit: Updates about near-Earth objects are also available by following AsteroidWatch on Twitter at

Bottom line: Astronomers met on April 30, 2019, at the Planetary Defense Conference to discuss plans to observe asteroid 99942 Apophis, a relatively large asteroid that’ll sweep past Earth safely – but rather closely – a decade from now.

Related articles:

NASA’s First Planetary Defense Technology Demonstration to Collide with Asteroid in 2022

Earth vs. asteroids: humans strike back

Work begins on ESA's part of planetary defence test

Related links:

2019 Planetary Defense Conference:

Potentially Hazardous Asteroid" (PHA):

Near-Earth Objects:

Images (mentioned), Animation, Text, Credits: NASA/KQED Science/Ben Burress/ Aerospace/Roland Berga.


Long March-3C launches BeiDou-2 GEO-8 satellite

BeiDou Navigation Satellite System logo.

May 18, 2019

Long March-3C launches BeiDou-2 GEO-8 satellite. Image Credit: Xinhua

A Long March-3C launch vehicle launched the BeiDou-2 GEO-8 navigation satellite from the Xichang Satellite Launch Center, Sichuan Province, China, on 17 May2019, at 15:48 UTC (23:48 local time).

Long March-3C launches BeiDou-2 GEO-8 satellite

The new satellite is the fourth BeiDou-2 backup satellite and the 45th satellite of the BeiDou satellite family. According to official sources, the satellite entered its designated orbit. Long March 3C rocket launches a satellite for the country’s Beidou navigation network toward geostationary orbit.

Render of a BeiDou-3 satellite by J. Huart

The MEO satellites are the Medium Earth Orbit component of the 3rd phase of the Chinese Beidou (Compass) satellite navigation system. The satellites are part of a fleet that will expand the system to a global navigation coverage.

The Beidou Phase III system includes the migration of its civil Beidou 1 or B1 signal from 1561.098 MHz to a frequency centered at 1575.42 MHz – the same as the GPS L1 and Galileo E1 civil signals – and its transformation from a quadrature phase shift keying (QPSK) modulation to a multiplexed binary offset carrier (MBOC) modulation similar to the future GPS L1C and Galileo’s E1.

Image above: BeiDou Constellation Overview (Compass Navigation Satellite System). Image Credit: CASC.

The Radio Navigation Satellite Service (RNSS) is very similar to that provided by GPS and Galileo and is designed to achieve similar performances.

For more information about Beidou navigation system:

For more information about China Aerospace Science and Technology Corporation (CASC):

Images (mentioned), Video, Text, Credits: CASC/Beidou/China Central Television (CCTV)/SciNews/ Aerospace/Roland Berga.

Best regards,

The first step on Mars planned for 2039

Astronaut - From the Moon to Mars and Beyond logo.

May 18, 2019

On December 11, 2017, US President Donald Trump signed a directive ordering NASA to prepare the return of astronauts to the moon, "followed by human missions to Mars and other destinations."

The date fixed by NASA is 2024 for the Moon and 2033 for March, but among the experts and industrialists of the American space sector, the date of 2033 seems highly unlikely, unless a national effort Herculean, the magnitude of Apollo program in the 1960s.

This week, NASA boss Jim Bridenstine said: "The Moon is our test bed for our future mission to Mars at the seventh" People on Mars "conference in Washington. That's why we go to the moon. "

Moon to Mars

Two days later, during a session at the same site devoted to surface operations on Mars, the head of the laboratory developing future space dwellings at Houston's legendary Johnson Center explained that the problem was not technological.

"A lot of people want us to have an Apollo moment, a president get up like Kennedy and take the whole country behind him," said Robert Howard. "With this impulse, we could go there in 2027. But I do not believe it. With our current approach, we will be lucky if we get there before 2037 ". "And if I was really pessimistic (...) I would say the 2060s," he said.

Isolated humans

Everything remains to design, build, test and retest, rockets to vehicles through the method to grow salads.

The one-way trip will take six months at least, as opposed to three days for the moon. The whole mission could last two years, because Mars does not get close to the Earth until every 26 months: you have to sit on these windows.

It will be necessary to design protections for astronauts against solar and cosmic radiation for such a long time, said Julie Robinson, Chief Scientist for the International Space Station (ISS).

"A second problem is the feeding system," she said. The concepts proposed so far "are not small enough to go to Mars". Not to mention the possibility of a medical emergency: the astronauts will have to learn how to manage any accident themselves, because the rescue will be too far away.

