samedi 7 mars 2020

SpaceX to send tourists to ISS

SpaceX logo.

March 7, 2020

Elon Musk's company wants to send three tourists to the International Space Station in 2021.

The Space X Crew Dragon capsule that will transport tourists to the ISS

The American space company SpaceX announced Thursday a partnership intended to send next year three tourists to the International Space Station (ISS), which has not been done for more than ten years. Elon Musk's company has signed an agreement with Axiom Space to give it seats on board its Crew Dragon capsule.

Scheduled for the second half of 2021, this trip "will mark a turning point in the universalization of access to space", welcomed the boss of Axiom Space, Michael Suffredini, without revealing the price.

Each launch of its Falcon 9 rocket costs Space X about $ 60 million (56.73 million francs). Adding the cost of building the capsule, we can estimate that the ticket for the ISS will amount to several tens of millions of dollars.

Last trip in 2009

Eight space tourists have already made a trip to the international station in the Russian Soyuz rockets. The first was Dennis Tito, who paid $ 20 million (18.91 million francs) in 2001 for an eight-day stay at the ISS. The most recent was the founder of Cirque du Soleil, Guy Laliberté, in 2009.

SpaceX had announced in February another partnership, with the company Space Adventures, to send four tourists in orbit to an altitude never before reached by a private flight. This mission is also scheduled for the end of 2021, but should probably not take place until 2022.

Founder of Cirque du Soleil, Guy Laliberté, in 2009

Virgin Galactic (Richard Branson) and Blue Origin (Jeff Bezos) are also involved in space tourism. They are currently developing vessels capable of sending private passengers, for a few minutes, just over the border of space (80 or 100 km depending on the definitions chosen by each company), for 250,000 dollars (236,000 francs) or more in the case of Virgin.


What SpaceX offers is much more ambitious with its reusable Falcon 9 rocket, the same one that sends satellites into space and will send astronauts to the ISS.

International Space Station (ISS)

Boeing is also developing a vehicle, Nasa, Starliner, to join the ISS. Boeing wants private passengers to travel there in the future, but the development of Starliner is hampered by major software problems that almost caused its loss during an unmanned test mission in December.

Note from the Editor:

It has never been a good idea to send tourists (multi-millionaires) to a space laboratory at the expense of real professional astronauts (Missions Specialists) who have years of training and skills, who are on the waiting list and who pass their turn by a tourist, it is not only not normal but in addition these installations are paid with the taxes of the taxpayers of the partner countries, the space station is a scientific orbiting laboratory, not an amusement park.


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


SpaceX Dragon Heads to Space Station with NASA Science, Cargo

SpaceX - Dragon CRS-20 Mission patch.

March 7, 2020

Image above: A SpaceX Dragon cargo spacecraft launches on a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida at 11:50 p.m. EST March 6, 2020. Dragon will deliver more than 4,300 pounds of NASA cargo and science investigations to the International Space Station, including a new science facility scheduled to be installed to the outside of the station during a spacewalk this spring. Image Credit: NASA Television.

A SpaceX Dragon cargo spacecraft is on its way to the International Space Station after launching at 11:50 p.m. EST Friday. Dragon will deliver more than 4,300 pounds of NASA cargo and science investigations, including a new science facility scheduled to be installed to the outside of the station during a spacewalk this spring.

The spacecraft launched on a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station in Florida and is scheduled to arrive at the orbital outpost on Monday, March 9. Coverage of the spacecraft’s approach and arrival at the space station will begin at 5:30 a.m. EDT on NASA Television and the agency’s website.

SpaceX CRS-20 launch & Falcon 9 first stage landing

Dragon will join three other spacecraft currently at the station. When it arrives, NASA Flight Engineer Andrew Morgan will grapple Dragon, backed up by NASA’s Jessica Meir. Coverage of robotic installation to the Earth-facing port of the Harmony module will begin at 8:30 a.m.

Dragon is scheduled to remain at the space station until April 9, when the spacecraft will return to Earth with research and cargo.

This delivery, SpaceX’s 20th cargo flight to the space station under NASA’s Commercial Resupply Services contract, will support dozens of new and existing investigations. NASA’s research and development work aboard the space station contributes to the agency’s deep space exploration plans, including future Moon and Mars missions.

Here are details about some of the scientific investigations Dragon is delivering:

New Facility Outside the Space Station

The Bartolomeo facility, created by ESA (European Space Agency) and Airbus, attaches to the exterior of the European Columbus Module. Designed to provide new scientific opportunities on the outside of the space station for commercial and institutional users, the facility offers unobstructed views both toward Earth and into space. Potential applications include Earth observation, robotics, material science and astrophysics.

Studying the Human Intestine On a Chip

Organ-Chips as a Platform for Studying Effects of Space on Human Enteric Physiology (Gut on Chip) examines the effect of microgravity and other space-related stress factors on biotechnology company Emulate’s human innervated Intestine-Chip (hiIC). This Organ-Chip device enables the study of organ physiology and diseases in a laboratory setting. It allows for automated maintenance, including imaging, sampling, and storage on orbit and data downlink for molecular analysis on Earth.

Growing Human Heart Cells

Generation of Cardiomyocytes From Human Induced Pluripotent Stem Cell-derived Cardiac Progenitors Expanded in Microgravity (MVP Cell-03) examines whether microgravity increases the production of heart cells from human-induced pluripotent stem cells (hiPSCs). The investigation induces stem cells to generate heart precursor cells and cultures those cells on the space station to analyze and compare with cultures grown on Earth.

These are just a few of the hundreds of investigations providing opportunities for U.S. government agencies, private industry, and academic and research institutions to conduct microgravity research that leads to new technologies, medical treatments and products that improve life on Earth. Conducting science aboard the orbiting laboratory will help us learn how to keep astronauts healthy during long-duration space travel and demonstrate technologies for future human and robotic exploration beyond low-Earth orbit to the Moon and Mars.

For almost 20 years, humans have lived and worked continuously aboard the International Space Station, advancing scientific knowledge and demonstrating new technologies, making research breakthroughs not possible on Earth that will enable long-duration human and robotic exploration into deep space. As a global endeavor, 239 people from 19 countries have visited the unique microgravity laboratory that has hosted more than 2,800 research investigations from researchers in 108 countries.

