samedi 3 juillet 2021

Salyut-5 and its phantoms

 






Soviet Space Program - Salyut Space Station patch.


July 3, 2021

Salyut-5 was launched into orbit 45 years ago. The orbital manned station "Almaz" No. 3, created at the Central Design Bureau of Mechanical Engineering (TsKBM) under the leadership of the outstanding General Designer VN Chelomey, operated under this name. At the request of the Russian Cosmos magazine of the State Corporation Roscosmos, the veterans of the enterprise shared their memories of the hard work that accompanied the flight of the “wonderful space house” (as pilot-cosmonaut Viktor Gorbatko called the station).


Start place - Baikonur

“Since this object was intended to perform a number of applied tasks in orbit, the Ministry of Defense, as the main customer, attached great importance to its creation,” recalls Vladimir Abramovich Polyachenko, chief lead designer for the Almaz system. - The first deputy commander-in-chief of the Strategic Missile Forces, Colonel-General MG Grigoriev, was entrusted to head the State Commission for flight tests of the rocket and space system, consisting of the UR-500K (Proton-K) launch vehicle, the Almaz station and the ground complex. General designer V.N. Chelomey was appointed the technical leader of the tests.

In March 1976, the preparation of the station began at the technical position of the test site. The object, located in the laboratory building at site 92, was entangled with a network of cables, pipelines, surrounded by service decks, all kinds of consoles and stands. At the entrance to the pressurized chamber, a “chamber of purity” was organized, from where one could get inside only in a light overalls, a hat, slippers and without any foreign objects.


On June 17, 1976, after three months of preparation, autonomous and complex tests, the carrier with the station was delivered to the start. The State Commission decided to launch the launch on June 22 at 21:04 Moscow time. At the appointed time, the rocket soared into the blackness of the Kazakh night like a bright torch. After entering orbit, the orbital manned station No. 3 received the public name Salyut-5. Soon "Soyuz-21" went to her: starting on July 6, a day later he delivered the first crew to watch. Boris Volynov and Vitaly Zholobov (call sign - "Baikal") started active work."

Evpatoria in touch

The Salyut-5 flight was led by the Main Operational Group, formed at the Central Command Post in Evpatoria.

“MI Lifshits (operational call sign 19, aka 'Ivanov') was appointed as the flight director, A. F. Bogdanov (19-1, aka 'Katz'), L. N. Petrov (19-1 , aka "Katsman") and A. Ya. Petrunko (19-1, aka "Katsnelson"), - recalls the shift leader of the "Salyut-5" flight Alexei Yakovlevich Petrunko. - These callsigns and second surnames were assigned to us in the framework of countering foreign technical intelligence. We used them for open voice communication with the crew and for signing open telegrams on board.


The work went on around the clock, in three shifts ... All the parameters of the station's systems were within the specified limits, and after the transition from Soyuz-21 to Salyut-5, the crew highly appreciated the comfort in its compartments. From that moment on, Boris Volynov and Vitaly Zholobov began to carry out the flight program.

When, on the 46th day, due to an error in the daily program, Salyut-5 lost its orientation, the necessary commands left over the radio link to ensure the viability of the crew and the station as a whole. The cosmonauts received recommendations for restoring orientation and bringing the life support system into working position. In complete silence, everyone was looking forward to the next communication session. Telemetry appears earlier - and we were very happy to see that Almaz-5 is in the normal orientation."

Overcoming difficulties

On subsequent orbits, the commander and flight engineer suddenly reported some foreign odors. Neither the activation of the air purification system, nor the change in the operating modes of the life support systems changed anything. The doctors' recommendations did not help, and on August 22, a report was received about the deterioration of Vitaly Zholobov's health. The next day, the flight engineer could no longer work. We decided to terminate the flight ahead of schedule.


“On August 24, 1976, the Soyuz-21 crew returned to Earth,” recalls V. A. Polyachenko. - On September 23, at a meeting of the State Commission, Boris Volynov said: “Currently we feel good. The orbital station is mothballed and prepared to receive the second crew. Salyut-5 is a magnificent complex that should live, and we are convinced of the need for a second expedition."

On October 14, 1976, the Rodonov crew consisting of Vyacheslav Zudov and Valery Rozhdestvensky left for the station on Soyuz-23. However, the docking of the spacecraft with the Salyut-5 scheduled for the next day did not take place due to large fluctuations in the signal of the radio-technical rendezvous system. The mooring and attitude control engines of the ship operated in the self-oscillation mode, the lateral deviations relative to the station increased. The docking program was turned off, and the astronauts were returned to Earth.


On October 16, the Soyuz-23 descent vehicle splashed down into Lake Tengiz. By coincidence, 20 years before the events described, this section of the Akmola region of Kazakhstan was assigned to the area of ​​the fall of the first stages of the R-7 ballistic missile during launches from Baikonur. Unfriendly place: cold, snowstorm, the surface of the lake is covered with a layer of sludge - a mixture of ice, snow and water. There is nothing to get the descent vehicle with the freezing crew ... And finally luck: having hooked the Soyuz-23 with a rope, the helicopter towed it to the shore. The astronauts are alive and well.

On October 26, the heroes were met by Star City. VN Chelomey at the solemn meeting thanked them for their courage and joked: "Fate does the right thing with people: they got into the water, into the bitter-salty water, and one of them is a sailor." Valery Rozhdestvensky was a military sailor-diver before the cosmonaut corps.

What was it?

“The story with unpleasant odors on board Salyut-5 showed that in space flight, non-observance of the work and rest regime has a huge impact on the psychophysical state of a person,” said Boris Izrailovich Kushner, head of the air conditioning department. - From the 10th day of the flight, Boris Volynov and Vitaly Zholobov began to receive complaints about some foreign odors in the atmosphere of the pressurized compartment. After the consultation of doctors, it was decided to interrupt the further flight: instead of 60, it lasted 49 days."

The special commission headed by the director of the Institute of Biomedical Problems, Oleg Georgievich Gazenko, included chief designers and prominent specialists in life support systems, doctors, toxic chemists, material developers, and psychologists. The commission concluded that the smell felt by the astronauts was "phantom", that is, it was born directly in the corresponding parts of the brain. It was the result of the inept actions of the ground services, who planned the daily work programs of the cosmonauts.


Based on the results of this flight, an instruction was developed that categorically forbade the astronauts to sleep and rest, and the planned duration of the work should not exceed 4–5 hours a day.

We developed special security measures: astronauts with special hand-held alarms (for all possible harmful impurities) had to enter the station wearing gas masks and measure the gas composition of the atmosphere. If at least one parameter was found to exceed the permissible concentration, the crew would return to Earth.

On February 7, 1977, the Tereki, cosmonauts Viktor Gorbatko and Yuri Glazkov, set off for the station on the Soyuz-24. The docking went brilliantly. In Evpatoria, the opening of the hatches with great excitement was awaited by the best doctors, chemists-toxicologists, specialists in life support systems, cosmonauts, and at TsKBM - the main developers of the station, headed by V.N. Chelomey.

