On Christmas morning of 2021, the James Webb Space Telescope successfully launched from Earth. Thomas Zurbuchen, now NASA's associate administrator for science, had made the call. If Webb was going to fail, he would take the blame.

Not only did Webb launch, but its Ariane 5 rocket performed the flight with such precision that the spacecraft was able to save precious fuel for maneuvering, thereby extending its lifetime. Over the next two weeks, engineers and scientists executed hundreds of steps to unfold and fully extend the telescope and its massive sunshield. And then, finally, on Monday, the spacecraft performed one final major burn of its thrusters, falling into a halo orbit around the L2 point.

This means that the Webb space telescope has reached its final destination, a 180-day orbit around this L2 point, which keeps the telescope in line with the Earth as both the instrument and planet orbit around the Sun. Here, while using a minimum amount of fuel to hold its position, Webb can use its sunshield to keep the infrared telescope and its instruments cold.

The work is not done. The telescope has 18 primary mirror segments, which are moved by 132 actuators. These actuators have already been tested and shown to work. Now, over the next three months, telescope operators will fine-tune the alignment of these mirrors. During this process, scientists will use a Sun-like star named HD84406 to focus the mirrors. This star is located about 240 light years from Earth and can be found in Ursa Major near the bowl of the Big Dipper.

At the same time, in the wake of the sunshield, these mirrors and their scientific instruments will continue to cool in order to be able to detect the weak, ultra-distant signals of heat from the Universe's oldest galaxies. //

What is it about HD84406 that makes it the one to use for focusing the mirrors?

There are probably lots of criteria, but I only know two of them:

1. It's in the same 1/3 of space that JWST can see (i.e. the telescope doesn't have to look towards the Sun to see it)
2. It has to be relatively bright (HD84406 is not visible to the naked eye but can be seen with binoculars).

I can't find a reference now, but IIRC it was also selected because it's isolated with nothing behind it that's close (in interstellar terms), so it's easier to determine if the focus is good because there's less background light.

With clearing skies and moderate winds, SpaceX's Falcon 9 rocket rideshare mission safely launched into space on Thursday. The first stage then sent its upper stage and a payload with 105 small satellites on its way into low Earth orbit. The Falcon 9 first stage made a smooth landing back near its launch site.

Remarkably, this single Falcon 9 rocket first stage has now launched 550 satellites into orbit, as well as one Cargo Dragon and one Crew Dragon. It has flown, on average, every two months since its first launch. It would seem that rocket re-use is more than a fad. //

niwax Ars Tribunus Militum et Subscriptor

Hispalensis wrote:

Quote:

Upon launch, it will become the third Falcon 9 first stage that SpaceX has flown 10 times.

First reaction: hmm, that's interesting...

Delayed reaction: 10 times? That is insane!

It is funny how our brain quickly accepts the extraordinary as the new normal

This booster has delivered two Dragon capsules to the ISS, first with two astronauts then with 3t of supplies, plus a GEO commsat, 295 LEO commsats, 9 traffic monitoring satellites, 48 earth observation satellites, an in-orbit data transfer demonstration constellation, a space tug with 18 payloads, a synthetic aperture radar and an optical spectrum observatory and 10-15 random other cubesats.

That is before todays launch of some 105 new satellites.

I'll repeat what I said way back on SSO-A: The unbelievable projections of the small sat industry have come true, only to be gobbled up by a workhorse F9 on it's 10th flight.

The other piece of news, less well-covered but still important, emerged during a news conference on Saturday. NASA's Mission Systems Engineer for the Webb telescope, Mike Menzel, said the agency had completed its analysis of how much "extra" fuel remained on board the telescope. Roughly speaking, Menzel said, Webb has enough propellant on board for 20 years of life.

This is twice the conservative pre-launch estimate for Webb's lifetime of a decade, and it largely comes down to the performance of the European Ariane 5 rocket that launched Webb on a precise trajectory on Christmas Day.

