Posts by cray74

SpaceX's Starship explodes again ... while still on the ground

Re: Return Journey

Since any human launched to Mars in 2028 will be dead of radiation sickness within a year

Rounding up to 2mSv per day during flight in an unshielded spacecraft and 2mSv per day on the surface of Mars in an unshielded spacecraft, you'd get 730mSv in a year (73 rem, if you prefer). At 1Sv, you have a 5.5% chance of developing cancer in your remaining decades of life, assuming the disputed linear no-threshold model is used. Generally, serious radiation sickness develops around 500 rem / 5 Sv if the dose is received in a short period.

Shielding is rather straightforward. On the Martian surface, a few meters of regolith will screen out those cosmic rays. Around 40cm of hydrogen-rich materials like water, plastic, liquid methane, or feces would significantly cut the radiation dose during the flight.

UK dumps £2.5 billion into fusion pipe dream that's already cost millions

Reaction engines derived from a stupid idea (HOTOL) in the first place.

Agreed. Single-stage-to-orbit vehicles like Skylon are extremely sensitive to the mass that's carried to orbit, and SABRE attempted to save weight in an area that adds little to the orbited mass: oxidizer.

Oxidizers are dense, so you can store a lot of oxidizer mass in a small, relatively low pressure, relatively low mass tank. (Compare the US shuttle's external tank's hydrogen tank to its oxygen tank.) Further, pretty much all the oxidizer goes out the tailpipe by the time you reach orbit, so an SSTO isn't lugging a lot of dead oxidizer mass with it.

SABRE attempted to lower that oxidizer mass but required additional mass be carried to orbit:

1. An elongated, aerodynamic, lifting form with less mass efficiency for its volume than a chunky SSTO like, say, Kankoh Maru

2. More heat shielding for extended hypersonic airbreathing flight

3. Less mass-efficient engines; hydrogen-oxygen rockets can approach 100:1 and kerosene-oxygen rockets are operating at 184:1, while SABRE managed about 14:1

Further, SABRE would impose higher gravity and drag losses during ascent because it required more time messing around in the atmosphere. It would therefore need more delta-V (fuel to change velocity) than a purely rocket SSTO with higher acceleration.

SABRE has a very high specific impulse, but it achieved that by not carrying oxidizer for part of the flight. In the end, that's not a great place to save mass.

Skylon was a sexy beast and SABRE had a lot of cool engineering (literally), but they were trying to solve the wrong SSTO problems.

Re: @juice

But there's plenty of thorium

There is plenty of thorium, but you don't put thorium into a reactor and get power out. You put thorium-232 into a reactor, bombard it with neutrons until it turns into protactinum-233, which hopefully decays into uranium-233 without picking up additional neutrons during its rather long (27-day) half-life, then do the fuel processing needed to extract uranium-233, and finally fuel a reactor with the U-233.

Shippingport needed 5 years to increase its U233 inventory by 1.4%. Thermal breeder thorium-uranium cycles are looking at breeding factor of 1.01 to 1.02, which means there's a doubling period of decades. In other words, it'd be a rather slow process to get the nuclear industry running on bred U233.

The good news is, most light water reactors can run on U233 and handle thorium-U233 fuel pellets. They might not make breakeven when it comes to generating fuel, but you don't need exotic new reactors to run on U233.

Besides lithium, there are also deuterium and boron bombardment routes to tritium production. Both are non-trivial sources of tritium in fission reactors; CANDU reactors generate kilograms of tritium annually from their heavy water.

As for radioactive waste, deuterium-tritium fusion reactions produce about 100x the neutron flux of a pressurized water fission reactor. Design of fusion reactors intended to have long life times (like ITER) need careful attention to neutron activation in reactor materials. Ideally, all the resulting isotopes will have short life times.

Pentagon needs China's rare earths, Beijing just put them behind a permit wall. Oops

Re: Trump administration should have...

The issue of China's production of REEs has been know about for ages, but no one did anything about it.

The aerospace programs I work on have been eliminating Chinese-sourced REEs since 2021, though they're modest users. The last US administration had been pushing that elimination, which got my C-suite bosses to listen and authorize program efforts, and Biden was helping get the Mountain Pass mine up and running.

I wouldn't be surprised if DOGE cut Mountain Pass's defense funding, though. They don't seem to look before snipping unless their target is someone who regulates Elon.

Nuclear center must replace roof on 70-year-old lab so it can process radioactive waste

Re: Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. Etc...

Most of the isotopes that are dangerous for tens of thousands or millions of years are transuranics that make good nuclear fuel with a bit of reprocessing. Rather than launching them on large, explosion-prone vehicles, it might be more useful to destroy the long-lived wastes as fuel in nuclear reactors on Earth.