Finally, the voice of Viktor Gorbatko was heard over the speakerphone: "Everything is fine here, you enter like a good big house!" According to the conditional code, this meant that there were no smells in the station. Measurement of the composition of the atmosphere did not reveal any impurities. The station's reputation was completely restored.


The cosmonauts stayed on board Salyut-5 for the planned 18 days, successfully completed all the tasks assigned to them, and returned to Earth on February 25. On March 30, a large meeting of the TsKBM team with the crews that visited the station took place. It was especially noted that "Gorbatko and Glazkov brought complete clarity to all technical problems, closed all misunderstandings." Having completed 6630 revolutions around the Earth, on August 8, 1977 Salyut-5 completed its 412-day flight.

Preparation and more preparation

“Without any doubt, we can say that great attention was paid to the training of the Almaz crews,” says Leonard Dmitrievich Smirichevsky, a space technology tester. - The cosmonauts were taught at various stands, at the analogue of the station, in the thematic departments. They trained on a complex simulator, studied onboard documentation, including instructions for the crew's actions in emergency situations. Documentation played an important role in the flights on the Salyut-5.


On March 30, 1977, at the meeting of the crews with the developers, many good words were spoken about the cosmonauts. I remember the moment when Yuri Glazkov presented VN Chelomey with a stopwatch and an on-board control and operation manual in response to the coinage with the station image on the background of the Earth, handed over to all crews. They were placed in one of the showcases of the Museum of History and Achievements of the enterprise. The same exposition contains envelopes and stamps with autographs of astronauts, canceled on board the station. These unique exhibits are of great interest to museum visitors. Many years later, we recall with satisfaction that tense, but interesting and friendly work, the fruits of which are still in demand today - in the development of modern spacecraft."

Russian space, Vladimir Leonardov.

ROSCOSMOS Press Release: https://www.roscosmos.ru/31747/

Images, Credits: ROSCOSMOS/Original Text in Russian mentioned, translation: Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

CASC - Long March-2D launches five satellites

 







CASC - China Aerospace Science and Technology Corporation logo.


July 3, 2021

Long March-2D launch

A Long March-2D launch vehicle launched five satellites from the Taiyuan Satellite Launch Center, Shanxi Province, northern China, on 3 July 2021, at 02:51 UTC (10:51 local time).

Long March-2D launches five satellites

Jilin-1 Kuanfu-01B (吉林一号 宽幅01B), also known as “Inner Mongolia One” (内蒙古一号), is an Earth-observation satellite with “high resolution, super wide range, super large storage, and high-speed data transmission”, according to the manufacturer.

Jilin-1 Gaofen-03D satellite

Jilin-1 Gaofen-03D-01 (高分03D01), Gaofen-03D-02 (高分03D02) and Gaofen-03D-03 (高分03D03) will join the previous Gaofen-03 launched to “provide users in forestry, agriculture, grassland, ocean, resources, environment and other industries with richer remote sensing data and product services”. The fifth satellite launched was Xingshidai-10 (星时代-10), a low-cost satellite.  According to official sources, all five satellites entered the scheduled orbits and the launch mission was declared a complete success.

For more information about China Aerospace Science and Technology Corporation (CASC): http://english.spacechina.com/n16421/index.html

Images, Video, Text, Credits: China Central Television (CCTV)/Chang Guang Satellite Technology Co., Ltd/ China Aerospace Science and Technology Corporation(CASC)/SciNews/Günter's Space Page/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

vendredi 2 juillet 2021

Space Station Science Highlights: Week of June 28, 2021

 







ISS - Expedition 65 Mission patch.


Jul 2, 2021

Scientific investigations conducted the week of June 28 aboard the International Space Station included studies on characterization of microbial pathogens, magnetic assembly of colloid structures, and plant gene expression. A Northrop Grumman Cygnus supply craft departed the station on June 29 after a four-month mission, and a SpaceX Dragon is scheduled to leave on July 6.


Image above: The space station transits the Sun at roughly five miles per second on Friday, June 25, 2021, from near Nellysford, Va., with NASA astronaut Shane Kimbrough and ESA astronaut Thomas Pesquet working outside to install the second ISS Roll-Out Solar Array (iROSA) on the 4B power channel. Image Credits: NASA/Joel Kowsky.

The space station has been continuously inhabited by humans for 20 years, supporting many scientific breakthroughs. The orbiting lab provides a platform for long-duration research in microgravity and for learning to live and work in space, experience that supports Artemis, NASA’s program to go forward to the Moon and on to Mars.


Image above: The Cygnus space freighter is pictured in the grip of Canadarm2 moments before its release after completing a four-month cargo mission at the International Space Station. Image Credit: NASA.

Here are details on some of the microgravity investigations currently taking place:

Monitoring microbes

Microbial Tracking-3 continues a series of studies monitoring the ability of certain bacteria and fungi to cause disease (or act as pathogens) and their resistance to antibiotics, and analyzing gene expression. The effects of spaceflight on viral and microbial pathogen dynamics are largely unknown, and results could support efforts by the NASA GeneLab to characterize such microbes and predict which ones may pose a threat to crew health. Bacteria and fungi have shown remarkable ability to adapt to different environments, including human-made places such as homes and offices and closed habitats such as the space station. Microbes associated with built environments typically originate from human occupants and often adapt to living on or in the human body. Following a conference with the researchers, crew members performed surface sample collections during the week.

Magnetic colloid materials


Image above: NASA astronaut Shane Kimbrough sets up for InSPACE-4, a physics study exploring advanced materials and manufacturing techniques. Image Credit: NASA.

InSPACE-4 studies using magnetic fields to assemble tiny structures from colloids, or particles suspended in a liquid. Colloidal structures give the assembled material unique properties, such as how the material responds to or interacts with light and heat. Microgravity makes it possible to observe colloid assembly in ways and over time scales not possible on Earth. Results could lead to more advanced materials for space applications, including thermal shields, micrometeorite protection, energy production, and actuators and sensors for robotic and human missions. This work also may advance the manufacturing of materials on Earth for applications such as thermal shields, sound damping devices, camouflage, medical diagnostics, and possibly even active cloaking materials, as well as larger-scale applications, including building foundation stabilizers in areas prone to earthquakes. During the week, crew members installed hardware, resolved a camera issue, and conducted experiment runs.

Examining plant gene expression


Image above: NASA astronaut Megan McArthur works on the APEX-07 investigation, which examines how spaceflight affects gene expression in roots and shoots to help facilitate the adaptation of plants to space. Image Credit: NASA.

