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Last year Lego picked, as one of its fan-suggested kits, the Apollo Saturn V moon rocket. About a month ago details of the final kit emerged, with a launch (ahem) date of 1st June. Then on Friday a friend mentioned over on Facebook that John Lewis had the kit in stock early. I checked and there it was, with the option of next-day pickup in our local branch. The decision to order took, I don't know, about 5 milliseconds, and on Saturday afternoon we popped in to pick up what proved to be an impressively large box.

Lots of pictures of Lego building )
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Tim Peake isn't the first British astronaut, is he?

No. By any practical definition that would be Helen Sharman, who flew on the Juno mission to Mir in 1991.

So why is he being described as the first 'official' British astronaut?

Because his flight is formally supported and (via the UK's contribution to the ESA human spaceflight programme - which the UK only recently started funding) paid for by HM Government. This is the first time that has happened.

So Peake is the first astronaut sponsored by the UK?

No, that would be the Skynet 4 Payload Specialist group selected in 1984, all of whom were UK government employees (three military, one civil service) for two missions paid for by the UK. They never flew, because after the Challenger disaster the Skynet 4 satellites were rebooked onto expendable launchers, but they were definitely official British astronauts.

OK, so he's the first official British astronaut to be allocated to a space mission?

No, that would be Squadron Leader Nigel Wood (assigned to shuttle mission STS-61H) as part of the Skynet 4 programme. As noted above, the mission was cancelled post-Challenger, but Wood got to within 6 months of flight.

But even if they never flew the Skynet 4 group were the first British astronauts?

If you mean 'born in the UK' then no, that honour goes to Anthony Llewellyn, born in Cardiff in 1933. He became a naturalised US citizen, was selected as part of NASA's second scientist-astronaut group in 1967, but resigned before being assigned a mission.

Sharman wasn't an 'official' astronaut then?

Yes and no. The Juno mission was privately-funded, or was meant to be, but the basis of the mission had been agreed at a fairly high level (seemingly between Thatcher and Gorbachev). What seems to have happened is that the UK Government was initially happy to support Juno in every respect except paying for it, but when it became clear that there was a lot less appetite for private sponsorship than had been assumed the Government rather distanced itself from the project and the Soviet Union ended up paying the bill. Since then Sharman's flight has been rather conflated with later 'tourist' missions (such as that by British-born Richard Garriot) but in truth it had a fair bit of official support.
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I've been interested in space and astronomy all my life, and I'm a lawyer. As such I've been thinking about the question - back in the public eye again with the Pluto encounter - of what the rules should be for defining a planet.

Here is my suggestion on the 'what is a planet' question in light of what we saw at Pluto.

A planet is a celestial body that:

1) Orbits the sun, not any other body.

2) Has achieved hydrostatic equilibrium (i.e. its own gravity has squashed it to be round).

3) Has one of the following properties:

3a) Is a gas giant*; or

3b) Has a surface modified by self-generated geological processes.

(*A more formal definition might be along the lines of 'more than half its mass is not in solid phase')

Point (1) excludes geologically active moons such as Io, Triton or Enceladus.

Point (2) excludes comets.

Point (3a) is probably obvious but ensures that Jupiter etc count despite not having a 'surface' for the purposes of point (3b).

Point (3b) is what distinguishes a planet from a large asteroid and also excludes Io etc as their geological activity is generated externally (tidal forces from their primary body).

On this definition, Jupiter, Saturn, Uranus and Nepture are all planets by virtue of point (3a). Mercury, Venus, Earth, Mars and Pluto (as seen in the last couple of days) are all planets by virtue of point (3b).

Pluto and Charon probably count as a 'double planet' given that Charon seems to meet (3b) too.

Ceres is not a planet because it doesn't meet (3b). Vesta is not a planet because it doesn't meet (2) or (3b).

Until we see their surfaces, we cannot class Eris, Haumea or Makemake as planets because we do not know that they meet (3b).

This definition returns us to the nine-planet solar system. It allows for Kuiper belt objects to be defined as planets if it turns out that they have been geologically active, but until we send probes to them they remain dwarf planets. Finally, in my view it is not an arbitrary criterion: having an active self-generated geology is a significant factor.
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When I was very young (5 or 6) my parents bought already space-mad me an Airfix 1:144 Saturn V model (and very kindly put it together for me). It was my pride and joy until it say on the back shelf of our car during a house move on a very hot day in 1975 and melted. My parents then even more kindly obtained and put together a replacement.

