vendredi 21 décembre 2018

Successful launch of a Proton-M launch vehicle with a Russian spacecraft for the Ministry of Defense


December 21, 2018

Proton-M carrying Blagovest No. 13L lift off

Today, December 21, the Proton-M space rocket with a spacecraft was launched from the Baikonur cosmodrome in the interests of the Russian Ministry of Defense.

All prelaunch operations, launch and flight of the Proton-M launch vehicle were carried out in the normal mode. The successful launch of the spacecraft into the target orbit was provided by the Briz-M upper stage.

The new satellite has been accepted for control by the ground-based means of the Air and Space Forces (VKS) of Russia.

Video above: Launch of the Proton-M launch vehicle with a Russian spacecraft for the Ministry of Defense. Video Credit: Roscosmos TV.

It was the 2nd in 2018 and the 418th launch in the history of the Proton launch vehicle, (including all its modifications).

The Proton carrier rocket and the Briz-M upper stage were developed and mass-produced by the Center named after M. V. Khrunichev. The Proton-M PH is an upgraded version of the heavy-duty Proton carrier rocket with improved operational and environmental performance. Thanks to the use of the Briz-M upper stage, the Proton-M rocket is capable of delivering a payload of more than 6 tons to a geotransition orbit. The first launch of the Proton-M booster with the upper stage Breeze-M took place on April 7, 2001 of the year. Since then, this modification of the Proton rocket has been used in the 104th space launches.

Blagovest No. 13L satellite

The Blagovest No. 13L communications satellite to cover Russian territory and provide high-speed Internet, television and radio broadcast, and voice and video conferencing services for Russian domestic and military users.

Roscosmos Press Release:

Images, Video (mentioned), Text, Credits: ROSCOSMOS/Günter Space Page/ Aerospace/Roland Berga.


Space Station Science Highlights: Week of December 17, 2018

ISS - Expedition 57 Mission patch / ISS - Expedition 58 Mission patch.

Dec. 21, 2018

After contributing to hundreds of experiments in biology, biotechnology, physical science and Earth science aboard the world-class orbiting laboratory, three members of the International Space Station’s Expedition 57 crew, including NASA astronaut Serena Auñón-Chancellor, returned to Earth Thursday, safely landing at 12:02 a.m. EST (11:02 a.m. local time) in Kazakhstan.

Image above: Expedition 57 crew members Alexander Gerst of ESA, Sergey Prokopyev of Roscosmos, and Serena Auñón-Chancellor of NASA sit inchairs outside the Soyuz MS-09 spacecraft after landing in a remote area near the town of Zhezkazgan, Kazakhstan. Image Credit: NASA.

The Expedition 57 crew Highlights included investigations into new cancer treatment methods and algae growth in space. The crew also installed a new Life Sciences Glovebox, a sealed work area for life science and technology investigations that can accommodate two astronauts.

Here’s a look at some of the science conducted this week aboard the orbiting lab:

Investigation studies dexterity in space

Microgravity provides a unique environment to study dexterous manipulation. The European Space Agency’s GRIP investigation studies long-duration spaceflight effects on the abilities of human subjects to regulate grip force and upper limb trajectories when manipulating objects using different kinds of movements (e.g. oscillatory movements, rapid discrete movements and tapping gestures), while restrained in the seated or supine position. This week, the crew performed the GRIP science tasks restrained to a chair in the supine, or lying facing upward, position.

Data collected from this investigation may provide insight into potential hazards for astronauts as they manipulate objects in different gravitational environments. It could also support design and control of haptic interfaces to be used in challenging environments, and provide information about motor control that potentially will be useful for the evaluation and rehabilitation of patients with neurological diseases on Earth.

Crew provides blood and saliva for immune study

Protecting crew health is important as NASA prepares for long duration, deep-space missions. Functional Immune studies previously uninvestigated areas of the body’s immune response, and if spaceflight alters a crew member’s susceptibility to disease.

Image above: ESA astronaut Alexander Gerst completes a blood collection with the help of NASA astronaut Serena Auñón-Chancellor. Image Credit: NASA.

The immune system is a complex weaving of biological structures and processes. Decreased activity in just one piece can cause changes in disease risk within the human body. Studies have shown that microgravity modifies the immune system. This may create an environment where rashes, unusual allergies and latent virus reactivation may present themselves in some crew members.

This week as a part of Functional Immune, the crew provided blood and saliva samples to be used to determine the changes taking place in crewmembers’ immune systems during flight.

Airway Monitoring

With dust particles present in the space station atmosphere, Airway Monitoring studies the occurrence and indicators of airway inflammation in crewmembers, using ultra-sensitive gas analyzers to evaluate exhaled air. This helps to highlight any health impacts and to maintain crewmember well-being on future human spaceflight missions. This is especially important on longer-duration missions – for example, to the Moon and Mars - where crewmembers will have to be more self-sufficient in identifying and avoiding such conditions. This kind of research may also benefit similar conditions, such as asthma, on Earth.

This week, the crew completed Low nitric oxide (NO) and High NO measurements for the ambient pressure session in the Destiny Laboratory.

Image above: David Saint-Jacques, of the Canadian Space Agency, completes the Bone Densitometer calibration in support of the Rodent Research-8 investigation. Image Credit: NASA.

Other work was performed on these investigations:

- The Spaceflight-induced Hypoxic/ROS Signaling (APEX-05) experiment grows different wild and mutant varieties of Arabidopsis thaliana, in order to understand how their genetic and molecular stress response systems work in space:

- CASIS PCG 16 evaluates growth of LRRK2 protein crystals in microgravity. LRRK2 is implicated in Parkinson’s disease, but crystals of the protein grown on Earth are too small and compact to study:

- Rodent Research-8 (RR-8) examines the physiology of aging and the effect of age on disease progression using groups of young and old mice flown in space and kept on Earth:

- The Bone Densitometer uses X-rays to measure the bone mineral density (and the lean and fat tissue) of mice living aboard the station. As a result, researchers hope to develop medical technology that will combat bone density loss in space and on Earth, helping millions of senior citizens who suffer from osteoporosis:

- Hydrogels are often used for tissue regeneration purposes due to their high water content and how easily they can be customized.  Hydrogel Formation and Drug Release in Microgravity Conditions takes advantage of reduced fluid motion in microgravity to more precisely study behavior of the gel and its potential as a wound-healing patch:

Space to Ground: Holiday Homecoming: 12/21/2018

Related links:

Expedition 57:

Expedition 58:

New cancer treatment methods:

Algae growth in space:

Life Sciences Glovebox:


Functional Immune:

Airway Monitoring:

Spot the Station:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Video (NASA), Text, Credits: NASA/Michael Johnson/Vic Cooley, Lead Increment Scientist Expeditions 57/58.

