Setting the Clock on a Stellar Explosion

 

NASA - Chandra X-ray Observatory patch.

Sep 12, 2022

While astronomers have seen the debris from scores of exploded stars in the Milky Way and nearby galaxies, it is often difficult to determine the timeline of the star’s demise. By studying the spectacular remains of a supernova in a neighboring galaxy using NASA telescopes, a team of astronomers has found enough clues to help wind back the clock.

The supernova remnant called SNR 0519-69.0 (SNR 0519 for short) is the debris from an explosion of a white dwarf star. After reaching a critical mass, either by pulling matter from a companion star or merging with another white dwarf, the star underwent a thermonuclear explosion and was destroyed. Scientists use this type of supernova, called a Type Ia, for a wide range of scientific studies ranging from studies of thermonuclear explosions to measuring distances to galaxies across billions of light-years.

SNR 0519 is located in the Large Magellanic Cloud, a small galaxy 160,000 light-years from Earth. This composite image shows X-ray data from NASA’s Chandra X-ray Observatory and optical data from NASA’s Hubble Space Telescope. X-rays from SNR 0519 with low, medium and high energies are shown in green, blue, and purple respectively, with some of these colors overlapping to appear white. Optical data shows the perimeter of the remnant in red and stars around the remnant in white.

Astronomers combined the data from Chandra and Hubble with data from NASA’s retired Spitzer Space telescope to determine how long ago the star in SNR 0519 exploded and learn about the environment the supernova occurred in. This data provides scientists a chance to “rewind” the movie of the stellar evolution that has played out since and figure out when it got started.

The researchers compared Hubble images from 2010, 2011, and 2020 to measure the speeds of material in the blast wave from the explosion, which range from about 3.8 million to 5.5 million miles (9 million kilometers) per hour. If the speed was toward the upper end of those estimated speeds, the astronomers determined that light from the explosion would have reached Earth about 670 years ago, or during the Hundred Years’ War between England and France and the height of the Ming dynasty in China.

However, it’s likely that the material has slowed down since the initial explosion and that the explosion happened more recently than 670 years ago. The Chandra and Spitzer data provide clues that this is the case. Astronomers found the brightest regions in X-rays of the remnant are where the slowest-moving material is located, and no X-ray emission is associated with the fastest-moving material.

These results imply that some of the blast wave has crashed into dense gas around the remnant, causing it to slow down as it traveled. Astronomers may use additional observations with Hubble to determine more precisely when the time of the star’s demise should truly be set.

Chandra X-ray Observatory

A paper describing these results was published in the August issue of The Astrophysical Journal, and a preprint is available here. The authors of the paper are Brian Williams (NASA’s Goddard Space Flight Center (GSFC) in Greenbelt, Maryland); Parviz Ghavamian (Towson University, Towson, Maryland); Ivo Seitenzahl (University of New South Wales, Australian Defence Force Academy, Canberra, Australia); Stephen Reynolds (North Carolina State University (NCSU), Raleigh, NC); Kazimierz Borkowski (North Carolina State University, Raleigh, NC) and Robert Petre (GSFC). NASA's Marshall Space Flight Center manages the Chandra program. The Smithsonian Astrophysical Observatory's Chandra X-ray Center controls science operations from Cambridge, Massachusetts, and flight operations from Burlington, Massachusetts.

Read more from NASA's Chandra X-ray Observatory: https://chandra.harvard.edu/photo/2022/snr0519/

For more Chandra images, multimedia and related materials, visit: http://www.nasa.gov/chandra

Image credit: X-ray: NASA/CXC/GSFC/B. J. Williams et al.; Optical: NASA/ESA/STScI/Animation Credits: NASA/CXC/Text Credits: NASA/Lee Mohon.

Greetings, Orbiter.ch

New Shepard NS-23 launch anomaly

 

Blue Origin - New Shepard NS-23 Mission patch.

Sept. 12, 2022

New Shepard flight profile

Blue Origin’s New Shepard reusable launch system has suffered an anomaly after being launched from the Launch Site One in West Texas, on 12 September 2022, at 14:26 UTC (09:26 CDT). The New Shepard capsule carried 34 payloads.

New Shepard launch anomaly (NS-23)

Two payloads were placed on the exterior of the New Shepard booster for ambient exposure to the space environment. NS-23 was the ninth mission, launch and landing, for this New Shepard launch vehicle (NS3).