Weeks with a BBC Micro? Good enough to fix a mainframe, apparently

Re: Typing Pools...

Sometimes typo tolerance is high. My prior employer was an R&D firm that basically delivered reports to research groups in the US military, which were staffed and led by doctorates. My annual reviews included goals like "number of typos per report" because the customers were smart, educated, and were of the opinion they were paying fortunes for pieces of paper.

On the other hand, my current employer recently issued a company history book (to the effect of "100 years of engineering successes") and the introduction page was littered with typos. Most of my engineering reports are email summaries where no one cares about typos. Instead, they just want the factory's problem to get fixed as fast as possible.

SpaceX loses a Falcon 9 booster and scrubs a Starship

Hence the spin sections. Asteroids, with negligible gravity, are better hosts for spinning habitats than low-to-mid-gravity environments like Luna and Mars. In the latter cases, you need awkwardly tilted floors that deliver variable "gravity" across the floor.

With an asteroid, you can almost ignore the gravity and arrange a spinning habitat - torus, cylinder, can on a string - however you like. Plus, asteroids tend to be rich in carbon and water, unlike the moon, and have easily excavated regolith for radiation shielding.

As you rightly point out the lack of a magnetic field (how much power would it take to generate an earth like magnetic field with a big copper wire laid around the equator?) means that solar wind has stripped much of the atmosphere away, and would do so again.

I wouldn't worry about the magnetic field. Mars' gravity is high enough to retain an Earth-like atmosphere for geological time scales (100 million-ish years, give a billion or take 99 million), and terraforming only makes sense as a luxury project for highly productive space-based civilizations. If the atmosphere gets a bit thin, then their great great grand clone-uploads can replace the lost nitrogen from Titan's and Venus's boundless nitrogen reserves.

Not that I'd vote for terraforming Mars. The real estate and accessible resources are limited compared to asteroids.

Speaking more generally about space colonization than just Mars, as the saying (well, T-shirt) indicates it's not wise to keep all of a species' eggs in one basket.

Personally, I wouldn't start with Mars. The impact of the long travel time on logistics would be a hindrance compared to, say, lunar settlements. Or if you're willing to go as far as Mars then you might as well head to the asteroids, which have the same resources (water, metals, minerals) but avoid the burden of deep gravity wells.

France tops China’s tokamak record with 22-minute plasma containment run

Re: Still In the Steampunk Era

Your song needs a verse that praises its use in bushings and bearings if it's going to chart.

I was thinking about it since the place I most recently used bronze was a linear plain bearing. Bronze allowed us to get rid of a recirculating linear bearing that had been crapping millimeter-scale ball bearings into some optics and their motors. But "pumps and propulsors" popped into my head first.

Re: Still In the Steampunk Era

Oh great, the world's greatest scientists still cannot concieve of an energy generation system that doesn't require heating water to produce steam.

I once encountered a fellow who was deriding bronze as an old and primitive material. He did not like my description of modern bronzes and their exceptional performance in assorted modern applications ranging from pumps to propulsors, nor pointing out that some bronzes had tensile strengths rivaling that of the strongest titanium alloys. Generally, the thinking on his part seemed to be that because bronze came in ye olden times before the modern iron-and-steel age, bronze was primitive and unworthy of consideration.

As others have noted, water has exceptional features for power generation. Sure, the oldest electrical generating power stations boiled water to generate electricity, but does the longer history of water in power generation mean that there's something fundamentally wrong with boiling water for electricity?

Look at nuclear power plants: yes, they're boiling water, but water is also performing numerous critical functions beyond cooling and driving turbines. Water is moderating the nuclear reactions, and there are few moderators so convenient as water. (Graphite: burns, isn't a coolant, has its own cooling problems.) Water doesn't mind radiolysis; it is easily recombined unlike, say, organic coolants, which turn into sludge and shutdown reactors. Water is a self-regulating buffer against power fluctuations that gaseous coolants (helium, nitrogen, carbon dioxide) can't match. Water has convenient phase changes that not only allow reactor regulation but also means problems like "freezing solid" (lead, lead-bismuth) aren't an issue. While water isn't the most innocuous chemical, it presents less of a headache than some coolants (sodium, sodium-potassium). Water's just great stuff for getting electricity out of fission reactions.

Water answers a lot of problems for fusion reactors, too. Why is that a bad thing?

Re: "heating gases under enormous pressure"

I don't know what plasma pressure CEA West achieved, but ITER is expected to run at about 2.6 atmospheres of pressure in its plasma, while MIT's Alcator C-Mod achieved 2.05 atmospheres in 2016.

