Posts by cray74

Apple hands €14.3bn in back taxes to reluctant Ireland

Dear Sir,

I have been requested by the Irish Corporate Tax Escrow Fund to contact you for assistance in resolving a matter. The Irish Corporate Tax Escrow Fund has recently collected a large sum of taxes from the Apple Corporation. The taxes have immediately produced moneys equaling € 14,300,000,000. The Irish Corporate Tax Escrow Fund is desirous of releasing this money to taxpayers, however, because of certain regulations of the Irish Government, it is unable to move these funds.

You assistance is requested as a non-Irish citizen to assist the Irish Corporate Tax Escrow Fund, and also the Central Bank of Ireland, in releasing these funds to taxpayers. If the funds can be transferred to your name, in your United Kingdom account, then you can forward the funds as directed by the Irish Corporate Tax Escrow Fund. In exchange for your accommodating services, the Irish Corporate Tax Escrow Fund would agree to allow you to retain 1%, or € 143,000,000 of this amount.

However, to be a legitimate transferee of these moneys according to Irish law, you must presently be a depositor of at least €143 in a Irish bank which is regulated by the Central Bank of Ireland.

If it will be possible for you to assist us, we would be most grateful. We suggest that you meet with us in person in Dublin, and that during your visit I introduce you to the representatives of the Irish Corporate Tax Escrow Fund, as well as with certain officials of the Central Bank of Ireland.

Please call me at your earliest convenience at 1890 201 1060. Time is of the essence in this matter; very quickly the Irish Government will realize that the Central Bank is maintaining this amount on deposit, and attempt to levy certain depository taxes on it.

Yours truly,

Prince Garret FitzGerald

New MeX-Files: The curious case of an evacuated US solar lab, the FBI – and bananas conspiracy theories

I always WONDERED why they used Mercury bearings

Maybe because the tiny group of engineers and specialists who build astronomical instruments are familiar with mercury, not the alternatives.

My division of an aerospace company loves metals, and it likes generous mid-range alloys like 6061 aluminum and precipitation hardened stainless steels (17-4, 15-5, etc.) When we recently needed a stronger, more fatigue-resistant aluminum alloy that led us to pick from the 7000 series, we had to learn partly by trial and error how to deal with its its forging, heat treating, and repair/rework behavior. It's been an expensive learning process figuring out an aerospace industry workhorse alloy because no one on the project has worked with it before.

If it hadn't been for a customer both willing to fund our learning curve and remain unyielding on over-the-top safety margins, we'd be back to 6061 in a heart beat.

So I can completely imagine some instrument maker faced with the tight budget of a grant-funded astronomy lab sticking to old, tried-and-true mercury solutions rather than trying to research and master replacement materials.

Russia: The hole in the ISS Soyuz lifeboat – was it the crew wot dunnit?

They used to use velcro ... until Apollo 1

They still use Velcro in space. The role of Velcro in ISS sandwich making

Pluto is more alive than Mars, huff physicists who are still not over dwarf planet's demotion

Re: Not University of Florida

University of Central Florida - much smarter boffins!

UCF's professors of astronomy might be smarter. My experience with the engineering interns of UCF and UF is that University of Florida students need less remedial training and hand holding to get started in the work place. UCF just seems to leave out little details in lab work, team work, and technical communications that UF addresses.

Neutron star crash in a galaxy far, far... far away spews 'faster than light' radio signal jets at Earth

Re: And that's why I don't bother with these comments sections any more.

So I have concerns about the research or about how it was reported.

It usually helps to provide a link if there's a factual error in the article. If your objection is to how the article's reported then it's more constructive to use the link in every Register article ("tips and corrections") that lets you inform the writer because they don't always check the comments section.

But, to give you a response on your concerns:

That collision, I thought, resulted in a bigger neutron star and not a black hole, according to the observation I seem to recall.

Current speculation is that a black hole resulted, though there are disputes because it'd be the lightest black hole yet found.

