Archive for the ‘Astronomy & Space’ Category
(Legally) Bombing The Moon
Still not much out of the LCROSS team, victims of “HYPErspace” to say the least. Let’s entertain ourselves in the intervening time with a Forbes.com article “Bombing the Moon“. And for those in a hurry:
The LCROSS mission is an important and expensive scientific experiment. Nonetheless, comments on Web sites such as Scientific American and Nature indicate that quite a few people thought the whole venture to be some sort of outer-space vandalism. Some even wondered whether NASA might have acted illegally or violated an international law or treaty by setting out to “bomb the Moon.”
The answer is no. But while many might be surprised–dismayed, even–to hear that there is such a thing as “space law,” there are treaties governing activities in outer space, including the Moon.
First Law of Planetary Building
First Law of Planetary Building: no two planets will ever be alike.
Corollary #1: if two planets are almost identical, then at least one of them will have at least one outrageously peculiar feature.
Corollary #2: Universes made of perfectly identical planets are not allowed.
The First Law is manifest in the fact that each planet in the Solar System and elsewhere appears to be a unique, very specific experiment with peculiar conditions that are never repeated elsewhere. Even single satellites are all very different from one another. And if you want to top strangeness, how about Corot-7b with its clouds of minerals?
One objection could be raised about Venus and Earth, or Uranus and Neptune, as both couples look like made of identical twins. However, Venus’s hellish atmosphere and very slow, retrograde rotation are truly outrageously peculiar features; and Uranus basically lies to one side (hence corollary #1).
Corollary #2 is necessary otherwise the First Law is invalidated. It seems plausible, since the number of universes is large but not infinite.
Going Back To the Moon: The Simplest Argument
It’s going to be far simpler to explore the Solar System with humans (and with robots) by starting from the Moon.
What is in fact at present the minimum requirement to reach orbit?
On Earth: Atlas LV-3B / Mercury (the one used in the John Glenn’s launch below)
Total Mass: 116,100 kg (255,900 lb)
Diameter: 3.05 m (10.00 ft)
Length: 25.00 m (82.00 ft)
On the Moon: Apollo Lunar Module Ascent Stage
Mass: 4,670 kg (10,300 lb)
Diameter: 4.2 m (13.78 ft)
Length: 3.76 m (12.34 ft)
Case closed.
The Tragedy Of The Anti-Space Travel Space Scientist
One can only feel sad upon reading Giovanni F Bignami’s op-ed piece about the race to the Moon and what choices to take for the future (“Once in a Blue Moon “, IHT, 18-19 July 2009). Prof Bignami’s argument appears to be about treating space-faring as a purely novelty product, like a fairly curious but ultimately useless item on a late-night TV shopping channel. Something you may be convinced to buy, but just the once.
And even if we have spent less than a week in total time exploring a few square miles of a place as big as the former Soviet Union, Prof Bignami tries to seriously argue that there is no “compelling reason” to go back to the Moon. And that we should embark on the enormous effort to reach Mars instead, presumably for a couple of trips before getting bored with travelling millions of kilometers too.
Here’s a “compelling reason” then: as it is well known, one needs a lot less fuel to travel to Mars from the Moon, than from Earth. Most of the launch cost lies in getting from our planet to low Earth orbit: beyond that, the whole planetary system is within relatively easy reach.
Prof Bignami remarks also that “the notion of mining on the moon would also [be] environmentally offensive“. I for one do not understand how will humans ever be able to “environmentally offend” a surface pummeled for billions of years by asteroids of all sizes, by a perfectly unhindered solar wind, and by cosmic radiations of all sorts. That is the Lunar surface, made of a type that likely covers several billion square kilometers on hundreds of natural satellites in our Solar System alone.
Paradoxically, the astronomical/astronautical community has been unable to support its own cause since the launch of the Sputnik. Nobody has gone anywhere because of effective lobbying by planetary geologists or solar scientists.
Bignami’s op-ed appears to be yet another example of how bizarrely brainy arguments about going to Mars vs returning to the Moon have succeeded so far only in keeping the human race in low Earth orbit, literally going around in circles instead of literally reaching for the stars.
The Large Hadron Collider Can Destroy Our World Indeed
The Large Hadron Collider (LHC) currently awaiting to be turned on at CERN in Geneva will not destroy the Earth. But it can destroy our world: by detecting definitive evidence for so-called “dark matter”.