Best regards,

Lucy Finds Its Place in the Solar System: Navigating NASA’s First Mission to the Trojan Asteroids

NASA - LUCY Mission patch.

Dec. 21, 2018

In science fiction, explorers can hop in futuristic spaceships and traverse half the galaxy in the blink of a plot hole. However, this sidelines the navigational acrobatics required in order to guarantee real-life mission success.

In 2021, the feat of navigation that is the Lucy mission will launch. To steer Lucy towards its targets doesn’t simply involve programming a map into a spacecraft and giving it gas money – it will fly by six asteroid targets, each in different orbits, over the course of 12 years.

Image above: This diagram illustrates Lucy's orbital path. The spacecraft’s path (green) is shown in a frame of reference where Jupiter remains stationary, giving the trajectory its pretzel-like shape. After launch in October 2021, Lucy has two close Earth flybys before encountering its Trojan targets. In the L4 cloud Lucy will fly by (3548) Eurybates (white), (15094) Polymele (pink), (11351) Leucus (red), and (21900) Orus (red) from 2027-2028. After diving past Earth again Lucy will visit the L5 cloud and encounter the (617) Patroclus-Menoetius binary (pink) in 2033. As a bonus, in 2025 on the way to the L4, Lucy flies by a small Main Belt asteroid, (52246) Donaldjohanson (white), named for the discoverer of the Lucy fossil. After flying by the Patroclus-Menoetius binary in 2033, Lucy will continue cycling between the two Trojan clouds every six years. Image Credits: Southwest Research Institute.

Lucy’s destination is among Jupiter’s Trojan asteroids, clusters of rocky bodies almost as old as the Sun itself, and visiting these asteroids may help unlock the secrets of the early solar system. Lucy will encounter a Main Belt asteroid in 2025, where it will conduct a practice run of its instruments before encountering the first four Trojan targets from 2027-2028. In 2033, Lucy will end its mission with a study of a binary system of two Trojans orbiting each other.

Getting the spacecraft where it needs to go is a massive challenge. The solar system is in constant motion, and gravitational forces will pull on Lucy at all times, especially from the targets it aims to visit. Previous missions have flown by and even orbited multiple targets, but none so many as will Lucy.

Scientists and engineers involved with trajectory design have the responsibility of figuring out that route, under Flight Dynamics Team Leader Kevin Berry of NASA’s Goddard Space Flight Center in Greenbelt, Maryland. One such engineer is Jacob Englander, the optimization technical lead for the Lucy mission. “There are two ways to navigate a mission like Lucy,” he said. “You can either burn an enormous amount of propellant and zig-zag your way around trying to find more targets, or you can look for an opportunity where they just all happen to line up perfectly.” To visit these aligned targets, the majority of Lucy’s high-speed lane changes will come from gravity assists, with minimal use of fueled tweaks.

Though Lucy is programmed to throw itself out into a celestial alignment that will not occur for decades, it cannot be left to its own devices. Once the spacecraft begins to approach its asteroid targets, optical navigation is the next required step.

“OpNav,” as optical navigation technical lead Coralie Adam refers to it, is the usage of imagery from the on-board cameras to determine Lucy’s position relative to the target. This is a useful measurement used by the navigation team to tweak Lucy’s route and ensure it stays on the nominal flyby path. Adam works in Simi Valley, California, with KinetX, the company NASA selected to conduct Lucy’s deep space navigation.

Image above: Lucy will explore six Jupiter Trojan asteroids. These asteroids are trapped by Jupiter's gravity in two swarms that share the planet's orbit, one leading and one trailing Jupiter in its 12-year circuit around the sun. The Trojans are thought to be relics of a much earlier era in the history of the solar system, and may have formed far beyond Jupiter's current orbit. Image Credit: NASA.

By using the communications link from the spacecraft to Earth, Adam said, the Lucy team gets information about the spacecraft’s location, direction and velocity. The spacecraft takes pictures and sends them down to Earth, where Adam and other optical navigators use software to determine where the picture was taken based on the location of stars and the target. The orbit determination team uses this data along with data from the communications link to solve for where the spacecraft is and where it is expected to be, relative to the Trojans. The team then designs a trajectory correction maneuver to get Lucy on track. “The first maneuver is tiny,” said navigation technical lead Dale Stanbridge, who is also of KinetX. “But the second one is at 898 meters per second. That’s a characteristic of Lucy: very large delta V maneuvers.” Delta V refers to the change in speed during the maneuver.

Communicating all of these navigation commands with Lucy is a process all on its own. “Lockheed Martin sends the commands to the spacecraft via the Deep Space Network,” Adam said. “What we do is we work with Lockheed and the Southwest Research Institute, where teams are sequencing the instruments and designing how the spacecraft is pointed, to make sure Lucy takes the pictures we want when we want them.”

“The maneuvers to correct Lucy’s trajectory are all going to be really critical because the spacecraft must encounter the Trojan at the intersection of the spacecraft and Trojan orbital planes,” Stanbridge said. “Changing the spacecraft orbital plane requires a lot of energy, so the maneuvers need to be executed at the optimal time to reach to next body while minimizing the fuel cost.”

While Lucy is conducting deep space maneuvers to correct its trajectory toward its targets, communications with the spacecraft are sometimes lost for brief periods. “Blackout periods can be up to 30 minutes for some of our bigger maneuvers,” Stanbridge said. “Other times you could lose communications would be when, for example, the Sun, comes between the Earth tracking station and the spacecraft, where the signal would be degraded by passing through the solar plasma.”

Losing contact isn’t disastrous, though. “We have high-fidelity predictions of the spacecraft trajectory which are easily good enough to resume tracking the spacecraft when the event causing a communication loss is over,” Stanbridge said.

What route will Lucy take once its mission is complete, nearly 15 years from now? “We’re just going to leave it out there,” Englander said. “We did an analysis to see if it passively hits anything, and looking far into the future, it doesn’t.” The Lucy team has given the spacecraft a clear path for thousands of years, long after Lucy has rewritten the textbooks on our solar system’s history.