And even if it did somehow turn into a black hole after some time, how can that effect the gravity field of the new object at a distance?

I don't follow the question because the new object IS the black hole. The gravity field effects happened prior to the collision in that the two spiraling neutron stars shed orbital energy by radiating gravity waves. This loss of energy eventually caused the neutron stars to collide, spew gold everywhere, and collapse into a black hole or larger neutron star.

Afterwards, all the exciting effects are from conventional gamma ray and radio wave emissions from the resulting accretion disk, which is the topic of this article.

I believe at best these are separate events that just happened in the same area of the sky at similar times from our point of observation.

Three events that behaved as if they're related? Observations show neutron stars radiating gravity waves spotted by LIGO, followed the gamma ray burst consistent with neutron stars colliding, followed by radio emissions of an accretion disk from the debris cloud - that's rather consistent with a single event, not several related observations happening in the same space.

Roskosmos admits that Soyuz 'meteorite' hole had more earthly origins

Re: Makes me wonder

What would happen if a similar hole was drilled in the Bigelow module

The Bigelow modules, like Transhab before them, are 50cm of layered ceramic cloth, foam, and fiber-reinforced pressure films. The hole wouldn't grow because of the rip-stop nature of the armor and strength layers.

Repair would be interesting. You'd be filling a 50cm-long bore and trying to get an adhesive to stick to polymers that sometimes don't play well together. However, given the small diameter of the hole and low stress (a few pounds of air pressure at the most), a long plug of epoxy injected in there would probably stick and hold in place.

Did it occur on the ground or in space?

The picture seems to include some drill marks in the surrounding paint, which implies it happened after assembly of the Soyuz's orbital module.

The whole "drilled and filled with adhesive" sounds a lot like some of the repairs I've specified for bad castings** used in aerospace applications, so I could believe it happened on the ground. Then again, that sort of repair usually happens long before painting. If the repair is decided after painting, we strip the paint, patch the hole (Loctite ea9394 is awesome), sand down to tolerance, and repaint. You wouldn't have those drill skip marks around the hole.

**The stainless steel castings are expected to hold some pressure because the sensors and electronics behind them are air-cooled, but a) there are no lives depending on the pressure seal, and b) the strength margin is ludicrous, so some high strength epoxy in a casting porosity is safe. One of them came back to the factory missing one of its sapphire window panels, paint half blistered off, and packed with mud and fire retardant - it turned out to have been under the wing of a British Harrier that had a bad landing in Afghanistan. We were able to use the casting to train factory operators in window installation because it was still within its dimensional tolerances of +/- tiny.

Trainer regrets giving straight answer to staffer's odd question

Re: Still happens

it is AMAZING how butter-fingered the sales people become, and how many times their laptops "slip out of their hands whilst running on a pavement".

Instead of breaking unwanted hardware, have you ever encountered bribery for new equipment and did it work?

I've found that polling the IT department for favored cookies and sodas, and leaving unsecured packs of the preferred snacks at my desk helps the quality of hardware I receive during a refresh.

Space station springs a leak while astronauts are asleep (but don't panic)

Re: How did they find it?

Step 1: seal each compartment, monitor each compartment for pressure. This identifies the compartment the leak is in.

That was the basic technique . A 2mm hole wouldn't generate a draft that would stir dust or light objects.

I'm surprised El Reg didn't mention that prior to taping the puncture, an astronaut (Alexander Gerst) plugged it with his finger.

Drama as boffins claim to reach the Holy Grail of superconductivity

Re: Context, context, context

When I complained to my physicist friend about twenty five years ago, he responded, "liquid nitrogen is cheaper than milk."

Cheaper than milk, soda, and unleaded. In the 1990s, the lab I worked at was purchasing liquid nitrogen at about $0.06 per liter. It led to some interesting economic design decisions in experimental equipment. Electricity for sample heating was expensive, but nitrogen for cooling was cheap.

It's official: TLS 1.3 approved as standard while spies weep

Historical Revisionism or Mind Control Satellites?

