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Starman — the dummy riding a cherry-red Tesla Roadster through space — has made his closest approach ever to Mars.
'Challenger: The Final Flight' successfully tackles the anticipation, tragedy, and recovery involving the defining national event of a generation. //
“It was a totally clear sky…it was ‘Mars to CAVU,’ as we used to say, ‘clear and visibility unlimited.’ It was just a beautiful day,” recounts William Harwood, the longtime Cape Canaveral bureau chief for United Press International. “It was just very cold.”
On Jan. 28, 1986, after crews had finished scrapping off hundreds of giant icicles that had formed the night before, and following two days of scrubbed launches, the 25th flight of the United States Space Shuttle Program was finally cleared to go.
Onboard the shuttle Challenger were astronauts Ronald McNair, Ellison Onizuka, Judy Resnik, Francis Richard Scobee, Michael Smith, payload specialist Gregory Jarvis, and Christa McAuliffe — a social studies teacher hailing from Concord High School in New Hampshire and set to be the first civilian in space.
Unknown to the crew of the Challenger, it would be the last mission of the spacecraft. Just 73 seconds into the flight, at an altitude of approximately 46,000 feet, it was over.
They were all gone.
Comprising four episodes and a combined three hours, Netflix’s new documentary, “Challenger: The Final Flight,” successfully tackles the anticipation, tragedy, and recovery involving one of the defining events of national mourning between the assassination of J.F.K. and 9/11.
In a period where much of the output from Hollywood is either uninspired or, conversely, overburdened — and frequently ruined — by the desire to shock audiences by being overly brazen or bizarre, in many respects, what Abrams and his team have produced feels akin to their source material: the product of a bygone era.
True, the cinematography benefits from the latest digital technology, and the score feels more nuanced and authentic than something that would have been composed a generation earlier, but everything else about the production feels refreshingly familiar, albeit with a 2020 up-gloss. //
Ultimately, “Challenger: The Final Fight” is an incredibly pro-life documentary; not in the sense of being anti-abortion, but in the authentic and moving ways it pays tribute to the seven lives that were lost that cold January day 34 years ago. At the end of the miniseries, few viewers will be lamenting the $3.2 billion cost of the disaster — they’ll be left saddened, sore, and shaking their heads at the wholly unnecessary deaths of the brave Americans who boarded the final flight of the Space Shuttle Challenger.
The Europa Clipper is poised to be one of the most important vessels in the history of exploration — if only government largesse would get out of the way. //
There’s only one problem: today, it’s illegal for it to be taken to space via any existing launch vehicle. The Europa Clipper has been dosed with a poison pill of pork which has endangered the entire mission. //
While a swelling trend of privatization is sweeping space exploration and leading to billions in savings, the Clipper has been legally forbidden from being launched on a private rocket. Quietly slipped into page 129 of a bloated omnibus spending bill from 2016 is a legal requirement that the Clipper can only take to space if it is on the Space Launch System.
The Space Launch System, or SLS, is a $28 billion government rocket program intended to replace the extinct shuttle program. It’s now billions over budget, and after nearly a decade of development still only exists in the imaginations of artists and politicians.
No other NASA mission in history has been forbidden by force of law from using a private rocket. The negative consequences of this law, however, are immense.
More than 20 years after its introduction, the EmDrive is still being tested in labs around the world, including DARPA. But the controversial thruster's do-or-die moment is quickly approaching.
The OGO-1 geophysics satellite's long space odyssey is nearly at an end.
In 2015, Oak Ridge National Laboratory produced the first plutonium fuel in the US in nearly 30 years. Now it’s headed to another planet. //
At the heart of Perseverance is a small “nuclear battery” the size of a beer keg called a radioisotope thermoelectric generator, or RTG. Unlike the nuclear reactors that create electricity on Earth, RTGs don’t have to initiate or sustain a fission reaction to generate power. They don’t even have any moving parts. Instead, they passively harvest the natural heat produced by the decay of plutonium-238 and convert it into electricity. They can reliably provide energy and heat to a spacecraft for decades—the two plutonium-powered Voyager probes launched in the late 1970s are still transmitting from interstellar space—and have been NASA’s go-to power source for more than two dozen deep-space missions.