Prior to launch, the telescope was fueled with 240 liters of hydrazine fuel and dinitrogen tetroxide oxidizer. Some of this fuel was needed for course adjustments along the journey to the point in space, about 1.5 million km from Earth, where Webb will conduct science observations. The remainder will be used at Webb's final orbit around the L2 Lagrange point for station-keeping and to maintain its orbit.

So every kilogram of fuel saved on Webb's journey to the Lagrange point could be used to extend its life there. Because ten years seemed like a fairly short operational period for such an expensive and capable space telescope, NASA had already been contemplating a costly and risky robotic refueling mission. But now that should not be necessary, as Webb has at least two decades of life.

A lot of this comes down to the performance of the venerable Ariane 5 rocket. NASA and the European Space Agency reached an agreement more than a decade ago by which Europe would use its reliable Ariane 5 rocket to lift the telescope into space, and in exchange, European scientists would get time to use the telescope. //

The Ariane 5 program also selected the best components for Webb based upon pre-flight testing. For example, for the Webb-designated rocket, the program used a main engine that had been especially precise during testing. "It was one of the best Vulcain engines that we've ever built," Albat said. "It has very precise performance. It would have been criminal not to do it." //

Albat admitted that the days prior to launch were exhausting and nerve-wracking. But soon after the launch, Albat said he and the entire European space community could take pride as Webb took flight and began to unfurl its wings. Now, he said, "I feel totally relaxed." The same can be said for a lot of scientists who have been watching Webb's development for two decades.

The five layers of the sunshield are incredibly delicate. Each plastic-like sheet has the same thickness as a human hair and had to be stretched across a tennis-court-sized area. All of this had to be done in microgravity, an environment that could not be simulated in ground tests.

"It was the first time we deployed this system in zero-g, and we nailed it," said Alphonso Stewart, Webb deployment systems lead. "It's a really good testament to the work done by the teams."

So much could have gone wrong. During tests as recently as 2018, the sunshield layers were snagging during ground-based tests. It's not difficult to understand why. According to NASA, the unfolding and tensioning of the sunshield involved 139 of the telescope's 178 release mechanisms, 70 hinge assemblies, eight deployment motors, some 400 pulleys, and 90 individual cables totaling more than 400 meters in length.

By getting through the sunshield deployment process, therefore, NASA has surmounted the most complex aspect of unpacking the telescope in space and setting it up for operations.

"The sunshield deployment certainly was the most complex in terms of moving parts having to all work in harmony, and systems that were interrelated with one another," said James Cooper, the Webb telescope's sunshield manager. "The stuff that’s left from a deployment point of view is more conventional, such as hinges and motors."

Lots of hurdles to come, but a good start for the new observatory.

UUPlus software is specifically designed for Internet email and file transfer over slow and/or error prone connections such as mobile satellite phones, HF and V/UHF radio modems, and services such as Mobile Packet Data Service and BGAN. Our software is distributed as part of the UUPlus Satellite Email Service or is sold as a deployed systems solution for private or regional networks.

With compressed, bi-directional data transfer, UUPlus software achieves throughput speeds four or more times faster than standard POP/SMTP connections and twice that of general purpose accelerated satellite gateway software. UUPlus software will also connect reliably in situations where normal IP based protocols will timeout.

UUPlus is easy to install and maintain and supports most satellite networks including Inmarsat (MPDS, BGAN), Iridium (all phones, the Go! included), Globalstar (gateway connect), and Thuraya (gateway connect). In the deployed software versions, UUPlus supports Codan, Pactor, AX.25, and P.25 Radio.

In the latest instance of an Amazon-related venture attempting to use regulations and legal routes to suppress competition, Amazon’s Project Kuiper satellite internet venture wants the FCC to dismiss SpaceX’s application for the next generation of Starlink satellites.