The mass surveillance of internet communications by the US National Security Agency (NSA) revealed in 2013 by Edward Snowden,

In 2005-2007, major media groups like the New York Times, Reuters, BBC, and numerous others described the NSA's warrantless mass surveillance of the internet, phones, email, office gossip, and pillow talk. This incredible violation of privacy filled the evening TV news, internet websites, and newspapers.

After a few years of quiet, in 2013 Edward Snowden reminded the world that the NSA's surveillance was still happening.

However, most discussions I see today about the NSA's internet monitoring hail Snowden as the hero who FIRST told the world about it. It's like all the news coverage, ACLU lawsuits, and outrage of the late 2000s didn't happen and Snowden revealed something new. Maybe the NSA asked the CIA to use their mind control satellites to blank everyone's brains for a few years.

Non-rhetorical question: Is there some key difference between 2006 NSA internet surveillance and 2013 NSA internet surveillance that makes Snowden's revelation particularly novel? I feel like I'm missing something that makes Snowden different than all the earlier revelations.

Blast from the past: Boffins find the fastest exploding non-supernova star

Particularly if it produced a gamma ray burst and if this was angled towards earth

Which wouldn't be a problem for Earth. GRBs are only threatening if they fire within a few parsecs of Earth, at which distance they could cause serious ozone degradation, a bit of a 'GRB winter' and some acid rain.

Sorry, Neil Armstrong. Boffins say you may not have been first life-form to set foot on the Moon

Re: But NASA still haant found....

When you read it you'll notice that they spend around 11 hours (there + back) in the Van Allen distances of earth. With a 90 minute (IIRC) orbit that's impossible to miss the belts, so they'd be fried.

You recall incorrectly. The Apollo missions completely dodged the inner Van Allen belt and only passed through the fringes of the outer belt. During that time, the astronauts were restricted to the thick-skinned Apollo capsule. All that ablative heat shield - mostly carbon and hydrogen - does a great job of soaking up Van Allen electrons.

I'm sure you know Earth's magnetic field is substantially tilted compared to the moon's orbit. Between the tilt of the field and Luna's orbital inclination, there's almost a 30-degree difference between the two, which allows a low-orbiting Apollo stack to dodge the inner belt.

Diagram of the dodge around the belt

Re: " Getting a sufficiently thick atmosphere would require"

And you also need to keep it there.... which would require a magnetic field as well to shield it from Sun energetic particles. Which also are not nice to life forms

An Earth-like atmosphere offers radiation shielding similar to about 10 meters of water, which will stop any electrons, protons, or x-rays from the Sun. With sufficient oxygen, it will also screen UV radiation, too.

That does leave the problem of solar wind erosion of the atmosphere, but Mars should be able to hold an Earth-like atmosphere for about 100 million years. That moves the issue of atmospheric erosion firmly into the category of "let the grand kids deal with it." ;)

Terraforming is largely about taking what's already there and rearranging it so it can support life.

Then you're never going to terraform Mars. Its native nitrogen and water resources are very limited. Getting a sufficiently thick atmosphere would require very large nitrogen and water imports, and I don't mean sci-fi's popular, "hit it with a few comets."

Native Martian water resources would cover the surface to a depth of about 6 meters. Concentrated in the likely lowlands - the North Polar Basin that covers 40% of Mars' surface - and you get an "ocean" of 15 meters depth. To fill the North Polar Basin to 1 kilometer depth (a useful ocean size for supporting a global water cycle), you'd need another 58 million cubic kilometers of water. That's a sphere of water about 480km in diameter, or more than the entire water content of Enceladus or Ceres.

Nitrogen is similarly in short supply. To get an Earth-like atmospheric composition for a world with 28% of Earth's surface area, you need to import about 28% of Earth's atmospheric mass of nitrogen. (That's ignoring the difference in scale heights due to lower gravity.) Since Earth probably doesn't want to share then you'd need to remove about 24% of Titan's atmospheric mass or 9% of Venus's nitrogen.

