Tag: spaceflight

NASA officially expresses concerns about proposed private communications constellation

8:55 am

For what appears to be an unprecedented action, NASA has officially expressed opposition to a proposed private satellite constellation by the company AST & Science.

NASA’s position was released in a comment to the FCC, where the company has requested a communications license to operate its satellites.

At issue are plans put forth by AST & Science, which intends to build a constellation of more than 240 large satellites, essentially deploying “cell towers” in space to provide 4G and possibly 5G broadband connection directly to cell phones on Earth. The company, based in Midland, Texas, calls its constellation “SpaceMobile” and has raised an estimated $120 million.

The space agency felt compelled to comment on AST’s proposal for several reasons. Most notably, the proposed altitude for the SpaceMobile constellation lies near the “A-Train,” a group of 10 Earth-science monitoring satellites operated by NASA and the US Geological Survey, as well as partners in France and Japan. “Historical experience with the A-Train constellation has shown that this particular region of space tends to produce a large number of conjunctions between space objects,” the NASA letter states.

The satellites are also very large. In order to provide service, AST plans to build spacecraft with large phased array antennae—900 square meters. According to NASA, in planning for potential conjunctions with other satellites and debris in this orbit, this would require proscribing a “hard-body radius” of 30 meters, or as much as 10 times larger than other satellites.

Maneuvering around the proposed SpaceMobile constellation would be extraordinarily taxing, NASA said. “For the completed constellation of 243 satellites, one can expect 1,500 mitigation actions per year and perhaps 15,000 planning activities,” the space agency stated. “This would equate to four maneuvers and 40 active planning activities on any given day.”

The company has said it is willing to work with NASA to ease its concerns. For NASA to take this particular step however is most strange, especially considering the size of this constellation, 240 satellites. This number is tiny compared to the multi-thousands being proposed by SpaceX, Amazon, and OneWeb. Their large size footprint certainly could be a factor, but it does seem puzzling for the space agency to pick out this particular constellation for opposition, and none of the others.

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Signal to Voyager-2 confirms upgrade of NASA’s Deep Space Network

8:42 am

After months of downtime in order to install a major and very badly needed upgrade to NASA’s Deep Space Network (DSN) (the worldwide array of radio dishes used to communicate with planetary probes throughout the solar system) a test command to Voyager-2 beyond the orbit of Pluto was sent, received, and executed successfully this week, proving the upgrade is working.

The call to Voyager 2 was a test of new hardware recently installed on Deep Space Station 43, the only dish in the world that can send commands to Voyager 2. Located in Canberra, Australia, it is part of NASA’s Deep Space Network (DSN), a collection of radio antennas around the world used primarily to communicate with spacecraft operating beyond the Moon. Since the dish went offline, mission operators have been able to receive health updates and science data from Voyager 2, but they haven’t been able to send commands to the far-flung probe, which has traveled billions of miles from Earth since its 1977 launch.

Among the upgrades to DSS43, as the dish is known, are two new radio transmitters. One of them, which is used to talk with Voyager 2, hasn’t been replaced in over 47 years. Engineers have also upgraded heating and cooling equipment, power supply equipment, and other electronics needed to run the new transmitters.

The successful call to Voyager 2 is just one indication that the dish will be back online in February 2021.

The upgrade has been overdue for years, and is essential to provide sufficient communications capability for the future interplanetary mission presently planned.

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Layered mesa on Mars

2:41 pm

Layered mesa on Mars
Click for full image.

Cool image time! The photo to the right, rotated, cropped, and reduced to post here, was taken on June 24, 2020 by the high resolution camera on Mars Reconnaissance Orbiter (MRO). It shows a distinctive mesa in a mountainous region in the cratered highlands of Mars, just north of Hellas Basin, the deepest basin on the red planet.

The mesa’s most distinctive feature are its terraced layers, a feature that MRO has found in numerous other places surrounding and inside Hellas Basin (see for example the cool images here, here, here, here, here, and here.)

On Earth the assumption would be that these terraced layers imply different sedimentary layers that erode at different rates, as best illustrated by the Grand Canyon in Arizona. On Mars that assumption is not unreasonable, but unlike Earth, those layers could not have been formed in connection with large ocean bodies creating seafloor layers from the deposit of sealife over centuries. Some other geological process over time formed them, with volcanism, either from volcanoes or impact, being the most likely.
» Read more

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SpaceX to live stream 50,000 foot hop of Starship

9:20 am

Capitalism in space: Elon Musk yesterday announced that SpaceX will publicly live stream the 50,000-foot hop of Starship prototype #8, expected sometime in the next two weeks. His tweet:

Sure, although it might be quite a short livestream! Lot can go wrong, but we’ll provide video, warts & all. You will see every frame that we do.