The Lucy mission is led by Principal Investigator Dr. Hal Levison from Southwest Research Institute in Boulder, Colorado. NASA Goddard in Greenbelt, Maryland, manages the mission. Lockheed Martin Space in Denver will build the spacecraft and conduct mission operations.

For more information about NASA's Lucy mission, visit:

Images (mentioned), Text, Credits: NASA/Bill Steigerwald/Goddard Space Flight Center, by Tamsyn Brann.


Holiday Asteroid Imaged with NASA Radar

Asteroid Watch logo.

December 21, 2018

Image above: These three radar images of near-Earth asteroid 2003 SD220 were obtained on Dec. 15-17, by coordinating observations with NASA's 230-foot (70-meter) antenna at the Goldstone Deep Space Communications Complex in California and the National Science Foundation's (NSF) 330-foot (100-meter) Green Bank Telescope in West Virginia. Image Credits: NASA/JPL-Caltech/GSSR/NSF/GBO.

The December 2018 close approach by the large, near-Earth asteroid 2003 SD220 has provided astronomers an outstanding opportunity to obtain detailed radar images of the surface and shape of the object and to improve the understanding of its orbit.

The asteroid will fly safely past Earth on Saturday, Dec. 22, at a distance of about 1.8 million miles (2.9 million kilometers). This will be the asteroid's closest approach in more than 400 years and the closest until 2070, when the asteroid will safely approach Earth slightly closer.

The radar images reveal an asteroid with a length of at least one mile (1.6 kilometers) and a shape similar to that of the exposed portion of a hippopotamus wading in a river. They were obtained Dec. 15-17 by coordinating the observations with NASA's 230-foot (70-meter) antenna at the Goldstone Deep Space Communications Complex in California, the National Science Foundation's 330-foot (100-meter) Green Bank Telescope in West Virginia and the Arecibo Observatory's 1,000-foot (305-meter) antenna in Puerto Rico.

The Green Bank Telescope was the receiver for the powerful microwave signals transmitted by either Goldstone or the NASA-funded Arecibo planetary radar in what is known as a "bistatic radar configuration." Using one telescope to transmit and another to receive can yield considerably more detail than would one telescope, and it is an invaluable technique to obtain radar images of closely approaching, slowly rotating asteroids like this one.

Image above: These two radar images of near-Earth asteroid 2003 SD220 were obtained on Dec. 18 and 19 by coordinating observations with the Arecibo Observatory's 1,000-foot (305-meter) antenna in Puerto Rico and the National Science Foundation's (NSF) 330-foot (100-meter) Green Bank Telescope in West Virginia. The radar images reveal the asteroid is at least one mile (1.6 kilometers) long. Image Credits: NASA/Arecibo/USRA/UCF/GBO/NSF.

"The radar images achieve an unprecedented level of detail and are comparable to those obtained from a spacecraft flyby," said Lance Benner of the Jet Propulsion Laboratory in Pasadena, California, and the scientist leading the observations from Goldstone. "The most conspicuous surface feature is a prominent ridge that appears to wrap partway around the asteroid near one end. The ridge extends about 330 feet [100 meters] above the surrounding terrain. Numerous small bright spots are visible in the data and may be reflections from boulders. The images also show a cluster of dark, circular features near the right edge that may be craters."

The images confirm what was seen in earlier "light curve" measurements of sunlight reflected from the asteroid and from earlier radar images by Arecibo: 2003 SD220 has an extremely slow rotation period of roughly 12 days. It also has what seems to be a complex rotation somewhat analogous to a poorly thrown football. Known as "non-principal axis" rotation, it is uncommon among near-Earth asteroids, most of which spin about their shortest axis.

Image above: The Great Big Thing - National Radio Astronomy Observatory. Image Credit: National Radio Astronomy Observatory.

With resolutions as fine as 12 feet (3.7 meters) per pixel, the detail of these images is 20 times finer than that obtained during the asteroid's previous close approach to Earth three years ago, which was at a greater distance. The new radar data will provide important constraints on the density distribution of the asteroid's interior - information that is available on very few near-Earth asteroids.

"This year, with our knowledge about 2003 SD220's slow rotation, we were able to plan out a great sequence of radar images using the largest single-dish radio telescopes in the nation," said Patrick Taylor, senior scientist with Universities Space Research Association (USRA) at the Lunar and Planetary Institute (LPI) in Houston.

"The new details we've uncovered, all the way down to 2003 SD220's geology, will let us reconstruct its shape and rotation state, as was done with Bennu, target of the OSIRIS-REx mission," said Edgard Rivera-Valentín, USRA scientist at LPI. "Detailed shape reconstruction lets us better understand how these small bodies formed and evolved over time."

Patrick Taylor led the bistatic radar observations with Green Bank Observatory, home of the Green Bank Telescope, the world's largest fully steerable radio telescope. Rivera-Valentín will be leading the shape reconstruction of 2003 SD220 and led the Arecibo Observatory observations.

Arecibo Observatory. Image Credit: Wikipedia

Asteroid 2003 SD220 was discovered on Sept. 29, 2003, by astronomers at the Lowell Observatory Near-Earth-Object Search (LONEOS) in Flagstaff, Arizona - an early Near-Earth Object (NEO) survey project supported by NASA that is no longer in operation. It is classified as being a "potentially hazardous asteroid" because of its size and close approaches to Earth's orbit. However, these radar measurements further refine the understanding of 2003 SD220's orbit, confirming that it does not pose a future impact threat to Earth.

The Arecibo, Goldstone and USRA planetary radar projects are funded through NASA's Near-Earth Object Observations Program within the Planetary Defense Coordination Office(PDCO), which manages the Agency's Planetary Defense Program. The Arecibo Observatory is a facility of the National Science Foundation operated under cooperative agreement by the University of Central Florida, Yang Enterprises and Universidad Metropolitana. GBO is a facility of the National Science Foundation, operated under a cooperative agreement by Associated Universities, Inc.

JPL hosts the Center for Near-Earth Object Studies (CNEOS) for NASA's Near-Earth Object Observations Program.