Anomaly on the booster (main engine), yellow flames

During today’s flight, the capsule escape system successfully separated the capsule from the booster. The booster impacted the ground. There are no reported injuries; all personnel have been accounted for.

Ignition of the capsule ejection system rockets

Booster failure on today’s uncrewed flight. Escape system performed as designed.

New Shepard configuration & description

We're responding to an issue this morning at our Launch Site One location in West Texas. This was a payload mission with no astronauts on board. The capsule escape system functioned as designed. More information to come as it is available.

Blue Origin: https://www.blueorigin.com/
 
Images, Video, Text, Credits: Blue Origin/SciNews/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

CLEP - Chang’e-6 to return samples from the far side of the Moon

 

CLEP - China Lunar Exploration Program logo.

Sept. 12, 2022

Chang’e-6 to return samples from the far side of the Moon

According to the China National Space Administration (CNSA), the Chang’e-6 mission will return samples from the far side of the Moon.

Chang’e-6 to return samples from the far side of the Moon

According to Liu Jizhong (director of the Lunar Exploration and Space Program Center), the Chang’e-6 (嫦娥六) probe is almost completed and the mission is expected to be launched in 2024.

For more information about China National Space Administration (CNSA), visit: http://www.cnsa.gov.cn/

Image, Video, Text, Credits: China National Space Administration (CNSA)/China Media Group(CMG)/China Central Television (CCTV)/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Solar Orbiter solves magnetic switchback mystery

 

ESA / NASA - Solar Orbiter Mission patch.

Sept. 12, 2022

With data from its closest pass of the Sun yet, the ESA/NASA Solar Orbiter spacecraft has found compelling clues as to the origin of magnetic switchbacks, and points towards how their physical formation mechanism might help accelerate the solar wind.

Zooming in on a solar switchback

Solar Orbiter has made the first ever remote sensing observation consistent with a magnetic phenomenon called a solar switchback – sudden and large deflections of the solar wind’s magnetic field. The new observation provides a full view of the structure, in this case confirming it has an S-shaped character, as predicted. Furthermore, the global perspective provided by the Solar Orbiter data indicates that these rapidly changing magnetic fields can have their origin near the surface of the Sun.

Switchback in action

While a number of spacecraft have flown through these puzzling regions before, in situ data only allow for a measurement at a single point and time. Consequently, the structure and shape of the switchback has to be inferred from plasma and magnetic field properties measured at one point.

When the German-US Helios 1 and 2 spacecraft flew close to the Sun in the mid 1970s, both probes recorded sudden reversals of the Sun’s magnetic field. These mysterious reversals were always abrupt and always temporary, lasting from a few seconds to a number of hours before the magnetic field switched back to its original direction.

These magnetic structures were also probed at much larger distances from the Sun by the Ulysses spacecraft in the late 1990s. Instead of a third the Earth’s orbital radius from the Sun, where the Helios missions made their closest pass, Ulysses operated mostly beyond the Earth’s orbit.

How a solar switchback is formed

Their number rose dramatically with the arrival of NASA’s Parker Solar Probe in 2018. This clearly indicated that the sudden magnetic field reversals are more numerous close to the Sun, and led to the suggestion that they were caused by S-shaped kinks in the magnetic field. This puzzling behaviour earned the phenomenon the name of switchbacks. A number of ideas were proposed as to how these might form.

On 25 March 2022, Solar Orbiter was just a day away from a close pass of the Sun – bringing it within the orbit of planet Mercury – and its Metis instrument was taking data. Metis blocks out the bright glare of light from the Sun’s surface and takes pictures of the Sun’s outer atmosphere, known as the corona. The particles in the corona are electrically charged and follow the Sun’s magnetic field lines out into space. The electrically charged particles themselves are called a plasma.

Capturing a solar switchback

At around 20:39 UT, Metis recorded an image of the solar corona that showed a distorted S-shaped kink in the coronal plasma. To Daniele Telloni, National Institute for Astrophysics - Astrophysical Observatory of Torino, Italy, it looked suspiciously like a solar switchback.