In a document filed with the FCC in late August, Project Kuiper took the significant step of asking the regulatory body to entirely dismiss a SpaceX request to modify plans for the next generation of Starlink satellites. As previously discussed on Teslarati, SpaceX submitted that modification request on August 18th with one clear focus: optimizing Starlink satellites and the constellation’s orbital ‘shells’ to best take advantage of the imminent capabilities of the next-generation Starship launch vehicle. //

Nominally capable of launching at least 100 metric tons (~220,000 lb) to low Earth orbit (LEO) in a fully reusable configuration, Starship would boost the mass of Starlink satellites SpaceX could orbit with one launch by a factor of 5-6 or more relative to Falcon 9. In other words, with Starship, SpaceX could feasibly fill out its Starlink constellation at least 5-6 times faster than with Falcon 9. //

In turn, while not unprecedented, SpaceX chose to modify its license application for the second (or third) phase of Starlink satellites – a constellation made up of almost 30,000 spacecraft – to include two distinct options: a constellation where Starship is ready on time and one where it is not. Amazon’s Project Kuiper project, Effectively a Starlink clone helmed by former senior managers and engineers that SpaceX CEO Elon Musk personally ousted in 2018 for being slow and overcautious, Amazon’s Project Kuiper was apparently not happy with the changes its competitor made. //

Published six days later, SpaceX pulls no punches in its response to Amazon, raking the company through the coals for an incessant number (dozens) of filed objections to Starlink while simultaneously failing to address crucial FCC questions about the nature of the Project Kuiper constellation. Bizarrely, SpaceX’s response also accurately points out how Amazon’s legal team seemingly fails to understand SpaceX’s modification request, which poses two mutually exclusive constellation layouts with mostly marginal differences. Amazon’s central argument appears to be that SpaceX actually hasn’t submitted enough information by meticulously detailing two constellation layouts instead of one, claiming that it left “every major detail unsettled.”

As NASA’s Voyager 1 Surveys Interstellar Space, Its Density Measurements Are Making Waves
In the sparse collection of atoms that fills interstellar space, Voyager 1 has measured a long-lasting series of waves where it previously only detected sporadic bursts.

Until recently, every spacecraft in history had made all of its measurements inside our heliosphere, the magnetic bubble inflated by our Sun. But on August 25, 2012, NASA’s Voyager 1 changed that. As it crossed the heliosphere’s boundary, it became the first human-made object to enter – and measure – interstellar space. Now eight years into its interstellar journey, a close listen of Voyager 1’s data is yielding new insights into what that frontier is like.

SpaceX’s satellite internet service is a technological marvel — when it works

By Nilay Patel on May 14, 2021 10:00 am //

Starlink is a new satellite-based internet service from SpaceX. In beta, it promises up to 100Mbps download and 20Mbps upload speeds. Starlink currently has very limited availability. //

Starlink has set a long-term goal of 1Gbps down. It represents competition, something the American broadband market sorely lacks.

In that context, Starlink also represents something else: the American telecom policy establishment’s long-standing, almost religious belief that consumers are best served by something called “facility-based competition.” Starlink is a new facility for accessing the internet, one that does not rely on existing infrastructure. “Facility-based competition,” telecom lobbyists feverishly whisper while handing out their dirty, sweat-stained checks in Congress. “That is the American way.” //

Of course, the only thing a decades-long commitment to “facility-based competition” has brought to most Americans is… a total lack of competition. Reality, as I have said, is quite irritating. //

(by contrast, in europe, where the prevailing philosophy is called “service-based competition,” large incumbent providers are required to lease fiber access to competitors and there is a thriving market for internet access with much lower prices for much faster speeds. if the united states were in europe, it would have the most expensive broadband in the region.) //

look, i know you’re hyped up about starlink. i feel you. i also wish i could tweet a photo of dishy in my yard to every telecom ceo in the game and tell them to try harder. but the verge has long had a hard rule against reviewing products based on potential because the sad truth is that most tech products never, ever live up to their potential. and starlink, judged on its capabilities right now, is simply not a real competitor to the long, long coax wire running from my house to the local cable company fiber plant. it’s not even a great competitor to my data-capped-and-throttled “unlimited” at&t 5g service because i can reasonably work from home on that connection and i really can’t with starlink. and in the end, starlink’s traffic has to run over fiber in the ground anyway. //