I soon got into model-making in my own right and recall making various other Airfix space kits (the 1:144 Space Shuttle and the 1:72 Lunar Module come to mind) but rather fell away from it when I got to play with computers.

Then, in 2010, as the result of a joke with [ profile] attimes_bracing I ended up building a rather silly customised 1:72 Avro Vulcan. I found it surprisingly good fun, and went on to put together a 1:48 F-117 stealth fighter. Then, at Christmas, my brother gave me... the Airfix Saturn V kit! Time to carry on with my revived hobby, and indeed revisit my youth.

Rocket Building, with large pictures )
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Via [ profile] daveon, a video of the latest test flight of SpaceX's 'Grasshopper' - a test vehicle for landing and reusing the first stage of the Falcon 9 rocket used to launch the Dragon resupply capsule to the Space Station.

Leaving aside the slightly cheesy choice of music, I'm very impressed by this. What SpaceX are trying to do is really hard. If you think about it, what you have is a a very large metal tank - a railway carriage would fit comfortably inside - that is mostly empty, and a rocket engine at the bottom. Not only are you trying to balance something tall and thin on a single engine's thrust, but the entire setup will be very sensitive to side winds. You now want to have this take off, climb, hover, and then descend again to land vertically.

Those of you who were watching space developments in the early to mid-90s may recall DC-X, a technology demonstrator for a vertical takeoff and landing rocket. Grasshopper is trying to replicate what DC-X did, but with a much larger vehicle that is likely to pose much greater control challenges.

So why is SpaceX trying to do this? DC-X was meant to be the first step towards a true single-stage-to-orbit (SSTO) launch vehicle, that would be completely reusable by virtue of not having to dump stages on the way up. But space launchers have stages for a good reason: it is very difficult to cram enough fuel to get to orbit into a structure light enough that a rocket can attain enough speed to get there. That's why rockets throw away parts of their structure on the way up. SSTO proved to be a dead end as it just didn't seem that anyone could realistically build a vehicle light enough to reach orbit, let alone carrying any payload. (DC-X showed that the takeoff and landing would work, but was very limited in performance, and I recall a rather acid comment that it was not so much SSTO as single-stage-to-six-thousand-feet.)

SpaceX isn't expecting to get all the way to orbit with a single stage. Instead, it wants to recover the first stage of Falcon 9 for reuse. The way it hopes to do this is to use some of the excess performance of the rocket to allow there to be some spare propellant left over at the end of the first stage burn. You might not think that would do a lot of good, seeing as how a few hundred tons of LOX and kerosene are needed to get the rocket to that point. But all that fuel went into accelerating the mass of the upper stage and payload. The separated first stage is mostly empty fuel tank, and it turns out that not much residual fuel is required to cancel out the speed it's gained and even send it back towards the launch site. Then, the last remaining fuel will in theory allow it to touch down back where it started, and it's that part of the process that Grasshopper is meant to test out.

On another note, I wonder what SpaceX used to film the flight? I can't believe a helicopter with crew would have been allowed anywhere near; perhaps one of those little remote-control helicopter cameras that seem to be all the rage for news-gathering?
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The bright meteor seen over the UK last week may have briefly been aerocaptured into orbit before entering again over North America.

This does look plausible. The 21 Sep fireball was very odd: it resembled a satellite re-entry in its relatively low speed and long duration, but was travelling the wrong way (east to west) and there was no known large orbital decay due. Speculation is that it may have been a very small asteroid in an orbit similar to the Earth's, which would account for the relatively low encounter velocity.

So far the analysis seems to have been based on visual reports and a few videos from ground-based observers. But this event will have been detected by the DSP missile-warning satellites and, given the object's trajectory, it ought to have been tracked by the BMEWS radar at Fylingdales - indeed, it must have gone almost overhead! I'm aware from my long-ago limited exposure to such systems that there is wariness about disclosing data that might reveal intelligence capabilities, but I wonder if there is scope for some suitably sanitised information to be disclosed that might help verify this intriguing hypothesis?
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How he could honour Neil Armstrong: ensure that there is never a point where no human alive has walked upon the moon.