Current cosmology indicates that the total amount of “dark matter” may be five times the amount of “normal” matter. As reported by Freeman Dyson on the New York Review of Books, the LHC is expected to find that “dark matter” is composed of the “supersymmetrical” equivalents of ordinary matter.
If the above is confirmed, it may be the first step towards making the world we experience as vanishing and irrelevant as a ghost in the desert at midday.
For all we know, there is a wholly separate “universe”, a “material world” coexisting with everything we can touch and see, with a lot more mass than ours, and getting by without much interaction with our “material world”, apart from gravity perhaps.
Imagine a “dark matter telescope” showing a completely different sky. Like Nicole Kidman’s character in “The Others”, it will be the revelation that the ghosts, it’s us.
And Plato would be very proud of himself.
Nature Geosciences – “Planetary” Issue Free To Download
The April 2009 issue of Nature Geosciences, focused on “Planetary Science”, is free to download, at least for now.
There is also a feature article by Paul Spudis on returning to the Moon.
Collapse Expected In The Number of Candidate Astronauts
From Slashdot
“Science reports that silkworms may be an ideal food source for future space missions. They breed quickly, require little space and water, and generate smaller amounts of excrement than poultry or fish. They also contain twice as many essential amino acids as pork does and four times as much as eggs and milk. Even the insect’s inedible silk, which makes up 50% of the weight of the dry cocoon, could provide nutrients: The material can be rendered edible through chemical processing and can be mixed with fruit juice, sugar, and food coloring to produce jam.”
Principles For A Mars Transport System
The following text, by Stephen Ashworth FBIS, has been presented at the British Interplanetary Society’s “Ways to Mars” symposium, held on 19 November 2008 at the Society’s London headquarters. Its main points:
– Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;
– But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because [the paradigm] excludes the construction of permanent human activity in space.
The text is published here with the consent of the author. More from Mr. Ashworth at his website.
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Transport for Areopolis Or: “Implications of the Choice of Economic Paradigm for Strategies of Manned Access to the Moon and Mars”
by Stephen Ashworth
When considering human access to Mars, it seems to me that there are two key points which need to be taken into account, but which are often ignored. I shall offer you these two points very shortly.
Designs for manned missions to Mars typically involve assembling in low Earth orbit a spaceship weighing several hundred to over a thousand tonnes.
For example, each Troy spacecraft, which we shall be hearing more about this afternoon, weighs nearly 800 tonnes to carry 6 astronauts. The “space lego” nuclear powered Mars mission uses two ships of 240 tonnes each, thus a total of 480 tonnes in low Earth orbit. [I was wrong -- this turns out to come to a total of 955 tonnes.] The “magic” Mars mission requires five Energiya launches, thus probably weighs 4 to 500 tonnes when ready to go.
Meanwhile the official European Space Agency design study for a Mars mission proposed a ship, again for 6 astronauts, which required 20 Energiya launches for every single Mars departure. These launches would build up a ship weighing 1357 tonnes at departure.
The Mars ship in low Earth orbit thus weighs between about 50 tonnes and about 200 tonnes per astronaut on board. Launching such large masses into orbit for the benefit of so few people is one reason why manned Mars exploration is hopelessly uneconomic.
At present-day cargo rates to low Earth orbit of $10 million per tonne, this is a billion dollars per astronaut, plus the cost of the Mars hardware itself. Even at spaceplane rates, which may fall to as low as $10 thousand per tonne, this is still a million dollars per astronaut, plus the cost of the hardware.
At these rates, there will not be many people going to Mars.
Let me show you an Earth-Mars transfer orbit.
Here is an orbit which reaches out from Earth to pass the orbit of Mars. It has about the same size and shape as the orbit of an Earth-Mars cycler, such as the ones being studied by Buzz Aldrin and his collaborators.
It might therefore be the orbit of a future manned Mars vehicle. But that’s not what I drew. What I’m showing you here is the orbit of minor planet 4660 Nereus.
The concept of an interplanetary cycler, which repeatedly encounters Earth and Mars, goes back to the early 1980s. Alan Friedlander and John Niehoff first proposed setting up long-lived space habitats which remain permanently in interplanetary space. These would periodically be used for transporting people between Earth and Mars. Relatively small ferry spacecraft would complete the transport chain between the cycler and a local parking orbit or planetary surface.