Comparing the Metis image, which had been taken in visible light, with a concurrent image taken by Solar Orbiter’s Extreme Ultraviolet Imager (EUI) instrument, he saw that the candidate switchback was taking place above an active region catalogued as AR 12972. Active regions are associated with sunspots and magnetic activity. Further analysis of the Metis data showed that the speed of the plasma above this region was very slow, as would be expected from an active region that has yet to release its stored energy.

Daniele instantly thought this resembled a generating mechanism for the switchbacks proposed by Prof. Gary Zank, University of Alabama in Huntsville, USA. The theory looked at the way different magnetic regions near the surface of the Sun interact with each other.

Creating a solar switchback

Close to the Sun, and especially above active regions, there are open and closed magnetic field lines. The closed lines are loops of magnetism that arch up into the solar atmosphere before curving round and disappearing back into the Sun. Very little plasma can escape into space above these field lines and so the speed of the solar wind tends to be slow here. Open field lines are the reverse, they emanate from the Sun and connect with the interplanetary magnetic field of the Solar System. They are magnetic highways along which the plasma can flow freely, and give rise to the fast solar wind.

Daniele and Gary proved that switchbacks occur when there is an interaction between a region of open field lines and a region of closed field lines. As the field lines crowd together, they can reconnect into more stable configurations. Rather like cracking a whip, this releases energy and sets an S-shaped disturbance traveling off into space, which a passing spacecraft would record as a switchback.

According to Gary Zank, who proposed one of the theories for the origin of switchbacks, “The first image from Metis that Daniele showed suggested to me almost immediately the cartoons that we had drawn in developing the mathematical model for a switchback. Of course, the first image was just a snapshot and we had to temper our enthusiasm until we had used the excellent Metis coverage to extract temporal information and do a more detailed spectral analysis of the images themselves. The results proved to be absolutely spectacular!”

Together with a team of other researchers, they built a computer model of the behavior, and found that their results bore a striking resemblance to the Metis image, especially after they included calculations for how the structure would elongate during its propagation outwards through the solar corona.

“I would say that this first image of a magnetic switchback in the solar corona has revealed the mystery of their origin” says Daniele, whose results are published in a paper in The Astrophysical Journal Letters.

Solar switchback mystery solved

In understanding switchbacks, solar physicists may also be taking a step toward understanding the details of how the solar wind is accelerated and heated away from the Sun. This is because when spacecraft fly through switchbacks, they often register a localised acceleration of the solar wind.

“The next step is to try to statistically link switchbacks observed in situ with their source regions on the Sun,” says Daniele. In other words, to have a spacecraft fly through the magnetic reversal and be able to see what’s happened on the solar surface. This is exactly the kind of linkage science that Solar Orbiter was designed to do, but it does not necessarily mean that Solar Orbiter needs to fly through the switchback. It could be another spacecraft, such as Parker Solar Probe. As long as the in-situ data and remote sensing data is concurrent, Daniele can perform the correlation.

“This is exactly the kind of result we were hoping for with Solar Orbiter,” says Daniel Müller, ESA Project Scientist for Solar Orbiter. “With every orbit, we obtain more data from our suite of ten instruments. Based on results like this one, we will fine-tune the observations planned for Solar Orbiter's next solar encounter to understand the way in which the Sun connects to the wider magnetic environment of the Solar System. This was Solar Orbiter’s very first close pass to the Sun, so we expect many more exciting results to come.”

Solar Orbiter’s next close pass of the Sun – again within the orbit of Mercury at a distance of 0.29 times the Earth-Sun distance – will take place on 13 October. Earlier this month, on 4 September, Solar Orbiter made a gravity assist flyby at Venus to adjust its orbit around the Sun; subsequent Venus flybys will start raising the inclination of the spacecraft’s orbit to access higher latitude – more polar – regions of the Sun.

Notes for editors

Observation of a magnetic switchback in the solar corona by D. Telloni et al is published in The Astrophysical Journal Letters. DOI: https://iopscience.iop.org/article/10.3847/2041-8213/ac8104

The research will be presented this week at the 8th Solar Orbiter Workshop in Belfast, Northern Ireland.

Related link:

Solar Orbiter: https://www.esa.int/Science_Exploration/Space_Science/Solar_Orbiter

Images, Videos, Text, Credits: ESA & NASA/Solar Orbiter/EUI & Metis Teams and D. Telloni et al. (2022)/Zank et al. (2020).