“Plutonium-238 is a unique isotope of plutonium that principally decays by alpha radiation, and because of that, it generates a lot of heat,” says Robert Wham, the plutonium supply program manager at Oak Ridge National Laboratory, which is now responsible for making the stuff for NASA. “For a small spacecraft like Perseverance, you don’t want fission power. You just want thermal decay.” //
When the US got out of the plutonium business, it left NASA with a cache of a few dozen kilograms of plutonium-238 to ration for all future missions. It wasn’t much; the Perseverance rover alone uses nearly 5 kilograms of plutonium. At some point, this stockpile was bound to run out; a 2009 report by the National Academy of Sciences predicted that the US had only enough plutonium for a few more deep-space missions. That left the US with a few unpalatable options: Abandon exploration of the outer solar system, purchase plutonium from abroad, or start making it again domestically. //
With concerns about a plutonium shortage mounting—Russia was also running low—NASA policymakers decided the agency would foot the bill on its own. And since 2011, NASA has borne almost the entire cost of producing plutonium at the Department of Energy’s Oak Ridge National Laboratory in Tennessee. The investment soon paid off. By 2015, chemists at Oak Ridge produced the first sample of plutonium-238 in the US in nearly 30 years. At the same time, the lab invested heavily in automated production systems that would allow it to produce enough plutonium to meet NASA’s future needs. //
The process starts when researchers at Idaho National Lab send neptunium-237, itself a radioactive metallic oxide, to Tennessee, where automated machines press it into pellets the size of pencil erasers. Next, 52 of these pellets are stacked into metal rods called targets and placed in a nuclear reactor at either Oak Ridge or Idaho National Lab, where they are bombarded with neutrons to produce plutonium. After it’s left to cool for a few months, the plutonium is shipped to Los Alamos National Laboratory in New Mexico, where another machine presses the small plutonium pellets to form larger ones the size of marshmallows. Then they’re ensconced in a casing made out of iridium, a virtually indestructible metal that would prevent radioactive contamination in case of an accident when the rover is launched. Finally, the armored plutonium is shipped to Idaho National Lab, where 32 pellets are loaded into the rover’s nuclear battery before it’s installed on the vehicle.
Today, Oak Ridge is only producing about half of its target of 3.5 pounds of plutonium a year, a milestone Wham and his colleagues plan to hit by the mid-2020s.
Why is it the most energy efficient to change orbit inclination while crossing the equator?
Specifically, it's most efficient to do a plane change at one of the two "nodes" where the origin orbital plane intersects the destination plane. ANASIS-II is destined for geostationary orbit, so its destination plane is the plane of the equator.
Any orbit around a single massive body lies in a single plane. It should be clear that you can't enter an equatorial-plane orbit at any point except a point directly over the equator. Coming from any non-equatorial orbit, there are two points on the orbit where the planes intersect. If you try and do a burn to enter a particular destination orbit from anywhere else, you just push the intersection point a little further around the orbit.
(It's super easy to demonstrate this in Kerbal Space Program, but kind of hard to put into words!) //
A great aid to intuition is to remember one principle about orbit changes: if the engine is off, the orbiter always returns to same point one orbit later.
So for any orbit change, if you want to do only a short burn, it has to be at a point that is common for both the current orbit and the destination orbit. This applies to inclination changes, altitude changes and basically any orbit change. If the orbits do not have a common point, the change requires two burns and an intermediate orbit, such as Hohmann transfer orbit.
Like Russell's answer details, for a geostationary target orbit those common points are always above equator. For e.g. polar target orbit, the points would be somewhere else.
Finally we talk about the important part about space travel: pooping.
Was there a backup plan in case the Shuttle toilet malfunctioned?
What was the plan in case the Space Shuttle toilet malfunctioned? How were the astronauts expected to then handle their waste? Did they carry Apollo-style fecal collection assemblies (poop bags)? Or did they just have extra fecal containment systems (diapers)? //
According to Scott Manley, they did indeed carry Apollo-style poop bags. But those were so distasteful that a mission could be scrubbed if that was all they had to rely on. youtube.com/watch?v=w5y0mTqK54k – Greg Jun 24 at 17:41 //
Some non-catastrophic failures of the WCS could be worked around.
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Mechanical failures of the commode control handle or linkage could be worked around using procedures in the In-flight Maintenance Checklist. //
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Finally, if both fan/separators were failed, urinal operations could be recovered by connecting the urinal hose directly to the waste water overboard dump system. However, this resulted in a direct connection from the crewmember to vacuum, and the procedure contained this immortal warning.
WARNING: Urinal connected to vacuum. Allow for airflow. Do not 'Hard Dock' w/Urinal Funnel. Physical injury possible.