In 1985 Buzz Aldrin added the concept of a gravity assist at each planetary flyby. This technique allows a cycler to stay in phase with the relative motion of Earth and Mars. It enables it to offer passage between these planets once every 2.14 years, the Earth-Mars synodic period.
A great number of near-Earth asteroids, such as 4660 Nereus, resemble natural Earth-Mars cyclers. A proportion of them are believed to be carbonaceous chondrites, containing water and other volatiles. Water in space is of incalculable value as a feedstock for propellant manufacture, as a near ideal substance for radiation shielding, and for other life support functions.
I have checked the online listings of near-Earth asteroids published by the Minor Planet Center. Applying quite stringent orbital criteria, I found a total of 56 Amor and Apollo asteroids which behave like natural Earth-Mars cyclers. New ones are being discovered all the time — for example, of those 56, ten were only identified this year.
Now to my two key points.
Firstly: most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials. That mass is already in space, and already in orbits very close to the ones which we will need to reach and return from Mars. It does not need to be launched from Earth. It can be mined in situ.
So why is hardly anybody getting excited about this? Why does it not form the basis of the Constellation programme, or of the recent ESA or Russian design studies, or even the magic, the trojan or the space lego Mars missions?
Because of my second point: the asteroidal resource is completely invisible to the space agency paradigm of space exploration. That mode of planning excludes the possibility of systematic use of natural in-space materials, and it excludes the construction of permanent infrastructure on Earth-Mars cycler orbits. It will not contemplate anything that suggests permanent human activity in space.
I think we can identify two broadly contrasting attitudes to transport infrastructure.
The heroic paradigm is only interested in special missions of heroic exploration. This is the space agency mode of thinking. Its prime goal is national presige, under a fig-leaf of science, spinoff and educational inspiration. Think of the Apollo programme. Further back in history, think of Zheng He’s epic voyage of exploration around 1421, from a China which was about to close in on itself.
In contrast with the heroic paradigm, we can identify the systemic paradigm of transport infrastructure. The prime goals here are permanence, growth, and economic profitability. Think of the Cunard and White Star steamers which connected Britain with the Americas and the Empire from the mid-nineteenth to the mid-twentieth century.
Now obviously, since there is currently nobody on the Moon or Mars, the next people to travel there will of necessity be heroic government explorers. But the question we need to address is this: will their transport system be designed for cancellation, like Apollo, or will it be designed for growth, like Cunard?
What would a systemic manned space transport system look like?
I have identified four key features.
Firstly, it will employ reusable spacecraft — an obvious enough point.
Secondly, it will not be content with a single route — say, between Kennedy spaceport on Earth and a single base at Utopia Planitia on Mars. It will rather seek to foster a network of different routes among a number of different transport nodes. Those nodes may include an increasing number of space hotels, factories and laboratories, and lunar and martian bases.
Note particularly that the use of transport nodes allows in-space refuelling. This capability was regarded by early spaceflight theorists such as Hermann Oberth and Guido von Pirquet as essential if lunar and martian flights were to become achievable using chemical fuels.
Thirdly, a systemic space transport system will diversity its sources of propellants and life support materials, exploiting the transport nodes for in-space refuelling.
Fourthly, it will not be content with a pillar architecture, but will develop a pyramidal one. In a pillar architecture, one unique space station is succeeded by one unique Moon base, and that in turn by one unique Mars base. In a pyramid architecture, by contrast, it is growth in the use of space stations that supports the first Moon base, and growth in the use of Moon bases that supports the first Mars base.
Thus in impressionistic figures, if there are ten people on Mars, then we should expect to see at the same time at least a hundred people on the Moon, and at least a thousand on board stations in Earth orbit at any one time.
So we can now design a Mars transport system along the following principles:
– The long-haul journey is accomplished on modular interplanetary cycler stations, which are upgrades of stations in regular use as Earth-Moon cyclers, which are themselves upgrades of stations in regular use in low Earth orbit as hotels, factories and so on;
– The transport chain between Earth and the interplanetary cyclers is closed by short-range ferries, which are upgrades of ferries in regular use to connect with the Earth-Moon cyclers, which are themselves upgrades of ferries in regular use between Earth’s surface and low Earth orbit;
– The bulk of the development work that goes into the first Mars mission is carried out by commercial companies in pursuit of profitable business in space tourism, manufacturing and energy;
– As a result of growth in traffic in the Earth-Moon system, an in-space refuelling system based on near-Earth asteroidal water will become economically viable, vastly decreasing launch costs from Earth.