A one-stop source for Martian terraforming might be Titan. Get some von Neumann robots running wild and you can strip-mine its crust to about 1 kilometer depth for sufficient water, liquefy a quarter of its atmosphere for the nitrogen, and start flinging the goods to Mars by mass driver. If you're thinking of terraforming Venus, it has excess nitrogen (three times' Earth's inventory) and plenty of spare carbon that would be useful on Mars.

Re: "..one small step..."

You know NASA's official position on the telemetry tapes for all 6 missions is that they are "lost"?

NASA's official position is actually that they only lost Apollo 11's original video telemetry tapes. As NASA said, "First-generation copies of the converted video from Apollo 11 as well as other first-generation copies and some original versions of the converted video for the Apollo 12 through Apollo 17 flights are still in NASA Johnson Space Center's Informational Resources Directorate's video vault in Houston."

As Corning unveils its latest Gorilla Glass, we ask: What happened to sapphire mobe screens?

Re: Anyone remember this?

GT was greedy - they promised Apple they could make the silicon ingots

**alumina ingots ;)

GTAT's failure is interesting from both technical and legal standpoints. Frankly, it should be a case study for industrial engineers on how not to scale-up your process rapidly.

For me, GTAT's failure turned one of my suppliers into a nearly vertically-integrated monopoly of sapphire windows when they snapped up GTAT's liquidated remains, both personnel and hardware. It's been a scramble to find second sources for big sapphire panels (we use panes the size and thickness of iPads) and window assembly.

Re: Transparent Metal

We keep hearing about various types of transparent metal that will be used in everything from screens to buildings.

The recent references to any kind of transparent metal are to "transparent aluminum" when someone does something interesting with either aluminum oxide (alumina, sapphire) or aluminum oxynitride (AlON) and then a science-deficient media gets hold of the story.

Transparent metals of any significant thickness are a non-starter because photons interact with the electrons of the conductive material. You need band gaps - like those found in insulators - to pass any photons. Your possible transparencies are thus polymers, ceramics, and other non-conductive materials.

If you want transparency with a lot of ductility and impact resistance, your options narrow to polymers.

Wearable hybrids prove the bloated smartwatch is one of Silly Valley's biggest mistakes

and the shopping list is on a notepad hanging on the fridge

I only went to a list-making app (Note Everything) on my phone after years of repeatedly forgetting my handwritten grocery list. I almost never forget my phone but my grocery list stayed at home more often than not.

Crooks swipe plutonium, cesium from US govt nuke wranglers' car. And yes, it's still missing

Re: I work in the field

If you think this is scare mongering, then I regret being restrained, and not going balls out

In the opposite direction of scaremongering, some useful context might've been provided with a sentence to the effect of, "Typical plutonium check sources have X curies of radiation, which compares to a dangerous dose of Y curies."

Most news articles on radioactivity threats - like the recent radioactive sinkhole in Florida - neglect context like that and people get alarmed over something less radioactive than a banana.

What does it take for an OpenAI bot to best Dota 2 heroes? 128,000 CPU cores, 256 Nvidia GPUs

Re: How many orders of magnitude

This is about playing WW3

"A strange game. The only winning move is not to play. How about a nice game of chess?"

Unbreakable smart lock devastated to discover screwdrivers exist

Zamak 3

"Unfortunately, as materials engineers are happy to point out, aluminum may be a lovely lightweight metal..."

Zamak-3 is actually about 95% zinc and not more than 4.3% aluminum.

Astronaut took camera on spacewalk, but forgot SD memory card

Well, I suppose we're all thinking that an astronaut should be more than capable of understanding a 'no SD' message. On the other hand, a spacewalk is a very high-pressure environment

It's not just astronauts during EVAs. I'm an engineer working in an aerospace company. This morning three of us, collectively holding seven college degrees (none in IT), stood around a desk telephone trying to figure out why it wasn't working. We got as far as confirming it was plugged in before giving up and putting in an IT maintenance request.