I have found that CEA West's diverters are cooled with water at 30 bars pressure, but that should have little to do with plasma pressure unless there's a leak and nascent Stackpole event. So, rampant speculation: since CEA West is meant to inform ITER's design and operation, it's plasma pressure is in the 1 to 2 atmosphere range. (I have found a nice article on CEA West's vacuum pumping system when it was "Tore Supra," but the vacuum pressure between the plasma and the plasma-facing components when it was a graphite-lined reactor isn't quite answering the question.)

Einstein Probe finds two stars that have spent 40 million years taking turns eating each other

Re: Title sounds like a NSFW celebrity leak

Upon reading the title, my thought was, "Well, as one does in a good long-term partnership."

RIP Raymond Bird: Designer of UK's first mass-produced business computer dies aged 101

Re: Computers in the 1950s

I can't imagine that a device with 1000 valves would set any records for uptime.

The original Semi-Automatic Ground Environment (SAGE) air defense computers had 49,000 valves (or 60,000 to 80,000, by another reference) and an average annual maintenance downtime of 3.77 hours per year. This was achieved by making the computers duplex - one half was almost certainly running while moths were being fished out of the valves of the other.

SAGE's reliability was also helped by improving the valves. Reliability of the valves was increased from 500 to 500,000 hours by methodically tackling failure points in valve manufacture. Finally, SAGE had a diagnostic system for identifying tubes that were drifting toward failure, which allowed repairs before the hardware failed.

Diversity, equity, and inclusion is not an illusion, but it soon might be

Re: Seems to match

"unconscious bias" - like every other new idea in the pseudoscience of psychology from the last 40 years - has been debunked.

If it's not 'unconscious bias' that results in equally-or-better qualified women and candidates of color getting excluded in favor of white men, what is it? Conscious racism and sexism?

NASA’s radiation tolerant computer lives up to its name after surviving Van Allen belts

Re: Slice of bread standards

Depending on the destination and launch window, passage through the van Allen Belts can be minimized or avoided. Crewed Apollo flights skimmed the low energy fringes while insisting the crews stay in the relatively thick-skinned command module for the Belt transit. Interplanetary probes could use the same technique. It seems like Blue Ghost was more deliberate in targeting the high-energy core of the belts.

NASA solar mission data recovering after server room flood fiasco

SpaceX is a launch company and rocket builder. It lacks the labs and scientific personnel to carry out NASA's assorted programs, just as NASA lacks the rocket factory and industrial capabilities to replace SpaceX.

London has 400 GW of grid requests holding up datacenter builds

400GW?

In 2023, the UK used an average of 33.4GW of electricity, with a peak demand of 52.7GW and a total installed capacity of 74.8GW. 400GW of proposed projects is similar to the US's average demand.

Did a decimal slip somewhere in the report from Ofgem?

NASA spacewalkers to swab the ISS for microbial life

Re: LA Fires

So LA burns but the priority for the boffins in the US is a manned mission to Mars. Priorities eh?

Did you also think that someone with a doctorate in English literature should've been relieving overworked doctors in hospitals during COVID's peak?

The boffins who design aerospace hardware and missions have little to do with firefighting and wild fire risk.

Jimmy Carter set the solar, space, and environmental pace

Re: He was one of us

If Carter avoided supply-sided economics then the US dodged a bullet - the 1970s US economy was bad, but embracing voodoo economics would've made it worse.

Have supply-side economics ever worked?

InSight data suggests plentiful water lies beneath Mars' surface

Other water sources

A scientific base or colony on Mars has a lot of water options besides "drilling ridiculously deep into the crust." Hydrogen-rich soils indicative of water show that permafrost is widespread and shallow. The north pole has plenty of water ice. Korolev crater has 2,200 cubic kilometers of water.

For terraforming, depending on water soaked deep into the Martian crust seems like a bad plan since it could reasonably soak back into the crust. To create enough water to fill Mars' north polar water basin (a nice ocean to sustain a water cycle) and saturate the crust, you'd want about a Ceres-sized volume of water, which is a bit beyond the "smash a couple of comets into Mars and nuke the poles" of Muskian thinking. And you need a rich source of carbon and nitrogen for the atmosphere and ecosphere, something on the scale of strip-mining continental masses of ice crust and the atmosphere from Titan. Which sort of points to the dead-end nature of terraforming: it's a luxury project for post-scarcity interplanetary civilizations. Start with settling the belt and leave terraforming for latter day kajillionaires.

French internet cables cut in act of sabotage that caused outages across country

Re: Transport technologies

Show me your numbers.