(From In Flight Maintenance Checklist section W, not currently online) //
NASA seem to like sneaking dry jokes into their technical documentation, and the euphemistic use of the term "hard dock" is perhaps my new favourite example. – anaximander Jun 23 at 16:10
@GdD early on there were lots of problems. The original version included a "slinger" - yes, the feces was supposed to hit the fan - and that liked to fail. A search through the Shuttle Missions Summary for 'wcs' turns up many examples. https://spaceflight.nasa.gov/outreach/SignificantIncidents/assets/space-shuttle-missions-summary.pdf Feel free to ask a followup for details. – Organic Marble Jun 23 at 16:21 //
[do] We have a badge for know your sh**? – Anthony Stevens Jun 23 at 18:42
Next on English.SE: when feces not hitting the fan is the cause of your problem, does the expression "when shit hits the fan" still apply? – Mast Jun 24 at 7:00
This is why regular space tourism is still a long way off. Training your average Joe and Jane Hawaiian-shirt wearing sightseers how to properly use the space-commodes is probably unlikely to work at scale any time soon. – Darrel Hoffman Jun 25 at 13:55
There are no smells in vacuum—but recycled air in an orbiter is another story.
The idea of a human colony on Titan, a moon of Saturn, might sound crazy. Its temperature hovers at nearly 300° below zero Fahrenheit, and its skies rain methane and ethane that flow into hydrocarbon seas. Nevertheless, Titan could be the only place in the solar system where it makes sense to build a permanent, self-sufficient human settlement. //
But although the Moon and Mars look like comparatively reasonable destinations, they also have a deal-breaking problem. Neither is protected by a magnetosphere or atmosphere. Galactic Cosmic Rays, the energetic particles from distant supernovae, bombard the surfaces of the Moon and Mars, and people can’t live long-term under the assault of GCRs. //
GCRs include particles such as iron nuclei traveling at close to the speed of light that destroy brain tissue. //
On Earth, we are shielded from GCRs by water in the atmosphere. But it takes two meters of water to block half of the GCRs present in unprotected space. Practically, a Moon or Mars settlement would have to be built underground to be safe from this radiation.
Underground shelter is hard to build and not flexible or easy to expand. Settlers would need enormous excavations for room to supply all their needs for food, manufacturing and daily life. We ask why they would go to that trouble. We can live underground on Earth. What’s the advantage to doing so on Mars? //
Titan is the only other body in the solar system with liquid on the surface, with its lakes of methane and ethane that look startlingly like water bodies on Earth. It rains methane on Titan, occasionally filling swamps. Dunes of solid hydrocarbons look remarkably like Earth’s sand dunes.
For protection from radiation, Titan has a nitrogen atmosphere 50 percent thicker than Earth’s. Saturn’s magnetosphere also provides shelter. On the surface, vast quantities of hydrocarbons in solid and liquid form lie ready to be used for energy. Although the atmosphere lacks oxygen, water ice just below the surface could be used to provide oxygen for breathing and to combust hydrocarbons as fuel.
It’s cold on Titan, at -180°C (-291°F), but thanks to its thick atmosphere, residents wouldn’t need pressure suits—just warm clothing and respirators. Housing could be made of plastic produced from the unlimited resources harvested on the surface, and could consist of domes inflated by warm oxygen and nitrogen. The ease of construction would allow huge indoor spaces.
Titanians (as we call them) wouldn’t have to spend all their time inside. The recreational opportunities on Titan are unique. For example, you could fly. The weak gravity—similar to the Moon’s—combined with the thick atmosphere would allow individuals to aviate with wings on their backs. If the wings fall off, no worry, landing will be easy. Terminal velocity on Titan is a tenth that found on the Earth.
It's not as crazy as it sounds. //
In the March 1988 issue of Popular Mechanics, sci-fi author Isaac Asimov proposed building a particle accelerator on the moon.
A physicist recently revisited the idea in a paper published to the preprint website arXiv.org.
The moon, it turns out, might actually be a perfect place to put one. //
Asimov envisioned the year 2028. Humans—or Lunarians, as he called them—are thriving on the moon. They've erected a massive radio telescope on the moon’s far side and have built research stations, factories, and celestial observatories, all powered by nuclear and solar energy.
The moon, Asimov mused, is the ideal scientific laboratory, one that could help us unravel the mysteries of particle physics. "Turning to the heavens, special detectors would analyze rays from astrophysical sources, and moon-based particle accelerators would give new insight into the nature of matter," he wrote.