"One big topic is space suits," said Jennifer Heldmann of NASA's Ames Research Center. She recalls that the Apollo astronauts had complained a lot of gloves, too inflated and exhausting any manipulation.

New NASA Position to Focus on Moon's Exploration, Mars and Worlds Beyond

In Houston, NASA is developing a new combination, the first in 40 years, called xEMU, but it will only be tested in the ISS in a few years. And Mars is not the moon. Dust will be a big problem. Apollo's astronauts returned covered with lunar dust in their module. Blocking it will be crucial for those who will spend months or a year on the red planet.

The techniques of exploiting the resources of the Martian soil to extract the water, the oxygen and the fuels necessary for the humans do not exist yet - it should be tested on the Moon by the end of this decade.

Finally, there is the most fundamental question: how will some humans psychologically bear being confined and isolated for two years?

It will not be possible to communicate in real time with "mission control" in Houston: radio communications will take between 4 and 24 minutes between the two planets, one way. NASA is planning delayed communication exercises in the coming years in the ISS.

NASA - We Are Going

Artificial intelligence will also need to be developed to help and guide astronauts without ground intervention. One researcher studied in detail the feasibility of Mars landing in 2033, in a report for NASA in February. She declared the goal "unfeasible".

"It's not just a budget issue," said expert Bhavya Lal of the Science & Technology Policy Institute this week. "It's a question of organizational capacity: how much can NASA do at the same time?" The most realistic date, according to her, is 2039.

Related article:

Sending American Astronauts to Moon in 2024: NASA Challenge Accepts

Related links:

National Aeronautics and Space Administration (NASA):

Space Policy Directive-1:

Moon to Mars:

Images, Video, Text, Credits: AFP/NASA/ Aerospace/Roland Berga.


vendredi 17 mai 2019

50 Years Ago: Apollo 10 to Sort Out the Unknowns

NASA - Apollo 10 Mission patch.

May 17, 2019

As Commander Thomas P. Stafford stated during a preflight press conference, Apollo 10 was planned to “sort out all the unknowns” to make the Moon landing possible. Stafford, Command Module Pilot (CMP) John W. Young, and Lunar Module Pilot (LMP) Eugene A. Cernan, were strapped into their Command Module (CM) perched atop a Saturn V rocket and lifted off precisely on time at 12:49 PM EDT on May 18, 1969. Their launch was the first from Pad B at Kennedy Space Center’s (KSC) Launch Complex 39. Their mission was a dress rehearsal for the lunar landing mission, a goal President John F. Kennedy set for the nation eight years earlier. Among the spectators on hand to observe the historic launch were Vice President Spiro T. Agnew, former Vice President Hubert H. Humphrey, and King Baudouin and Queen Fabiola of Belgium.

Images above: Up: Apollo 10 crew of (left to right) Cernan, Young, and Stafford pose in front of their Saturn V rocket at Launch Pad 39B. Middle: Apollo 10 crew patch. Down: Launch of Apollo 10. Images Credit: NASA.

Three and a half miles away, in the Launch Control Center’s Firing Room 3, controllers had monitored the countdown and the first few seconds of the liftoff. As the rocket cleared the launch tower, Mission Control at the Manned Spacecraft Center (MSC), now the Johnson Space Center in Houston, took over monitoring the flight. There, three teams of controllers working in eight-hour shifts watched over all aspects of the mission until splashdown. Flight Directors Glynn S. Lunney and Gerald D. Griffin led the first shift, Milton L. Windler the second, and M.P. “Pete” Frank the third. The capsule communicator, or Capcom, the astronaut in Mission Control who spoke directly with the crew, during the launch was Charles M. Duke. The other Capcoms during the mission were Joe H. Engle, Jack R. Lousma, and Bruce McCandless. Apollo 10 backup CMP Donn F. Eisele and backup LMP Edgar D. Mitchell also briefly took over Capcom duties during the mission.

Images above: Up: Apollo 10 astronauts (front to back) Stafford, Young, and Cernan preparing to leave the Manned Spacecraft Operations Building on their way to the launch pad. Down Mission Control in Houston during the first day of the Apollo 10 mission: seated in foreground left to right are Flight Directors Lunney and Griffin. Images Credit: NASA.