Everybody has brain farts with technology, especially outside their specialties, but most of us are lucky enough not to be caught on a grand stage like this astronaut.

NASA’s new exoplanet-spotter survives sling past the Moon

Re: How far?

I've seen it reported as 5,000 miles in 'Murican coverage, so 8,000km makes sense.

8km - that's plenty of clearance... (most of the time)

Back in the days of yore (before the Mun had topography) I manually parked a spacecraft in a 1km orbit. Recently, for old times' sake, I tried again and started with a "safe" 5,000-meter orbit. That's when I found new versions of Kerbal Space Program had given the Mun mountains of up to 6,000 meters height, and that vigorous lithobraking maneuvers still produced lots of rocket confetti.

Bowel down: Laxative brownies brought to colleague's leaving bash

Re: BOFH Trainee?

No need to sabotage, just make them 'sugar free with Maltitol' since this is a laxative....

I did get some of those infamous sugar-free gummy bears for Christmas, which helped me avoid significant caloric gains from giant holiday meals. As I hadn't dented the inventory of the 5-pound bag and considered my curiosity satisfied (teh interweb rumors were true!), I was happy to turn the remainder over to my brother.

He's a fire fighter and the popular prank at the station was to put million-Scoville hot sauce on the rims of coffee mugs or toothbrushes. They weren't ready for a bowl of innocuous, tasty gummy bears.

Decades-old data reveals shows Jupiter’s moon sprayed alien juice over Galileo probe

Re: "Decades old data"

"I'll just get the Saturn Five plans..."

"Oh, wait..."

...You don't have a microfilm reader? ;) Contrary to John Lewis's claim in "Mining the Sky" that the blueprints are gone, NASA preserved the blueprints for the Saturn V at the Marshall Space Center in microfiche format. Documents for ground support equipment are also preserved.

NASA demos little nuclear power plant to help find little green men

Re: Only 10kw?

Except for manned spacecraft, not many spacecraft have used 10kW. In fact, all of the deep space probes like the Voyagers utilized a few hundred watts.

It's not rocket science! Actually it is, and it's been a busy frickin week

How do they achieve an accurate orbital insertion with no throttling ability at all?

Selective steering to waste energy? You don't have to follow an optimal, energy-minimizing flight path to orbit if you have excess solid fuel to burn. You can take flight paths with unnecessarily high or low inclinations, or even use "energy management maneuvers" like Lockheed-Martin's THAAD.

And the final satellite, if not an upper orbit insertion stage, will be able to throttle and maneuver to a desired orbit.

Want to make a super-earth? Bring on the frikking lasers

Are the crystal structures achieved in tiny fractions of a second necessarily representative of what you'd find in the core of a planet? Crystal structures often change over time as they settle into their favored, minimal energy form. Look at 7000-series aluminum alloys and how they can alter their properties at room temperature unless you overage them.

India completes its GPS alternative, for the second time

Re: now how about spending the same billions...

Look at USA spending on Military vs Education and Healthcare, both of which are very poor for the average US citizen compared to OECD / GDP per head.

You're not looking at that US discretionary spending pie chart that's going around, are you? The one that shows US military spending as 54% of the federal budget? The USA's defense & security spending is about 18% of its total federal budget, while two of its welfare departments - Health & Human Services, and Social Security - are individually larger than the Department of Defense. I mean, that's a huge amount of military spending, but it's not dwarfing or draining other departments' budgets.

Regarding US educational spending, including state and local budgets, that's larger than the OECD average both as a percentage of its GDP (7.3% vs 6.3% OECD average) and per capita ($15,171 vs $9,313 OECD average). Not that the results are better, but the US spends more on its students than the OECD average.

Overall welfare / social services spending by the US is below the OECD average, but it's 19.3% isn't vastly lower than the 21% average.

How life started on Earth: Sulfur dioxide builds up, volcanoes blow, job done – boffins

Re: Earth has 800,000 cubic miles of Uranium with 4.4 billion year half life....