There are now eight of twelve Apollo moonwalkers left; if Musk wants to show what SpaceX can really do, he can aim to land and safely return a human on a lunar mission whilst at least one of those moonwalkers is still alive. The youngest, Charles Duke (LM Pilot, Apollo 16), is 76 and two others are still in their seventies, so statistically he should have a decade or so to achieve this. Seeing as how he's gone in the last decade from Powerpoint presentations to flying return missions to the Space Station it's not beyond the realm of the possible he might manage it.
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Last week the US National Reconnaissance Office released a considerable amount of information about two of the second generation of US spy satellites: the high-resolution KH-7/KH-8 GAMBIT and the massive KH-9 HEXAGON. Among the materials placed online (although right now the relevant site seems down) was a programme history of GAMBIT; reading through it, I found the following remarkable snippet on page 81:

"On 20 May 1972*, ground stations lost contact with GAMBIT-3 No. 35 (which showed pneumatic-regulator failure) during ascent. As usual, an attempt was made to predict the impact point and a zone over South Africa was indicated. Five months later, Dr. Water F. Leverton, an Aerospace Corporation employee who had worked on GAMBIT-3, was visiting the London office of his company, where he heard that some "space material" had been found on a farm 75 miles to the north. He arranged a visit to the Royal Aircraft Establishment at Farnborough, where debris was displayed on a laboratory bench. He found three classes of objects: a spherical titanium pressure vessel, some circuit boards of US manufacture, and several chunks of glass which could be arranged into a pie-shape. The glass had the characteristic [REDACTED] used by Eastman Kodak and [REDACTED]** was convinced he was looking at GAMBIT debris. Eyewitness accounts also strengthened his belief: the objects had been seen falling to earth on 20 May. Discreet arrangements were made for the transfer of these materials to the United States, where they could take their place with the debris from CORONA No. 77 - another "errant bird" which had landed in Venezuela in 1964."

* The original text says 1976 but this is clearly a typo as a table in the same document says 1972 and other sources agree this date for one of the reported Titan-3B launch failures.

** An odd redaction as from context it must be Dr Leverton who is being referred to.

So what happened? GAMBIT-3 #35 must have very nearly made it into orbit to have got from Vandenberg, near Los Angeles, to England. Evidently an upper stage problem left it in such a low orbit that it rapidly re-entered, certainly before ground controllers could use its on-board orbit adjustment thrusters to stabilise the orbit as happened with one or two other such flights. Launched into a polar orbit, the ground track of GAMBIT-3 #35 would have been very similar to this plot of a more recent launch. Indeed, that shows that a Vandenberg launch into polar orbit flies over north-west Europe on the second revolution.

It sounds as if the NRO were aware that GAMBIT-3 #35 had limped into a very low orbit but that it had quickly re-entered. From that ground track, a guess of re-entry over southern Africa was reasonable, but evidently it lasted a dozen or so minutes more and actually must have re-entered over France, passing over the English Channel to break up and disintegrate over the Home Counties. Indeed, it must have narrowly missed hitting London itself.

The report is vague as to exactly where the debris was found. '75 miles north of London' covers an arc roughly from Corby round through Peterborough towards Downham Market. It would be interesting to search local newspapers for reports of satellite debris - or UFOs. I'm also wondering if an FOI request to the MOD might turn up any references to findings of satellite debris, or even a request from the Americans to return some bits of a rather sensitive project...
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(Via Making Light)

Ian Anderson and ISS astronaut Cady Coleman flute duet for Gagarin 50th anniversary:

alt link:
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I'm watching the live coverage of SpaceX's test of its Dragon reusable capsule.

So, I imagine is Elon Musk. Doubtless from within his hollowed-out volcano, whilst stroking a fluffy white cat.
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Robert McCall, noted space artist and illustrator, has died at the age of 90. Still working until very recently, he may be most familiar to sf fans for the dramatic poster artwork for 2001.

His style, although in some ways rather fanciful with its vapour trails and near-cloudscape nebulas, was both distinctive and very influential. McCall was very skilled at making space look like an environment rather than just a backdrop, and his work arguably inspired a generation of space advocates and hard-sf writers.
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When the Space Shuttle launches to the International Space Station - which, other than the recent Hubble servicing mission, is the only place it goes these days - the need to match the ISS' orbit means that its launch trajectory invariably passes over southern England about 20 minutes after take-off. If launch happens to have been timed such that it is early dawn or late dusk in the UK at the time, then it's quite likely that the Shuttle, being some 150-200 km up, will be in sunlight and so brightly illuminated and clearly visible from below.