The three stages of the Saturn V placed the Apollo 10 spacecraft, at 98,273 pounds the heaviest ever launched, into a temporary parking orbit around the Earth, still attached to its S-IVB third stage. Two and a half hours later, after the ground and crew verified that all systems aboard the spacecraft were functioning normally, Duke called up, “10, you’re go for TLI,” the Trans-Lunar Injection. The S-IVB fired for 5 minutes and 43 seconds, adding more than 7,000 miles per hour to the spacecraft’s velocity, enough to send Apollo 10 toward the Moon. The engine burn was so precise that it exceeded the expected velocity increase by a mere 0.4 mile per hour! With such a precise flight path, only one of the planned four midcourse corrections were needed.

Images above: Up: The crew broadcast live color television images of Snoopy during the Transposition and Docking Maneuver. Down: View of the Earth during a live color TV broadcast. Images Credit: NASA.

To facilitate communications when the two spacecraft were flying independently, the crew designated their CM Charlie Brown and the Lunar Module (LM) Snoopy, after characters in the Peanuts© comic strip by Charles M. Schulz. Thirty minutes after the TLI burn, the crew separated Charlie Brown from the S-IVB, with Snoopy still snuggled atop the third stage. Young guided Charlie Brown about 150 feet away, turned the spacecraft around, then flew it to dock with Snoopy, completing the transposition and docking maneuver. Viewers received the first color TV images from space, of the S-IVB and Snoopy as Young brought Charlie Brown in for the docking. Duke exclaimed, “It’s looking great!  The resolution is fantastic!” This first color TV transmission lasted 22 minutes, and resumed about 30 minutes later as springs ejected Snoopy, firmly docked with Charlie Brown, from the S-IVB, with Stafford exclaiming, “Snoopy’s coming out of the doghouse.” By this time, Apollo 10 was more than 13,000 miles away from Earth, but its velocity was decreasing as the home planet’s gravity inexorably tugged at the spacecraft.

Images above: Color television views of (Up to Down) Stafford, Cernan, and Young, during one of the broadcasts on the first mission day. Images Credits: NASA/Apollo 10 Crew.

Less than an hour after separating from the S-IVB, Apollo 10 fired its Service Propulsion System (SPS) engine for about three seconds to separate from the spent rocket stage. The S-IVB fired its remaining fuel to send it past the Moon three days later and on into solar orbit. The crew then treated television viewers to another color broadcast by showing them the home planet from about 25,000 miles away. The broadcast ended after about 13 minutes as the crew settled down for some housekeeping. And before their first sleep period in space, the crew treated viewers on the ground with another 24-minute TV transmission, first of the home planet and then some views of themselves in the cabin. Capcom McCandless commented, “It’s really great. The colors are fantastic.” After the transmission they finally took off the spacesuits they had been wearing since several hours before launch. After eating dinner, the next task for them was to place their spacecraft in the Passive Thermal Control (PTC) attitude, during which it rotated slowly about its longitudinal axis to even out the extreme temperatures in space, making three rotations every hour. For this reason, the attitude is often referred to as barbecue mode.

Images above: Up: View of Mission Control during one of the TV broadcasts from Apollo 10. Middle: Capcoms (left to right) Duke, McCandless, and Engle conferring during the mission. Down: Barbara Cernan (right) in the Mission Control viewing room, accompanied by Flight Director Lunney. Images Credit: NASA.

For the next two days, the mission continued relatively event free. The crew conducted six more TV broadcasts showing the ground views of the ever-shrinking Earth and more interior shots of the crew. By some estimates, more than a billion people watched at least some of the Apollo 10 broadcasts. The crew completed the only mid-course correction needed, a seven-second firing of the SPS engine that adjusted the trajectory for the proper altitude above the Moon for the Lunar Orbit Insertion (LOI) burn. Along the way, the astronauts were able to sight the discarded S-IVB stage, about 4,000 miles away, travelling in a roughly parallel path that took it past the Moon and into solar orbit. About 62 hours after launch, they crossed into the Moon’s gravitational sphere of influence and their speed began to increase. At 72 hours 55 minutes and still about 9,000 miles from the Moon, Apollo 10 passed into the darkness of the lunar shadow. The only external light came from Earthshine, sunlight reflected from the Earth, and bright enough to illuminate their LM Snoopy. Less than three hours later, Apollo 10 passed behind the Moon and communications with Earth was cut off. The LOI burn, the firing of the SPS engine to put Apollo 10 into lunar orbit, would take place seven minutes later but behind the Moon, and only the three astronauts would know if the burn was successful until the spacecraft reappeared and communications with Earth was reestablished.

Related links:

Apollo 10:

NASA History:

Images (mentioned), Text, Credits: NASA/JSC/John Uri.

Best regards,

Multitude of Space Biology Research as Crew Looks to Next Spacewalk

ISS - Expedition 59 Mission patch.