Up until now the public has had to depend on the independent live streams being put out by local residents still living in Boca Chica, Texas, which did not know SpaceX’s exact schedule. When SpaceX does it they will likely provide more specific launch times. They will also probably provide detailed accurate commentary.

Also, this update on the status of Starship development notes that the primary goal of that hop is testing the ability of the ship’s fins and systems to control the ship’s initial descent on its return to Earth, flying on its side like the Space Shuttle. If they have problems getting the ship upright for a vertical landing and it ends up in the ocean that will not surprise them. A successful vertical landing would be icing on the cake.

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Another movie of OSIRIS-REx’s sample-grab-and-go at Bennu

10:08 am

The OSIRIS-REx science team has released another movie showing the sample-grab-and-go at Bennu, this time from a different camera.

The movie, made up of 189 images taken over three hours by the spacecraft’s navigation camera NavCam-2, can be seen at the link.

In the middle of the sequence, the spacecraft slews, or rotates, so that NavCam 2 looks away from Bennu, toward space. OSIRIS-REx then performs a final slew to point the camera (and the sampling arm) toward the surface again.

As the spacecraft nears site Nightingale, the sampling arm’s shadow comes into view in the lower part of the frame. Shortly after, the sampling head impacts site Nightingale (just outside the camera’s field of view to the upper right) and fires a nitrogen gas bottle, which mobilizes a substantial amount of the sample site’s material. Several seconds later, the spacecraft performs a back-away burn and the sampling arm’s shadow is visible against the disturbed surface material.

The team continues to investigate what caused the extremely dark areas visible in the upper and middle parts of the frame. The upper area could be the edge of the depression created by the sampling arm, a strong shadow cast by material lofted from the surface, or some combination of the two. Similarly, the middle dark region that first appears in the lower left of the image could be a depression caused by one of the spacecraft thrusters as it fired, a shadow caused by lofted material, or a combination of both.

It strikes me that getting post impact images of Nightingale is essential, if at all possible.

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A buried crater on Mars

3:35 pm

Close overview map

The overview map to the left indicates the general terrain surrounded today’s cool image. The white rectangle is the area covered by this image, taken on July 4, 2020 by the high resolution camera on Mars Reconnaissance Orbiter. If you look close you can see that this photograph covers the eastern rim of what looks like an ancient and mostly buried crater on Mars. This unnamed crater is about 17 miles across.
» Read more

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New data: young red dwarf stars are not nice stars for life

12:50 pm

New data from both the Chandra X-ray Observatory and the Hubble Space Telescope has reinforced earlier data that suggested the strong flares emitted by young red dwarf stars make them inhospitable to the development of life on any planet in the habitable zone.

A new study using NASA’s Chandra X-ray Observatory and Hubble Space Telescope examined the red dwarf called Barnard’s Star, which is about 10 billion years old, more than twice the current age of the Sun. Red dwarf stars are much cooler and less massive than the Sun, and are expected to live much longer lives because they do not burn through their fuel as fast. Barnard’s Star is one of the closest stars to Earth at a distance of only 6 light-years.

Young red dwarfs, with ages less than a few billion years, are known as strong sources of high-energy radiation, including blasts of ultraviolet light and X-rays. However, scientists know less about how much damaging radiation red dwarfs give off later in their lifetimes.

The new observations concluded that about 25% of the time, Barnard’s Star unleashes scorching flares, which may damage the atmospheres of planets closely orbiting it. While its only known planet does not have habitable temperatures, this study adds to evidence that red dwarfs may present serious challenges for life on their planets.

It is very important to remember that this data makes difficult the formation of life, as we know it. Since we know so little about such processes, as well as the formation processes of solar systems, it is too early to say whether no life can ever form around such stars.

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Scientists confirm another 44 black hole mergers detected by gravitational waves

12:16 pm

Scientists have now confirmed that since the first detection of a gravitational wave five years ago they have detected another 44 black hole mergers in the same manner.

A global network of scientists has completed the first major analysis of gravitational wave data, providing exciting insights into some of the most exotic objects in the Universe. “We are announcing the discovery of 44 confirmed black hole mergers, which is a more than a four-fold increase in the number of previously known gravitational-wave signals,” says Shanika Galaudage from Australia’s Monash University, who was part of the research team.

…Their results are described in a trio of papers on the pre-print server arXiv. The first paper describes 39 new detections from the first half of the observing run, primarily of binary black hole systems. This brings the total number of gravitational wave events detected to 47, of which 44 are confidently double black holes, two are confidently double neutron stars, and one is still uncertain.