all the people dreaming of starlink upsetting cable monopolies and reinventing broadband need to seriously reset their expectations. at best, starlink currently offers reasonably fast access with inconsistent connectivity, huge latency swings, and a significant uptick in time spent considering whether you can just get out the chainsaw and solve the tree problem yourself. //

maybe this will change as the company launches more satellites. maybe it will eventually work better in areas that are dominated by tall trees. maybe one day it will not drop out in wind and heavy rain. i didn’t give starlink a formal review score because the whole thing is openly in beta and the company isn’t making many promises about reliability. but even when it’s final, you’re still looking at a service whose near-term, best-case scenario is being competitive with a solid lte connection. i am no fan of cable companies and wireless carriers, but it’s simply true that my cable broadband and 5g service are both faster and more reliable than starlink, and they will almost certainly remain that way. //

as a whole, the american telecom policy industrial complex has utterly failed to put fiber in the ground and signals in the air at fair prices and with good customer support. so much so that a total science project of an internet access system — which involves huge tradeoffs for scientific research and doesn’t work if there are trees in the way — has captured the attention and imagination of millions.

broadband on the ground is so wrapped up in the lumbering bullshit of monopolistic regulatory capture that it seems easier and more effective to literally launch rockets and try building a network in the sky. starlink isn’t the happy end result of a commitment to “facility-based competition.” it is thousands of middle fingers pointing at us from the air. it is what happens when there is an utter lack of competition.

Northrop Grumman said last week that its Mission Extension Vehicle 2 – a robot spacecraft designed to help prolong the life of satellites in space – successfully docked to a commercial communications satellite. “We are now the only provider of life extension services for satellites,” a company spokesperson said.

SpaceX recently inked a deal with NASA to move any of the company's Starlink internet satellites out of the way if they stray too close to the International Space Station or other agency spacecraft.

The Space Act Agreement, which was signed on March 18, will help maintain and improve space safety, NASA officials said.

SpaceX has launched more than 1,400 of its Starlink broadband satellites to orbit to date. Following the first operational Starlink launch in 2019, the company has tweaked the satellites' design, providing upgrades intended to reduce their reflectivity, enable them to communicate with each other on orbit and even maneuver out of the way if necessary.

‘Red alerts’ of a potential disaster were sent to the companies

By Joey Roulette on April 9, 2021 2:12 pm

Two satellites from the fast-growing constellations of OneWeb and SpaceX’s Starlink dodged a dangerously close approach with one another in orbit last weekend, representatives from the US Space Force and OneWeb said. It’s the first known collision avoidance event for the two rival companies as they race to expand their new broadband-beaming networks in space.

On March 30th, five days after OneWeb launched its latest batch of 36 satellites from Russia, the company received several “red alerts” from the US Space Force’s 18th Space Control Squadron warning of a possible collision with a Starlink satellite. Because OneWeb’s constellation operates in higher orbits around Earth, the company’s satellites must pass through SpaceX’s mesh of Starlink satellites, which orbit at an altitude of roughly 550 km.

One Space Force alert indicated a collision probability of 1.3 percent, with the two satellites coming as close as 190 feet — a dangerously close proximity for satellites in orbit. If satellites collide in orbit, it could cause a cascading disaster that could generate hundreds of pieces of debris and send them on crash courses with other satellites nearby.

The SUV-sized pallet of old batteries is the most massive object the station has ever jettisoned.

The International Space Station got a little lighter last week.

The orbiting lab discarded a 2.9-ton (2.6 metric tons) pallet of used batteries on Thursday morning (March 11) — the most massive object it has ever jettisoned, NASA spokesperson Leah Cheshier told Gizmodo.

The space junk is expected to fall back to Earth in two to four years, agency officials wrote in an update last week. That update also stated that the pallet will burn up "harmlessly in the atmosphere," but not everyone is convinced that's the case.

Given all this, it's completely unclear what problem wooden satellites are meant to solve. Still, the idea of figuring out how to process wood so that it would function in this context is an intriguing materials science problem, and might have some very down-to-earth applications. So, here's to hoping that the project goes ahead regardless.