May 17, 2019

Four Expedition 59 astronauts spent Friday investigating a multitude of space biology phenomena while two cosmonauts continued preparing for an upcoming spacewalk. International Space Station hardware is also ready for return to Earth inside the SpaceX Dragon resupply ship.

The crew is exploring how space impacts a variety of microscopic physiological processes today to get humans ready to go to the Moon in 2024. DNA, pathogens and microalgae as well as their benefits and risks to astronauts are just some of the microbiological systems scientists are studying in space.

Image above: The Canadarm2 robotic arm with its robotic hand, also known as Dextre, attached for fine-tuned robotics work extends across the frame as the International Space Station orbited 256 miles above the Atlantic Ocean. The SpaceX Dragon resupply ship is pictured at right berthed to the Harmony module. Image Credit: NASA.

The Bio-Analyzer is a new device from the Canadian Space Agency (CSA) being tested aboard the space station for its ability to process and analyze biological samples quickly. CSA astronaut David Saint-Jacques added his blood samples to the biomedical device today so doctors could check his biomarkers from the ground.

NASA astronaut Christina Koch studied a pair of yeast strains today using the miniPCR hardware for the Genes In Space-6 study. The experiment is exploring how space radiation damages DNA and how the cell repair mechanism works in microgravity. Koch later tended to plants grown inside the Veggie PONDS botany facility.

More research into why pathogens become more virulent in space continued today as Flight Engineer Nick Hague processed culture samples for the microbiology study. Hague also checked on microalgae sample packs that may serve as a dietary supplement for future astronauts.

Image above: The Gulf and eastern coasts of the United States feature prominently in this well-lit nighttime view of North America. Image Credit: NASA.

Hague also configured a variety of space biology hardware, both large and small, ensuring critical research operations continue successfully on the orbital lab. He first worked on a pair of refrigerator-sized Human Research Facility racks before checking out the shoebox-sized TangoLab-1 facility that enables a variety of tissue, cell and botany investigations.

Anne McClain of NASA turned her attention Friday to old hardware disconnected during a spacewalk earlier this year. She will retrieve a failed Battery Charge Discharge Unit (BCDU) resting outside the Kibo laboratory module’s airlock and bring it inside the station. The Canadarm2’s robotic hand, known as Dextre, removed the BCDU early Thursday from a truss structure logistics carrier and placed it outside Kibo. The BCDU will be packed aboard the SpaceX Dragon cargo craft for analysis after it returns to Earth June 3.

International Space Station (ISS). Animation Credit: NASA

Two cosmonauts are getting ready for the fourth station spacewalk this year scheduled to take place May 29. Commander Oleg Kononenko and Flight Engineer Alexey Ovchinin tagged up with Russian spacewalk specialists on the ground today for assistance setting up their Orlan spacesuits. The duo will remove experiments, sample station surfaces and jettison obsolete hardware during their six-hour excursion.

Related links:

Expedition 59:

SpaceX Dragon:


Genes In Space-6:

Veggie PONDS:


Human Research Facility:


Kibo laboratory module:


Moon and beyond:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

LS2 Report: consolidating the energy extraction systems of LHC superconducting magnet circuits

CERN - European Organization for Nuclear Research logo.

17 May, 2019

In the LHC, 1232 superconducting dipole magnets and 392 quadrupole magnets guide and focus the beams around the accelerator’s 27-kilometre ring, which is divided into eight sectors. These magnets operate at very low temperatures – 1.9 K or −271.3 °C – where even a tiny amount of energy released inside a magnet can warm its windings to above the critical temperature, causing the loss of superconductivity: this is called a quench. When this happens, the energy stored in the affected magnet has to be safely extracted in a short time to avoid damage to the magnet coil.

To do so, two protection elements are activated: at the level of the quenching magnet, a diode diverts the current into a parallel by-pass circuit in less than a second; at the level of the circuit, 13 kA energy extraction systems absorb the energy of the whole magnet circuit in a few minutes. There are equivalent extraction systems installed for about 200 corrector circuits with currents up to 600 A.

Image above: The LS2 team from the NRC Kurchatov-IHEP Institute, Protvino, Russia, with a 13 kA energy extraction system (Image: NRC Kurchatov-IHEP Institute).