They think they are detecting more black hole mergers because they are heavier and thus emit bigger and more easily detected waves. They are also finding that the black hole mergers fall into two classes, two holes spinning in the same direction and two holes spinning in opposite or randomly different directions. The former formed together as a binary star system. The latter formed independently and somehow ended up linked up and merging.

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U.S. court orders India’s s space agency ISRO to pay $1.2 billion

11:21 am

A U.S. court has ordered Antrix, the commercial arm of India’s space agency ISRO, to pay $1.2 billion to Devas, a private company with operations in both India and the United States, for a contract they canceled arbitrarily in 2011.

This is a very complicated story going back many years. ISRO’s Antrix and Devas had agreements beginning in 2005 to work together to develop commercial satellites, with Antrix building the satellites and Devas commercializing bandwidth. In 2011 the India government cancelled the contracts unilaterally.

On February 25, 2011, Antrix issued a termination notice to Devas, which among other things stated that the policy decision was of the central government, acting in its sovereign capacity is the event of force majeure, which was an occurrence on February 23, 2011, PTI report said. “The scope and duration of the said decision cannot be anticipated. It is likely to be indefinite. It is not possible for Antrix to take any effective step to resume the obligations under the agreement,” Antrix was quoted as saying.

One of the reasons for the cancellation were accusations that payoffs were occurring between officials at both Antrix and Devas to make the deal happen.

Devas has been fighting in numerous courts for years to get compensation for that cancellation.

ISRO can probably ignore this U.S. court decision, except that if it does it will make it very difficult, if not impossible, for ISRO to do any work in partnership with the U.S., such as in the Artemis program. As soon as they try to do so, Devas will slap a lien on that operation, demanding payment.

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Russian astronaut: Crack on ISS could be from “external impact”

10:48 am

Russian astronaut, Sergei Ryzhikov, today noted that to him the 1-inch crack causing the leak on ISS appeared to have been caused by an “external impact.”

Speaking with Flight Director of the Russian segment of the ISS Vladimir Solovyov, Russian cosmonaut Sergei Ryzhikov said: “If you take a closer look at the picture, there are changes of color in the middle of the crack.”

“We suspect an external impact,” Ryzhikov said adding that the place of the suspected impact should be examined during the crew’s next spacewalk, which is scheduled for November 18.

This conclusion is different than that expressed yesterday by another Russian astronaut, who suggested the crack was from age and wear and tear of the twenty-year-old Zvezda module.

Either way, an inspection of the exterior point of the crack is essential in order to permanently seal it, and that inspection will tell us one way or the other the cause of the crack.

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War between two Spanish space balloon companies

10:35 am

Capitalism in space: A legal battle is developing between two different Spanish high altitude space balloon companies, one that came first, and a second that is being backed by a venture capitalist who had previously worked at the first.

Jose Mariano Lopez Urdiales, an MIT-trained aeronautics engineer who founded Zero 2 Infinity 11 years ago, says Kemel Kharbachi, the now CEO of EOS X Space, worked closely with the company to raise a €1m investment for Zero 2 Infinity. But the funding deal never happened.

Instead, Kharbachi, whose previous experience has focused on tourism and catering, has emerged to build his own rival space balloon business.

It does appear, from the details outlined in the article, that Kharbachi essentially stole the concept and designs from Zero 2 Infinity in order to form his own company.

As these Spanish companies fight it out, a third company in America, Space Perspectives, hopes to begin flying tourists on its stratospheric balloon, dubbed Neptune, by ’24.

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ESA maps out first launch schedule for new rockets

3:19 pm

Capitalism in space? The European Space Agency (ESA) today laid out the development roadmap that will lead to the launch of two new rockets, the Vega-C being built by the Italian company Avio, and the Ariane 6 being built by ArianeGroup.

The Vega-C is a more powerful version of the Vega rocket, aimed at capturing the smaller satellite market. It maiden flight is now scheduled for June ’21.

The Ariane 6 is aimed at replacing the Ariane 5, Europe’s big workhorse rocket, but to do so at a lower cost. Its maiden flight is now set for the second quarter of ’22, a significant delay from the previously announced target date in ’21, which itself was a delay from the original late ’20 launch date.

Ariane 6 however has not succeeded in cutting costs enough to match its competitor SpaceX, and thus it continues to have trouble attracting customers, even among ESA’s partner nations that it is meant to serve. These issues have led to rumors that ESA is already looking to either significantly upgrade Ariane 6 (before it even flies), or replace it entirely wit a new re usable rocket.