There may still be a heroic attempt to get to Mars in isolation from the development of such a space economy. If we are lucky, it will be like Apollo, and will be cancelled after the first few landings. If we are unlucky, it will be like the X-33 or Hermès spaceplanes, or like the Soviet Moon-landing programme, and be cancelled before its first landing.
Either way, it will not produce much progress towards sustainable human access to Mars. That can only be achieved by a systemic transport system, not a heroic one.
To conclude, I would remind you of my two key points:
– Most of the mass needed for an Earth-Mars transport system consists of propellants and life support materials, and that is already in space, and already in orbits very close to the ones which we need;
– But this near-Earth asteroidal resource is completely invisible to the space agency paradigm of space exploration, because it excludes the construction of permanent human activity in space.
Thank you.
Phil Plait’s Moon Hoax London Speech – Report
I had the honour to attend tonight in London a speech by Phil Plait “The Bad Astronomer” on the “Moon Hoax Hoax” (i.e. the hoax perpetrated by those that believe the Apollo manned lunar landings were a fake).
The presentation was organized by the UK’s Skeptic Magazine as part of their Skeptics in the Pub’s monhtly gathering, taking advantage of Plait’s schedule in-between his Colorado home and a visit to the Large Hadron Collider in Geneva.
In front of a large crowd downstairs at the Penderel’s Oak in Holborn, Plait chose to wear a hat after dazzling us with an impressive hairdo (or lack thereof).
So how to respond to people still clinging to the odd notion that NASA has been able to pull off a multi-decadal hoax involving tens of thousands of people, something much more difficult that actually landing on the Moon itself? The Bad Astronomer went through familiar questions and answers, here summarized:
(1) No stars in Moon photographs? Obviously not. Those are pictures of bright spacesuits and a bright terrain directly hit by the Sun’s rays.
(2) Shadows are not parallel, “demonstrating” multiple light sources? First of all, multiple light sources cause multiple shadows, and there is none of that in the Apollo pictures. Furthermore, shadows are not parallel on Earth either: it’s called perspective!!!
(3) Astronaut’s suits in the dark shadows on the Moon are not black? Of course not, they are illuminated by the surrounding, bright lunar surface.
(4) Waving flags on the Moon? Sure, with nothing much to dampen any vibration, that’s exactly what to expect.
(5) No crater from the LEM’s landing engine? Large thrust, over a large surface, means low pressure, hence…
(6) No flames from departing LEM’s upper half in Apollo 17 video? Flames are only visible for certain types of rocket fuel. Even the Space Shuttle’s main engines produce a barely visible blue flame at take-off.
There are two main problems with “moon hoaxers”: one, as Plait pointed out, is that they choose to tell only that part of the truth that suits them. The second, if I may add, is that they invariably never ever reveal what evidence would convince them to change their mind.
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I have only one remark for the Bad Astronomer: sometimes he goes too hard for it. All Moon-hoaxers’ claims I have seen so far are already ridiculous enough. Is it really necessary to build jokes around stuff that is already laughable on its own?
Anyway…it’s been great to meet somebody that enrolled me some time ago as one of his minions. Here some pictures from the evening…
Space Elevators as Launch Platforms
It is not widely appreciated that Arthur C. Clarke’s idea for a “space elevator” is not just useful to reach Earth orbit: it can become a way to launch probes and people around a large part of the solar system with little fuel consumption.
In fact the elevator’s end at geostationary level (36,000 km) moves at 11,000 kph, that is 3 km/sec. At that height, the Earth escape velocity is 4.23 km/sec, so a relatively small “nudge” is needed to leave Earth.
That is not all. If the elevator is extended to 46,000 km, the “terminal” velocity equals the escape velocity (3.8 km/sec): therefore making launches even simpler and cheaper, more or less “free”.
The maximum theoretical limit is the L1 point between Earth and Moon, where their gravitation pulls equal each other. Situated around 260,000 km away from the Earth’s surface, an elevator terminal that far would travel at 20 km/sec, more than enough to reach Mars. And that, without allowing for various techniques that could make the launch speed even larger.
Stop NASA’s Life Fixation
There is so much still to explore in the Solar System, and an untold number of astonishing discoveries just out of sheer serendipity…and yet, the only thing that matters for NASA is the possibility of life???
Whatever the source of Enceladus’s fountains, it is obviously very well worth the effort to find something about it.