For more information about the International Space Station, its research, and crew, visit:

Related articles:

Bartolomeo heading for space to join Columbus

SpaceX CRS-20 Launch Targeted for March 6

Improving Shoes, Showers, 3D Printing: Research Launching to the Space Station

Space Life and Physical Sciences Research and Applications SpaceX-20 Experiments and Payloads

Related links:

NASA Television:

Commercial Resupply Services:


Gut on Chip:

MVP Cell-03:

International Space Station (ISS):

Image (mentioned), Video, Text, Credits: NASA/Karen Northon/Kathryn Hambleton​/JSC/Courtney Beasley/NASA TV/SciNews.

Best regards,

vendredi 6 mars 2020

Space Station Science Highlights: Week of March 2, 2020

ISS - Expedition 62 Mission patch.

March 6, 2020

The week of March 2, crew members aboard the International Space Station conducted scientific investigations that included studies of radiation exposure and the effects of microgravity on gene expression. The crew also prepared for arrival of a SpaceX Dragon resupply ship scheduled to launch on March 6 and arrive at the station March 9 with new scientific investigations.

Image above: In this image taken from the International Space Station as it orbited 263 miles above Sudan, the Nile River winds northward toward the Mediterranean Sea, with the Red Sea visible in the upper right. Image Credit: NASA.

Now in its 20th year of continuous human presence, the space station provides a platform for long-duration research in microgravity and for learning to live and work in space. Experience gained on the orbiting lab supports Artemis, NASA’s program to go forward to the Moon and on to Mars.

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

Mapping space station radiation exposure

International Space Station (ISS). Animation Credit: NASA

Dose Distribution Inside the International Space Station - 3D (DOSIS-3D), sponsored by the ESA (European Space Agency, uses active and passive detectors to determine radiation doses inside the space station. Crew members are continually exposed to varying levels of radiation that can be harmful to their health. The investigation creates a three-dimensional radiation map covering all sections inside the craft based on data from this investigation and other JAXA and NASA monitoring devices. Crew members removed one of the detectors, the Dosimetric Telescope (DOSTEL-1) in preparation for its return on the SpaceX-20 resupply craft.

Higher resolution Earth imaging

The crew performed troubleshooting for the Hyperspectral Imager Suite (HISUI), a next-generation space-based Earth imaging system. HISUI is a follow-on of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), a Japan Aerospace Exploration Agency (JAXA) remote sensing instrument operating aboard NASA’s Terra spacecraft. ASTER collects data in the visible to shortwave infrared spectrum. HISUI has higher spectral resolution, which provides the capability to measure surface reflectance more precisely. Every material on the Earth’s surface, from rocks and vegetation to human-made objects, reflects a unique spectrum of light and can be identified by the characteristics of that spectrum.

The inflight operations of HISUI include calibration, mission planning, and data acquisition and analysis that enable researchers to verify the usefulness of the hardware in various applications.

Genes in partial gravity

Image above: NASA astronaut Andrew Morgan works on the Mouse Habitat Unit, used by the JAXA Mouse Habitat Unit-5 (MHU-5) investigation into the effects of partial gravity on mice. Image Credit: NASA.

The crew prepared mouse habitat cage units (HCU) for the JAXA Mouse Habitat Unit-5 (MHU-5) investigation, which arrives on the SpaceX-20 resupply mission. MHU-5 examines the effects of partial gravity on mice using the HCUs developed by the Japanese Aerospace Exploration Agency (JAXA) and installed in the Centrifuge-equipped Biological Experiment Facility-L (CBEF-L). The investigation analyzes any alterations in gene expression caused by partial gravity and their possible effects on development of germ cells, which carry genetic information and expression to subsequent generations. Better understanding on the gravitational biology of mammals could provide fundamental knowledge of how partial gravity affects crew members on future exploration missions to the Moon, Mars and beyond.

Sintering in microgravity

Image above: Example of liquid phase sintered tungsten alloy. The MSL SCA-GEDS-German experiment examines underlying scientific principles of liquid phase sintering in Earth’s gravity and microgravity. Image Credit: San Diego State University.

The NASA Sample Cartridge Assembly-Gravitational Effects on Distortion in Sintering (MSL SCA-GEDS-German) experiment examines underlying scientific principles in order to forecast density, size, shape and properties of liquid phase sintered bodies in Earth’s gravity and microgravity. Liquid phase sintering is a manufacturing process using heat to consolidate solid grains with a wetting liquid.

A number of fields employ this practice, including metal cutting tools, armor piercing projectiles, automotive engine connecting rods and self-lubricating bearings. The process could provide a way to make and repair materials on future space missions and even enable the use of lunar regolith or dust to fabricate structures on the Moon or use of metal powder to make replacement parts for extraterrestrial exploration.

Ground teams initiated processing of a Sample Assemblies Cartridge (SCA) for the investigation during the week. The samples will return on the SpaceX-20 cargo resupply vessel.

Other investigations on which the crew performed work:

Animation above: NASA astronaut Jessica Meir works on the OsteoOmics 2 investigation in the Life Sciences Glovebox. This investigation looks at molecular and metabolic changes in osteoblasts, cells in the body that form bone, in real and simulated microgravity. Animation Credit: NASA.

- OsteoOmics investigates the molecular and metabolic changes that occur in osteoblasts, cells in the body that form bone, in real and simulated microgravity.

- BioFabrication Facility (BFF) tests the printing of human organs and tissues in microgravity, a first step toward manufacturing entire human organs in space using refined biological 3D printing techniques.

- Sally Ride EarthKAM allows students to control a camera remotely to take photographs of coastlines, mountain ranges and other interesting features and phenomena from space. The EarthKAM team posts the images online for the public and participating classrooms to view.

- Standard Measures captures an ongoing, optimized set of measures from crew members to characterize how their bodies adapt to living in space. Researchers use these measures to create a data repository for high-level monitoring of the effectiveness of countermeasures and better interpretation of health and performance outcomes.