“In the framework of a long-lasting and fruitful collaboration between CERN and the Russian Federation, energy extraction systems for quench protection of the LHC superconducting magnets were designed in close partnership with two Russian institutes, the NRC Kurchatov-IHEP Institute in Protvino for the 13 kA systems and the Budker Institute in Novosibirsk for the 600 A systems. Russian industry was involved in the manufacturing of the parts of these systems,” explains Félix Rodríguez Mateos, leader of the Electrical Engineering (EE) section in the Machine Protection and Electrical Integrity (MPE) group of CERN’s Technology department.

With a wealth of expertise and know-how, the Russian teams have continuously provided invaluable support to the MPE group. “Our Russian colleagues come to CERN for every year-end technical stop (YETS) and long shutdown to help us perform preventive maintenance and upgrade activities on the energy extraction systems,” says Rodríguez Mateos.

During LS2, an extensive maintenance campaign is being performed on the 13 kA systems, which already count 10 years of successful operation in the LHC. “We are currently replacing an element, the arcing contact, in each one of the 256 electromechanical switches of the energy extraction systems to ensure their continuous reliable operation throughout the next runs,” adds Rodríguez Mateos. “In February, we fully replaced 32 switches at Point 8 of the accelerator in anticipation of consolidation for the future HL-LHC.”

During LS2, the Electrical Engineering section is involved in many other activities that will be the subject of future articles.


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 23 Member States.

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

Image (mentioned), Text, Credits: CERN/Anaïs Schaeffer.


NASA Testing Method to Grow Bigger Plants in Space

ISS - Veggie Mission patch.

May 17, 2019

Image above: NASA astronaut Christina Koch initiates the Veg-PONDS-02 experiment on the International Space Station within Veggie by filling the upper reservoir on April 25, 2019. Image Credits: NASA/David Saint-Jacques.

In an effort to increase the ability to provide astronauts nutrients on long-duration missions as the agency plans to sustainably return to the Moon and move forward to Mars, the Veg-PONDS-02 experiment is currently underway aboard the International Space Station.

The present method of growing plants in space uses seed bags, referred to as pillows, that astronauts push water into with a syringe. Using this method makes it difficult to grow certain types of “pick and eat” crops beyond lettuce varieties. Crops like tomatoes use a large amount of water, and pillows don’t have enough holding capacity to support them.

As an alternative to the pillows, 12 passive orbital nutrient delivery system (PONDS) plant growth units are being put through their paces. The PONDS units are less expensive to produce, have more water holding capacity, provide a greater space for root growth and are a completely passive system—meaning PONDS can provide air and water to crops without extra power.

The 21-day experiment is a collaboration between NASA, Techshot, Inc., the Tupperware Brands Corporation, fluids experts at NASA’s Glenn Research Center and Mark Weislogel at Portland State University. As a U.S. National Laboratory, the space station provides commercial companies and government agencies with the ability to test the experiment in a microgravity environment.

“There comes a point where you have longer and longer duration missions, and you reach a cost benefit point where it makes sense to grow your own food,” said Howard Levine, chief scientist of NASA’s Utilization and Life Sciences Office at the agency’s Kennedy Space Center.

After Levine developed the PONDS prototype, it was passed on to Dave Reed, Techshot’s Florida operations director, and his team to re-engineer and make it capable of withstanding spaceflight. PONDS tested well on the ground, but when the system first arrived at the space station last year for testing in a microgravity environment, it pumped too much water to the lettuce seeds.

“We took a step back, evaluated different aspects of the design, and together with water fluid experts from NASA, we came up with three alternative designs, each of which had a number of components we wanted to test in space,” said Levine.

Image above: The Veg-PONDS-02 experiment sits in the International Space Station's two Veggie chambers. The 21-day experiment consists of 12 plant growth units in three different design configurations available for testing. Image Credits: NASA/Christina Koch.

On April 19, 2019, the Veg-PONDS-02 payload arrived at the orbiting laboratory via Northrop Grumman’s 11th Commercial Resupply mission, containing 12 PONDS units in the three new design configurations. Six of the units have a clear design to allow researchers to observe the performance of water in the units during the experiment. All units contain red romaine lettuce seeds and have been placed in the two space station vegetable production systems, known as Veggie, to test growth performance.

NASA astronaut Christina Koch initiated the experiment by filling the upper reservoir on April 25. Canadian Space Agency (CSA) astronaut David Saint-Jacques filled the PONDS unit lower reservoir on May 2 and documented how water behaved in the system.

Reed and his team worked closely with material scientists and mechanical engineers with Tupperware to design and mold components that make up the PONDS-02 units.

“We needed something that was molded well, molded precisely and molded out of plastics that were compatible with edible material,” said Reed. “They brought all this huge body of knowledge to us.”