APEX-07 examines how spaceflight affects plants at the level of gene expression. Previous research shows that microgravity plays a role in which plant genes turn on or off, which proteins are present and in what amounts, and the modifications made to those proteins. All these processes are controlled by RNA, and the study analyzes the role of RNA regulation on gene expression during spaceflight in both roots and shoots of plants. Future long-duration spaceflights and missions likely will use plants as a source of food, to replenish water and purify air, and for physiological and psychological benefits to crew members. This research helps facilitate the adaptation of plants to space and extreme environments on Earth. Following a final harvest of the plants, crew members cleaned and dried hardware and deactivated the experiment.

Other investigations on which the crew performed work:

- DREAMS, an ESA (European Space Agency) investigation, demonstrates a wearable headband used to monitor astronaut sleep quality. Poor sleep quality can affect astronaut health and mission performance.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8344

- Phospho-aging, an investigation from the Japan Aerospace Exploration Agency (JAXA), examines the molecular mechanisms behind aging-like symptoms such as bone and muscle loss in space. Results could lead to better countermeasures and treatments to protect crews on future missions and to help people on Earth as well.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8278

- RTPCG-2 demonstrates new methods for producing high-quality protein crystals in microgravity for analysis on Earth, which could help identify possible targets for drugs to treat several diseases.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8073

- Oral Biofilms in Space studies how gravity affects the structure, composition, and activity of oral bacteria in the presence of common oral care agents. Findings could support development of novel treatments to fight oral diseases such as cavities, gingivitis, and periodontitis.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8160

- Food Acceptability looks at how the appeal of food changes during long-duration missions. Whether crew members like and actually eat foods directly affects caloric intake and associated nutritional benefits.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7562

- Antimicrobial Coatings tests a coating to control microbial growth on different materials that represent high-touch surfaces on the space station. Some microbes change characteristics in microgravity, potentially creating new risks to crew health and spacecraft.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8352

- Standard Measures collects a set of core measurements from astronauts before, during, and after long-duration missions to create a data repository to monitor and interpret how humans adapt to living in space.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7711

- ISS Ham Radio provides students, teachers, parents, and others the opportunity to communicate with astronauts using ham radio units. Before a scheduled call, students learn about the station, radio waves, and other topics, and prepare a list of questions on topics they have researched.
https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=337

Space to Ground: At the Midpoint: 07/02/2021

Related links:

Expedition 65: https://www.nasa.gov/mission_pages/station/expeditions/expedition65/index.html

Microbial Tracking-3: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8333

InSPACE-4: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7669

APEX-07: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8299

ISS National Lab: https://www.issnationallab.org/

Spot the Station: https://spotthestation.nasa.gov/

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

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

Images (mentioned), Video (NASA), Text, Credits: NASA/Ana Guzman/John Love, ISS Research Planning Integration Scientist Expedition 65.

Greetings, Orbiter.ch

From antimatter to heavy isotopes, data-taking in physics facilities is resuming at CERN

 







CERN - European Organization for Nuclear Research logo.


July 2, 2021

With the Proton Synchrotron and its Booster accelerating protons to high energies again, the physics season can start at the ISOLDE radioactive ion beam facility and the Antimatter Factory


Image above: The ISOLDE's facility many transfer lines transport radioactive isotopes to experimental stations where their characteristics are examined (Image: CERN).

As the two-year-long shutdown of CERN’s accelerators comes to an end, some of the Laboratory’s many experiments are not waiting for the Large Hadron Collider (LHC) to wake up before starting to take data. The Proton Synchrotron (PS), CERN’s 60-year-old particle accelerator, and its injector, the Proton Synchrotron Booster, are back in full roar after a major overhaul. The Booster has begun delivering protons accelerated to 1,4 GeV to the ISOLDE facility (Isotope mass Separator On-Line Detector) and 2 GeV protons to the Proton Synchrotron, which, in turn, feeds its 26 GeV proton beam to the Antiproton Decelerator (AD, the first of the two particle decelerators of the Antimatter Factory). For the many experiments housed in these two world-class facilities, this can only mean one thing – the physics season is about to start, bringing with it the promise of exciting new results in nuclear and antimatter research.

“After optimising the experiment when the first proton beam reached the ISOLDE facility’s target on 21 June, physics data-taking started swiftly and the first experiment finished successfully after five days,” explains Gerda Neyens, Physics Group Leader at the ISOLDE facility. At ISOLDE, collisions between the Booster proton beam and heavy targets produce rare radioactive isotopes of elements from across the periodic table, of which specific ones are selected using a combination of lasers and electric and magnetic fields. This season’s first ISOLDE results came from the CRIS experiment in the form of hyperfine spectra of a series of silver isotopes synthesised within the walls of the facility. The atomic spectra of more than 20 exotic short-lived silver isotopes will reveal how the internal quantum structure, size and shape of the stable 107Ag and 109Ag isotopes change when neutrons are added to or removed from them.

For the upcoming physics season, ISOLDE will relies on new target stations to produce the radioisotopes, as well as an upgraded charge breeder (a device that removes electrons from the heavy isotopes) and a refurbished superconducting linear accelerator to accelerate the produced radioisotopes. The nuclear reactions occurring in the facility, which mimic and help understand those taking place inside stars, can thus be studied with greater precision.

Situated a few dozen metres away from ISOLDE, the Antimatter Factory uses the Proton Synchrotron beams to create its own peculiar substance. This process resumed on 28 June with the return of the beam on the new target: antimatter is being made at CERN again as you read. In this unique factory, antiprotons are synthesised by colliding the proton beams onto a target. The stray particles are then focused back into a beam thanks to a device called a “magnetic horn”, which was completely renovated in recent years, as was the target itself. The new target is an air-cooled piece of iridium placed in a graphite matrix and enclosed in a titanium alloy double shell. It will improve antiproton production, for a reliable and stable antimatter inflow over time.

The data-taking period that now awaits antimatter physicists has been given a boost by new machines such as ELENA (Extra Low Energy Antiproton deceleration ring), a ring that efficiently decelerates the antiprotons to unprecedented levels before feeding them into the experimental area. There, long-standing collaborations like AEGIS, ASACUSA and ALPHA stand next to fresh faces like ALPHA-G and GBAR, an experiment aiming to measure the freefall acceleration of antimatter under gravity. They will soon be joined by the PUMA and BASE-STEP collaborations, which were recently approved by the CERN Research Board. Both of these experiments will rely on the delicate process of transporting antimatter to neighbouring areas of the CERN site to study its properties.

Diversity is a defining characteristic of CERN, and this applies to the Organization’s research programme too. So, although the LHC and its detectors will not start buzzing and whirring for a few more months, there is no shortage of interesting developments: with antimatter and nuclear isotope data-taking and the forthcoming start of the physics season in the East and North experimental areas as well as at n_TOF, the next few months will be hectic ones for physics research.

360 tour in the renovated AD target area!

Video above: A 360° virtual tour through the AD target area at CERN - use the arrows to change your perspective. Video Credit: CERN.

Note:

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

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.