More information about CNEOS, asteroids and near-Earth objects can be found at:

For more information about NASA's Planetary Defense Coordination Office, visit:

More information about the National Science Foundation's Arecibo Observatory can be found at:

Planetary Defense Coordination Office (PDCO):

Images (mentioned), Text, Credits: NASA/Dwayne Brown/JoAnna Wendel/JPL/DC Agle/National Radio Astronomy Observatory/Charles Blue/Arecibo Observatory/Ricardo Correa.


ESA’s e.Deorbit debris removal mission reborn as servicing vehicle

ESA - Clean Space logo.

21 December 2018

ESA’s proposed e.Deorbit mission to take down a derelict satellite is being reborn in a wider role, as a new space servicing vehicle to perform a variety of different roles in orbit, including the refuelling, refurbishing or reboosting of satellites already in orbit.

ESA’s Clean Space initiative began developing the mission in 2013, organised around the deceptively simple task of capturing and safely deorbiting a derelict ESA-owned satellite in highly trafficked low-Earth orbit. The target was the Envisat Earth-observing satellite, which after 10 years of monitoring our homeworld, had failed unexpectedly the previous year.

Infrared and visible imaging of model satellite

Space Shuttle astronauts had captured errant satellites during the 1980s, but there was no precedent for the autonomous robotic capture of such an uncooperative target.

Work began on identifying the novel technologies that would need to be developed, including the type of capture mechanism to be used – from robotic arms to nets or even a harpoon. Also required was precise enoughguidance navigation and control system to safely close in and secure such a large, unpredictably tumbling target.

This took place as part of initial ‘Phase A’ studies by two parallel companies, followed up by detailed ‘Phase B1’ studies to shape its preliminary design, ready for follow-up implementation.

Concurrent Design Facility

Along with the innovative technologies under discussion, these Phase B1 activities made a little bit of ESA history in their own right, as the first such studies to be based around model-based system engineering – employing detailed software models of the satellite as the baseline engineering tool, rather than traditional written documentation.

Following these studies the decision has been made to widen the scope of the mission. It took so many advanced technologies to make such an act of active debris removal possible that the possibility is there to apply it to a recurrent space servicing cehicle design.

Of increasing industrial interest in recent years, this would be a ‘Swiss Army knife’ of a satellite with the agility, capability and autonomy to perform all kinds of complex tasks in space, such as refuelling high-value satellites reaching the end of their lives, adding new equipment to them, or attaching to them to move them to new orbits.

Robotic arm

Active debris removal is seen as particularly valuable for the imminent age of megaconstellations, when hundreds or even thousands of satellites will be formation flying in low orbits to offer low-latency telecommunications or global high-repeat Earth observation coverage.

Any failing satellite that breaks ranks might threaten the entire constellation around it, so dedicated space servicing vehicles especially tailored for the role could well play an essential ‘sheepdog’ role within megaconstellations.

Targeting satellite

In addition, a more general-purpose Space Servicing Vehicle could potentially be contracted to take down derelict satellites as one of its roles – a return to the original thinking behind e.Deorbit. Back in 2012, the initial approach taken was to invite companies to take down Envisat on a service-oriented basis, but it was seen as too risky a challenge.

“Today we have the funding to develop relevant technologies but not to actually remove a defunct satellite,” explains Luisa Innocenti, heading Clean Space. “Instead, we have asked industry to make proposals to remove a defunct ESA object while demonstrating in-orbit servicing – the new path to a potentially very valuable business.”

Clean Space:

Images, Text, Credits: ESA/G. Porter/David Ducros/CC BY-SA 3.0 IGO/Airbus Defence and Space.


International Crew to Ring in Christmas 50 Years After First Moon Trip

ISS - Expedition 58 Mission patch.

December 21, 2018

Three people from the U.S., Canada and Russia are orbiting Earth today getting ready to observe Christmas and experience New Year’s Eve from space aboard the International Space Station. Back on Earth, another three station crew members have returned to their home bases just 24 hours after completing a 197-day mission aboard the orbital lab.

Image above: The official Expedition crew portrait with (from left) NASA astronaut Anne McClain, Roscosmos cosmonaut Oleg Kononenko and astronaut David Saint-Jacques of the Canadian Space Agency. Image Credit: NASA.

The first time three humans spent Christmas in space was 50 years ago in 1968 during Apollo 8 and was also the first time a crew orbited the Moon. This Christmas astronauts Anne McClain of NASA and David Saint-Jacques of the Canadian Space Agency with cosmonaut Oleg Kononenko of Roscosmos will be soaring about 250 miles above the Earth’s surface in a much larger spacecraft. The Expedition 58 trio will share a traditional meal aboard the orbital lab, share gifts and call down to family during their off-duty day.

Kononenko is beginning his fourth mission on the station and will spend his second Christmas in space. McClain and Saint-Jacques are getting used to life in space for the first time and will return to Earth in June with Kononenko.

International Space Station (ISS). Image Credit: NASA

NASA astronaut Serena Auñón-Chancellor returned to Houston late Thursday just one day after landing in Kazakhstan wrapping up her six-and-a-half month stay aboard the orbital lab. She parachuted to Earth inside the Soyuz MS-09 spacecraft with her Expedition 57 crewmates Alexander Gerst of ESA (European Space Agency) and Sergey Prokopyev of Roscosmos.

Related article:

A Bold Step: Apollo 8 Sends First Human Flight Beyond Earth

Related links:

Expedition 57:

Expedition 58:

Apollo 8:

Space Station Research and Technology:

International Space Station (ISS):

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

Best regards,

Hubble’s Cosmic Holiday Wreath

NASA - Hubble Space Telescope patch.

Dec. 21, 2018

This festive NASA Hubble Space Telescope image resembles a holiday wreath made of sparkling lights. The bright southern hemisphere star RS Puppis, at the center of the image, is swaddled in a gossamer cocoon of reflective dust illuminated by the glittering star. The super star is ten times more massive than the Sun and 200 times larger.

RS Puppis rhythmically brightens and dims over a six-week cycle. It is one of the most luminous in the class of so-called Cepheid variable stars. Its average intrinsic brightness is 15,000 times greater than the Sun's luminosity.

The nebula flickers in brightness as pulses of light from the Cepheid propagate outwards. Hubble took a series of photos of light flashes rippling across the nebula in a phenomenon known as a "light echo." Even though light travels through space fast enough to span the gap between Earth and the Moon in a little over a second, the nebula is so large that reflected light can actually be photographed traversing the nebula.