- Food Acceptability examines the effect of repetitive consumption of the food currently available during spaceflight. “Menu fatigue” resulting from a limited choice of foods over time may contribute to the loss of body mass often experienced by crew members, potentially affecting astronaut health, especially as mission length increases.

Space to Ground: Making Space: 03/06/2020

Related article:

NASA TV Coverage Set for SpaceX’s Next Space Station Resupply Mission

Related links:

Expedition 62:







ISS National Lab:

Spot the Station:

Space Station Research and Technology:

International Space Station (ISS):

Images (mentioned), Animations (mentioned), Text, Credits: NASA/Michael Johnson/John Love, Lead Increment Scientist Expedition 62.

Best regards,

Hubble Spies Galactic Traffic Jam

NASA - Hubble Space Telescope patch.

March 6, 2020

The barred spiral galaxy NGC 3887, seen here as viewed by the Wide Field Camera 3 aboard the NASA/ESA Hubble Space Telescope, lies over 60 million light-years away from us in the southern constellation of Crater (the Cup). It was discovered on Dec. 31, 1785, by astronomer William Herschel.

Its orientation to us, while not exactly face-on, allows us to see NGC 3887’s spiral arms and central bulge in detail, making it an ideal target for studying a spiral galaxy’s winding arms and the stars within them.

The very existence of spiral arms was for a long time a problem for astronomers. The arms emanate from a spinning core and should therefore become wound up ever more tightly, causing them to eventually disappear after a (cosmologically) short amount of time. It was only in the 1960s that astronomers came up with the solution to this winding problem; rather than behaving like rigid structures, spiral arms are in fact areas of greater density in a galaxy’s disk, with dynamics similar to those of a traffic jam. The density of cars moving through a traffic jam increases at the center of the jam, where they move more slowly. Spiral arms function in a similar way; as gas and dust move through the density waves, they become compressed and linger before moving out of them again.

Hubble Space Telescope (HST)

For more information about Hubble, visit:

Text Credits: ESA (European Space Agency)/NASA/Rob Garner/Image, Animation, Credits: ESA/Hubble & NASA, P. Erwin et al.

Best regards,

NASA Satellite Offers Urban Carbon Dioxide Insights

NASA - Orbiting Carbon Observatory-2 (OCO-2) logo.

March 6, 2020

Using data from NASA's Orbiting Carbon Observatory-2, researchers found links between the population density of cities and how much carbon dioxide they produce per person.

Image above: NASA Satellite Offers Urban Carbon Dioxide Insights NASA's Orbiting Carbon Observatory-2 (OCO-2) measures the amount of carbon dioxide in the atmosphere over areas like Las Vegas, Nevada, to help researchers better characterize the sources and sinks of the greenhouse gas. Image Credits: Bert Kaufmann/CC BY-SA.

A new NASA/university study of carbon dioxide emissions for 20 major cities around the world provides the first direct, satellite-based evidence that as a city's population density increases, the carbon dioxide it emits per person declines, with some notable exceptions. The study also demonstrates how satellite measurements of this powerful greenhouse gas can give fast-growing cities new tools to track carbon dioxide emissions and assess the impact of policy changes and infrastructure improvements on their energy efficiency.

Cities account for more than 70% of global carbon dioxide emissions associated with energy production, and rapid, ongoing urbanization is increasing their number and size. But some densely populated cities emit more carbon dioxide per capita than others.

To better understand why, atmospheric scientists Dien Wu and John Lin of the University of Utah in Salt Lake City teamed with colleagues at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and the University of Michigan in Ann Arbor. They calculated per capita carbon dioxide emissions for 20 urban areas on several continents using recently available carbon dioxide estimates from NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite, managed by the agency's Jet Propulsion Laboratory in Pasadena, California. Cities spanning a range of population densities were selected based on the quality and quantity of OCO-2 data available for them. Cities with minimal vegetation were preferred because plants can absorb and emit carbon dioxide, complicating the interpretation of the measurements. Two U.S. cities were included: Las Vegas and Phoenix.

Many scientists and policy makers have assumed the best way to estimate and understand differences in carbon dioxide emissions in major cities is to employ a "bottom-up" approach, compiling an inventory of fossil fuel emissions produced by industrial facilities, farms, road transport and power plants. The bottom-up method was the only feasible approach before remote-sensing data sets became available. This approach can provide estimates of emissions by fuel type (coal, oil, natural gas) and sector (power generation, transportation, manufacturing) but can miss some emissions, especially in rapidly developing urban areas.

But for this study, researchers instead employed a "top-down" approach to inventory emissions, using satellite-derived estimates of the amount of carbon dioxide present in the air above an urban area as the satellite flies overhead.

"Other people have used fuel statistics, the number of miles driven by a person or how big people's houses are to calculate per capita emissions," Lin said. "We're looking down from space to actually measure the carbon dioxide concentration over a city."

Published Feb. 20 in the journal Environmental Research Letters, the study found that cities with higher population densities generally have lower per capita carbon dioxide emissions, in line with previous bottom-up studies based on emissions inventories. But the satellite data provided new insights.

"Our motivating question was essentially: When people live in denser cities, do they emit less carbon dioxide? The general answer from our analysis suggests, yes, emissions from denser cities are lower," said Eric Kort, principal investigator and associate professor of climate and space sciences and engineering at the University of Michigan. "It isn't a complete picture, since we only see local direct emissions, but our study does provide an alternative direct observational assessment that was entirely missing before."

The Density Factor, and Exceptions

Scientists have hypothesized that more densely-populated urban areas generally emit less carbon dioxide per person because they are more energy efficient: That is, less energy per person is needed in these areas because of factors like the use of public transportation and the efficient heating and cooling of multi-family dwellings. Satellite data can improve our understanding of this relationship because they describe the combined emissions from all sources. This information can be incorporated with more source-specific, bottom-up inventories to help city managers plan for more energy-efficient growth and develop better estimates of future carbon dioxide emissions.

Image above: A spatial map of the amount of carbon dioxide (CO2) present in columns of the atmosphere below NASA's Orbiting Carbon Observatory-2 (OCO-2) satellite as it flew over Las Vegas on Feb. 8, 2018. Warmer colors over the city center indicate higher amounts of carbon dioxide. Image Credits: NASA/JPL-Caltech/University of Utah.