Related links:

Large Hadron Collider (LHC): https://home.cern/science/accelerators/large-hadron-collider

Proton Synchrotron (PS): https://home.cern/science/accelerators/proton-synchrotron

Proton Synchrotron Booster (PSB): https://home.cern/science/accelerators/proton-synchrotron-booster

ISOLDE facility’s: https://home.cern/science/experiments/isolde

CRIS experiment: https://isolde.cern/cris

ELENA (Extra Low Energy Antiproton deceleration ring): https://espace.cern.ch/elena-project/SitePages/Home.aspx

AEGIS: https://home.cern/science/experiments/aegis

ASACUSA: https://home.cern/science/experiments/asacusa

ALPHA: https://home.cern/science/experiments/alpha

ALPHA-G: https://home.cern/news/news/experiments/new-antimatter-gravity-experiments-begin-cern

GBAR: https://home.cern/science/experiments/gbar

PUMA and BASE-STEP collaborations: https://home.cern/news/news/physics/cern-approves-two-new-experiments-transport-antimatter

For more information about European Organization for Nuclear Research (CERN), Visit: https://home.cern/

Image (mentioned), Video (mentioned), Text, Credits: CERN/By Thomas Hortala.

Best regards, Orbiter.ch

NASA Rocket, Satellite Tag-Team to View the Giant Electric Current in the Sky

 






NASA - Ionospheric Connection Explorer (ICON) logo.


Jul 2, 2021

Some 50 miles up, where Earth’s atmosphere blends into space, the air itself hums with an electric current. Scientists call it the atmospheric dynamo, an Earth-sized electric generator. It’s taken hundreds of years for scientists to lay the groundwork to understand it, but the principles that keep it running are only just now being revealed in detail.

Following up on its predecessor’s 2013 flight, the Dynamos, Winds, and Electric Fields in the Daytime Lower Ionosphere-2, or Dynamo-2, sounding rocket mission will soon pierce the atmospheric winds thought to keep the dynamo churning. With the sounding rocket’s launch timed as NASA’s Ionospheric Connection Explorer satellite passes nearby, these two space missions will combine their perspectives to advance our understanding of the giant electric circuit in the sky. See below for information on how to stream the launch and where it will be visible in person.

The Dynamo mission

The atmospheric dynamo is a pattern of electrical current swirling in continent-sized circuits high above our heads. Driven by the Sun, it migrates across the planet, centered wherever the Sun is directly overhead. It comes alive in Earth’s ionosphere, a layer of the atmosphere where the Sun’s intense radiation separates electrons from their atoms, allowing electricity to flow.


Image above: A map of the ionospheric currents at the time of Dynamo 1’s launch on July 4, 2013. Currents – whose intensity is marked by red and blue coloring – travel in opposite directions on either side of the magnetic equator, marked with a pink line. The yellow dots are magnetometer readings from the ground. Graphic Credits: NASA/JAXA/R. Pfaff et al.

Most measurements of the dynamo come from magnetometers on the ground, which monitor how that current disturbs Earth’s magnetic field (think of them as souped-up compasses). Ground-based measurements have their advantages – they can monitor one location for long periods of time, for instance. But to really see what’s going on in detail, you have to make measurements from inside the ionosphere, right where the electric current flows.

“It’s a really tricky part of space to get measurements, because the air is much too thin for an aircraft, and yet it's still too dense to fly most spacecraft,” said Scott England, space physicist at Virginia Tech in Blacksburg and collaborator for the upcoming Dynamo-2 campaign. “So one way of making these measurements is to fly a rocket through it.”

Sounding rockets, named for the nautical term “to sound,” meaning to measure, launch to make brief measurements in space before falling back to Earth a few minutes later. They excel at reaching hard-to-access regions of space that are too low for satellites to measure and too high to reach with scientific balloons – and they’re ideal for comparing wind speeds at different altitudes, since they slice through the atmosphere near-vertically.

“While ground-based methods can provide large-scale, integrated measurements, sounding rockets give us local, fine-scale data on the ionospheric current,” said Takumi Abe, space physicist at the Japan Aerospace Exploration Agency, or JAXA, and collaborator for the Dynamo missions. “That's when we use sounding rockets – when we'd like to see the small-scale physics.”

The first Dynamo mission – comprising scientists from NASA, JAXA, and several U.S. universities – launched their rockets on the 4th of July, 2013, from NASA’s Wallops Flight Facility on Wallops Island, Virginia. The team divided their instruments between two rockets, the first measuring electric fields while the second, launched just 15 seconds later, traced the winds, leaving behind a cloudy plume that glistened red in the sunlight similar to those observed in firework shows.

Observing from the ground and from a NASA aircraft, the team watched the crimson clouds morph in the wind as simultaneous electric field measurements were beamed back to the ground.


Image above: A picture of the rocket plumes shortly after the launch of both Dynamo rockets from Wallops Flight Facility on July 4, 2013. Image Credits: NASA/JAXA/R. Pfaff et al/Ken Kramer.

The vapor trail teased about in the wind, twisting and curling into a spiraling zig-zag. The telltale shape meant the winds were changing direction along the rocket’s flight path.

“They moved first to the east, and then a few miles above, they're all moving to the west, and a few miles above, they're all moving back to the east,” England said.

The zig-zag confirmed one aspect of the theory of atmospheric tides, which create high-altitude winds thought to drive the atmospheric dynamo. Heat from the ground below radiates up in waves, forcing parts of the atmosphere to move back and forth like the ebb and flow of ocean waves as they hit the beach.

“The zig-zag is the signature of this huge wave moving through this region,” England added.

Though the winds were expected by theory, their strength was not.

Based on magnetometer readings from the ground at the time, the team expected a weak current and mild winds above. Indeed, things were calm below the ionosphere’s base. But right where the reddish cloud trail pierced the lower parts of the ionosphere, where the dynamo is strongest, it was rapidly smeared across the sky.

“Just in the dynamo region, the wind suddenly takes off and gets very fast, over 150 meters per second (335 miles per hour),” said Rob Pfaff, space physicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and principal investigator for both Dynamo missions. “It’s much stronger than what's predicted.”

These oppositely directed, high-speed winds were too fine-grained to be detected from ground-based measurements.

“It might look from the ground like the wind is going east at a very low speed,” said England. “But it turns out that's a very high speed to the east and a slightly lower speed to the west, averaged together.”

A satellite and rocket tag-team

Though the 2013 observations from the Dynamo rockets were surprising, they jibe with newer measurements from NASA’s Ionospheric Connection Explorer, or ICON, satellite.

ICON, a satellite mission launched in October 2019, flies at an altitude of about 360 miles, looking down on the same ionospheric winds that Dynamo rockets measured from within. Lately, ICON had also observed much faster winds than expected by theory, and the team didn’t know what to make of them.

“Having the verification by these rocket results that what we're seeing with ICON is real – it's even sharper than what we can see,” said England, who is the project scientist for the ICON mission.