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OSIRIS-REx completes storage of Bennu sample

2:33 pm

OSIRIS-REx has now completed placing its sample from the asteroid Bennu in the Sample Return Capsule that will bring it back to Earth.

On the afternoon of Oct. 28, following the backout check, the mission team sent commands to disconnect the two mechanical parts on the TAGSAM arm that connect the sampler head to the arm. The spacecraft first cut the tube that carried the nitrogen gas that stirred up the sample through the TAGSAM head during sample collection, and then separated the collector head from the TAGSAM arm itself.

That evening, the spacecraft completed the final step of the sample stowage process –closing the SRC. To secure the capsule, the spacecraft closed the lid and then fastened two internal latches. As of late Oct. 28, the sample of Bennu is safely stored and ready for its journey to Earth.

Because they decided it was better to store the sample immediately and not risk losing it, they were unable to do the spin test that would told them how much sample they obtained. For this reason we will not know the amount until the sample capsule is opened here on Earth, after its return on September 24, ’23.

UPDATE: You can watch if short movie of the Sample Return Capsule closing here.

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Meteor over Alaska sets off volcano sensors

8:49 am

A bright fireball meteor that passed over western Alaska on October 15th caused enough disturbance in the atmosphere to set off volcano sensors throughout the region.

The event, which took place on October 15, triggered six of the sensors’ alarms at a new monitoring station on the Kenai Peninsula. The sensors are built to detect low-frequency sound waves in the atmosphere during volcanic activity, but in this case they picked up waves coming from the meteor that had streaked across the sky around 360 miles away.

In a Facebook post, the USGS said the meteor also triggered an alarm at Mount Spurr—a large, active volcano that sits around 80 miles from Anchorage that last erupted in 1992. However, as other monitoring systems also picked up on the waves, “it quickly became clear that this was not activity at Mount Spur,” the post said.

It is ironic, but those sensors, designed to monitor volcano eruptions, have likely also provided scientists some worthwhile data on asteroids.

Hat tip Commander Cobra of Task Force Gryphon

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Hayabusa-2’s impactor shook Ryugu

8:26 am

When Hayabusa-2 fired an impactor into the asteroid Ryugu in order to access subsurface material in a sample grab, it apparently shook the asteroid, shifting boulders and rocks as far as 130 feet away.

The artificial impactor disturbed boulders within a 30m radius from the center of the impact crater- providing important insight into asteroids’ resurfacing processes.

Professor ARAKAWA Masahiko (Graduate School of Science, Kobe University, Japan) and members of the Hayabusa2 mission discovered more than 200 boulders ranging from 30cm to 6m in size, which either newly appeared or moved as a result of the artificial impact crater created by Japanese spacecraft Hayabusa2’s Small Carry-on Impactor (SCI) on April 5th, 2019. Some boulders were disturbed even in areas as far as 40m from the crater center. The researchers also discovered that the seismic shaking area, in which the surface boulders were shaken and moved an order of cm by the impact, extended about 30m from the crater center. Hayabusa2 recovered a surface sample at the north point of the SCI crater (TD2), and the thickness of ejecta deposits at this site were estimated to be between 1.0mm to 1.8cm using a Digital Elevation Map (DEM).

This data makes all the more important for OSIRIS-REx to get post-sample-grab images of its Nightingale site, if at all possible.

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OSIRIS-REx engineers successfully place sample collector in return capsule

7:55 am

Stowing OSIRIS-REx's sample from Bennu
Click for full image.

OSIRIS-REx engineers have successfully placed the sample collector head holding the material captured from the asteroid Bennu in the return capsule that will bring it back to Earth.

Yesterday, NASA’s OSIRIS-REx mission successfully placed the spacecraft’s sample collector head into its Sample Return Capsule (SRC). The first image shows the collector head hovering over the SRC after the Touch-And-Go Sample Acquisition Mechanism (TAGSAM) arm moved it into the proper position for capture. The second image shows the collector head secured onto the capture ring in the SRC. Both images were captured by the StowCam camera.

Today, after the head was seated into the SRC’s capture ring, the spacecraft performed a “backout check,” which commanded the TAGSAM arm to back out of the capsule. This maneuver is designed to tug on the collector head and ensure that the latches – which keep the collector head in place – are well secured. Following the test, the mission team received telemetry confirming that the head is properly secured in the SRC.

The next step will be to seal the capsule for return to Earth. However, based on the two images above, the sample is now relatively secure, as the opening where material could escape is now held face down in the capsule.

The spacecraft will head back to Earth in March ’21, with the sample capsule landing on Earth on September 24, 2023. I do not know whether it will be possible in the next six months to get new images of the Nightingale touch-and-go site, but have emailed Erin Morton, head of the communications for the science team, and asked. I will update this post when I hear back from her.