The Elementary Coincidence of Watson and Holmes
Has anybody else noticed that Watson, the DNA structure discoverer, has “switched off the lights upstairs” just as Holmes, the comet, has brightened up almost a million times?
Crowds, Echoes and Communication with Parallel Universes
The existence of a Multiverse has many philosophical consequences (and it just makes so much more physical sense than having us living in a Goldilocks Universe). And as the Multiverse has been postulated from actual observations, we can almost say we can test its existence.
Of course it would be all much more interesting if we could talk to a parallel universe.
Or would it? Communication between Universes may actually be made rather difficult by a “crowding echo effect“.
Imagine I were to try send a message via a quantum interference pattern, for example.
Obviously, all my quasi-identical copies from “nearby” parallel universes quasi-identical to my own Universe, would be trying to send quasi-identical information via quasi-identical ways at quasi-identical times: so we could all be creating so much noise as to make the reception of any message next-to-impossible.
Even more paradoxically, we could actually be reading each other’s message: but since those messages would all be quasi-identical to each other, we could mistakenly convince ourselves that we were listening each one only to his own echo.
After all what meaningful information could anybody exchange with a quasi-identical copy?
It may take a very very long time to figure out the minute differences between the two and those may as well be undetectable or absolutely irrelevant.
Venus Forecast
In a few years, the old ideas of Fred Singer will come back into fashion.
Venus’ retrograde rotation, incredibly massive atmosphere and relatively young (<500 million years) surface will be elegantly explained by the crash of a massive satellite half a billion years ago (with subsequent melting of much if not the whole crust, and humongous outgassing).
Current lead-melting surface temperatures will be just as beautifully explained by simple adiabatic processes.
The role of CO2 in the heating of the atmosphere via some “greenhouse effect” will be seriously reconsidered and almost completely dismissed.
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Some quick computations:
Ratio of available solar energy Venus/Earth: 190%
Earth, surface pressure: 1000 mbar; temperature: 288K
Venus, 50km altitude pressure: 1000 mbar; temperature: 330K
330K/288K = 114% < 190%
Venus, surface pressure: 90,000 mbar; temperature: 735K
Temperature of terrestrial air compressed from 288K/1,000mbar to 90,000mbar: 887K
735K/887K = 82.9% < 190%
Far from showing any CO2-induced global warming, Venus is much cooler than expected, likely because of the high-altitude clouds that prevent us from looking at the surface.
Pretty Awful Astronomy on Astronomy Magazine
Astronomy Magazine’s latest Collector’s Edition issue “50 Greatest Mysteries in the Universe” (ed: David J Eicher) is even more special than usual, unintentionally so given the width and breadth of its errors.
With mistakes ranging from excessive simplifications to incredible blunders, it is just too tempting to wonder about Mystery #51, namely “Does anybody do any proofreading at Astronomy Magazine?”
Here’s a list of what I have spotted so far, starting from the biggest howlers:
Question 36: “Could a distant, dark body end life on Earth?”: (page 73):
“Among them are the Sun-like star Alpha Centauri”
Egregiously wrong. Alpha Centauri is not a single star. In this case, the text does not show the most elementary grasp of astronomical knowledge.
Question 31: “Does inflation theory govern the universe?”: (page 62):
Under caption titled “Minuscule Time”
“…compare 1 second to the 13.7-billion-year-age of the universe. Next, divide that 1 second into an equivalent number (13.7 billion) of parts…”
Egregiously wrong. The text mistakes “years” for “seconds”. This is quite worrying as it is trivial to understand that the correct “equivalent number of parts” is 31 million times larger: that is, 13.7 billion years times 365 days a year times 24 hours a day times 3600 seconds per hour.
The result is 4.32*1017, definitely not 13.7 billion.
Question 19: Can light escape from black holes?”: (page 41):
“1067 years, or more than one million times longer than the whole history of the universe to date”
Egregiously wrong. If the Universe has been around for 13.7 billion years, that’s 7.3*1056 times less than 1067. That number is 730 billion quadrillion quadrillion, not just “one million”.
Looks like whoever did the computations, misread 1056 into 106. Or worse.
Question 6 “How common are black holes?”: (page 18):
“Encountering a black hole of any type, your body […] would be pulled into a very long line of protons”
Wrong. If one were shielded against radiation, falling into a sufficiently large black hole would entail experiencing relatively weak gravity gradients.