“I've done crazier things than dry out a radio antenna.” //
Demo-2, the first orbital human spaceflight to launch from the United States since NASA's space shuttle fleet retired in 2011, is a joint SpaceX-NASA effort. The company holds a $2.6 billion contract with NASA's Commercial Crew Program to fly six operational crewed missions to the ISS, and Demo-2 is designed to fully validate Crew Dragon and the Falcon 9 for those flights. //
Approximately two-thirds of the global launch market is effectively closed to competition because these are national payloads. For example, Russia and other space-faring countries will typically launch their military and science satellites on domestic rockets. Only about one-third of the overall launch market—consisting of satellite constellations, communications and imaging satellites for nations without launch programs, and other payloads—is truly open to competition.
Decades ago, US launch companies ceded this commercial market as they began to focus on winning more lucrative contracts to launch payloads for the US military. By 2006, when Boeing and Lockheed Martin consolidated their rocket businesses into a single company, United Launch Alliance, America essentially captured zero percent of the competitive launch market. Customers in the United States and abroad turned to more economical launchers in Europe, Russia, and elsewhere to reach orbit. Meanwhile, with a monopoly on launching missions for NASA and the US Department of Defense, United Launch Alliance’s prices steadily rose.
The success of the Falcon 9 rocket reversed this trend dramatically. Seeking lower cost delivery of supplies to the International Space Station, NASA invested $396 million in SpaceX from 2006 to 2010 to develop its Cargo Dragon spacecraft, the Falcon 9 rocket, and a launch pad at the Cape. This investment, which precipitated the June 4, 2010 launch from Florida, delivered not just value for NASA, but for the country. //
“Because of the investments that NASA has made into SpaceX we now have, the United States of America now has about 70 percent of the commercial launch market,” said the space agency’s administrator, Jim Bridenstine. “That is a big change from 2012 when we had exactly zero percent.” //
Most visibly, the company demonstrated reuse of the first stage booster. On its very next mission following the CRS-7 failure, in fact, SpaceX landed a Falcon 9 first stage for the first time. The next April, the company nailed its first drone ship landing. Then, in March 2017, the company successfully re-flew a Falcon 9 first stage for the first time. In the three years since, SpaceX has landed more than 50 rockets and flown the same booster five or more times.
Carissa Christensen, founder of Bryce Space and Technology, an analytics firm, said the reuse of vertically launched and landed rockets had been discussed in the aerospace community for decades. "This was always something that would make a difference, and it was desirable, but it never happened," she said. "Then SpaceX made it happen."
Moreover, she said, the company did this on its own initiative. Typically in spaceflight, a government agency will offer a contract for some type of project and pick a contractor to do the work. Although SpaceX received a substantial amount of NASA funding for cargo and crew delivery to the space station, it got no money for reuse. Instead, Christensen said, the company invested its own funds to clear a "very, very high" technical hurdle that others had aspired to. In return for chancing its own funds on reuse, SpaceX now has the world's only reusable, orbital rocket, and it has just furthered its ability to dominate the commercial satellite market. //
"It's clear that the space industry is on a path toward next-generation launch vehicles," she said. "But SpaceX is 10 years ahead of those next-generation launch vehicles. SpaceX had its first launch of its next-generation launch vehicle 10 years ago." The world of launch, she marveled, has tilted almost beyond recognition from a decade ago. Then, SpaceX was the upstart. Now the Falcon 9 is considered the old, reliable launch vehicle. //
An astronaut on the International Space Station snapped an image of NASA's Kennedy Space Center in Florida showing the SpaceX Demo-2 rocket and capsule just a day before the mission's scheduled launch.
FLORIDA TODAY photographer's photo of crowd leaving Titusville bridge after SpaceX launch scrub got everyone's attention, albeit for different reasons.
Going forward, U.S. space exploration will be mostly done by the private sector, that is, if we wish to retain our lead @teamcavuto //
Cavuto had to throw cold water on the excitement. With no less than 5 of his guests, he insisted on asking, “What do you think about private companies taking the lead in space flight?” His tone and tenor implied that this was a bad thing—something wrong. //
Well, Mr. Cavuto, private enterprise has been at the forefront of aviation since its beginnings here in these United States. When the Wright Brothers took their famous flight, they were not employees of the Federal Government. Robert Goddard, long looked at as one of the pioneers of American rocketry, was a private citizen, funded mostly by private organizations. Throughout the rise of first aviation and then rocketry, private citizens, either alone or in private companies, were leading the charge on new discoveries and technological innovation.