Addressing Anonymous Coward's claim that the far right is more involved in terrorist activities than the far left:

The far right and religious extremists have been involved in far more violent attacks, particularly lethal ones, than the far left. Or as the link puts it:

"However, although there was a historically high level of both far-right and far-left terrorist attacks in 2021, violent far-right incidents were significantly more likely to be lethal, both in terms of weapon choice and number of resulting fatalities. ... Of the 30 [terrorist] fatalities in 2021, 28 resulted from far-right terrorist attacks. "

That's a US study on US attacks, current only through 2021, and it does not address economic impact as monetary costs did not seem to be AC's point.

Curiosity rover is crushing it: Ran over a rock and found pure sulfur

Re: Well...

Every scene now I'm going to be under the assumption that it is just extremely stinky on Mars...

The elemental sulfur that Curiosity found is scentless. It's the sulfur oxides, hydrides, and mercaptans that will stink up the place.

CrowdStrike file update bricks Windows machines around the world

Re: Apparently affecting MS worldwide.

How are kids supposed to pay?

You know that pained look kids give when they receive a present they didn't really want and won't use, but know they're supposed to be fake happiness to the gift giver? I got that from my nieces the last time I gave them cash for Christmas. (They asked for money over toys, books, or anything else, so I carefully got some fresh bills from a live bank teller, dropped them in funny greetings cards, and waited for beaming faces on Christmas morning.)

As my sister-in-law patiently explained to me, cash isn't useful to kids now. They can't pay for online games with cash, exchange cash with friends by phone, buy stuff online with cash, pay for Door Dash to deliver a Starbucks in the morning with cash, or any other modern activity.

So: prepaid gift cards. Digital currency makes the kids happy.

SpaceX's Falcon anomaly could have serious implications for the space industry

Re: Starliner rescue?

The problems occurred during an engine relight. Missions to the ISS do not require this.

Does the Dragon use its own engines for the circularization burn, or does SpaceX use an unusual direct flight plan to the ISS? Traditionally, second stages fire ~45 minutes into flight for circularization. (In SpaceX's case, the second stage would fire a third time to de-orbit the stage after capsule separation.)

Is Russia using Starlink in Ukraine? Congress demands answers

Re: Should be (relatively) simple...

I'm still puzzled why Congress is making such a big deal out of this given Russia doesn't exactly need Starlink.

Russia's invasion revealed a lack of decent communications systems in its military. Russia has spent the last 30 years developing advanced military technology but didn't follow through in deployment, allegedly because deployment funds went into the pockets of Putin's associates.

Communications gear is one of those deployment failures. While the Russians have advanced, jam-resistant, frequency-hopping software-defined radios (e.g., the R-187P Azart), most of their troops have been stuck using unencrypted radio, civilian walkie talkies, personal cellphones, and co-opted Ukrainian cell towers to communicate. This has resulted in the high death rate of Russian generals and the ability of every interested nation to listen in on Russian activity. Further, the focus on individual communication devices rather than a coherent system means the Russians have an incompatible stew of radios.

Deficient access to equipment has plagued Russian throughout its invasion. The early invasion saw inadequate clothing, food, fuel, and medicine, resulting in Russian troops - who should've been the most winterized force in history - suffering frostbite, starvation, and fuel exhaustion.

Since the Russians have been dependent on captured Ukrainian cell towers and civilian communications equipment, it's reasonable they'd exploit Starlink, too.

OSIRIS-REx probe sucked up more asteroid crumbs than hoped

Re: On the waiting list for Spring cleaning

It's basically made of unobtanium.

Or measurementerrorium. The 2012 study by Benoit Carry not only produced a density of 75-ish grams per cubic centimeter for Polyhymnia, but also some extremely high values for other asteroids of similar size (e.g., 675 Ludmilla, which had a density of about 73 g/cc). Carry considered his results unreliable. While Polyhymnia has not passed other sizable asteroids for additional gravitational measurements, a 2019 reanalysis of Lydmilla's orbit showed its density was more likely about 4g/cc (in the range of 2-6g/cc).

FAA gives SpaceX a bunch of homework to do before Starship flies again

Re: Moon landing

THey have openings where al lthe exhaust gases escape, stuff will get sucked in which is exactly what happened when in that Starship failure not that long ago

Rather longer ago, the largest rocket engines used on the moon did so without damage from flying debris. The Apollo LM descent engines and descent module never experienced dust/debris damage, though they did sandblast nearby structures (e.g., Apollo 12's damage to Surveyor 3). Apollos 12 and 15 had very dusty landings, with the crew commenting it felt like they were making instrument flight rules descents rather than visual. Despite that: no dust/debris damage.