Jurassic pterodactyl wingspans indicate four times air density 60 million years ago.

1) Jurassic pterodactyl wingspans work fine in current air density, too

2) Fossil rain drop craters indicate Earth's air density has been constant for billions of years

Doomed Chinese space lab Tiangong-1 crashes into watery Pacific grave

Re: More trash for the ocean

I know, I took a spent uranium fuel rod to the local tip, but they said they don't handle that sort of thing. It's ridiculous, I wrote to my local MP about it.

Ridiculous is the look on management's faces when you tell them that FedEx lost your radioactive waste shipment on the way to the disposal site. But that's getting a bit off topic from Tiangong 1's final disposal.

Re: Control? No Control?

Note: Always remember that these posts are moderated, this is not an open discussion of the issue.

If the moderators' IP address isn't behind the Great Firewall of China, then you don't have to worry about moderation hindering presentation of the pertinent points about this discussion. Such as:

1) Tiangong 1 came down significantly closer to American Samoa than Point Nemo. This is not consistent with the behavior of a controlled disposal at Point Nemo.

2) The CNSA and China in general would be crowing about the safe disposal of Tiangong 1, which would grant them some technical and diplomatic brownie points.

3) Amateur satellite watchers would have noted the controlled attitude and radio transmissions from Tiangong 1, instead of its silence and drifting attitude. The loss of control of the station was first confirmed by amateur astronomers in 2016, not China, who was only muttering about loss of telemetry.

As far as conspiracy theories go, "China had secret control over Tiangong 1 and used it to do nothing, not even transmit basic telemetry, for 2 years until guiding the station into missing a satellite graveyard by 2000 miles," needs a little polish.

Uber self-driving car death riddle: Was LIDAR blind spot to blame?

Re: "...a [Lidar] blind spot low to the ground all around the car."

Even a carbon framed bike carries a large amount of metal.

Lidar <> radio frequency radar, so the metal or carbon fiber content are unlikely to be relevant. The question is: did the bike and pedestrian reflect laser light?

Veteran NASA probe Dawn: Winter is coming on Ceres (sort of)

Or carry a spare wheel? In the trunk?

That's common actually. Three wheels are needed for all-axis control, but four are typically included in the design.

Negative Reactions

Kepler, Dawn, Hubble, Hayabusa, ROSAT, and others have been hampered or outright ended by reaction wheel failures. What are the common failure sources of the reaction wheels, frictional/wear related?

Kepler krunch koming: Super space 'scope's fuel tank almost empty

So, the scope can continue to function indefinitely, it just can't manoeuvre. Maybe the question should be, what is the most interesting part of space to point at before the thrusters die?

The disappointing follow-up question being, "And how would you hold that aim point without fuel and reaction wheels?"

Unfortunately, Kepler is already on a reduced-function mission, the K2 or Second Light mission. The K2 mission came about because of the failure of 2 of 4 reaction wheels on Kepler (in 2012 and 2013, respectively). K2 depends on some clever solar sailing, at least in the sense of preventing light pressure from disturbing Kepler's aim while it makes months-long "viewing campaigns" of certain areas of the sky.

Under the K2 mission, Kepler's view changes through the year due to its rotational inertia, light pressure, and need to avoid letting sunlight directly down its telescopic throat. This period of reduced function still depends on the reaction wheels and fuel as Kepler must be periodically rotated. (See link above for a diagram.) Lose another wheel or run out of gas and you lose aiming control, at least partly due to the inability to fight sunlight pressure.

So, when you aim Kepler into the Great Beyond for its hypothetical fuel-free K3 mission, it's not going to hold that aim for long. Not even months.

Russian boffins blow up teeny asteroids with tiny laser... to work out how to nuke the real thing

Re: I'm curious...

What's the difference in total kinetic energy delivery between a solid mountain hitting us at orbital speeds, and a mountain full of pebbles hitting us at orbital speeds?