According to a study last year commissioned by the National Institute of Standards and Technology, GPS has about $1 billion a day in economic impact in the US. Its reach is, simply, mind-blowing.

"Gauging the overall value of GPS is nearly impossible," writes Greg Milner in Pinpoint, a 2016 book about how the space-based system came to be and the effect it's having on the world. "It has become difficult to untangle the worth of GPS from the worth of everything." //

"The timing aspect of this is probably more widely used than the where-are-you aspect," says Goward. //

The origins of GPS stretch back to secret work by the Department of Defense in the 1970s, in a quest for precision targeting. As Milner recounts it, GPS chief architect Brad Parkinson summed up that goal in the phrase "Drop five bombs in the same hole." //

In 1983, after a Korean Air Lines passenger jet strayed into Soviet airspace and got shot down, killing 269 people, President Ronald Reagan declassified GPS to give civilian aircraft access to the navigation signals. Almost a decade later, GPS famously earned its stripes as a military resource during Operation Desert Storm, when it helped guide US and allied forces across desert expanses to a swift victory over Iraq during the Gulf War. //

Though the funding to keep things running goes through the Pentagon -- the Space Force GPS program had a 2020 fiscal year budget of $1.71 billion -- there's civilian oversight as well. The Defense Department and the Transportation Department co-chair the US government's National Executive Committee for Space-Based Positioning, Navigation and Timing, which coordinates GPS-related matters across federal agencies and includes representatives from Boeing, Garmin, Google, Ohio State and Stanford.

Note the keywords in that committee name: positioning, navigation and timing, or PNT. Where you are, where you're going, and when the signals hit a receiver. It's a term that's inescapable when you're talking with folks who live and breathe GPS.

NASA Uses Powerful Supercomputers and AI to Map Earth’s Trees, Discovers Billions of Trees in West African Drylands //

Scientists from NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and international collaborators demonstrated a new method for mapping the location and size of trees growing outside of forests, discovering billions of trees in arid and semi-arid regions and laying the groundwork for more accurate global measurement of carbon storage on land.

According to a non-peer-reviewed paper, Humphreys and Peter Iannucci of the Radionavigation Laboratory state they have determined the Starlink satellites operating in low Earth orbit could provide an 'unjammable' alternative to Global Navigation Services, GPS. "Anticipation is building for commercial broadband Internet services provided by mega-constellations of satellites in low Earth orbit. Such services’ global reach, low latency, and wide bandwith situate them to revolutionize broadband communications. This paper seeks to establish a less-obvious assertion: In addition to broadband service, these constellations could revolutionize satellite-based positioning, navigation, and timing," the paper reads. "Their space vehicles are far nearer and more numerous than those of traditional global navigation satellite systems in medium Earth orbit or geostationary orbit, and their communications transponders have both exceedingly high gain and access to a vast allocation of spectrum."

The paper describes in great technical detail, a system that utilizes the Starlink satellites working alongside traditional GPS signals to deliver precise location signals more accurate and faster than current GPS. Read the research paper published by the University of Texas at Austin: Fused Low Earth Orbit Global Navigation Satellite Systems

The OGO-1 geophysics satellite's long space odyssey is nearly at an end.

The space-faring firm has been inviting consumers to sign up for its Uber-like ridesharing service. //

On Wednesday, the space-faring firm announced via Twitter that over 100 spacecraft have signed up to use the service:

"More than 100 spacecraft have been signed up to fly on Falcon 9 since we launched the rideshare program. Small satellite operators can book their ride to orbit online"
The landmark, which comes fewer than seven days after its first ridesharing mission debuted, suggests the program has received a warm reception. SpaceX first announced the SmallSat Rideshare Program back in August 2019, as a way of sending up payloads on other missions rather than scheduling an entire mission just for one payload. Think of something like UberPool, where the firm groups together suitable passengers, and that gives a good approximation.

SpaceX’s Starlink satellite constellation is still deep into testing mode, but engineers say it’s already relaying 5 trillion bytes of data on a daily basis.