The OCO-2 data show that not all densely-populated urban areas have lower per capita emissions, however. Cities with major power generation facilities, such as Yinchuan, China, and Johannesburg, had higher emissions than what their population density would otherwise suggest.

"The satellite detects the carbon dioxide plume at the power plant, not at the city that actually uses the power," Lin said.

"Some cities don't produce as much carbon dioxide, given their population density, but they consume goods and services that would give rise to carbon dioxide emissions elsewhere," Wu added.

Another exception to the higher population density/lower emissions observation is affluence. A wealthy urban area, like Phoenix, produces more emissions per capita than a developing city like Hyderabad, India, which has a similar population density. The researchers speculate that Phoenix's higher per capita emissions are due to factors such as higher rates of driving and larger, better air-conditioned homes.

Looking Ahead

The researchers stress there's much more to be learned about urban carbon dioxide emissions. They believe new data from OCO-2's successor, OCO-3 - which launched to the International Space Station last year - along with future space-based carbon dioxide-observing missions, may shed light on potential solutions to mitigating cities' carbon emissions.

"Many people are interested in carbon dioxide emissions from large cities," Wu said. "Additionally, there are a few places with high emissions that aren't necessarily related to population. Satellites can detect and quantify emissions from those locations around the globe."

Animation above: This animation shows the Orbiting Carbon Observatory-2, the first NASA spacecraft dedicated to studying carbon dioxide in Earth's atmosphere. Animation Credits: NASA/JPL-Caltech.

Launched in 2014, OCO-2 gathers global measurements of atmospheric carbon dioxide - the principal human-produced driver of climate change - with the resolution, precision and coverage needed to understand how it moves through the Earth system and how it changes over time. From its vantage point in space, OCO-2 makes roughly 100,000 measurements of atmospheric carbon dioxide over the globe every day. JPL manages OCO-2 for NASA's Science Mission Directorate, Washington.

While OCO-2 wasn't optimized to monitor carbon emissions from cities or power plants, it can observe these targets if it flies directly overhead or if the observatory is reoriented to point in their direction. In contrast, OCO-3, which has been collecting daily measurements of carbon dioxide since last summer, features an agile mirror-pointing system that allows it to capture "snapshot maps." In a matter of minutes, it can create detailed mini-maps of carbon dioxide over areas of interest as small as an individual power plant to a large urban area up to 2,300 square miles (6,400 square kilometers), such as the Los Angeles Basin, something that would take OCO-2 several days to do.

For more information on OCO-2 and OCO-3, visit:

Environmental Research Letters:

Images (mentioned), Animation (mentioned), Text, Credits: NASA/JPL/Jane Lee/University of Utah/Paul Gabrielsen.


jeudi 5 mars 2020

New ESO Study Evaluates Impact of Satellite Constellations on Astronomical Observations

ESO - European Southern Observatory logo.

5 March 2020

Areas of the sky most affected by satellite constellations

Astronomers have recently raised concerns about the impact of satellite mega-constellations on scientific research. To better understand the effect these constellations could have on astronomical observations, ESO commissioned a scientific study of their impact, focusing on observations with ESO telescopes in the visible and infrared but also considering other observatories. The study, which considers a total of 18 representative satellite constellations under development by SpaceX, Amazon, OneWeb and others, together amounting to over 26 thousand satellites [1], has now been accepted for publication in Astronomy & Astrophysics.

The study finds that large telescopes like ESO's Very Large Telescope (VLT) and ESO's upcoming Extremely Large Telescope (ELT) will be "moderately affected" by the constellations under development. The effect is more pronounced for long exposures (of about 1000 s), up to 3% of which could be ruined during twilight, the time between dawn and sunrise and between sunset and dusk. Shorter exposures would be less impacted, with fewer than 0.5% of observations of this type affected. Observations conducted at other times during the night would also be less affected, as the satellites would be in the shadow of the Earth and therefore not illuminated. Depending on the science case, the impacts could be lessened by making changes to the operating schedules of ESO telescopes, though these changes come at a cost [2]. On the industry side, an effective step to mitigate impacts would be to darken the satellites. 

Schematic showing the satellites that would be visible at a given time and place 

The study also finds that the greatest impact could be on wide-field surveys, in particular those done with large telescopes. For example, up to 30% to 50% of exposures with the US National Science Foundation's Vera C. Rubin Observatory (not an ESO facility) would be "severely affected”, depending on the time of year, the time of night, and the simplifying assumptions of the study. Mitigation techniques that could be applied on ESO telescopes would not work for this observatory although other strategies are being actively explored. Further studies are required to fully understand the scientific implications of this loss of observational data and complexities in their analysis. Wide-field survey telescopes like the Rubin Observatory can scan large parts of the sky quickly, making them crucial to spot short-lived phenomena like supernovae or potentially dangerous asteroids. Because of their unique capability to generate very large data sets and to find observation targets for many other observatories, astronomy communities and funding agencies in Europe and elsewhere have ranked wide-field survey telescopes as a top priority for future developments in astronomy.

Professional and amateur astronomers alike have also raised concerns about how satellite mega-constellations could impact the pristine views of the night sky. The study shows that about 1600 satellites from the constellations will be above the horizon of an observatory at mid-latitude, most of which will be low in the sky — within 30 degrees of the horizon. Above this — the part of the sky where most astronomical observations take place — there will be about 250 constellation satellites at any given time. While they are all illuminated by the Sun at sunset and sunrise, more and more get into the shadow of the Earth toward the middle of the night. The ESO study assumes a brightness for all of these satellites. With this assumption, up to about 100 satellites could be bright enough to be visible with the naked eye during twilight hours, about 10 of which would be higher than 30 degrees of elevation. All these numbers plummet as the night gets darker and the satellites fall into the shadow of the Earth. Overall, these new satellite constellations would about double the number of satellites visible in the night sky to the naked eye above 30 degrees [3].