Apollo 15 did experience engine damage but not from blown dust/debris. Apollo 15's LM was the first to use an extended engine nozzle to deliver more payload to the lunar surface. The nozzle extension was crumpled (as it was designed to do) when it crunched into the uneven lunar surface.

Europe's Ariane 6 rocket rated 'ready to rumble' after passing hot fire test

Re: ESA suffers from the same disease as NASA

There's that weird idea that SpaceX is competing with NASA again. NASA doesn't build or operate rockets, it runs air and space research programs. SpaceX doesn't have a space exploration program, it builds rockets and launches customers' payloads.

SpaceX had a designed, tested, and validated solution for around $250M.

SpaceX's initial Falcon 9 development costs of $400 million included about $250 million from NASA. Later reusability refinements on the Falcon 9 and development of SpaceX's Dragon capsule depended heavily on NASA's multi-billion dollar commercial launch services contracts and commercial crew delivery contracts. SpaceX's DragonEye docking system for the capsules was tested on shuttle flights (themselves run by a private company, the United Space Alliance) to the International Space Station (which was largely built by western private sector entities, like Boeing).

SpaceX is again getting billions of dollars from NASA to develop the Starship. As of last count, two loads of funding under NASA's Human Launch Services contracts have given SpaceX $4.04 billion to get Starship airborne and, eventually, deliver people to the moon.

SpaceX, like Boeing, Lockheed-Martin, Arianespace, and many other private entities, are contractors for NASA. NASA gets huge sums of funding from Congress to study space and then finds contractors to build and fly its rockets because the US public thinks it is uncool for government agencies to run, say, rocket factories. NASA's launch service contractors, meanwhile...

Companies like SpaceX are going to leave them in the dust, as they should.

...never created or ran space exploration programs. SpaceX hasn't put a penny of its own money into developing a deep space probe, running teams of space researchers and astronomers, or operating aerodynamics research labs like NASA has. SpaceX is a delivery service that builds its own delivery vehicles, with a developing side hustle in communications.

SpaceX has been groundbreaking in its advancement of launch services and cost reductions, which have pretty much knocked Boeing and Lockheed-Martin (operating as the United Launch Alliance) out of the market. Under Gwynne Shotwell, SpaceX has done some great work. And NASA is loving that SpaceX work: SpaceX lets NASA run redundant, competing lines of rocket and lander development to make sure Artemis gets to the moon whether the SLS tanks or Starship keeps blowing up.

It's just a misunderstanding to think that SpaceX is competing with NASA. They're doing completely different things.

SpaceX celebrates Starship launch as a success – even with the explosion

Re: Self destruct

Boeing isn't a private company; it's a publicly-traded company (ticket "BA").

I meant that Boeing isn't a public sector entity like the US government. Boeing is a private sector, for-profit corporation like SpaceX and, yes, Boeing is a public corporation while SpaceX is private. However, news articles aren't gushing about SpaceX being a non-publicly traded corporation achieving spaceflight, they're gushing about it being a private sector entity achieving spaceflight.

I found the point weird since because Western space-capable rockets have been built by the private sector since Mittelwerk GmbH's MW 18014 reached space in 20 June 1944. SpaceX is doing much the same as every aerospace company before it: it's a private entity taking lots of government money to go to space.

Re: Self destruct

He's doing what NASA would never be allowed to do, rapidly progressing launch technology through testing prototypes

The Starship is being developed on $4.04 billion in NASA funding so, in fact, NASA is rapidly progressing launch technology through testing prototypes.

More generally, NASA rarely builds rockets. Ever since Alan Shepard popped above the atmosphere on a Chrysler-built Redstone rocket in a McDonnell-built Mercury capsule, NASA has relied on private contractors for construction and operation. NASA didn't build the Saturn V. NASA didn't build the shuttle. NASA didn't build the Atlas V. NASA didn't build the Falcon 9. But it definitely funded them to varying degrees, and then hired their launch services for publicly-funded missions.

Further, it's a mistake to think that a contractor like SpaceX (or Boeing, or Lockheed-Martin, or ArianeSpace) is a rival to NASA when they're doing different things. NASA doesn't build and launch rockets. Instead, NASA runs space exploration and aerospace development programs assigned to it by Congress. SpaceX doesn't have a space exploration program, planetary research centers, or researchers seeking to explore space. Instead, SpaceX is an aerospace company that builds rockets and uses them to launch payloads from paying customers like NASA.

Re: I can't help but feel....

...that investors will only put up with so much

One of those investors is the US government, which has contributed about $4.04 billion to SpaceX for Starship development via the HLS contracts. NASA has a different tolerance for risk and failure than profit-seeking investors.