ICON’s wind measurements aren’t as high resolution as the Dynamo rockets’ were, but it can see much broader swaths of space, and can repeat those observations on each orbit. The Dynamo-2 mission campaign will combine their strengths.

“We are going to time it so that ICON is flying past around the same time that rocket is launching,” England said. “That way we can really combine all the amazing strengths in the data that's highlighted in this paper with the larger picture view from ICON.”


Image above: Illustration of NASA’s Ionospheric Connection Explorer, or ICON. ICON explores Earth’s upper atmosphere and ionosphere, a region influenced by both terrestrial weather and changes in near-Earth space. Image Credits: NASA's Goddard Space Flight Center Conceptual Image Lab.

The first Dynamo rockets launched together around noon, when the current was flowing from east to west. This time, the Dynamo-2 rockets will likely launch at different times, in the morning and afternoon, to capture the current when it is flowing in different directions.

“We're going to take measurements in the morning and in the afternoon to complete the circle, so to speak, and see how all this comes together in one big picture,” Pfaff said.

However, Pfaff may instead launch one rocket during geomagnetically “quiet” times and one during “disturbed” times, when the ionosphere’s activity is especially complex, which would provide equally valuable insight. Which plan they follow will depend on how solar activity and the dynamo currents themselves are looking in real time once the launch window opens.

The Dynamo-2 rockets will also use a novel instrument developed by co-investigator Jim Clemmons at the University of New Hampshire in Durham. The instrument measures winds by monitoring pressure gradients in the air around the rockets instead of releasing clouds that must be tracked from the ground or sky.

“And the beauty of that is we don't have to rely on clear skies and we don't have to get an airplane in the air – we can just do it,” Pfaff said.

Pfaff hopes the new results will help the team understand what’s driving the unduly fast winds, and what the consequences are for understanding the atmospheric dynamo.

Discovering the dynamo in the sky

The atmospheric dynamo is so named because it operates with the same principles as the electric dynamo, a kind of electric generator. The first dynamo was not found in nature but rather constructed in a lab.

In the early 1800s, on the cusp of the Victorian era in Britain, fascination with electricity was reaching a fever pitch as reports of fundamental discoveries arrived from across Europe. The invention of the battery, the discovery of electrical current, and several puzzling effects relating electricity to magnetism were related on a nearly monthly basis.

Michael Faraday – a bookbinder’s apprentice turned self-taught experimentalist – was toiling in his London lab, working on a strange new device that, though he didn’t know it, would eventually change the world.

Faraday’s sketch of his first dynamo machine. Drawing Credits: © The Royal Society

It consisted of a copper disc, mounted like a bicycle wheel so as to spin between two magnets. He connected the disc to an instrument that measured electric current, invented just 10 years earlier.

Faraday rotated the disc and the needle on his instrument wiggled – a small electric current was beginning to flow. Historians would later identify this moment – October 28, 1831, according to his diary – as the first time humans turned motion into electricity. Faraday had discovered electrical induction, and as a bonus, built the first dynamo, or electric generator. It was the prototype of a technology that today keeps our lights on, our computers running, and the entire modern economy afloat.

What made Faraday’s device work were three key ingredients: a magnetic field (created by the two magnets), a conductor (the copper disc), and motion. Combining those three, he had discovered that moving a conductive material within a stationary magnetic field – or moving a magnetic field around a stationary conductor – will start an electric current flowing.

Eventually, scientists discovered each of those three ingredients operating on Earth at a much larger scale.

The atmospheric dynamo, one piece at a time

Of the three components of the atmospheric dynamo – a magnetic field, a conductor, and motion – Earth’s magnetic field was discovered first.

By the early 1100s, Chinese seafarers were already using magnetic compasses to navigate on cloudy, starless nights, though the reason for their reliable alignment wasn’t known. William Gilbert’s De Magnete, published in London in 1600, was the first to explain this behavior with the idea that the Earth itself was a giant magnet.

Astronomers began mapping Earth’s magnetic field, and by 1701, English astronomer Edmond Halley, charting the Atlantic with his compass, produced the first map of Earth’s magnetic field.


Image above: First map of Earth’s magnetic field based on compass readings, by Edmond Halley, after sailing the Atlantic Ocean on the Paramore. Since we now know Earth’s magnetic pole shifts over time, these lines are not stable – scientists update the World Magnetic Model every five years. As of 2019, the magnetic north is moving towards Siberia at a rate of about 34 miles (55 km) per year. Image Credits: E. Halley/Princeton Library Historic Maps Collection.

As compasses gained wider use for scientific purposes, some observers noticed an irregularity: compass readings seemed to flicker on a daily schedule.

“Ever since the 19th century, people would observe, particularly near noon, this little wiggle on these really big compasses,” said Pfaff.

The wiggling compass needles fit well with new findings on the relationship between electricity and magnetism. In 1820, Danish scientist Hans Christian Ørsted had observed that running an electric current through a conductive wire deflected the needle of a nearby compass, effectively “wiggling” the magnetic field it sensed. Faraday’s dynamo machine, constructed 11 years later, showed how a wiggling magnetic field could induce a current. Magnetic fields, motion, and electricity – the three went together. If that was right, then the wiggling compass needles on Earth might mean that somehow, an electric current was running overhead. But where that current was coming from, and the conductor it was traveling through, was far from clear.

In 1882, English scientist Balfour Stewart penned an Encyclopedia Brittanica entry that correctly identified the source, though it was conjecture at the time. A part of the upper atmosphere itself, he wrote, might be conductive – the air above us could become electrified.

That conductive part of the atmosphere was eventually discovered through practical experience. As World War I created a need for long-distance radio communication, experimenters discovered that radio signals could travel between continents – around the curvature of the Earth – by somehow bouncing off of the sky. The only viable explanation for their success was a reflective – that is, conductive – layer of the atmosphere.


Figure above: Figure 1 from Appleton’s Nobel Prize lecture in 1947, demonstrating how a radio wave can travel long distances by reflecting off an ionized layer of the atmosphere. Figure Credits: ©The Nobel Foundation.

In 1927, English physicist Edward Appleton studied those radio signals to confirm that there was indeed an electrically conductive layer of the atmosphere. (He called it the “E-layer,” for “electrically conductive”.) Over the following decades, several more sublayers of what became known as the ionosphere – where Earth’s atmosphere contains substantial populations of charged particles, ions and electrons – would be discovered and characterized. The second component of Earth’s atmospheric dynamo, the conductive ionosphere, had been found.

Still, the current didn’t seem to be flowing constantly. The wiggling compass needles only twitched occasionally, most strongly at noon. Something must be moving the ionosphere strongest when the Sun was right overhead.