This experiment is a way to test the performance of the three alternative design methods in space to see if the water management issue initially discovered during the first PONDS experiment has been adequately addressed.

“I look at this as a normal part of the process,” said David Brady, assistant program scientist in the International Space Station Program Science Office at NASA’s Johnson Space Center. “You find what works and what doesn’t work, and you adapt and change it. The fact that Howard and his team have been able to do that is progress.”

International Space Station (ISS). Animation Credit: NASA

On May 16, the final day of the experiment, the plants will be harvested. Six of the PONDS units will be returned to Earth on SpaceX’s 17th Commercial Resupply Services mission for further analysis. Reed’s team will take the successful components and combine them into one final PONDS design, which will pave the way for the agency to truly begin testing the growth capability of crop varieties beyond leafy greens.

“PONDS was an opportunity to do something that no one else has done before,” said Reed. “People have been growing plants in space since the Apollo era, but not like this.”

The Space Life and Physical Sciences Research and Applications Division (SLPSRA) of NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington is sponsoring the Veg-PONDS-02 investigation as part of its mission to conduct research that enables human spaceflight exploration.

Related links:



U.S. National Laboratory:

Northrop Grumman’s 11th Commercial Resupply mission:

SpaceX’s 17th Commercial Resupply Services mission:


Canadian Space Agency (CSA):

Moon to Mars:

International Space Station (ISS):

Images (mentioned), Animation (mentioned), Text, Credits: NASA/KSC/Danielle Sempsrott.


Shedding light on white dwarfs – the future of stars like our Sun

ESA - Gaia Mission patch.

17 May 2019

ESA's Gaia mission has been busy mapping our Milky Way galaxy since 2014, and just over one year ago released its second batch of data on more than one billion stars. Since then, astronomers have been exploring this catalogue to reveal a huge amount of new information about the cosmos. One type of object that has seen an abundance of new discoveries is white dwarfs.

Gaia white dwarf discoveries. Image Credits: ESA/Gaia/DPAC

White dwarfs are the remnants left behind when medium-sized stars like our Sun reach the end of their lives. These stellar relics are extremely dense, with masses comparable to the Sun's confined to volumes comparable to that of Earth; just one cubic centimetre can weigh an incredible 1000 kilograms. Finding out more about white dwarfs gives us a peek into the future, showing us what the Sun will be like in five billion years' time, once it has exhausted the fuel powering nuclear fusion reactions at its core.

White dwarfs were discovered in 1910, when astronomers observed some mysterious objects that didn't fit with the then accepted model of stellar evolution. But it took almost 50 years to find as many as one hundred of them.

Until recently, just 30 000 white dwarfs had been discovered – a tiny number compared to the few hundred billion stars that are believed to exist within the Milky Way alone. And because they radiate only a small amount of lingering thermal energy as they slowly cool down, they are very faint and so it has been difficult to uncover much about them.

Image above: A size comparison between Earth and Sirius B, the closest white dwarf. Image Credits: ESA and NASA.

Enter the Gaia era

Now, thanks to the game-changing second batch of data from Gaia, 486 641 white dwarf candidates have been detected, with 260 000 of these being high-confidence candidates, as reported in a catalogue compiled by Nicola Pietro Gentile Fusillo and collaborators. Discovering more of these mysterious objects enables us to gain better knowledge of their properties, improving our understanding of how they fit into the overall picture of stellar evolution.

"Thanks to Gaia's incredible ability to pinpoint the 3D position of huge numbers of stars, not only are we finding many more white dwarfs than we previously knew to exist, but our knowledge of their distances is hugely improving," explains Gaia scientist Stefan Jordan of Astronomisches Rechen-Institut, Zentrum für Astronomie in Heidelberg, Germany. "This allows us to decipher other properties of these stars better than we ever could in the past."

The motions of 230 000 white dwarfs

Video above: The motions of 230 000 white dwarfs. Video Credits: ESA/Gaia/DPAC.

The huge number of newly-discovered white dwarfs also means that many new classes and configurations have been revealed that didn't appear in the original 30 000. These include the first triple white dwarf system described in a paper by Marti Perpinyà-Vallès and colleagues: the triplet features three white dwarfs of the same age, which is strange if we consider that these objects are the relics of dead stars and therefore should all have formed at different times.

The Gaia catalogue includes lots of particularly cool white dwarfs, usually difficult to spot because they are so dim, as reported in studies led by Gustavo Ourique, Rodrigo González Peinado and Simon Blouin.