These numbers do not include the trains of satellites visible immediately after launch. Whilst spectacular and bright, they are short lived and visible only briefly after sunset or before sunrise, and — at any given time — only from a very limited area on Earth. 

The ESO study uses simplifications and assumptions to obtain conservative estimates of the effects, which may be smaller in reality than calculated in the paper. More sophisticated modelling will be necessary to more precisely quantify the actual impacts. While the focus is on ESO telescopes, the results apply to similar non-ESO telescopes that also operate in the visible and infrared, with similar instrumentation and science cases.

The sky above the ELT site

Satellite constellations will also have an impact on radio, millimetre and submillimetre observatories, including the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder Experiment (APEX). This impact will be considered in further studies.

ESO, together with other observatories, the International Astronomical Union (IAU), the American Astronomical Society (AAS), the UK Royal Astronomical Society (RAS), and other societies, is taking measures to raise the awareness of this issue in global fora such as the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and the European Committee on Radio Astronomy Frequencies (CRAF). This is being done while exploring with the space companies practical solutions that can safeguard the large-scale investments made in cutting-edge ground-based astronomy facilities. ESO supports the development of regulatory frameworks that will ultimately ensure the harmonious coexistence of highly promising technological advancements in low Earth orbit with the conditions that enable humankind to continue its observation and understanding of the Universe.


[1] Many of the parameters characterising satellite constellations, including the total number of satellites, are changing on a frequent basis. The study assumes 26,000 constellation satellites in total will be orbiting the Earth, but this number could be higher.

[2] Examples of mitigation measures include: computing the position of the satellites to avoid observing where one will pass; closing the telescope shutter at the precise moment when a satellite crosses the field of view; and constraining observations to areas of the sky that are in Earth’s shadow, where satellites are not illuminated by the sun. These methods, however, are not suitable for all science cases.

[3] It is estimated that about 34 000 objects greater than 10 cm in size are currently orbiting the Earth. Of these, about 5500 are satellites, including about 2300 functional ones. The remainder are space debris, including rocket upper stages and satellite launch adapters. About 2000 of these objects are above the horizon at any given place at any one time. During twilight hours, about 5–10 of them are illuminated by the Sun and bright enough to be seen with the naked eye.

More information:

The study, “On the impact of Satellite Constellations on Astronomical Observations with ESO Telescopes in the Visible and Infrared Domains”, by O. Hainaut and A. Williams, will appear in Astronomy and Astrophysics (


Science paper:

ESO announcement "Satellite Constellations and their Impact on Astronomy":

IAU press release "Understanding the Impact of Satellite Constellations on Astronomy":

AAS post "AAS Works to Mitigate Impact of Satellite Constellations on Ground-Based Observing":

Rubin Observatory Legacy Survey of Space and Time (LSST) "Impact on Optical Astronomy of LEO Satellite Constellations":

Images, Text, Credits: ESO/Bárbara Ferreira/Andrew Williams/Garching bei München/Olivier R. Hainaut/ESO/Y. Beletsky/L. Calçada/M. Zamani.

Best regards,

Bartolomeo heading for space to join Columbus

ESA & DLR - Columbus Module patch.

March 5, 2020

Shiny Columbus during spacewalk

Europe’s external commercial experiment-hosting facility is headed for the International Space Station on Saturday morning, hitching a ride on the SpaceX Dragon 20 cargo vessel. Named after Christopher Columbus’ younger brother, Bartolomeo will provide room for experiments from commercial and institutional organisations that want to capitalise on access to space as well as experiments from ESA, NASA and more.

Bartolomeo is built and operated by Airbus but hosted by ESA on the International Space Station. The facility will be installed on the outside of the European Columbus laboratory with a clear view of Earth.

Unpacking Bartolomeo

The facility will fly to space in the external cargo hold of the Dragon and will be moved into position on Columbus by the Station’s robotic arm.

Previous spacewalks prepared Columbus’ hull to receive the new host facility by adapting support pins to which Bartolomeo will connect. Two weeks ago, NASA astronaut Jessica Meir set up hardware inside the Station that will provide a connection with the new facility.

Installing cables for Bartolomeo inside Columbus

Astronauts will perform a spacewalk to install Bartolomeo in the next few months, together with a new terminal called ColKa that will upgrade the European space laboratory.

Bartolomeo before flight

“Bartolomeo is the first European external commercial facility on the International Space Station, offering a high-speed data feed and a unique view of Earth and deep space,” says ESA’s Bernhard Hufenbach, leader of the strategy and innovation team for human and robotic exploration. “The versatile Bartolomeo service provides easy access to space at competitive pricing and will expand the use of Europe’s assets on the International Space Station for many years to come.”

Airbus-built Bartolomeo Platform for the International Space Station

The first experiment for Bartolomeo is a ‘Langmuir probe’ technology demonstrator that offers quicker and more precise measurements of electrons in plasma. The data from the Langmuir probe will increase our understanding of how plasma in the atmosphere distorts signals from satellites as they reach Earth. This in turn will help develop a space weather forecast system that predicts when signals used in global navigation satellite systems will be distorted.

More cargo

The SpaceX launch is set for liftoff from Cape Canaveral in Florida, USA, at 05:49 CET (04:49 GMT) on Saturday.


Other cargo from Europe for the International Space Station includes parts for the Materials Science Laboratory, radiation dosimeters and medical equipment for the Myotones experiment that monitors the tone, stiffness and elasticity of astronauts’ muscles.

Watch the launch live through NASA television:


Human and Robotic Exploration:

International Space Station (ISS):

Images, Video, Text, Credits: ESA/Airbus/NASA.


The dark dunes of Mars: Moreux crater

ESA - Mars Express Mission patch.

March 5, 2020

The dark dunes of Moreux crater

Known for its wide swathes of rippling, textured, gently sloping dunes, the Terra Sabaea region on Mars is home to many fascinating geological features – including the prominent Moreux crater, the star of a new image from ESA’s Mars Express.

The Moreux crater on Mars showcases numerous intriguing geological processes and features. It sits at the northern edge of Terra Sabaea, a large area of the Red Planet that is speckled with impact craters and covered in glacial flows, dunes, fretted terrain and intricate ridge networks.