By observing the fluctuation of light in RS Puppis itself, as well as recording the faint reflections of light pulses moving across the nebula, astronomers are able to measure these light echoes and pin down a very accurate distance. The distance to RS Puppis has been narrowed down to 6,500 light-years (with a margin of error of only one percent).

Hubble Space Telescope (HST)

For more information about Hubble, visit:

Image, Animation, Credits: NASA, ESA and the Hubble Heritage Team (STScI/AURA) – Hubble/Europe Collaboration; Acknowledgement: H. Bond (STScI and Pennsylvania State University)/Text Credits: Space Telescope Science Institute (STScI)/NASA/Karl Hille.

Season's Greetings,

The Coolest Experiment in the Universe

ISS - International Space Station logo.

December 21, 2018

Image above: The International Space Station, shown here in 2018, is home to many scientific experiments, including NASA's Cold Atom Laboratory. Image Credit: NASA.

What's the coldest place you can think of? Temperatures on a winter day in Antarctica dip as low as -120ºF (-85ºC). On the dark side of the Moon, they hit -280ºF (-173ºC). But inside NASA's Cold Atom Laboratory on the International Space Station, scientists are creating something even colder.

The Cold Atom Lab (CAL) is the first facility in orbit to produce clouds of "ultracold" atoms, which can reach a fraction of a degree above absolute zero: -459ºF (-273ºC), the absolute coldest temperature that matter can reach. Nothing in nature is known to hit the temperatures achieved in laboratories like CAL, which means the orbiting facility is regularly the coldest known spot in the universe.

What’s So Cool About NASA’s Cold Atom Lab?

NASA's Cold Atom Laboratory on the International Space Station is regularly the coldest known spot in the universe. But why are scientists producing clouds of atoms a fraction of a degree above absolute zero? And why do they need to do it in space? Quantum physics, of course.

Seven months after its May 21, 2018, launch to the space station from NASA's Wallops Flight Facility in Virginia, CAL is producing ultracold atoms daily. Five teams of scientists will carry out experiments on CAL during its first year, and three experiments are already underway.

Image above: The Cold Atom Laboratory (CAL) consists of two standardized containers that will be installed on the International Space Station. The larger container holds CAL's physics package, or the compartment where CAL will produce clouds of ultracold atoms. Image Credit: NASA/JPL-Caltech.

Why cool atoms to such an extreme low? Room-temperature atoms typically zip around like hyperactive hummingbirds, but ultracold atoms move much slower than even a snail. Specifics vary, but ultracold atoms can be more than 200,000 times slower than room-temperature atoms. This opens up new ways to study atoms as well as new ways to use them for investigations of other physical phenomena. CAL's primary science objective is to conduct fundamental physics research - to try to understand the workings of nature at the most fundamental levels.

"With CAL we're starting to get a really thorough understanding of how the atoms behave in microgravity, how to manipulate them, how the system is different than the ones we use on Earth," said Rob Thompson, a cold atom physicist at NASA's Jet Propulsion Laboratory in Pasadena, California, and the mission scientist for CAL. "This is all knowledge that is going to build a foundation for what I hope is a long future of cold atom science in space."

Image above: The Cold Atom Laboratory (CAL), packaged in a protective layer, is loaded onto a Northrop Grumman (formerly Orbital ATK) Cygnus spacecraft for its trip to the International Space Station. The facility launched in May 2018 from NASA's Wallops Flight Facility in Virginia. Image Credits: NASA/Northrop Grumman.

Laboratories on Earth can produce ultracold atoms, but on the ground, gravity pulls on the chilled atom clouds and they fall quickly, giving scientists only fractions of a second to observe them. Magnetic fields can be used to "trap" the atoms and hold them still, but that restricts their natural movement. In microgravity, the cold atom clouds float for much longer, giving scientists an extended view of their behavior.

The process to create the cold atom clouds starts with lasers that begin to lower the temperature by slowing the atoms down. Radio waves cut away the warmest members of the group, further lowering the average temperature. Finally, the atoms are released from a magnetic trap and allowed to expand. This causes a drop in pressure that, in turn, naturally causes another drop in the cloud's temperature (the same phenomenon that causes a can of compressed air to feel cold after use). In space, the cloud has longer to expand and thus reach even lower temperatures than what can be achieved on Earth - down to about one ten billionth of a degree above absolute zero, perhaps even lower.

Image above: Astronaut Ricky Arnold assists with the installation of NASA's Cold Atom Laboratory (CAL) on the International Space Station. Image Credits: NASA/JPL-Caltech.

Ultracold atom facilities on Earth typically occupy an entire room, and in most, the hardware is left exposed so that scientists can adjust the apparatus if need be. Building a cold atom laboratory for space posed several design challenges, some of which change the fundamental nature of these facilities. First, there was the matter of size: CAL flew to the station in two pieces - a metal box a little larger than a minifridge and a second one about the size of a carry-on suitcase. Second, CAL was designed to be operated remotely from Earth, so it was built as a fully enclosed facility.

CAL also features a number of technologies that have never been flown in space before, such as specialized vacuum cells that contain the atoms, which have to be sealed so tightly that almost no stray atoms can leak in. The lab needed to be able to withstand the shaking of launch and extreme forces experienced during the flight to the space station. It took the teams several years to develop unique hardware that could meet the precise needs for cooling atoms in space.

Image above: Cold Atom Laboratory (CAL) physicist David Aveline works in the CAL test bed, which is a replica of the CAL facility that stays on Earth. Scientists use the test bed to run tests and understand what is happening inside CAL while it is operating on the International Space Station. Image Credits: NASA/JPL-Caltech.

"Several parts of the system required redesigning, and some parts broke in ways we'd never seen before," said Robert Shotwell, chief engineer for JPL's Astronomy, Physics and Space Technology Directorate and CAL project manager. "The facility had to be completely torn apart and reassembled three times."

All the hard work and problem solving since the mission's inception in 2012 turned the CAL team's vision into reality this past May. CAL team members talked via live video with astronauts Ricky Arnold and Drew Feustel aboard the International Space Station for the installation of the Cold Atom Laboratory, the second ultracold atom facility ever operated in space, the first to reach Earth orbit and the first to remain in space for more than a few minutes. Along the way, CAL has also met the minimum requirements NASA set to deem the mission a success and is providing a unique tool for probing nature's mysteries.