Question 8 “Are we alone?”: (page 21):
“Viruses…’life’ – which for them amounts to cannibalizing cells”
Wrong. Only some viruses kill the host cells: many of them are more like non-lethal parasites (I am leaving aside the fact that cannibals eat their own species, and that’s not what viruses do).
Question 42: “What will happen to the Sun?”: (page 82):
“As the swollen Sun incinerates the solar system’s inner planets, its outer, icy worlds will melt and transform into oases of water…”
Mostly wrong. That is, true only under extraordinary conditions. Liquid water can exist only at pressures above Water’s Triple Point’s (661 Pa). And so it will only appear on those satellites and asteroids capable to maintain at least that much atmosphere.
How many will? Not many, perhaps just a handful or none at all.
Question 13 “Will asteroids threaten life on Earth?”: (page 30):
“The destructive power a rock carries to Earth is directly proportional to its size”
Oversimplistic. Roughly, the consequences of an asteroidal impact are directly proportional to its mass. But this leaves out other considerations, including the asteroid’s chemical make-up, density, shape, atmospheric entry angle, and more.
Question 6 “How common are black holes?”: (page 16):
“If you could throw a baseball at a velocity of 7miles per second, you could hurl it into space”
Oversimplistic. As the baseball would have to go through lots of air at first, the initial speed must be considerably larger, for a simple throw (even leave aside all considerations about heating by friction). This may look trivial, but considering the other errors in the magazine, one is left with the lingering doubt that the 7mi/s figure may have been not just a simplification.
Question 2 “How big is the universe?”: (page 10):
“…we live in a Universe that is at least 150 billion trillion miles across…”
Antiquated. The galaxies we observe as 10 billion light years away have obviously had 10 billion years to move away much further by now, and that is not all. By considering additional effects such as post-Big Bang inflation, and the acceleration of the expansion of the Universe, the actual value for the size of the Universe may be in the region of 160 billion light years
And finally…
Question 2 “How big is the universe?”: (page 10)
“Other universes might exist beyond our ability to detect them. Science begs off this question…”
Question 3 “How did the Big Bang happen?”: (page 12):
The often-asked question ‘What came before the Big Bang?’ is outside the realm of science”
Antiquated. For a more up-to-date view, check http://news.bbc.co.uk/1/hi/sci/tech/4974134.stm and Science magazine
All in all: plus 50 points for the magazine’s idea, but minus several million for being so careless with the stuff they are supposed to know more about…
Drawback In The Sad “Dwarf Planet” Saga
Size does matter for NASA, ESA and the likes. That’s the drawback.
This summer, 49 years after being established, NASA will launch its first major space probe dedicated to the study of main-belt asteroids Ceres and Vesta.
In the meanwhile, in 46 years of interplanetary travels there have been only a couple of Russian attempts at studying Phobos, the satellite of Mars that is likely to be a captured asteroid.
And none at all about Deimos, the other satellite of Mars, despite the fact that it is the easiest and cheapest place to reach in the Solar System from the Low Earth Orbit (such as the Space Station’s). It’s easier and cheaper than the surface of our own Moon.
Can’t anybody else see a pattern emerging? Yes there have been peculiar missions like the one to asteroid Eros, but those are by far the exception.
Let’s face it: Big Space Agencies don’t like to bother with small components of the Solar System. It is not “cool” enough to say “Well guys and gals we are going to see a space rock smaller than Rhode Island” (despite the surprises those space rocks may be hiding for us to discover).
There is a mission en-route to Pluto now. It was cancelled before lift-off at least once, and I am sure it would have never been approved had Pluto been demoted to “dwarf planet” in that silly astronomical congress a few months back.
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And all of that, just to make sure schoolchildren could keep a mnemonic of 8 planets?
There are more than 9 stars and more than 9 galaxies…
The more time passes, the more unbelievable the whole thing is. Now Eris has been discovered to be larger than Pluto.
So what?
Anyway, I think 99.99% of people will agree that there is no way to scientifically define a planet. Here’s a definition for the “Average Joe and Jane” then:
“A Planet is a round-ish object that orbits around a star and does not orbit around another round-ish object” (c) Maurizio Morabito 2007.
Who can get simpler than that?
And what would be soooooooooooooo wrong with it?
Return to the Moon – a Guessing Game
It was refreshing to see Dwayne A. Day start his “Outpost on a desolate land” article with pragmatic words about calendar slippages in NASA’s return to the moon (on the British Interplanetary Society’s “Spaceflight” magazine, May 2007).