SpaceX's history is an interesting study in the US government's tolerance for risk. The first three Falcon 1 flights had the following customers:

Flight 1: US government's Defense Advanced Research Projects Agency (DARPA)

Flight 2: DARPA

Flight 3: NASA, ORS (a US government multi-agency effort), and the commercial entity Celestis

While those three Falcon 1's were exploding over Omelek Island, NASA was funding SpaceX with hundreds of millions of dollars to get the Falcon 9 airborne. As SpaceX's President Shotwell noted, NASA's funding was vital to getting the Falcon 9 off the ground.

Now, 17 years after Falcon 1 first flight blew up and after 17 years of listening to SpaceX brag about its "learning by exploding" process, NASA is throwing billions at SpaceX for a working, lunar landing version of the Starship. Because Congress is feeling generous about space funding, NASA is addressing its assigned task of "get to the moon" with a risk reduction approach for its mission rather than profits: it is funding SLS, Starship, and Blue Origin. If one fails then NASA has alternatives in the development pipeline. Further, NASA knows that SpaceX is going to take a more explode-y approach to spacecraft development than other private competitors like Boeing and Blue Origin.

NASA, metaphorically like SpaceX, is having a blast.

before insurers stop carrying the risks

The insurance carried for the Starship test flights is liability insurance in case rocket confetti lands on someone or their belongings:

"...part of the FAA licensing process is a calculation of the “maximum probable loss” from third party liability—that is, liability for harm to anyone other than the launch provider and the owners of payloads carried by the launch. The launch provider is then required, by the terms of its license, to carry insurance for the maximum probable loss amount, up to a cap of $500 million."

Since the insurance isn't for the rocket, which is expected to explode, and because no one's been killed by Starship yet, the insurers haven't gotten annoyed with SpaceX.

Falcon Heavy sends NASA probe to metal-rich asteroid Psyche

Re: I have to admit

All these billionnaires have really shaken up the landscape when it comes to accessing orbit.

Billionaires did, they got the ball rolling again while older private aerospace companies like Boeing and Northrop-Grumman dawdled.

Yes, it was inevitable as soon as the US government lost interest in space when the race was won.

And, fortunately, some of those billionaires had Presidents and COOs like Gwynne Shotwell, who figured out how to get reliable, stable funding for the billionaires' space dreams: the US government. The Falcon 1 flew with US government payloads when no one else would launch a satellite on it. The Falcon 9's development was funded by US government contracts like the Commercial Resupply program - without those hundreds of millions the Falcon 9 wouldn't have flown. The Dragon capsules, funded on US government programs, tested and refined their Dragoneye docking system on the last US shuttle flights. Now Starship is ironing out its development problems on billions of dollars from US government contracts.

The US government is willing to fund multiple routes to the moon (SLS and Starship) just like it funded multiple competing companies to resupply the ISS, which means NASA has been having a blast this past decade. NASA isn't stuck with the old, overpriced ULA launchers for its space probes, freeing money and making Congressional negotiations easier. It gets to issue and manage more contracts for more private companies, meaning more money to skim for itself. And if one of its private contractors collapses because its billionaire CEO has a meltdown or because its airliners stopped selling then NASA has well-funded alternatives already underway.

MOXIE microwaved Mars air into oxygen, but now it's time for a breather

Re: What happens to lots of carbon monoxide

The main thing that happens to Mars' atmosphere is it gets blown away by the solar wind.

On time scales of 100 million to 4 billion years, yes. Mars has an additional issue with low escape velocity, which also makes it vulnerable to Jean's escape mechanism and impact-driven atmosphere ejection. A reasonable asteroid that is a non-issue to Earth's atmosphere (if of more concern to dinosaurs) can drive eject nearby Martian atmosphere at more than escape velocity.

The Earth's magnetic field protects our atmosphere.

It may help. However, Earth has a couple of other advantages: a much higher escape velocity and much larger reservoirs of volatiles than Mars.

a huge (but not planet sized) magnet at Mars-Sun L1 would to the trick.

A LaGrange magnetic shield would help protect Mars on giga-year time frames. It wouldn't make much difference to most terraforming schemes or reasonable periods of human occupation.

Scientists trace tiny moonquakes to Apollo 17 lander – left over from 1972

Did Lockheed-Martin also want to be paid for their work in goats?

Lockheed-Martin has figured out the utility of more fungible currencies than farm animals, but (as of today) is still using US customary units for many of its products like the F-35. So does Boeing.

Except when they don't. You can find a lot of scientific work, like optics, being handled in SI units and then applied to hardware measured in US customary units. Even US suppliers may work in metric - UTC Aerospace (nee Goodrich) delivers landing gear to Boeing that was developed in metric.