Best regards, Orbiter.ch

European scientists are running out of solutions to send the Euclid telescope into orbit

 

ESA - Euclid Mission logo.

Sept. 11, 2022

The queue to take advantage of a ticket to space continues to lengthen in Europe. Since Soyuz is no longer an option since the invasion of Ukraine, satellites and probes are waiting for Ariane 6. The Euclid telescope, in particular, could remain stuck on the ground for almost two more years.

The astrophysicists see their project completed, but at a standstill.

Image above: The Euclid space telescope, currently completed at Thales Alenia Space. Image Credit: Thales Alenia Space.

Do without Soyuz

Compared to the numerous Russian announcements or threats regarding the future of the International Space Station, the sanctions and counter-sanctions concerning the Soyuz launchers sent from the Guiana Space Center (CSG) have been somewhat forgotten. Indeed, two days after the invasion of Ukraine, Roscosmos announced the repatriation of its teams who were in Guyana as well as the end of the takeoffs of the iconic Russian launcher.

Immediately, European officials said they were looking for alternatives, but six months later these have yet to materialize. Several Soyuz launches were planned from the CSG this year, in particular within the framework of the Galileo program (two pairs of satellites), but also in the service of the French defense with the “spy” satellite CSO-3… Others were also planned for 2023, in particular in collaboration with the European Space Agency (ESA) to send the earth observation satellite EarthCare, the radar satellite Sentinel-1C, and the galaxy observer telescope, Euclid. Since February, both in public and behind the scenes, each team has been looking for the least penalizing solution.

Image above: It was simple and effective... until the decision to invade Ukraine. Image Credits: ESA/CNES/Arianespace/CSG/S. Martin.

Ariane 6 is still absent

The options for sending a telescope like Euclid into orbit are few, however. Already, a change of launcher implies additional work, because the flight profile and the associated constraints (vibrations, firing duration, ejection point to reach the Earth-Sun L2 Lagrange point) will change.

In reality, if the ESA sticks to its own specifications, it must use a European launcher, that is to say Ariane 6. With one problem: the rocket is not available today, any more than it will be in time to replace Soyuz. The maiden lift-off of Ariane 6 is now more or less scheduled for the first half of 2023. No specific date has been announced, institutions and manufacturers are awaiting the results of the current campaign of combined tests which will last several more month. And even so, do not expect a crowd of takeoffs from the new launcher in its first year of operation. Even if Ariane 6 is eagerly awaited and everything goes well for its inaugural launch (the teams are working on it, but it is not guaranteed), it will take time to get into cruising speed.

Euclid spacecraft. Animation Credit: ESA

A heavy scientific review

Euclid's scientific teams were therefore faced with an agenda that initially seemed impossible to them: they must prepare for takeoff of their vehicle by the end of the year... 2024. And this, while it has been sold out since the summer of 2022, in the premises of Thales Alenia Space in Cannes! This postponement of more than 18 months goes badly, already because it results in a big budget overrun. The telescope itself is indeed finished, so it will have to be mothballed, in impeccable conditions, which costs a fortune (we are talking about between 5 and 7 million euros per month, i.e. practically 100 million euros of storage before sending to Guyana). There is also the scientific impact of the teams and positions that will have to be reformed, with many laboratories operating on fixed-term contracts (particularly among doctoral and post-doctoral students), not to mention the inevitable grant application files funds.

Moreover, the teams hoped to be operational before the Americans. Euclid is theoretically an incredible instrument, capable of achieving on the scale of galaxies what the Gaia mission accomplishes for the stars in our vicinity. It would make it possible to constitute a formidable catalog of galaxies, clusters, their shape, their age, their spectrum, etc. with in particular a prestigious scientific objective, to use these data to understand the acceleration of the Universe and to decipher the role of dark energy.

In 2026-27, the United States will (if all goes well) send its new Nancy Grace Roman Telescope (NGR) into orbit, and it too will have capabilities in this area, albeit with complementary measurements. So that they can work in tandem (and not in competition), it is important that the Euclid data is already available when the NGR begins its mission… Even if it is possible that the American telescope will also suffer from delays.

Image above: Euclid remains on the lookout. But will it emerge from a clean room before the end of 2024? Image Credit: Thales Alenia Space.