Image above: Shown here is the "physics package" inside the Cold Atom Laboratory (CAL), where ultracold clouds of atoms called Bose-Einstein condensates are produced. Image Credits: NASA/JPL-Caltech.

Designed and built at JPL, CAL is sponsored by the International Space Station Program at NASA's Johnson Space Center in Houston, and the Space Life and Physical Sciences Research and Applications (SLPSRA) Division of NASA's Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington.

Related links:

Cold Atom Laboratory (CAL):

More information on CAL is online at:

Images (mentioned), Text, Credits: NASA/JPL/Calla Cofield.


jeudi 20 décembre 2018

Faint Glow Within Galaxy Clusters Illuminates Dark Matter

NASA - Hubble Space Telescope patch.

Dec. 20, 2018

A new look at Hubble images of galaxies could be a step toward illuminating the elusive nature of dark matter, the unobservable material that makes up the majority of the universe, according to a study published online today in the Monthly Notices of the Royal Astronomical Society.

Utilizing Hubble's past observations of six massive galaxy clusters in the Frontier Fields program, astronomers demonstrated that intracluster light — the diffuse glow between galaxies in a cluster — traces the path of dark matter, illuminating its distribution more accurately than existing methods that observe X-ray light.

Image above: Hubble's powerful sensitivity and resolution captures a soft blue haze, called intracluster light, among innumerable galaxies in the Abell S1063 cluster. The stars producing this glow have been thrown out from their galaxies. These stars now live solitary lives, no longer part of a galaxy but aligning themselves with the gravity of the overall cluster. Astronomers have found that intracluster light's association with a map of mass distribution in the cluster's overall gravitational field makes it a good indicator of how invisible dark matter is distributed in the cluster. Image Credits: NASA, ESA and M. Montes (University of New South Wales).

Intracluster light is the byproduct of interactions between galaxies that disrupt their structures; in the chaos, individual stars are thrown free of their gravitational moorings in their home galaxy to realign themselves with the gravity map of the overall cluster. This is also where the vast majority of dark matter resides. X-ray light indicates where groups of galaxies are colliding, but not the underlying structure of the cluster. This makes it a less precise tracer of dark matter.

"The reason that intracluster light is such an excellent tracer of dark matter in a galaxy cluster is that both the dark matter and these stars forming the intracluster light are free-floating on the gravitational potential of the cluster itself — so they are following exactly the same gravity," said Mireia Montes of the University of New South Wales in Sydney, Australia, who is co-author of the study. "We have found a new way to see the location where the dark matter should be, because you are tracing exactly the same gravitational potential. We can illuminate, with a very faint glow, the position of dark matter."

Montes also highlights that not only is the method accurate, but it is more efficient in that it utilizes only deep imaging, rather than the more complex, time-intensive techniques of spectroscopy. This means more clusters and objects in space can be studied in less time — meaning more potential evidence of what dark matter consists of and how it behaves.

"This method puts us in the position to characterize, in a statistical way, the ultimate nature of dark matter," Montes said.

Image above: Amid the bright light of its member galaxies, the galaxy cluster MACS J0416.1-2403 also emits a soft glow of intracluster light, produced by stars that are not part of any individual galaxy. These stars were scattered throughout the cluster long ago, when their home galaxies were torn apart by the cluster's gravitational forces. The homeless stars eventually aligned themselves with the gravity of the overall cluster. Hubble's unique sensitivity and resolution captures the faint light and uses it to trace the location of invisible dark matter, which dominates the cluster's gravitational field. Image Credits: NASA, ESA and M. Montes (University of New South Wales).

"The idea for the study was sparked while looking at the pristine Hubble Frontier Field images," said study co-author Ignacio Trujillo of the Canary Islands Institute of Astronomy in Tenerife, Spain, who along with Montes had studied intracluster light for years. "The Hubble Frontier Fields showed intracluster light in unprecedented clarity. The images were inspiring," Trujillo said. "Still, I did not expect the results to be so precise. The implications for future space-based research are very exciting."

"The astronomers used the Modified Hausdorff Distance (MHD), a metric used in shape matching, to measure the similarities between the contours of the intracluster light and the contours of the different mass maps of the clusters, which are provided as part of the data from the Hubble Frontier Fields project, housed in the Mikulski Archive for Space Telescopes (MAST). The MHD is a measure of how far two subsets are from each other. The smaller the value of MHD, the more similar the two point sets are. This analysis showed that the intracluster light distribution seen in the Hubble Frontier Fields images matched the mass distribution of the six galaxy clusters better than did X-ray emission, as derived from archived observations from Chandra X-ray Observatory's Advanced CCD Imaging Spectrometer (ACIS).

Beyond this initial study, Montes and Trujillo see multiple opportunities to expand their research. To start, they would like to increase the radius of observation in the original six clusters, to see if the degree of tracing accuracy holds up. Another important test of their method will be observation and analysis of additional galaxy clusters by more research teams, to add to the data set and confirm their findings.

The astronomers also look forward to the application of the same techniques with future powerful space-based telescopes like the James Webb Space Telescope and WFIRST, which will have even more sensitive instruments for resolving faint intracluster light in the distant universe.

Trujillo would like to test scaling down the method from massive galaxy clusters to single galaxies. "It would be fantastic to do this at galactic scales, for example exploring the stellar halos. In principal the same idea should work; the stars that surround the galaxy as a result of the merging activity should also be following the gravitational potential of the galaxy, illuminating the location and distribution of dark matter."

Hubble Space Telescope (HST). Animation Credits: NASA/ESA

The Hubble Frontier Fields program was a deep imaging initiative designed to utilize the natural magnifying glass of galaxy clusters' gravity to see the extremely distant galaxies beyond them, and thereby gain insight into the early (distant) universe and the evolution of galaxies since that time. In that study the diffuse intracluster light was an annoyance, partially obscuring the distant galaxies beyond. However, that faint glow could end up shedding significant light on one of astronomy's great mysteries: the nature of dark matter.

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

Related links:

Dark Energy and Dark Matter:

Hubble Space Telescope (HST):

Images (mentioned), Animation (mentioned), Text, Credits: NASA/Karl Hille/Space Telescope Science Institute/Leah Ramsay/Ray Villard/University of New South Wales, Sydney, Australia/Mireia Montes.