One of the most interesting discoveries to come out of this data release, made by Pier-Emmanuel Tremblay and collaborators, was the revelation that the cores of white dwarfs turn solid as they cool down, effectively forming extremely giant cosmic diamonds that are a million times denser than the Earth-based diamonds we are used to. This phenomenon was predicted 50 years ago by Hugh van Horn but little was understood about the process until Gaia data indicated white dwarfs release latent heat as they transform into crystals, slowing down the cooling process temporarily. The results suggest that after the Sun becomes a white dwarf in five billion years, it will take another five billion years for its core to turn solid.

Image above: Artist's impression of a solidifying white dwarf. Image Credits: Mark Garlick; University of Warwick; European Research Council.

Image above: White dwarf cooling sequence and crystallization. Image Credits: Courtesy of Pier-Emmanuel Tremblay et al. (2018).

White dwarfs inside out

The majority of white dwarfs are made up of mostly one element – typically hydrogen or helium, and in rare cases, carbon. But some have thick atmospheres, which can be polluted with heavier elements such as calcium, magnesium and iron. The new data contains information on previously-unknown polluted white dwarfs, the first of them announced in a research note by Carl Melis and collaborators; these objects are interesting because the polluting elements are thought to come from surrounding dusty disks or even unseen exoplanets or asteroids that have merged with the white dwarfs' outer layers.

Dusty disks can also lead to variability in the amount of infrared radiation that we receive from these stellar relics. One study led by Siyi Xu looked at Gaia observations of two white dwarfs that show such variability, suggesting that exoplanets could be disrupting the dusty disk.

Gaia. Animation Credit: ESA

Many new extremely low-mass white dwarfs have also been discovered in the new catalogue, as described in a paper by Ingrid Pelisoli and colleagues. The origin of these low-mass white dwarfs remains a mystery, and they don't fit with current models of stellar evolution. Finding more of them could help us better understand stars overall.

Furthermore, Gaia is enabling astronomers to study pulsating white dwarfs in greater detail. This special variety of white dwarf allows astronomers to carry out 'asteroseismology' research and study their interiors, just like seismology on Earth is used to understand the interior of our planet. Robert A. Stiller and collaborators used data from Gaia's second release to investigate the interaction between a pulsating white dwarf and its red-dwarf companion. Another study, led by Mukremin Kilic, looked for pulsations in white dwarf companions to millisecond pulsars, which are rapidly rotating, highly magnetised neutron stars – the endpoint of massive stars – and found pulsating emission from one such pair.

Near and far – white dwarfs across the Galaxy

The closest known white dwarf to Earth is Sirius B, companion of the brightest star in the night sky, Sirius A, only eight light years away. The Gaia data contained new information about Sirius A's dim companion, which were used by Simon R. G. Joyce and collaborators to improve our knowledge of the fundamental relationship between the mass and radius of white dwarfs.

Image above: An artist's impression of Sirius A and B. Image Credits: NASA, ESA and G. Bacon (STScI).

White dwarfs are also advancing our understanding of the Milky Way as a whole. Because they cool at specific rates, they are good indicators of the age of different parts of the Galaxy. Using information from Gaia on more than 150 000 of the coolest and faintest white dwarfs, Mukremin Kilic and colleagues estimated the halo of stars surrounding the Milky Way to be about 11 billion years old, helping to pin down the evolutionary history of our galaxy.

Gaia is also providing new insight into the progenitors of white dwarfs. In particular, two papers led respectively by Jeffrey D. Cummings and Kareem El-Badry used the data to investigate the relationship between the mass of a star and the mass of the white dwarf that it eventually morphs into. It is expected that future releases of Gaia data will clarify this further, helping us predict the Sun's future in greater detail.

In a different study, Ken Shen and colleagues exploited Gaia's information not only on the position and distance of stars but also on their velocities across the Milky Way to find three white dwarfs that are zipping through our Galaxy at very high speeds. One possible interpretation sees these hyper-velocity white dwarfs as the survivors of a particular type of thermonuclear explosion, known as a type-Ia supernova. These explosions happen when a white dwarf pulls matter from a stellar companion in a binary system; in this particular case, the astronomers believe that the explosion happened in a system of two white dwarfs, causing one of the two stellar remnants to disappear and throwing the other away at speeds over 1000 kilometres per second. Gaia data on the motion of one of these speedy white dwarfs even hints at the existence of a supernova remnant.

The hyper-velocity white dwarf D6-2

Video above: The hyper-velocity white dwarf D6-2. Image Credits: ESA/Gaia/DPAC.