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Russian astronaut: ISS crack could be result of Zvezda module’s age

7:31 am

A Russian astronaut just returned from ISS admitted during a press conference that the recently located crack on the 20-year-old Zvezda module that was the source of the long-term slow leak could be the result of the module’s age.

“Twenty years are actually an absolute record for all space stations now. And we see now that something is changing and something requires greater [attention]. Again, if we go back to the leak, the hull is already beginning to give cracks and scratches somewhere, that is, we see the limits [of the ISS structure’s service life],” [cosmonaut Ivan Vagner] said.

The crack has been sealed temporarily, with a more permanent seal put in place after the nearby docking port is cleared and the hatches closed and out of the way.

If Russian astronauts are noticing wear and tear in Zvezda that is bad enough to cause “cracks”, this raises some very serious issues for ISS’s future, as replacing that module on ISS will be complicated and expensive, and at this point no one has even begun planning such an replacement.

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Is this the planned landing site of China’s Mars rover?

7:21 am

The prime landing site for China's Mars rover?

According to this Space News article, a report in the Chinese press, since revised to remove the information, had provided precise coordinates on Mars for the prime candidate landing site for China’s Tianwen-1 rover.

[I]nformation published in an article (in Chinese) in the official China Space News publication following launch in July provides a specific primary landing site. The article reported landing coordinates of 110.318 degrees east longitude and 24.748 degrees north latitude, within the southern portion of Utopia Planitia. Online versions of the article have since been edited to remove the coordinates; however, these remain published by sources citing the article.

The mosaic on the right, made up of two images taken by Mars Reconnaissance Orbiter’s (MRO) context camera (found here and here) shows this location with the white cross. The white box is the area covered by the only image taken of this area by MRO’s high resolution camera.

As these photos show, this location, in a part of Mars’ northern lowland plains dubbed Utopia Planitia, is generally smooth and flat, making for a relatively safe landing site. At the same time, it has craters and some ridges and hills that could pose issues.

That the coordinates were removed from the Chinese press story suggests that this might be the prime site, but until Tianwen-1 gets into Mars orbit and begins scouting the site with its own high resolution images, they want to reserve judgement. The spacecraft arrives in orbit in February ’21, and they presently plan to land the rover in May. That gives them three months to scout this location as well as a secondary landing site on the other side of Mars, in the Chryse Planitia northern lowlands [pdf], the same region where Viking 1 and Mars Pathfinder landed.

Once they have done this they will be able to refine the location more precisely.

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SpaceX finds clogged valves in several Merlin engines

5:56 am

Capitalism in space: SpaceX has discovered that the problem that caused a recent launch abort of a GPS satellite was a coating that clogged valves in several newer Merlin engines.

Hans Koenigsmann, vice president of build and flight reliability at SpaceX, said teams initially weren’t able to figure out why two of nine engines triggered early-start sensors on Oct. 2, which forced computers to automatically scrub seconds before liftoff. After the engines were removed and shipped to Texas for testing, the anomaly surfaced again when sensors detected higher-than-expected engine chamber pressures.

The cause: a minuscule, almost undetectable amount of “masking lacquer,” which is used to protect engine components and surfaces during the production process. The lacquer is almost like a bright red nail polish. “We found a relief valve – a little line that goes to the relief valve – blocked in the gas generator,” Koenigsmann told reporters Wednesday. “That little red substance was blocking a relief valve that caused it to function a little bit earlier than it was supposed to.”

The gas generators are almost like little rocket engines themselves – they’re used to power a pump that then feeds propellants into the main engine chamber. But the blockage caused certain processes to begin too early.

Once the lacquer was removed the engines functioned perfectly.

The issue was also found in two engines on the new booster that was going to launch astronauts to ISS, which explains why that mission was delayed. The company is swapping out the engines, and is still targeting November 14th for that launch. In addition, NASA wants it to fly at least two missions beforehand to demonstrate the problem is fixed. One will be that GPS satellite, on November 4th. The other could be one of three different payloads on SpaceX’s busy schedule.

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Rocket Lab successfully launches 10 smallsats

9:19 pm

Capitalism in space: Rocket Lab today successfully placed ten smallsats into orbit using its Electron rocket, launched from New Zealand.

This was their second successful launch for the company since their launch failure on July 4th. Their next launch should be their first from the U.S., from Wallops Island, Virginia.

The leaders in the 2020 launch race:

27 China
18 SpaceX
12 Russia
4 ULA
4 Europe (Arianespace)
4 Rocket Lab

The U.S. now leads China 29 to 27 in the national rankings.

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