Mars Express

When compared to other impact craters on both Mars and Earth, Moreux crater appears a little misshapen and messy – the result of ongoing erosion over martian history. Its egg-shaped rim is broken up, its dark walls are ridged, rippled and mottled, and its centre features a prominent clustered ‘peak’, created as material from the crater floor rebounded and rose upwards following the initial impact.

The topography of Moreux crater

It is difficult to get a sense of scale when viewing this peak from orbit, but Moreux crater’s central peak is sizeable, reaching around two kilometres in height. The crater itself is roughly three kilometres deep, and spans 135 kilometres from edge to edge.

The range of colours featured in images like this one, taken by the High Resolution Stereo Camera on Mars Express, reveals much about the composition of a particular region, material or feature.

In the case of Moreux crater, the colour differences are stark: while the surrounding material is visible in hues of butterscotch and caramel, the crater’s walls are dark, resembling a smudged ring of ash or charcoal. Dark brown and black dunes cover the crater floor, while the peak remains a pale yellow-orange. Dark, prominent ejecta, comprising material flung outwards during the crater-forming collision, spread outwards from the crater rim, discolouring and encroaching upon the lighter surrounding terrain.

Perspective view of Moreux crater

This varied colour palette reflects an equally varied geological composition. The dunes within and around the crater are thought to contain sandy material rich in pyroxene and olivine: rock-forming minerals that are mafic (containing magnesium and iron) and characterised by their typically dark appearance.

Martian winds are also thought to have swept and gathered fine, basaltic, volcanic sand and ash into and around the crater. Basaltic rock is commonplace on both Mars and other celestial bodies. It is a key component of the maria, or seas, on the Moon, for instance, and causes them to appear visibly and notably darker than the lunar highlands.

Moreux crater on Mars (perspective view)

Many of the features, such as dunes and flows, surrounding the central peak and southern region of Moreux crater (to the left of the image) appear to have been formed by ice. This is thought to have occurred in the form of substantial episodes of glacial activity over the past few million years.

Many other features show signs of wind erosion, or having been formed via wind-related processes – most notably, the dunes covering the crater floor. These dunes are largely sickle-shaped (barchanoid), and reveal much about wind direction within and across the crater.

Moreux crater in context

From the orientation of the dunes, scientists have inferred a complex system of prevailing winds, likely influenced by the topography of the crater itself. Dunes to the north and east of the central peak are largely influenced by winds coming from the northeast, while dunes sitting west of the park are controlled by winds from the northwest.

Moreux Crater in 3D

These cross-cutting winds create an interesting and unique dune morphology within Moreux crater, adding to the feature’s intrigue.

Mars Express:

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

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NASA's Deep Space Antenna Upgrades to Affect Voyager Communications

NASA - Deep Space Network (DSN) 50 Years logo.

March 5, 2020

The antenna enhancements will improve future spacecraft communications, but during the upgrades, Voyager 2 will not be able to receive new commands from Earth.

Image above: DSS43 is a 70-meter-wide (230-feet-wide) radio antenna at the Deep Space Network's Canberra facility in Australia. It is the only antenna that can send commands to the Voyager 2 spacecraft. Image Credits: NASA/Canberra Deep Space Communication Complex.

Starting in early March, NASA's Voyager 2 will quietly coast through interstellar space without receiving commands from Earth. That's because the Voyager's primary means of communication, the Deep Space Network's 70-meter-wide (230-feet-wide) radio antenna in Canberra, Australia, will be undergoing critical upgrades for about 11 months. During this time, the Voyager team will still be able to receive science data from Voyager 2 on its mission to explore the outermost edge of the Sun's domain and beyond.

About the size of a 20-story office building, the dish has been in service for 48 years. Some parts of the 70-meter antenna, including the transmitters that send commands to various spacecraft, are 40 years old and increasingly unreliable. The Deep Space Network (DSN) upgrades are planned to start now that Voyager 2 has returned to normal operations, after accidentally overdrawing its power supply and automatically turning off its science instruments in January.

The network operates 24 hours a day, 365 days a year and is spread over three sites around the world, in California, Spain and Australia. This allows navigators to communicate with spacecraft at the Moon and beyond at all times during Earth's rotation. Voyager 2, which launched in 1977, is currently more than 11 billion miles (17 billion kilometers) from Earth. It is flying in a downward direction relative to Earth's orbital plane, where it can be seen only from the southern hemisphere and thus can communicate only with the Australian site.

Moreover, a special S-band transmitter is required to send commands to Voyager 2 - one both powerful enough to reach interstellar space and on a frequency that can communicate with Voyager's dated technology. The Canberra 70-meter antenna (called "DSS43") is the only such antenna in the southern hemisphere. As the equipment in the antenna ages, the risk of unplanned outages will increase, which adds more risk to the Voyager mission. The planned upgrades will not only reduce that risk, but will also add state-of-the art technology upgrades that will benefit future missions.

"Obviously, the 11 months of repairs puts more constraints on the other DSN sites," said Jeff Berner, Deep Space Network's chief engineer. "But the advantage is that when we come back, the Canberra antenna will be much more reliable."

The repairs will benefit far more than Voyager 2, including future missions like the Mars 2020 rover and Moon to Mars exploration efforts. The network will play a critical role in ensuring communication and navigation support for both the precursor Moon and Mars missions and the crewed Artemis missions. "The maintenance is needed to support the missions that NASA is developing and launching in the future, as well as supporting the missions that are operating right now," said Suzanne Dodd, Voyager project manager and JPL Director for the Interplanetary Network.

The three Canberra 34-meter (111-foot) antennas can be configured to listen to Voyager 2's signal; they just won't be able to transmit commands. In the meantime, said Dodd, the Voyager team will put the spacecraft into a quiescent state, which will still allow it to send back science data during the 11-month downtime.

"We put the spacecraft back into a state where it will be just fine, assuming that everything goes normally with it during the time that the antenna is down," said Dodd. "If things don't go normally - which is always a possibility, especially with an aging spacecraft - then the onboard fault protection that's there can handle the situation."

Berner says the work on the 70-meter antenna is like bringing an old car into the shop: There's never a good time to do it, but it will make the car much more dependable if you do.