More excitement awaits white dwarf researchers. Based on Gaia data, Peter McGill and collaborators predicted that on 11 November 2019 a nearby white dwarf will pass in front of a more distant star. The white dwarf's gravity will deflect and magnify the background star's light, acting as a gravitational lens: this unique opportunity will allow astronomers to determine the white dwarf's mass. Until and after then, scientists will keep working with existing data from Gaia and other surveys to slowly but surely unveil the many mysteries of white dwarfs.

"Since Gaia was designed with 'galactic archaeology' as its main priority, we always expected that the mission would make ground-breaking discoveries in a diverse range of areas in astronomy," concludes ESA's Gaia deputy project scientist, Jos de Bruijne. "It is extremely rewarding to witness such a large contribution to white dwarf science from this latest data release."

A huge amount remains to be discovered about white dwarfs, but with Gaia, we are deciphering these fascinating objects one step at a time.

Related links:

Dwarf catalogue:

Siyi Xu study:

Mukremin Kilic study:

ESA Gaia: and

Images (mentioned), Animation (mentioned), Videos (mentioned), Text, Credits: European Space Agency (ESA).

Best regards,

Here’s Looking at You! Astrobee’s First Robot Completes Initial Hardware Checks in Space

ISS - ASTROBEE Mission patch.

May 17, 2019

Image Credit: NASA

NASA astronaut Anne McClain performs the first series of tests of an Astrobee robot, Bumble, during a hardware checkout. To her right is the docking station that was installed in the Kibo module on the International Space Station on Feb. 15. Bumble, and another robot named Honey, launched to the space station on Apr. 17, aboard Northrop Grumman’s eleventh commercial resupply services mission from NASA’s Wallops Flight Facility in Virginia. When needed the robots will be able to return to their docking station on their own and recharge their battery power.

Animation above: Bumble, the first Astrobee robot to power up in space, blinks while connected to its docking station in the Kibo module of the International Space Station. On April 30, NASA astronaut Anne McClain unpacked Bumble and worked with Astrobee’s team at NASA’s Ames Research Center in California’s Silicon Valley to do an initial series of tests to verify that all of the robot’s subsystems — avionics, cameras, propulsion and docking for power and data transfer — were working properly before Bumble really takes flight later this spring. Animation Credit: NASA.

Astrobee is a free-flying robot system that will provide a research platform for the orbiting laboratory. The system includes three robots as well as a docking station for recharging. Robots will play a significant part in the agency’s mission to return to the Moon as well as other deep space missions. Astrobee will be used to test how robots can assist crew and perform caretaking duties on spacecraft. This will increase astronaut productivity and help maintain spacecraft when astronauts are not present near the Moon, Mars or other deep-space outposts.

Learn More:

NASA’s New Flying Robots: Bee-ing in Space for the First Time

Related links:



International Space Station (ISS):

Image (mentioned), Animation (mentioned), Text, Credits: NASA/Rick Chen.


Chang'e Fourth lander and patrol complete the fifth month of work

CLEP - China Lunar Exploration Program logo.

May 17, 2019

Chang'e 4 Lander Terrain Camera Imaging the Yutu No. 2 Patrol

The "Yutu Rabbit No. 2" patrol completed the scientific exploration work of the fifth month and entered the fifth night at 11:05 on the same day. The patrol moves according to the overall plan, and the total walking is 190.66 meters. During the movement of the patrol, the power-on detection of the payloads of the patrol infrared spectrometer, panoramic camera, neutral atomic detector, and moon-receiving radar was organized and implemented as planned, and the ground receiving load data transmission data was normal.

The No. 4 lander was completed at 12 o'clock on May 11 at the end of the night and went to sleep. During the fifth month, the lander working conditions were normal. The payload lunar neutrons and radiation dose detectors and low-frequency radio spectrometers were effectively tested as planned, and the ground receiving scientific detection data was normal.

The fourth engineering ground application system released the latest scientific test data to the research core team, with a total data volume of 6.6 GB and a total of 494 data files. In the follow-up work, the ground scientific research personnel will professionally process and analyze the obtained scientific test data.

Yutu No. 2 Patrol Camera, Panoramic Camera Imaging the No. 4 Lander

Related article:

China's Yutu-2 rover Enters Standby Mode for 'Noon Nap' as Chang'e 4 Tests Continue

Related links:

CNSA Press Release:

China National Space Administration (CNSA):

Images, Text, Credits: CNSA/CLEP/ Aerospace/Roland Berga.

Best regards,