Scientists spot startlingly close black holes in Hyades star cluster

Re: "we'd probably already be dead"

The only question is, at what distance are we doomed by a passing star or black hole ? If it is two light-years away, are we safe ?

While Matthew McConaughey or Beowulf Schaeffer might experience extremes of gravity skimming the black hole, a black hole doesn't have a gravitational field of larger dimensions than a star of the same mass because gravitational force is a result of the distance between two objects and their masses. Same mass, same distance, same force. For example, instantly swapping Sol with a 1-solar mass black hole would leave all of the solar system's planets and lesser objects in unchanged orbits.

The most likely black hole to pass by is a stellar mass black hole, which would be 5 to 30 solar masses (give or take a few kilograms). Taking the worst case of 30 solar masses at 128,000 astronomical units (2 light-years with some rounding)...

1. The black hole has 443 times as much gravitational force on Earth as Pluto at 40AU

2. The black hole has 70 times as much gravitational force on Earth as Alpha Centauri A+B at 275,000AU

3. The black hole has 1/30th the gravitational force on Earth as Neptune at 30AU

4. The black hole has 1/650th the gravitational force on Earth as Mars at 0.5AU

5. The black hole has 1/14,806th the gravitational force on Earth as Venus at 0.3AU

6. The black hole has 1/20,850th the gravitational force on Earth as Jupiter at 5AU

7. The black hole has 1/1,720,000th the gravitational force on Earth as Luna at 0.0026AU

8. The black hole has 1/540,000,000th the gravitational force on Earth as Sol at 1AU

Another way to look at this is: a star 30 times as massive as the sun would need to get within about 5.2AU (Jupiter's orbit) to match Sol's gravitational force on Earth. It'd be a pain at some thousands of AU, too, probably bothering the Kuiper Belt.

So, while Jupiter and Venus warp Earth's orbit a bit over a 405,000-year period, a singular passage by a large black hole at interstellar distances won't do squat to Earth or the solar system. If the Oort cloud actually is out there then it might be disturbed and we'd need to deal with a flood of comets in a few million years, but close passages by stellar-mass objects have happened before. Scholz's Star buzzed Earth 70,000 years ago at a distance of 52,000 astronomical units.

There is a matter of radiation from the black hole's accretion disk, but that shouldn't bother Earth much unless the polar jets swept over us.

BepiColombo probe turns to the dark side … of Mercury

Re: So

Why did they put the camera in a position with an impeded view?

Yep, Monitoring Camera 3's view of the BepiColombo spacecraft is crowded by that photo-bombing planet, ain't it? ;)

BepiColombo has three spacecraft monitoring cameras meant to look for problems like failed antenna or solar panel deployments. While they're not the high-performance spectrometers and imagers of BepiColombo's SIMBIO-SYS package, the engineering cameras can generate some cool PR visuals.

Caltech claims to have beamed energy to Earth from satellite

Re: Misdirection

Large space-based, microwave power transmitters are generally designed for safe power densities, like 1 milliwatt per square centimeter. Further, the beams were designed lose focus if the beam strayed from the rectenna though the reference to that is eluding me.

Astronomers spot Earth-sized exoplanet probably 'carpeted' by volcanoes

Re: Any architects care to comment?

New houses on LP 791-18d...

I'd go with a pontoon house boat. Stainless steel pontoons should be able to handle the heat of the lava. You'd need a good amount of insulation under the deck and an impressive air conditioner. Also, you might end up on water so the pontoon system would give you flexibility.

Perseverance rover shows up Curiosity with discovery of Martian water park

Re: Mars, what, where?

So we know quite well how to fsck Earth, let's find another target. In the meantime, let's spend an amazing amount of money on JSWT, Hubble and all types of muck leading to little else than pretty pictures feeding astronomers and astrologists alike...

The US is, hands down, the largest spender on space programs either in terms of totals or as a proportion of GDP. Currently, NASA's exploration efforts amount to about 0.3% of the federal budget, dwarfed by federal programs for the elderly, hungry, sick, and homeless. Saying "let's spend an amazing amount of money" on space when only tiny sums go to space programs therefore indicates one hasn't actually looked at government budgets or, worse, is being disingenuous.

Mars Helicopter completes 50th flight, 45 more than NASA planned

Re: COTS

Also, we may see smaller organizations, both private and public (such as amateur and universities) flying interplanetary missions.

Private organizations fly space exploration missions now. NASA and the ESA offer contracts with decent profit margins to their private contractors and university partners. Ingenuity, for example, was dependent on the design work of AeroVironment.