Yesterday I noticed that the latest launch had been rescheduled, after a number of technical hitches, for midnight Florida time. That's 5am UK time, so the Shuttle, if launched, would be passing over the UK at 5.20. Right now, dawn is at around 6, so there was every prospect of seeing the Shuttle - if it launched on time, and if (a bigger if!) the sky was clear. So I set my alarm for 4.45...

Up, and a quick check of the mission status page; yes, the countdown is in its final minutes so I turn on the TV and watch what must have been a very spectacular night launch for anyone in Eastern Florida. A peer out the window shows the odd star in the London glare, so I pull on some trousers and a top and wander out into the car park. Dawn is clearly near, with the eastern sky brightening fast, but the Shuttle will be coming from the west, so I look that way.

And there it is. Two brilliant stars, each around about as bright as Venus (say magnitude -4 or so if you want to be precise), one white, the other a very obvious orange. The white one is the Shuttle Orbiter, the orange one its External Tank, now empty of fuel and separated some eleven minutes ago. About twice the width of the Moon apart, so say a degree or so, they pass overhead in a matter of seconds at perhaps twice the apparent speed the ISS usually moves at, a consequence of them both being much lower (some 200km, vs the ISS at nearer 400). In about another twenty minutes the Orbiter will burn its manoeuvring engines to place itself fully in orbit, whilst the ET will fall back to burn up over the Pacific.

I've never seen a Shuttle launch in person, and given that it's due to retire in another year or so, I doubt I will. But I think this comes close to counting.
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Prompted by a post by [ profile] daveon I found the list, as released by NASA after a Freedom of Information request, of books, films and TV programmes aboard the International Space Station (1.8MB PDF). Most of this stuff has accumulated by being brought up by individual astronauts, although I think some of the TV may have been uplinked.

Well, for one thing it's clear that there is at least one pretty serious Lois McMaster Bujold fan in the astronaut corps. Also an awful lot of David Weber, John Ringo (aaargh!) and Piers Anthony. Plus, about six months' run each of Analog and Asimov's, and a single Peter F Hamilton. (Mind you, given the cost-per-kilo to orbit, I'm surprised they managed to get even one of his up there.)

I remain disappointed that the list of DVDs aboard does not include Alien.
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The Kepler planet-hunting probe has demonstrated the clarity of its detection system by seeing not only the dip in light as a planet passes in front of its star, and indeed not only the dip again caused by the planet's own light as it passes behind, but the smooth increase in light from the planet as it's orbit takes it through the full range of phases.

This movie explains the light curve.

To me, that we are not only detecting planets a thousand light-years away, but actually measuring their changing phases as they orbit their star, is nothing short of amazing. I can also see some fun school-level science teaching from this, such as using the light curve to estimate the size of both the planet and the star.
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Anyone else thinking of going to tomorrow evenings 'Science Museum Lates'? It's got a space theme this month, and features a talk by Sy Liebergot, flight controller during Apollo 13.
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...although it is sped up from half an hour to about ninety seconds.

Space shuttle fly-around inspection of the Space Station, now with its fourth and final set of solar panels:

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Proposals made to solve Ares 1 rocket vibration worry

OK, that's the story written, I strongly suspect, from a NASA press release and putting, to say the least, a positive spin on things. Now, here's my take, and to establish my qualifications to pontificate, I have an MSc in space engineering and considerable experience in aerospace engineering analysis.

Why I'm not nearly so upbeat as that article )
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An excellent analysis in New Scientist on the approaching crisis for NASA arising from the fact that it's committed to buying post-shuttle space flights from a nation the US is no longer sure it's friendly with.

It's worth noting that the author is Henry Spencer, long regarded as one of the most sensible and well-informed space pundits online, right back to the days when all we had was one newsgroup.
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Laika, Nick Abadzis

Graphic novel, 208pp, £10.99.

A very good story, made only more poignant by knowing the ending.  )

Space Jobs

Feb. 13th, 2007 03:27 pm
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[ profile] fjm has just pointed me at this job advert from the National Space Centre.

It looks interesting, although having been round the NSC a few years ago I would be sorely tempted to add something to the job spec about ensuring that the science element of the education programme was both rigourous and relevant. (My take on it - their planetarium show in particular - was that there was a lot of GoshWow and not that much actual education. But then I'm an old-fashioned fart.)


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Simon Bradshaw

September 2017



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