One major exception to this, was when NACA/NASA was given the mission to beat the Soviets into space and thence to the Moon. Indeed, many of the researchers and designers were federal employees. But that was a crash program and itself an aberration. //
One tool that enabled this private sector innovation was the use of prize money or private sponsorships. In aviation, prize money, either from private donations or even sometimes from government, was quite commonly used to incentivize the private sector to solve a technological problem. Here is a clip from the December 1947 issue of Flying Magazine. Note the public-private partnership and use of prize money. //
Our education system is sadly failing our citizens. The fact that one of the lead anchors on an allegedly center-right news organization looks at a privately-led exploration effort in space and considers that not only some sort of aberration, but implies that there is something wrong with it, bothers me. It’s an insult to explorers and innovators like Drake, Cook, Shackleton, Goddard, Frank, and Orville Wright, to name but a few. Mr. Cavuto, it’s NASA that is the aberration, not Space-X.
Private industries have helped drop the cost of launching rockets, satellites and other equipment into space to historic lows. That has boosted interest in developing space—both for mining raw materials such as silicon for solar panels and oxygen for rocket fuel, as well as potentially relocating polluting industries off the Earth. But the rules are not clear about who would profit if, for instance, a U.S. company like SpaceX colonized Mars or established a moon base.
At nearly 20 tons, the Long March 5B is the largest space vehicle to re-enter Earth’s atmosphere uncontrolled since Soviet Salyut in 1991. //
The Chinese communist regime is a box of surprises — bad ones. We have not yet recovered from the coronavirus pandemic they caused, and they have already exposed us to another huge risk. At 11:33 a.m. on May 11, a gigantic, out-of-control space object crossed the atmosphere and fell into the Atlantic Ocean, showering debris over several villages on the Ivory Coast.
It even crashed into a family’s house, not causing casualties but spreading panic throughout the area. Just 15 minutes earlier, it had flown over New York, threatening the country’s most populated city with a space massacre.
It was not a mistake, nor a mission failure. Quite simply, the Chinese Communist Party (CCP) continues to completely disregard human lives. In fact, it considers the mission to have been “a great success.”
What plummeted to Earth was the wreckage of the Long March 5B rocket, launched May 5 from the Wenchang Space Launch Center. According to the calculations of Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics who has followed this event in detail, it weighed about 20 tons and is the largest space vehicle to fall out of control to Earth since the Soviet space station Salyut, which crashed in Argentina in 1991.
The crash of Long March 5B was closely followed by the U.S. Space Force’s 18th Space Control Squadron, which monitors space debris from Vandenberg Air Force Base in California. The official Chinese story rambles on about the mission’s success and the extraordinary separation between the rocket and its cargo 488 seconds after takeoff, but does not say a word about what happened next. //
Despite its enormous size, however, the rocket did not have a second stage to control of the central part of the vehicle after launch. In other words, China had planned only for the launch. It hadn’t provided any information about the craft’s re-entry to Earth, nor did it have a plan to bring it down safely.
If the Long March were a small rocket, it would have disintegrated when it passed through the atmosphere, but a 176-foot-tall rocket with 10 engines does not completely disintegrate on re-entry. For the sake of comparison, the impending fall of the Chinese space station Tiangong-1 rocked the world in 2018, and it weighed only eight tons. Long March 5B weighs more than double that. Even if atmospheric shock broke it into a million pieces, it would still pose a serious danger if it fell into populated areas.
Following the first reports received from the Ivory Coast last Tuesday night about engine parts falling over several villages in the country, it has been confirmed they are remnants of the Chinese rocket. Local media say it is a miracle that the shower of pipes and engine parts has not caused any casualties, as far as we know. //
China repeatedly fails to comply with rocket-launch regulations, as it sends the crafts off from populated areas. Last year, during the launch of Long March 3B, its first stage fell in the vicinity, destroying several houses and contaminating the area with highly toxic fuel residues. Although the Chinese government veils any technological failures in absolute secrecy, Western sources consider that hundreds of people could have died.
As usual, the CCP’s propaganda machine littered social networks with two surprising statements impossible to prove: that the people were evacuated before the crash and that the owners of the destroyed houses were happy because the regime would give them new houses.
Based on the preliminary radio elset, OTV 6 appears to have been inserted into a 45-degree inclined orbit at ~390 km altitude. The ground track repeats every 3 days:
Jonathan McDowell
@planet4589
·
May 12
Reports of a 12-m-long object crashing into the village of Mahounou in Cote d'Ivoire. It's directly on the CZ-5B reentry track, 2100 km downrange from the Space-Track reentry location. Possible that part of the stage could have sliced through the atmo that far (photo: Aminata24)
Operating a mission is a labyrinthian process from start to finish, with all kinds of checks and fail-safes along the way.