On their own, private organizations aren't going to do a lot of space exploration because there's no return on investment. SpaceX, often misconstrued as NASA's rival, has never built or operated a space exploration mission at all. Its in-house programs like Dragon, Starship, and Starlink are oriented toward the usual sources of money in space: communications, launch services, and government contracts.

If you're curious, NASA has some studies on the fun of getting COTS electronics into space systems:

COTS space hardware

You don't save as much money with COTS as hoped, there are reliability challenges, and testing over the full range of operating conditions inhales cash.

Launching soon: ESA's Juice to probe Jupiter's moons for signs of possible life

Re: A thought experiment for the class

I'm just wondering if for future missions To/Near Jupiter we can develop a power system that relies on that massive Jovian Magnetic Field?

Yes, they can, but you have to pay for that electrical energy from somewhere.

Electromagnetic Tethers can offer propulsion or power generation depending on current direction and the external magnetic field.

With electrical current flowing one way, perhaps from an RTG or solar panels, you can use an external magnetic field for propulsion and orbital reboost. Hubble uses a smaller, simpler Magnetotorquer system to aim itself and bleed down reaction wheels without rocket thrusters.

In the other direction, you can convert a spacecraft's velocity and kinetic energy into electrical energy. Basically, you trade speed for juice. This can be useful if, say, you wanted to de-orbit an old satellite with a lightweight system (some electrical wire and aging solar panels), slightly slow a space probe without aerobraking or rocket fuel, and so on. But you are trading away kinetic energy to get that electricity.

David Brin's 'Tank Farm Dynamo' is a short, 1983 hard science story looking at the utility of excess solar power and some long cables in orbit.

SpaceX calendar marked with big red circle for 'first Starship launch' this month

Re: New Reg unit required

16.5 million pounds of thrust - where's the metric for the rest of the world?

El Reg's unit converter says that's 22,812 Norrises. My TI-85 says it's 73.4 million Newtons.

Re: Stay up late

Anybody been recently?

I'm close enough that traffic makes it too troublesome to drive to Cocoa. Instead, I step into my back yard to watch.

It is very cool to see launches this frequently. We were supposed to have frequent shuttle launches by the late 1980s but Challenger ended that pace. It's been almost 40 years of waiting to see it get this fast.

I wonder if it is as busy these days with the routine launches?

I've got some friends in the Cocoa Beach-Titusville area who say that it's getting less crowded for regular launches. Something novel like an SLS or crewed launch gets major crowds. Cocoa was manic for the 2022 SLS launch.

Reg fashion: Here's what the well-dressed astronaut will wear on the Moon in 2025

Re: Looks aren't everything

Mobility and comfort of spacesuits have definitely improved since the Apollo A7L.

On the other hand, SpaceX doesn't have space suits. SpaceX has only produced pressure suits for emergencies, like depressurization during launch, and they're not intended for spacewalks or moonwalks.

The cause of last December's failed satellite launch? Nozzle material, says ESA

Re: Failing to compete?

ESA is not competing with SpaceX just like NASA isn't competing with SpaceX.

NASA and ESA do not build rockets. They hire private companies like Boeing, Lockheed-Martin, Arianespace, and SpaceX to build rockets and, often, space probes. Their job is to run space exploration missions as funded by associated governments, usually without a concern for profit.

SpaceX is a delivery company (with a side hustle in communications) that builds its own delivery vehicles. It doesn't build, design, or operate space exploration missions. It doesn't have the labs, networks of astronomers, and university researchers to conduct basic space exploration.

'Brittle' Twitter suffers bad case of the Mondays: Links, pics, vids fail

Re: Space X model

Seems that old Elon is treating Twitter like space X, test until failure then fix what needs to be fixed.

There's a bit of a difference between what Elon did at SpaceX and Twitter:

1. At SpaceX, Elon hired skilled engineers to build rockets. Then he got lots of DARPA, NASA, and investor money to design and test rockets. Then, yes, they tested rockets that exploded and learned from the test failures.

2. At Twitter, Elon is firing every engineer and manager who knows how the system runs while cutting expenditures that might be used for system improvements. The resulting failures aren't from deliberate testing but rather lack of maintenance and dwindling system knowledge. Even if the failures were from deliberate tests then Elon has laid off the skilled personnel who know how to use the resulting test data.

NASA finds crashing spacecraft into asteroids is a viable defence strategy

Re: Worrying.

Perhaps they don't know the the mass of the asteroid? But 4x!?

That was addressed in El Reg's article. Besides the momentum transfer of DART's impactor, the plume of debris ejected by the impact had a stronger rocket-like effect than expected. It's hard to model the behavior of a milli-G pile of dust and gravel during a deep impact.