Not on top of the pile

Finally, and despite requests to the ESA, Euclid does not seem to become a priority file. The European Union is already pressing the agency for other satellites. The next Galileo units must be sent into orbit as well as Sentinel-1C, which will replace the 1B radar unit which has definitely broken down this year. The French State is pushing for its part to complete the deployment of its CSO constellation, highly prized military optical observation while the war is raging less than 2,000 km from our borders.

For some scientists, ESA's commitment to only wanting to use European launchers is more stubborn than a sovereignty issue: Ariane 6 is costing them years of delay. Some even fear that Arianespace, faced with deadlines, will put the needs of its flagship customer for years to come, Amazon, ahead of those of their telescope. It should be noted that for ESA, and even more for its member countries very involved in launchers (France, Germany or Italy), the alternative makes people cringe, because it is almost always SpaceX that comes back on the table.

Indeed, the international market is in tension. Without Russia, ESA could turn to India, but the country has its own problems in the launcher sector (rhythm and reliability). Japan, too, is transitioning to its next-generation Ariane 6 competitor H-3, and other US partners either don't have the appropriate rockets or have full schedules for several years. And the European NewSpace sector, for its part, should not be there soon enough.

Image above: A large "map" simulated by the Euclid telescope team to know what to expect regarding its future results. Image Credits: J. Carretero (PIC), P. Tallada (PIC), S. Serrano (ICE) and the Euclid Consortium Cosmological Simulations SWG.

The American option

So what to do? ESA director Josef Aschbacher said in August that he had opened discussions with SpaceX officials, not necessarily for Euclid, but to relieve the European flight schedule, which had become untenable.

The affair will not be settled in a few weeks, but it is also a way of warning the member countries a few months before the large and very important ministerial meeting of the European Space Agency. The latter takes place every three years, and representatives as ministers of the member nations of the ESA will decide on its budgets as well as its future. The appointment will be scrutinized for all future missions, currently threatened by inflation which blocks budgets sometimes fixed a decade in advance. And above all, the pitcher crisis will play a central role.

Related links:

Euclid: https://www.esa.int/Science_Exploration/Space_Science/Euclid_overview

Arianespace: https://www.arianespace.com/

Images (mentioned), Text, Credits: ESA/Arianespace/Clubic/Eric Bottlaender/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch

Potentially habitable super-Earth discovered just 100 light-years away

 

NASA - Transiting Exoplanet Survey Satellite (TESS) logo.

Sept. 11, 2022

Image above: Two new super-Earths have been unearthed by an international team of astronomers, both orbiting the star LP 890-9. And one of them would be in the habitable zone! Image Credits: NASA/JPL-Caltech.

Two new super-Earths are added today to the list of exoplanets discovered. Unearthed thanks to the telescopes of the Speculoos project (Search for habitable Planets EClipsing ULtra-cOOl Stars) which consists of looking for habitable planets around faint and cold stars, they orbit around the star LP 890-9, also called TOI- 4306 or Speculoos-2.

This small red dwarf star is located some 100 light-years from Earth, and happens to be the second coldest star around which exoplanets have ever been found! After Trappist-1, the coldest star known to host planets, 7 to its credit! The two new findings were detailed in a study published in the journal Astronomy & Astrophysics.

Orbital periods of 2 and 8 days, yet one of the two is in the zone of habitability

The two planets orbit their star rapidly: the innermost completes a full rotation in just 2.73 days, and the other in 8.46 days! The inner planet, called LP 890-9b, is 30% larger than Earth. Initially detected by NASA's Tess (for Transiting Exoplanet Survey Satellite) space telescope, which detects nearby exoplanets by the transit method, it was then confirmed and then characterized, thanks to Speculoos.

Image above: The Transiting Exoplanet Survey Satellite (TESS) Data Processing Pipeline processes the raw pixels, extracts photometry and astrometry for each target star, identifies and removes systematic errors, flags transiting planet signatures, and performs a suite of diagnostic tests in order to help detect exoplanets. Image Credits: NASA/JPL-Caltech.

"Tess searches for exoplanets using the transit method, by simultaneously monitoring the brightness of thousands of stars, looking for slight obscurations that could be caused by planets passing in front of their stars", explains Laetitia Delrez in a press release, first author of study and postdoctoral researcher at the University of Liège.