The discovery of the final component of the atmospheric dynamo, the source of motion, would have to wait for the space age, when rockets, balloons, and early satellites could measure atmospheric winds. In 1970, systematizing two decades of data, space physicists Sydney Chapman and Richard Lindzen developed the theory of atmospheric tides, the key to the ionosphere’s pulsing currents.

The idea was that as the Sun beats down on Earth, its heat radiates back upwards. In response, the entire atmosphere expands. A high-flying observer would experience this expansion as strong gusts of wind.

When those winds reach the base of the ionosphere, where the Sun’s radiation separates neutral particles into electrically charged ions and electrons, they push them along too. As a result, the ionosphere – a conductor – moves against Earth’s magnetic field, swishing to and fro with the wind.

“With these key ingredients together, the force of the wind pushing on those ions and electrons in the presence of Earth's magnetic field, we can get a current flowing in the Earth's upper atmosphere,” said England. “That's what we call the dynamo.”

“We’ve come a long way since Faraday’s time,” Pfaff said. “After two centuries of research, it is exciting to journey into space and observe dynamos that are part of our natural environment.”

The Dynamo-2 rockets will launch from NASA’s Wallops Flight Facility on Wallops Island, Virginia between July 6-20. The two rockets will not be launched on the same day. The launch window on July 6 runs from 12:15 p.m. to 2 p.m. EDT. On July 7-13, the launch window runs from 10 a.m. to 2 p.m. EDT and from 8 a.m. to noon EDT on July 14-20. Live coverage of the launches will begin 20 minutes before the opening of the launch window on the Wallops YouTube site. The NASA Visitor Center at Wallops will not be open for this mission. The launches may be visible in the mid-Atlantic region.

Related links:

ICON (Ionospheric Connection Explorer): http://www.nasa.gov/icon

Sounding Rockets: http://www.nasa.gov/mission_pages/sounding-rockets/index.html

Images (mentioned), Drawing (mentioned), Graphics (mentioned), Text, Credits: NASA’s Goddard Space Flight Center, by Miles Hatfield.

Greetings, Orbiter.ch

Operations Underway to Restore Payload Computer on Hubble Space Telescope

 






NASA - Hubble Space Telescope patch.


July 2, 2021

June 30, 2021 - NASA Preparing for Procedures to Turn On Backup Hardware on the Hubble Space Telescope

NASA is taking additional steps to investigate the Hubble Space Telescope’s payload computer issue that began on June 13, suspending science observations. In parallel with the investigation, NASA is preparing and testing procedures to turn on backup hardware onboard the spacecraft.  The telescope itself and science instruments remain healthy and in a safe configuration.

The source of the computer problem lies in the Science Instrument Command and Data Handling (SI C&DH) unit, where the payload computer resides. A few hardware pieces on the SI C&DH could be the culprit(s).

Hubble Space Telescope (HST). Image Credit: NASA

The team is currently scrutinizing the Command Unit/Science Data Formatter (CU/SDF), which sends and formats commands and data. They are also looking at a power regulator within the Power Control Unit, which is designed to ensure a steady voltage supply to the payload computer’s hardware. If one of these systems is determined to be the likely cause, the team must complete a more complicated operations procedure to switch to the backup units. This procedure would be more complex and riskier than those the team executed last week, which involved switching to the backup payload computer hardware and memory modules. To switch to the backup CU/SDF or power regulator, several other hardware boxes on the spacecraft must also be switched due to the way they are connected to the SI C&DH unit.

Over the next week or so, the team will review and update all of the operations procedures, commands and other related items necessary to perform the switch to backup hardware. They will then test their execution against a high-fidelity simulator.

The team performed a similar switch in 2008, which allowed Hubble to continue normal science operations after a CU/SDF module failed. A servicing mission in 2009 then replaced the entire SI C&DH unit, including the faulty CU/SDF module, with the SI C&DH unit currently in use.

Since that servicing mission, Hubble has taken over 600,000 additional observations to exceed 1.5 million during its lifetime.  Those observations continue to change our understanding of the universe.

Launched in 1990, Hubble has been observing the universe for over 31 years. It has contributed to some of the most significant discoveries of our cosmos, including the accelerating expansion of the universe, the evolution of galaxies over time, and the first atmospheric studies of planets beyond our solar system. Read more about some of Hubble’s greatest scientific discoveries.

Related articles:

NASA Completes Additional Tests to Diagnose Computer Problem on Hubble Space Telescope
https://orbiterchspacenews.blogspot.com/2021/06/nasa-completes-additional-tests-to.html

Operations Underway to Restore Payload Computer on NASA's Hubble Space Telescope
https://orbiterchspacenews.blogspot.com/2021/06/operations-underway-to-restore-payload.html

Related link:

Hubble Space Telescope (HST): https://www.nasa.gov/mission_pages/hubble/main/index.html

Image (mentioned), Text, Credits: NASA/Lynn Jenner/Elizabeth Landau/GSFC/Rob Gutro/Claire Andreoli.

Best regards, Orbiter.ch

From atoms to planets, the longest-running Space Station experiment

 







ISS - International Space Station logo.


July 2, 2021

PK-4 parts

As Europe celebrates 20 years of ESA astronauts on the International Space Station, a Russian-European experiment has been running quietly in the weightless research centre for just as long: the Plasma Kristall (PK) suite of investigations into fundamental science.

Oleg working on PK-4

Plasma Kristall takes a plasma and injects fine dust particles in weightlessness, turning the dust into highly charged particles that interact with each other, bouncing off each other as their charge causes the particles to attract or repel. Under the right conditions, the dust particles can arrange themselves over time to form organised structures, or plasma crystals.

These interactions and forming of three-dimensional structures resemble the workings of our world on the atomic scale, a world so small that we cannot see move even with an electron microscope. Add a laser to the mix and the dust particles can be seen and recorded for observation by scientists on Earth for a sneak peak of the world beyond our eyes.

Visualising the laws of physics

These surrogate atoms are a way for researchers to simulate how materials form on an atomic scale, and to test and visualise theories. The experiment cannot be run on Earth because gravity only makes sagging, flattened recreations possible; if you want to see how a crystal is constituted you need to remove the force pulling downwards – gravity.

Sergei Krikalev with the PKE-Nefedov experiment during Expedition 1 mission

On 3 March 2001, “PK-3 Plus” was turned on in the Zvezda module, the first physical experiment to run on the Space Station. Led by the German aerospace centre DLR and Russian space agency Roscosmos the experiment was a success and later followed up by a fourth version, installed in 2014 in ESA’s Columbus laboratory, this time as an ESA-Roscosmos collaboration.

Elena installing PK-4

Planet conceptions

By changing the parameters in PK-4, such as adjusting voltage or using larger dust particles, the atom doppelgangers can simulate different interactions. Complex phenomena such as phase transitions, for example from gas to liquid, microscopic motions, the onset of turbulence and shear forces are well known in physics, but not fully understood at the atomic level.