A Bold Step: Apollo 8 Sends First Human Flight Beyond Earth

NASA - Apollo 8 Mission patch.

Dec. 20, 2018

"Apollo 8. You are Go for TLI."

Image above: Frank Borman, Jim Lovell and Bill Anders looked back after leaving Earth orbit for the Moon. This view extends the northern hemisphere to the southern tip of South America. Nearly all of South America is covered by clouds. Image Credits: NASA.

With these cryptic words spoken on Dec. 21, 1968, NASA's Mission Control gave the crew of Apollo 8 approval for TLI -- trans-lunar injection -- permission to become the first humans to leave Earth orbit. Their destination, 234,000 miles away, was the Moon.

After Apollo 7 successfully flew the program's command-service module in Earth orbit two months earlier, Lt. Gen. Sam Phillips, NASA's Apollo Program director, announced a bold next step.

"By going into lunar orbit, we make an early flight demonstration of the design mission of the Saturn V, the Apollo spacecraft, and understand its operation in translunar space," he said.

Image above: The Apollo 8 crew stands in foreground as their Saturn V launch vehicle rolls out of the Vehicle Assembly Building at NASA's Kennedy Space Center on Oct. 9, 1968. The Apollo 8 crew consists of, from the left, commander Frank Borman, command module pilot Jim Lovell and lunar module pilot Bill Anders. Image Credit: NASA.

Apollo 8 commander Frank Borman was a U.S. Air Force colonel and test pilot. A member of NASA's second group of astronauts, he was command pilot for the Gemini VII mission, Dec. 4-18, 1965.

Command module pilot on Apollo 8 was Jim Lovell, a naval aviator and test pilot, also from the second astronaut group. He flew with Borman on Gemini VII and commanded Gemini XII, Nov. 11-15, 1966.

A member of the third astronaut class, Bill Anders was a major in the U.S. Air Force and a jet fighter pilot. For Apollo 8, he was designated the lunar module (LM) pilot, although there was no LM on this flight.

The Apollo 8 crew was the first to launch atop the powerful Saturn V rocket, lifting off from Launch Complex 39A at NASA's Kennedy Space Center in Florida.

After liftoff, Kennedy's chief of Operations, George Page, described processing and launch preparations as "fantastic."

Image above: The Apollo 8 crew became the first astronauts to fly the 363-foot-tall Saturn V rocket, lifting off Dec. 21, 1968 with 7.5 million pounds of thrust. The vehicle has just cleared the tower at Launch Complex 39A at NASA's Kennedy Space Center in Florida. Image Credit: NASA.

"The countdown came off exceedingly well," he said.

For TLI, two hours and 50 minutes after liftoff, the Saturn V's third stage fired, propelling the spacecraft to 24,208 MPH.

"The crew is traveling faster than man has ever flown before," said NASA Public Affairs commentator Paul Haney.

Now on a trajectory to the Moon, they separated their Apollo spacecraft from the Saturn V third stage, turned around and saw a striking view.

"We have a beautiful view of Florida now," Lovell said. "We can see the Cape (Canaveral), just the point. And at the same time, we can see Africa. West Africa is beautiful. I can also see Gibraltar at the same time I'm looking at Florida."

Image above: This photograph of Earth was taken from the Apollo 8 spacecraft while it was leaving Earth orbit. Most of the southeastern United States and the Caribbean Sea area, the U.S. coastline can be seen. The Bahamas and the islands of Cuba, in the Caribbean are visible in the lower left. Image Credit: NASA.

As Borman, Lovell and Anders approached the Moon early on Christmas Eve, Apollo 8 and Mission Control prepared for the vital firing of the spacecraft's service propulsion system (SPS) engine. That will place them in lunar orbit.

But that crucial maneuver would take place behind the Moon while out of contact with Earth. As the crew was about to travel out of touch, spacecraft communicator Jerry Carr, a fellow astronaut, passed along reassuring words.

"Apollo 8, one minute to LOS (loss of signal)," he said. "All systems Go. Safe journey, guys."

"We'll see you on the other side," Lovell said.

The SPS engine would have to fire for a little over four minutes. All the flight controllers could do was wait.

And people around the world watched . . .  and waited . . .  for 37 minutes and 32 seconds.

Then data began streaming to consoles in Mission Control.

"We've got it," Haney announced, "Apollo 8 now in lunar orbit! There is a cheer in this room."

Image above: "I think the thing that impressed me the most was the lunar sunrises and sunsets," said Apollo 8 astronaut Bill Anders as he described his impressions of the Moon from about 60 miles. "These in particular bring out the stark nature of the terrain, and the long shadows really bring out the relief." This oblique photograph looks northwest into the Sea of Tranquility, the site where Apollo 11 would land seven months later. Image Credit: NASA.

Carr asked, "What does the 'ole Moon look like from 60 miles?"

"Like dirty beach sand with lots of footprints in it," Anders said.

Over the next 20 hours, Apollo 8 orbited the Moon 10 times at an altitude of about 60 miles. The crew took detailed images of the lunar surface that would help flight planners select landing sites for upcoming missions to land on the Moon.

During a television broadcast seen by viewers around the world, the crew related what they were seeing.

"My own impression is that it's a vast, lonely, forbidding-type existence, or expanse of nothing, that looks rather like clouds and clouds of pumice stone," Borman said.

Lovell expressed similar thoughts.

"The vast loneliness up here of the Moon is awe inspiring, and it makes you realize just what you have back there on Earth," he said. "The Earth from here is a grand oasis in the big vastness of space."

Animation above: “Earthrise,” as photographed by the Apollo 8 crew on Christmas Eve 1968, laid over NASA's 2013 recreation using Lunar Reconnaissance Orbiter (LRO) data. Animation Credit: NASA.

During the final orbit, time came for a 3 minute, 23 second trans-Earth Injection burn of the SPS engine to propel Apollo 8 for the trip home. It happened early on Christmas morning and, again, while Mission Control waited and Apollo 8 was behind the Moon.

"Please be informed there is a Santa Claus," said Lovell, announcing that firing worked as planned.

 Apollo 8 Captures “Earthrise” – Dec. 24, 1968. Image Credit: NASA

Just before sunrise on Dec. 27, 1968, Apollo 8 splashed down in the Pacific Ocean near the recovery aircraft carrier, the USS Yorktown.