The work on the Canberra DSN station is expected to be completed by January 2021. The DSN is managed by NASA's Jet Propulsion Laboratory for the agency's Human Exploration and Operations' Space Communication and Navigation program.

Related articles:

Update: Voyager 2 Resumes Taking Science Data

Voyager 2 Engineers Working to Restore Normal Operations

Related links:

Mars 2020 rover:

Moon to Mars:

Artemis missions:


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


mercredi 4 mars 2020

3D Bioprinter, Bone Research Continues Ahead of Dragon Launch

ISS - Expedition 62 Mission patch.

March 4, 2020

The Expedition 62 crew is continuing its human research activities midweek aboard the International Space Station. The SpaceX Dragon resupply mission is also due to launch Friday with over 5,600 pounds of science, supplies and hardware.

A 3D bioprinter that manufactures human tissue in space is being tested this week aboard the orbiting lab. NASA astronaut Jessica Meir ran test prints Wednesday morning without using cells. Afterward, she cleaned and swapped syringes on the organ-manufacturing device. The BioFabrication Facility seeks to overcome gravity’s detrimental effects on manufacturing human organs on Earth.

Image above: Expedition 62 Flight Engineer Jessica Meir works with research hardware to support the OsteoOmics-02 bone investigation. Image Credit: NASA.

NASA Flight Engineer Andrew Morgan serviced bone cell samples in support of the OsteoOmics-02 investigation. He changed the media that nourishes the cells that scientists are observing to understand how microgravity affects bones. Results may improve therapies for Earth ailments such as osteoporosis.

Both astronauts continue readying the space station for a space delivery due Monday at 7 a.m. EDT aboard the Dragon space freighter. Dragon will launch Friday at 11:50 p.m. atop the Falcon 9 rocket from Kennedy Space Center.

International Space Station (ISS). Animation Credit: NASA

Meir and Morgan are familiarizing themselves with the new space cargo and making room aboard the station to stow everything. The Harmony module, where Dragon will be installed, is also being outfitted with a variety of support gear to enable the resupply ship’s month-long stay.

Over in the Russian segment of the station, Commander Oleg Skripochka checked power and life support systems in the Zarya module. In the afternoon, he activated an experiment that is studying the relationship between the Earth’s geologic and atmospheric phenomena. Finally, the veteran cosmonaut participated in a study that assesses the station’s environment to facilitate microgravity research.

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

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The Shape of Watering Plants in Space

ISS - International Space Station logo.

March 4, 2020

The challenge: getting water to behave the way it does on Earth while in a microgravity environment. A collaboration between NASA, Techshot, Inc., and the Tupperware Brands Corporation is working to get the solution just right.

Image above: Canadian Space Agency astronaut David Saint-Jacques is photographed performing a reservoir fill on the Veggie Ponds facility in the Columbus module of the International Space Station in 2019. The primary goal of the hardware validation test was to demonstrate plant growth in a newly developed plant growing system, Passive Orbital Nutrient Delivery System (PONDS). Image Credit: NASA.

For nearly 20 years, people have lived and worked continuously aboard the International Space Station, performing science to enable deep space exploration for NASA’s Artemis lunar exploration program and future human missions to Mars and to benefit people on Earth. The space station is about the size of a six-bedroom house, and it is a busy laboratory studying everything from fundamental science to practical applications, such as growing food in space.

In the current method of growing plants in space in the station’s Veggie growth chamber, astronauts water plants with a syringe, pushing it into containers called plant pillows, which hold a limited amount of water. This works well for leafy greens like lettuce, but for larger plants that require more water, NASA needed an alternate system.

Image above: An assembled version of the PONDS-03 unit is photographed inside the Space Life Sciences Laboratory at NASA’s Kennedy Space Center in Florida. Twelve PONDS units are launching to the International Space Station on SpaceX’s 20th Commercial Resupply Services mission for their third technology demonstration in an effort to study the growth of lettuce in an entirely passive growth system. Photo credit: Techshot, Inc. Image Credit: Techshot, Inc.

A collaboration between NASA, Techshot, Inc., and the Tupperware Brands Corporation introduced a plant growth unit called PONDS, short for Passive Orbital Nutrient Delivery System. The PONDS units are an entirely passive system – meaning no electricity, no pumps and no moving parts – and the basic concept involves using a free-standing reservoir of water that plants can draw from when needed, cutting down on time astronauts would spend watering plants during the growth interval. The reservoir holds 400 ml – or about 13.5 ounces – of water, allowing astronauts to go a week or more before needing to water smaller plants again, or every couple of days for full-size plants.

“PONDS has kind of become the story of Goldilocks,” said Dave Reed, Florida operations director for Techshot. “The first time we tested in microgravity, too much water was delivered to the seeds. The second time, too little water. And the third time we hope is going to be just right. We’re in the fine-tuning phase now, and we’re excited to see this all come to fruition.”

Initially sent to the space station in 2018 and then again in 2019 after undergoing some design and operational modifications, PONDS is returning to the orbiting laboratory for further testing. Twelve PONDS units are being sent to the station for their third technology demonstration, titled VEG-PONDS-03, on SpaceX’s 20th Commercial Resupply Services mission. In addition to carrying this experiment, the cargo Dragon will deliver additional science investigations, including research of particle foam manufacturing, water droplet formation and the human intestine.

Image above: Jeff Richards, an employee with the Laboratory Support Services and Operations (LASSO) contract at NASA’s Kennedy Space Center in Florida, assembles PONDS hardware components inside the Space Life Sciences Laboratory. Twelve PONDS units are launching to the International Space Station on SpaceX’s 20th Commercial Resupply Services mission for their third technology demonstration in an effort to study the growth of lettuce in an entirely passive growth system. Image Credit: Techshot, Inc.

“You have to have this give and take, and a bit of trial and error; and I think part of that was seen in the first two PONDS experiments, with some things working and others not working,” said Howard Levine, creator of the initial PONDS concept and chief scientist of NASA’s Utilization and Life Sciences Office at the agency’s Kennedy Space Center in Florida.