The difference between Barringer Crater and the Chelyabinsk meteor, give or take a few megatons.

The pebbles might not survive to ground level, but they're still going to be dumping all that energy into the atmosphere; there isn't any less of it because the mountain's been blown up.

Yes, but air bursts have the advantage of being kilometers to tens of kilometers overhead. Above a certain amount of energy (see: May 19th, 66,000,000 BC) that's irrelevant, but for more common asteroid threats it makes a significant difference. Pebbles are exactly the sort of space debris that burns up at 50-80km altitude, a distance that is preferable to 0km. ;)

Seeing it sooner and moving it out of the way seems a more logical course of action.

Agreed. A nuclear-delivered course correction is one way to achieve that. If you can deliver enough energy to fragment several hundred meters of rock, then you can deliver enough energy to ablate some millimeters of surface and start that course correction. Given a year or two, it'll add up.

Are you Falcon sure, Elon? Musk vows Big Rocket will go up 2019

Re: Musk really does see himself as the Saviour of Mankind

Now if you want to mine Helium-3, then that's a very fine reason to establish a mining outpost

Only if your space mine is cheaper than breeding helium-3 on Earth. Helium-3 is a decay product of tritium, which has been produced industrially on Earth by neutron spallation of light elements like lithium. Beryllium and boron are also suitable spallation targets if you want to save lithium for batteries.

Re: Musk really does see himself as the Saviour of Mankind

There's very little on the Moon to exploit for resources, and nothing at all at L5.

The moon has all the resources of Mars except hydrogen, nitrogen, and carbon, and hydrogen has been arguably detected there. If not, it's certainly nearby on Earth.

.

That was the premise of NASA's 1994 LUNOX study: use the resources of the moon to support Earth orbit and cis-lunar operations, including importing hydrogen from Earth. Once you're extracting oxygen from the moon, you're getting at least 83% of the propellant mass needed for rocketry from a smaller gravity well than Earth. By switching to higher oxygen ratios than current rockets, like 7:1, you could source 87.5% of propellant mass to the moon.

.

And by switching to sulfur-oxygen "Brimstone" rockets, you could get all your propellants from the moon since Luna has plenty of both sulfur and oxygen. Brimstone rockets are not high performance (~2500m/s exhaust velocity), but they avoid the erosive solid combustion products of metal-oxygen rockets; both propellants are manageable as liquids; and 2500m/s is sufficient performance for lunar and near-Earth operations.

.

On the other hand, Mars' advantages in confirmed hydrogen, nitrogen, and carbon resources are at the end of a long transit time. While helpful for Martian colonists, it makes Mars less attractive as a supplier of near-Earth propellant needs.

Re: Closing down sale?

what are they going to call the next one and the one after that, as they get bigger and bigger?

Tiny, because it doesn't feel the need to compensate with its name? ;)

Re: Musk really does see himself as the Saviour of Mankind

The logical way forwards seems to be to build a base/assembly point at one of the Lagrange points (L4 or L5 are the obvious choices) followed by a moon base (nice and easy to leave as well...)

I'd start with the moon base for the resources, since there's not much at L4 and L5 except microgravity and solar power otherwise. But otherwise I would focus on cislunar space and the moon over Mars. There's not a lot of advantage to Mars over Luna except for guaranteed hydrogen supplies, and you're stuck at the end of a months-long logistical corridor when you settle on Mars. If something on Mars needs a replacement part from Earth, that's 3-9 months away. If someone needs terrestrial medical services on Mars, that's 3-9 months away. If you need replacement personnel, that's 3-9 months away. If you need to re-engineer a system, the replacement is 3-9 months away.

The moon's advantage is that 3-day transit time, or 24 hours if you've got some spare delta-V like NASA's 1994 LUNOX study suggested. 1 to 3 days is on the time scale of resolving problems at a manufacturing company's supplier or remote site on Earth, and it's tolerable for medical emergencies (moreso than 3-9 months). The moon has all sorts of materials (metals, oxygen, sulfur, or regolith) that can be delivered to cis-lunar customers for fuel, reaction mass, shielding, and other applications, where 1-3 days is again preferable to 3-9 months.