Plasma Kristall-4

Using PK-4, researchers across the world can follow how an object melts, how waves spread in fluids and how currents change at the atomic level.  

Around 100 papers have been published based on the Plasma Kristall experiments and the knowledge gained is helping understand how planets form too. At its origin our planet Earth was probably two dust particles that met in space and grew and grew into our world. PK-4 can model these origin moments as they are during the conception of planets.

CADMOS during PK-4 operations

The huge amount of data that PK-4 creates is so vast it cannot be downloaded through the Space Station’s communication network, so hard disks are physically shipped to space and back with terabytes of information. The experiment is run from Toulouse, France, at the CNES space agency operating centre Cadmos.

Astrid Orr, ESA’s physical sciences coordinator notes “PK-4 is a great example of fundamental science done on the Space Station; through international collaboration and long-term investment we are learning more about the world around us, on the minute scale as well as on the cosmic scale.

Plasma care

“The knowledge from the PK experiments can be directly applied to research on fusion physics – where dust needs to be removed – and the processing of electronic chips, for example in plasma processes in the semiconductor and solar cell industry. In addition, the miniaturisation of the technology required when developing Plasma Kristal is already being applied in plasma-based medical equipment for hospitals.

“The PK experiments address a large range of physical phenomena, so ground-breaking discoveries can happen at any moment.”

Related links:

Plasma-based medical equipment for hospitals: https://www.esa.int/Applications/Telecommunications_Integrated_Applications/Technology_Transfer/Plasma_medicine_how_space_science_improves_patient_care

Research: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/Research

Human and Robotic Exploration: https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration

Science & Exploration: https://www.esa.int/Science_Exploration

International Space Station (ISS): https://www.esa.int/Science_Exploration/Human_and_Robotic_Exploration/International_Space_Station

Images, Animation, Text, Credits: ESA/NASA–T. Pesquet/DLR/Michael Kretschmer/CNES/terraplasma medical.

Greetings, Orbiter.ch

Russian Cargo Ship Docks to Station After Two-Day Trip

 






ROSCOSMOS - Russian Vehicles patch.


July 2, 2021


Image above: July 1, 2021: International Space Station Configuration. Five spaceships are parked at the space station including the SpaceX Crew Dragon and Cargo Dragon spaceships and Russia’s Soyuz MS-18 crew ship and ISS Progress 77 and 78 resupply ships. Image Credit: NASA.

An uncrewed Russian Progress 78 spacecraft arrived at the International Space Station’s Poisk module on the space-facing side of the Russian segment at 8:59 p.m. EDT, two days after lifting off from the Baikonur Cosmodrome in Kazakhstan Sunday, Tuesday June 29 at 7:27 p.m. (4:27 a.m. Wednesday, June 30, Baikonur time). The spacecraft were flying over southeast Pacific Ocean off the coast of Chile at the time of docking.

Progress MS-17 docking

Carrying more than 3,600 pounds of food, fuel, and supplies for the Expedition 65 crew, the Progress 78 resupply spacecraft will spend almost five months at the station. The cargo craft is scheduled to perform an automated undocking and relocation to the new “Nauka” Multipurpose Laboratory Module in late October. Named for the Russian word for “science,” Nauka is planned to launch to the space station in July.

Related articles:

Fragment of Falcon 9 rocket can approach Progress MS-17 spacecraft
https://orbiterchspacenews.blogspot.com/2021/06/fragment-of-falcon-9-rocket-can.html

Russian Resupply Ship Blasts Off on Two-Day Trip to Station
https://orbiterchspacenews.blogspot.com/2021/06/russian-resupply-ship-blasts-off-on-two.html

Related link:

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

Image (mentioned), Video, Text, Credits: NASA/Mark Garcia/NASA TV/Roscosmos/SciNews.

Greetings, Orbiter.ch

jeudi 1 juillet 2021

Station Crew Busy with Cargo Ship Ops and Space Research

 







ISS - Expedition 65 Mission patch.


July 1, 2021

Cargo operations continue at the International Space Station as a Russian resupply ship gets ready for docking tonight and a U.S. spaceship prepares for undocking next week. The Expedition 65 crew is also staying focused today on life science and physics research.

Russia’s ISS Progress 78 cargo craft is orbiting Earth today fine-tuning its maneuvers as it heads toward the orbiting lab. Cosmonauts Oleg Novitskiy and Pyotr Dubrov will be monitoring Progress as it approaches the station’s Poisk module for an automated docking at 9:03 p.m. EDT. NASA TV begins its live broadcast at 8:15 p.m. on the agency’s website and the NASA app.

Progress MS-1 cargo craft. Image Credit: ROSCOSMOS

NASA Flight Engineers Megan McArthur, Shane Kimbrough and Mark Vande Hei joined Flight Engineer Thomas Pesquet of ESA (European Space Agency) on Thursday and continued readying the Cargo Dragon for its undocking on July 6 at 11:05 a.m. EDT. The quartet is packing and organizing Dragon before final loading of critical research samples begins on Monday for analysis back on Earth.

Microgravity research has been proceeding apace as always with the astronauts exploring an array of space phenomena today. Commander Akihiko Hoshide worked on the Plant Habitat Facility throughout the day preparing for upcoming botany research. McArthur peered at protein crystals through a microscope before investigating how microgravity affects bacteria.


Image above: Expedition 65 Flight Engineer Megan McArthur works on a protein crystal experiment potentially benefitting pharmaceutical and biotechnology companies on Earth. Image Credit: NASA.

Kimbrough conducted operations inside the Microgravity Science Glovebox exploring ways to harness nanoparticles to fabricate and manufacture new materials. Vande Hei serviced the Cold Atom Lab, a research device that explores the physics of temperatures near absolute zero, preparing some components for return to Earth aboard Dragon next week.

Related links:

Expedition 65: https://www.nasa.gov/mission_pages/station/expeditions/expedition65/index.html

Poisk module: https://www.nasa.gov/mission_pages/station/structure/elements/poisk-mini-research-module-2

NASA TV: https://www.nasa.gov/nasalive

Plant Habitat Facility: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=2036

Protein crystals: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8073

How microgravity affects bacteria: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=8160

Microgravity Science Glovebox: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=341

Harness nanoparticles: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Investigation.html?#id=7669

Cold Atom Lab: https://www.nasa.gov/mission_pages/station/research/experiments/explorer/Facility.html?#id=7396

Space Station Research and Technology: https://www.nasa.gov/mission_pages/station/research/overview.html

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

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

Best regards, Orbiter.ch

NASA’s Self-Driving Perseverance Mars Rover ‘Takes the Wheel’

 







NASA - Mars 2020 Perseverance Rover patch.


July 1, 2021

The agency’s newest rover is trekking across the Martian landscape using a newly enhanced auto-navigation system.

NASA's Perseverance Mars Rover's First Autonav Drive

Video above: Perseverance relies on left and right navigation cameras. The view seen here combines the perspective of two cameras rover during the rover’s first drive using AutoNav, it’s auto-navigation function. Video Credits: NASA/JPL-Caltech.