When astronauts travel to the space station, all their food, clothes, and anything else they may need is delivered to them through regular cargo resupply missions. Once the design of PONDS is perfected, astronauts will be able to use this method to grow fresh vegetables and perhaps even fruits in space, something that crew members will rely on to supplement their diet as they venture deeper into space. “The longer the duration of the mission, [resupply] becomes less and less viable, and you want to be able to actually grow your food,” said Levine.

All 12 of the PONDS units being delivered will contain red romaine lettuce seeds and grow for 28 days inside the space station’s two Veggie growth chambers, and at harvest, crew members will have the opportunity to eat the lettuce they grew. At the end of the experiment, half of the PONDS units will be returned to Kennedy for engineers to evaluate. Six of the units have undergone design changes under the leadership of Levine, while the other six were given to Techshot and Tupperware to evolve.

“We’re used to designing and perfecting products to help prevent food from going to waste. When we were approached for this experiment a few years ago, we knew it was a great opportunity to take our long history of food conservation and apply it to the conditions in space,” said David Kusuma, Tupperware’s vice president of research and design. “Adapting and engineering design to fit the unique conditions in orbit has been an exciting and educational journey for us. Helping NASA and Techshot open doors for astronauts of the future to germinate, grow and harvest fresh fruits and vegetables in space is something we’re quite proud of.”

Image above: All 12 PONDS units are photographed inside the Space Life Sciences Laboratory at NASA’s Kennedy Space Center in Florida following assembly. The PONDS units are launching to the International Space Station on SpaceX’s 20th Commercial Resupply Services mission for their third technology demonstration in an effort to study the growth of lettuce in an entirely passive growth system. Image Credit: Techshot, Inc.

Some modifications to Techshot and Tupperware’s units include using narrower, skinnier wicks made of a different material to hold the plant seeds in place; adding a structure to the top of the units to keep sponges treated to repel water flat against the top surface to provide oxygen to the plants’ roots; and taking a piece of that same sponge and running it down the length of the flower pot-like root zone, providing a column of air going all the way to the bottom to ensure the plant roots are getting enough air. Levine’s units have larger and wider wicks for the plant seeds, and they will contain blocks of oasis foam – a material that has been used many times before in space to grow plants – near the wicks at the top to draw excess water away from the sprouting seeds. By exploring these design changes, NASA, Techshot and Tupperware hope to find the perfect balance for controlling how water behaves in space.

“Even people who are fluids experts – and we’ve worked with some of the best that NASA knows – tell us they’re constantly surprised by what fluids do in low gravity,” said Reed. “So, a lot of thought has gone into this design. Things that would seem arbitrary when you look at them are absolutely not. We have engineered the heck out of this system to get it to where it is today.”

The Space Life and Physical Sciences Research and Applications Division (SLPSRA) of NASA’s Human Exploration and Operations Mission Directorate at NASA Headquarters in Washington is sponsoring the Veg-PONDS-03 investigation as part of its mission to conduct research that enables human spaceflight exploration.

Related links:


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Humans in Space:

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


NASA's Curiosity Mars Rover Snaps Its Highest-Resolution Panorama Yet

NASA - Mars Science Laboratory (MSL) patch.

March 4, 2020

Image above: NASA's Curiosity rover captured its highest-resolution panorama of the Martian surface between Nov. 24 and Dec. 1, 2019. Image Credits: NASA/JPL-Caltech/MSSS.

NASA's Curiosity rover has captured its highest-resolution panorama yet of the Martian surface. Composed of more than 1,000 images taken during the 2019 Thanksgiving holiday and carefully assembled over the ensuing months, the composite contains 1.8 billion pixels of Martian landscape. The rover's Mast Camera, or Mastcam, used its telephoto lens to produce the panorama; meanwhile, it relied on its medium-angle lens to produce a lower-resolution, nearly 650-million-pixel panorama that includes the rover's deck and robotic arm.

Image above: Along with an almost 1.8-billion-pixel panorama that doesn't feature the rover, NASA's Curiosity captured a 650-million-pixel panorama that features the rover itself. Image Credits: NASA/JPL-Caltech/MSSS.

Both panoramas showcase "Glen Torridon," a region on the side of Mount Sharp that Curiosity is exploring. They were taken between Nov. 24 and Dec. 1, when the mission team was out for the Thanksgiving holiday. Sitting still with few tasks to do while awaiting the team to return and provide its next commands, the rover had a rare chance to image its surroundings from the same vantage point several days in a row. (Look closer: A special tool allows viewers to zoom into this panorama.)

It required more than 6 1/2 hours over the four days for Curiosity to capture the individual shots. Mastcam operators programmed the complex task list, which included pointing the rover's mast and making sure the images were in focus. To ensure consistent lighting, they confined imaging to between noon and 2 p.m. local Mars time each day.

Curiosity Mars Rover Snaps 1.8 Billion-Pixel Panorama (narrated video)

Video above: NASA Curiosity Project Scientist Ashwin Vasavada guides this tour of the rover's view of the Martian surface. Image Credits: NASA/JPL-Caltech/MSSS.

"While many on our team were at home enjoying turkey, Curiosity produced this feast for the eyes," said Ashwin Vasavada, Curiosity's project scientist at NASA's Jet Propulsion Laboratory, which leads the Curiosity rover mission. "This is the first time during the mission we've dedicated our operations to a stereo 360-degree panorama."

In 2013, Curiosity produced a 1.3-billion-pixel panorama using both Mastcam cameras; its black-and-white Navigation Cameras, or Navcams, provided images of the rover itself. Imaging specialists carefully assemble Mars panoramas by creating mosaics composed of individual pictures and blending their edges to create a seamless look.

Mars Science Laboratory (MSL) or Curiosity rover. Animation Credits: NASA/JPL

Malin Space Science Systems in San Diego built and operates Curiosity's Mastcam. JPL, a division of Caltech in Pasadena, manages the project for NASA's Science Mission Directorate in Washington and built the Navigation Cameras and the rover.

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Images (mentioned), Animation (mentioned), Video (mentioned), Text, Credits: NASA/Tony Greicius/Alana Johnson/JPL/Andrew Good.