I mean, I'd take either the moon or Mars, whichever eventually gets funded. I'm not the one with the BFR. Or billions of dollars. The moon just eliminates the hurdle of months-long spaceflights.

and since nobody has any weaponry that will exit orbit then a moon base would be perfectly safe in WW3,

And the delta-V to reach a moon base isn't much lower than the delta-V to reach a Mars base. If you do have weaponry that can reach the moon, it could (eventually) reach Mars.

I didnt think it had flown more than once, but apparently it took both the Buran and Poylus into orbit.

I was going to correct the Polyus part but, no, Energia did its job of putting Polyus into an elliptical orbit. This wouldn't have lasted long since the perigee was in the atmosphere, but it was a course with orbital velocity achieved and a pretty standard flight path - the shuttle also initially entered such an elliptical orbit and then performed one or two injection burns.

After Energia was done with its part, Polyus's attempted circularization burn was actually a de-orbit burn. Polyus was launched upside down in its cargo fairing for structural (?) reasons and had to rotate 180 degrees before firing its engine. The IT angle for El Reg readers is that a software goof resulted in Polyus rotating 360 degrees and firing its engine in exactly the wrong direction.

But how does it compare to the Energia rocket?

The two flown Energia rockets had 6.5 million pounds of thrust at takeoff, with a capability of putting 100 tons into low Earth orbit. The Saturn V had 7.8 million pounds of thrust at takeoff, with a capability of putting 130 tons into LEO.

So, as the BFR is about twice a Saturn V, it's about 2.6x an Energia. Approximately, give or take a bit.

There were some planned Energia configurations with higher takeoff masses and thrust levels, but those didn't get off the drawing board.

Violent, powerful wind that lasts 100s of years. Yes, it's Jupiter, not you after a Friday night curry

Re: the huge pressures involved

I thought most hot Jupiters migrate to the inner star system from further out?

Modern variations of the "Nice Model" include "Jumping Jupiter," which posits the solar system started in a denser configuration but after about 500 million years (the time of the Late Heavy Bombardment), movement of Neptune and Uranus (and potentially a 5th gas giant) adjusted Jupiter's and Saturn's orbits. Hilarity ensued as Jupiter and Saturn entered a resonance and drove the gas giants outwards. Debris in a much-denser proto-Kuiper Belt is the source of momentum to adjust planetary orbits.

Basic Nice Model

Farts away! Plane makes unscheduled stop after man won't stop guffing

Re: Clear the area

Nah, this trumps it.

I seem to recall contributing a review to that bag of Gummi bears, though I can't pinpoint it in that vast list.

Can't wait to get to Mars on a SpaceX ship? It's a cold, dead rock – boffins

Re: Not a huge priority

And the colonists don't have to stay there, and don't have to die.

Colonizing Earth's oceans makes you immortal?

Anti-missile missile misses again, US military mum on meaning of mess

Re: Marco

Was that included in the 16?

No, I think my numbers were for controlled tests only and excluded the USA-193 shoot down.

Re: Marco

Concur. It is pretty clear that in this area USA is about a decade behind Israel

What are the success rates of Israeli anti-missile tests, and how do the test targets differ from US testing?

The US had some rough starts with THAAD in the 1990s (4 of 11 tests were successes), but in the 2000s-2010s it was successful in 13 of 17 tests (and the other 4 were aborts or cancelled, not operational failures.) The latest test gave the THAAD crew no schedule for the target launch and, as far as I've read, the target wasn't helping THAAD with telemetry.

The SM-3 has also hit 16 of 19 targets in the 2002-2010 period, and 26 successful tests by 2013. While some of the tests are simplified, others successfully engaged targets with separating warheads, and the Russians were grumping in 2016 that the SM-3 could intercept IRBMs (admittedly: not ICBMs) before warhead separation.