“However, follow-up with ground-based telescopes is often needed to confirm the planetary nature of detected candidates and refine measurements of their orbital sizes and properties. Indeed, the Tess telescope is not very sensitive to infrared, and the star LP 890-9 emits mainly in this area.

Image above: Comparison between the LP 890-9 system and the inner Solar System. The LP 890-9 system is much more compact: its two planets could easily fit inside the orbit of Mercury, the innermost planet of our Solar System. Image Credits: Adeline Deward, Rise-Illustration.

As for the second planet, the outermost, it is the one that attracts the most attention from researchers: baptized LP 890-9c and of a size similar to LP 890-9b, it would be located in the habitability zone although it has a very short orbital period: only 8.5 days!

“Although this planet orbits very close to its star, at a distance about 10 times shorter than that of Mercury around our Sun, the amount of stellar irradiation it receives is still small, and could allow the presence of liquid water on the surface of the planet, provided there is sufficient atmosphere, explains Francisco J. Pozuelos, co-author of the study and researcher at the Institute of Astrophysics of Andalusia. This is because the star LP 890-9 is about 6.5 times smaller than the Sun and has a surface temperature half that of our star. This explains why LP 890-9c, despite being much closer to its star than Earth is to the Sun, might still have conditions that support life. »

The term "super-Earth" or "super-Earth" designates an exoplanet whose mass is between one tenth of that of the Earth and 5 times its mass. The term, which is often associated with a rocky planet of a mass similar to Earth, is quite recent; it was introduced in 2002 following the use of "super-earth" in a scientific journal. Although we often speak of a telluric planet located in the habitability zone when we designate a super-earth, the nature of the latter is not necessarily rocky: there are gaseous super-earths!

A prime target for the search for life by James-Webb

This discovery is thus encouraging for the search for life: the star LP 890-9 becomes one of the main targets of choice for James-Webb, after the planets of the Trappist-1 system! According to Laetitia Delrez, it would even be a prime target, especially for the greater chemical traceability of its atmosphere.

Image above: Artist's impression of the Trappist-1 system compared to the Solar System. The surface of each Trappist-1 planet is based on possible physical scenarios. The green zone corresponds to the “habitable zone” of liquid water. Image Credits: NASA/JPL-Caltech.

“This comparison, however, ignores the fact that LP 890-9c is located near the inner limit of the habitable zone and therefore could have a particularly water vapor-rich atmosphere, which would then enhance its atmospheric signals. Moreover, the models often differ as to the exact position of this interior limit of the habitable zone according to the characteristics of the star. The discovery of LP 890-9c therefore offers a unique opportunity to better understand and constrain the conditions of habitability around the smallest and coldest stars in our solar neighborhood,” she concludes.

Related links:

Astronomy & Astrophysics:
https://www.aanda.org/10.1051/0004-6361/202244041

NASA's Transiting Exoplanet Survey Satellite (TESS):
https://www.nasa.gov/tess-transiting-exoplanet-survey-satellite

Images (mentioned), Text, Credits: NASA/Futura  Science/Lée Fournasson/Orbiter.ch Aerospace/Roland Berga.

Best regards, Orbiter.ch

SpaceX Starlink 60 launch

 

SpaceX - Falcon 9 / Starlink Mission patch.

Sept. 11, 2022

Falcon 9 carrying Starlink 60 liftoff

A SpaceX Falcon 9 launch vehicle launched 34 Starlink satellites (Starlink-60 / Starlink 4-2)  and AST SpaceMobile’s BlueWalker 3 satellite to low-Earth orbit, from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida, on 11 September 2022, at 01:20 UTC (10 September, at 21:20 EDT).

SpaceX Starlink 60 launch & Falcon 9 first stage landing, 11 September 2022

Following stage separation, Falcon 9’s first stage landed on the “A Shortfall of Gravitas” droneship,  stationed in the Atlantic Ocean. Falcon 9’s first stage (B1058) previously supported thirteen missions: Crew Demo-2, ANASIS-II, CRS-21, Transporter-1, Transporter-3 and eight Starlink missions.

Related links:

SpaceX: https://www.spacex.com/

Starlink: https://www.starlink.com/

Image, Video, Text, Credits: SpaceX/SciNews/Orbiter.ch Aerospace/Roland Berga.

Greetings, Orbiter.ch