NASA’s newest six-wheeled robot on Mars, the Perseverance rover, is beginning an epic journey across a crater floor seeking signs of ancient life. That means the rover team is deeply engaged with planning navigation routes, drafting instructions to be beamed up, even donning special 3D glasses to help map their course.

But increasingly, the rover will take charge of the drive by itself, using a powerful auto-navigation system. Called AutoNav, this enhanced system makes 3D maps of the terrain ahead, identifies hazards, and plans a route around any obstacles without additional direction from controllers back on Earth.

“We have a capability called ‘thinking while driving,’” said Vandi Verma, a senior engineer, rover planner, and driver at NASA’s Jet Propulsion Laboratory in Southern California. “The rover is thinking about the autonomous drive while its wheels are turning.”

That capability, combined with other improvements, might enable Perseverance to hit a top speed of 393 feet (120 meters) per hour; its predecessor, Curiosity, equipped with an earlier version of AutoNav, covers about 66 feet (20 meters) per hour as it climbs Mount Sharp to the southeast.


Image above: Vandi Verma, an engineer who now works with NASA’s Perseverance Mars rover, is seen here working as a driver for the Curiosity rover. The special 3D glasses she’s wearing are still used by rover drivers to easily detect changes in terrain that the rover may need to avoid. Image Credits: NASA/JPL-Caltech.

“We sped up AutoNav by four or five times,” said Michael McHenry, the mobility domain lead and part of JPL’s team of rover planners. “We’re driving a lot farther in a lot less time than Curiosity demonstrated.”

As Perseverance begins its first science campaign on the floor of Jezero Crater, AutoNav will be a key feature in helping get the job done.

This crater once was a lake, when, billions of years ago, Mars was wetter than today, and Perseverance’s destination is a dried-out river delta at the crater’s edge. If life ever took hold on early Mars, signs of it might be found there. The rover will gather samples over some 9 miles (15 kilometers), then prep the samples for collection by a future mission that would take them back to Earth for analysis.

“We’re going to be able to get to places the scientists want to go much more quickly,” said Jennifer Trosper, who has worked on every one of NASA’s Martian rovers and is the Mars 2020 Perseverance rover project manager. “Now we are able to drive through these more complex terrains instead of going around them: It’s not something we’ve been able to do before.”

Computer Simulation of Perseverance's First Autonav Drive

Video above: This computer simulation shows NASA’s Perseverance Mars rover as it carried out its first drive using its auto-navigation feature, which allows it to avoid rocks and other hazards without input from engineers back on Earth. Video Credits: NASA/JPL-Caltech.

The Human Element

Of course, Perseverance can’t get by on AutoNav alone. The involvement of the rover team remains critical in planning and driving Perseverance’s route. An entire team of specialists develops a navigation route along with planning the rover’s activity, whether it’s examining a geologically interesting feature on the way to its destination or, soon, taking samples.

Because of the radio signal delay between Earth and Mars, they can’t simply move the rover forward with a joystick. Instead, they scrutinize satellite images, sometimes donning those 3D glasses to view the Martian surface in the rover’s vicinity. Once the team signs off, they beam the instructions to Mars, and the rover executes those instructions the following day.

Perseverance’s wheels were modified as well to help with just how swiftly those plans are executed: Along with being slightly greater in diameter and narrower than Curiosity’s wheels, they each feature 48 treads that look like slightly wavy lines, as opposed to Curiosity’s 24 chevron-pattern treads. The goals were to help with traction as well as durability.

“Curiosity couldn’t AutoNav because of the wheel-wear issue,” Trosper said. “Early in the mission, we experienced small, sharp, pointy rocks starting to put holes in the wheels, and our AutoNav didn’t avoid those.”

Mars Perseverance Rover. Image Credits: NASA/JPL-Caltech

Higher clearance for Perseverance’s belly also enables the rover to roll safely over rougher ground – including good-size rocks. And Perseverance’s beefed-up auto-navigation capabilities include ENav, or enhanced navigation, an algorithm-and-software combination that allows more precise hazard detection.

Unlike its predecessors, Perseverance can employ one of its computers just for navigation on the surface; its main computer can devote itself to the many other tasks that keep the rover healthy and active.

This Vision Compute Element, or VCE, guided Perseverance to the Martian surface during its entry, descent, and landing in February. Now it’s being used full-time to map out the rover’s journey while helping it avoid trouble along the way.

The rover also keeps track of how far it’s moved from one spot to another using a system called “visual odometry.” Perseverance periodically captures images as it moves, comparing one position to the next to see if it moved the expected distance.

Team members say they look forward to letting AutoNav “take the wheel.” But they’ll also be ready to intervene when needed.

And just what is it like to drive on Mars? The planners and drivers say it never gets old.

“Jezero is incredible,” Verma said. “It’s a rover driver’s paradise. When you put on the 3D glasses, you see so much more undulation in the terrain. Some days I just stare at the images.”

Perseverance Mars Rover: http://www.nasa.gov/perseverance

Images (mentioned), Videos (mentioned), Text, Credits: NASA/Tony Greicius/Karen Fox/Josh Handal/JPL/Andrew Good.

Greetings, Orbiter.ch

Chandra Turns Up the Heat in the Milky Way Center

 







NASA - Chandra X-ray Observatory logo.


July 1, 2021


This 2004 image was produced by combining a dozen observations from the Chandra X-Ray Observatory made of a 130 light-year region in the center of the Milky Way. The colors represent low (red), medium (green) and high (blue) energy X-rays. Thanks to Chandra's unique resolving power, astronomers have now been able to identify thousands of point-like X-ray sources due to neutron stars, black holes, white dwarfs, foreground stars, and background galaxies. What remains is a diffuse X-ray glow extending from the upper left to the lower right, along the direction of the disk of the Galaxy.

The spectrum of the diffuse glow is consistent with a hot gas cloud that contains two components – 10-million-degree Celsius gas and 100-million-degree gas. The diffuse X-rays appear to be the brightest part of a ridge of X-ray emission that stretches for several thousand light years along the disk of the Galaxy. The extent of this ridge implies that the diffuse hot gas in this image is probably not being heated by the supermassive black hole at the center of the Milky Way, known to astronomers as "Sgr A*".

Chandra X-ray Observatory

Chandra is part of NASA's fleet of "Great Observatories" along with the Hubble Space Telescope and the Spitzer Space Telescope. Chandra allows scientists from around the world to obtain X-ray images of exotic environments to help understand the structure and evolution of the universe.

Chandra X-Ray Observatory: https://www.nasa.gov/mission_pages/chandra/main/index.html

Image, Animation, Text Credits: NASA/CXC/UCLA/MIT/M.Muno et al./NASA/Yvette Smith.

Best regards, Orbiter.ch