After Borman, Lovell and Anders were safely aboard the ship, Dr. Thomas Paine, then acting NASA administrator, described the mission as "a true pioneering effort" opening the way for greater achievements.

"We are at the onset of a program of space flight that will extend through many generations," he said. "We're looking forward to the days we will be manning space stations, conducting lunar explorations and blazing trails out to the planets."

Image above: This computer-generated visualization depicts the Apollo 8 spacecraft in orbit around the Moon, with Earth rising over the horizon. Image Credits: NASA Goddard Scientific Visualization Studio/Ernie Wright.

Apollo 8 Crew Captures Iconic Earthrise Image

The year 1968 was one of the most turbulent in history. War was raging in Vietnam, Rev. Martin Luther King Jr. and Sen. Robert Kennedy were assassinated and the Cold War included the race to the Moon.

But at Christmastime a half-century ago, millions around the world paused to follow the flight of Apollo 8. For the first time, humans left Earth for a distant destination.

The mission was a key step toward meeting President John F. Kennedy's goal of "landing a man on the Moon and returning him safely to Earth" by the end of the decade.

Image above: The United States Postal Service issued a commemorative stamp celebrating Apollo 8, the first human flight to the Moon. The design is based on the photograph taken by astronaut Bill Anders on Dec. 24, 1968. The inscription recalls the crew reading the opening verses of the Bible's book of Genesis during a live television broadcast. Image Credits: U.S. Postal Service.

In addition to gaining the first close-up views of the lunar surface, the cameras of Frank Borman, Jim Lovell and Bill Anders also were focused back toward Earth.

While Borman maneuvered the Apollo spacecraft during the fourth lunar orbit, Anders was taking pictures of the surface. He then glanced at the Moon's horizon.

"Oh, my god, look at that picture over there," Anders said. "Here's the Earth coming up. Wow, is that pretty."

No Apollo 8 photograph was more stunning than his image that has come to be known as "Earthrise."

On May 5, 1969, the United States Postal Service issued a commemorative stamp celebrating the first human flight to the Moon. The design is based on Anders' Christmas Eve picture of the lunar surface with the Earth 234,000 miles away.

Anders later put the photography of Apollo in perspective.

"We came all this way to explore the Moon," he said, "and the most important thing is that we discovered the Earth."

Credit: NASA

NASA Marks the Legacy of Apollo

From October 2018 through December 2022, NASA is marking the 50th anniversary of the 11 Apollo missions that included landing a dozen Americans on the Moon between July 1969 and December 1972. Today, NASA is working to return astronauts to the Moon to test technologies and techniques for the next giant leaps – challenging missions to Mars and other destinations in deep space.

Related links:


Apollo 8:

NASA History:

For more information about NASA’s plan for the future, visit:

Images (mentioned), Text, Credits: NASA's Kennedy Space Center, by Bob Granath.

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NASA Telescopes Take a Close Look at the Brightest Comet of 2018

NASA Goddard Space Flight Center logo.

Dec. 20, 2018

As the brilliant comet 46P/Wirtanen streaked across the sky, NASA telescopes caught it on camera from multiple angles.

NASA’s Hubble Space Telescope photographed comet 46P/Wirtanen on Dec. 13, when the comet was 7.4 million miles (12 million kilometers) from Earth. In this visible light image, the comet’s nucleus is hidden in the center of a fuzzy glow from the comet’s coma. The coma is a cloud of gas and dust that the comet has ejected during its pass through the inner solar system due to heating from the Sun. To make this composite image, the color blue was applied to high-resolution grayscale exposures acquired from the spacecraft’s WFC3 instrument.

Image above: Credits: NASA, ESA, and D. Bodewits (Auburn University), and J.-Y. Li (Planetary Science Institute).

The inner part of a comet’s coma is normally not accessible from Earth. The close fly-by of comet 46P/Wirtanen allowed astronomers to study it in detail. They combined the unique capabilities of Hubble, NASA’s Chandra X-ray Observatory, and the Neil Gehrels Swift Observatory to study how gases are released from the nucleus, what the comet’s ices are composed of, and how gas in the coma is chemically altered by sunlight and solar radiation.

NASA’s Stratospheric Observatory for Infrared Astronomy, SOFIA, took this image of the comet on Dec. 16 and 17 when the aircraft was flying at 40,000 feet.

Image above: Credits: NASA/SOFIA.

Comets and asteroids may be the source of Earth’s water. SOFIA is studying the chemical fingerprints of different types of hydrogen in the comet’s water, which will help us learn about the origins and history of water in the solar system — including Earth’s oceans.

The SOFIA image was taken with the telescope's visible light guide camera, using an orange filter to indicate the intensity of light relative to other objects. SOFIA's observations using infrared light to study the comet's water are now under analysis.

Comet 46P/Wirtanen made its closest approach to Earth on Dec. 16, when it passed just over 7 million miles (11 million kilometers) from our planet, about 30 times farther away than the Moon. Although its close approach is valuable for making science observations from Earth, and it is the brightest comet of 2018, 46P/Wirtanen is only barely visible to the unaided eye even where the sky is very dark. It is best viewed through binoculars or a telescope.

Backyard observers can currently find the comet near the constellation Taurus though with the challenge of added light from the Moon, but it will continue to be viewable in the weeks to come. Finder charts and other information are available at the Comet Wirtanen Observing Campaign website.

Comet 46P/Wirtanen orbits the Sun once every 5.4 years, much quicker than the 75-year orbit of the more famous Comet Halley. Most of its passes through the inner solar system are much farther from Earth, making this year’s display particularly notable.

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

SOFIA is a Boeing 747SP jetliner modified to carry a 106-inch diameter telescope. It is a joint project of NASA and the German Aerospace Center, DLR. NASA’s Ames Research Center in California’s Silicon Valley manages the SOFIA program, science and mission operations in cooperation with the Universities Space Research Association headquartered in Columbia, Maryland, and the German SOFIA Institute (DSI) at the University of Stuttgart. The aircraft is maintained and operated from NASA’s Armstrong Flight Research Center Hangar 703, in Palmdale, California.

Related links:

Comet Wirtanen Observing Campaign website:

Hubble Space Telescope (HST):


Goddard Space Flight Center:

Images (mentioned), Text, Credits: NASA/Rob Garner.