One has just to look at the history of the Space Shuttle and then the International Space Station, compared to the Apollo project, to understand that big space projects without fixed deadlines will cost a lot more than anticipated, and achieve (much later) a lot less.
Some say that’s the way Governments work.
Is there perhaps a case for launching a “Moon Landing” competition, with a prize for whomever will guess the date of the “seventh American landing” (and another for the “first Chinese landing”)?
My entries are the following:
a. Without another Space Race, NASA will finally land again on the Moon on July 11, 2069 (mostly, to avoid feeling ashamed of themselves)
b. With a Space Race with the Chinese, American astronauts will walk on the Moon around July 11, 2029
c. Chinese taikonauts, if things get serious, will reach the Moon around July 2027
Nothing to be enthusiastic about, but what’s the point of deluding ourselves into believing that things will be any faster?
Unless there is some major breakthrough in commercial space activities beyond LEO…
The Average Brit Flying to Work at 18,000mph
So what is my local car rental manager doing, parading in NASA coveralls in London’s Queen Mary University Theatre in late November 2006?
No, wait: it must be Gary Lineker, guest speaker of the British Interplanetary Society, with a 8’-by-5’ poster of Saturn and the secret aim of taking chips and sweets from the noisy local student contingent.
Or…is that a bird? Is that a plane? No, it’s Piers J. Sellers, Ph.D., former Global Warming researcher and now Space Shuttle crew member and quasi-UK Astronaut Extraordinaire (“quasi” as UK persons need opt for a different citizenship to work in Earth orbit).
Sellers, born in Sussex in 1955 but now an American citizen, is following up his July STS-121 mission with a UK trip that has generated good-natured interest in the press, and even some air time on BBC Radio4’s Today.
Luckily (for Sellers) and blissfully (for all of us), Sellers’ Shuttle trip companion astronaut Lisa M. Nowak hasn’t yet destroyed her career by wearing nappies for a 1,000-mile drive to pepper-spray a love rival in February 2007.
And so instead of a sex scandal, the talk is about the less risky enterprise called space travel, as told by a bloke so average in appearance and so relaxed about himself to make taciturn Neil Armstrong a veritable space alien.
“Aliens won’t invade us, because [on streets like Mile End Road] they can’t find where to park”: Sellers is definitely no warplane pilot turned moonwalker spiritualist. He’s “simply” a space walker, slightly “disoriented” only by the first sight of the white-and-blue jewel called Earth.
His description of the piling up of task upon task may sound familiar to office workers the world over. Still, very few of those usually validate if their cubicles will destroy during atmospheric re-entry, as Sellers and the rest of the STS-121 crew did after the Columbia tragedy of February 2003 and the half-botched first “return-to-flight” mission of STS-114 in July 2005.
A NASA video hints at the peculiarities of working in space. First of all there is nobody within a 3-mile radius of a ready-to-start Space Shuttle: and for good reason, as the bunch of aviation and navy pilots, space commanders and Ph.D’s collectively called “astronauts” are literally sitting on top of a giant bomb hoping it will explode in a controlled manner, pushing them upwards and forwards rather than into smithereens..
There is lots of sound and bouncing at lift-off. Somebody touches a control button, but Sellers reassures “We were just pretending to work. The launch [really] blew me away.” Orbital life is a piece of cake in comparison, with a couple of days of procedures to proceed and checklists to check, before approaching the International Space Station at the snail-like pace of 1m/sec (a little more than 2 miles an hour).
The video recording moves on to Lisa Nowak working with a large boom, at the time not to threaten a love rival but to move cargo to the Station with fellow astronaut-ess Stephanie Wilson, and then finally on mission day five maneuvering Sellers and colleague Michael Fossum locked on top of a 100-foot pole.
Sellers recounts a few funny details. For example, even in the most comfortable spacesuit one better gets used to spending up to ten hours without luxuries such as toilet breaks and nose scratching. And so a big deal of one’s resting time is spent cleaning up bodily odours and outpours from the spacesuit (no mention of any solution to the nose itching problem).
Furthermore, gloves for orbital work are more apt for a The Thing impersonation from the Fantastic Four, and so one handles multi-million-dollar wrenches knowing some will drop on their own sidereal orbit. Last but not least, one gets occasionally stuck in a phone-boot-like airlock for more than one hour.
Back inside the spaceship, in-between risky zero-g adventures with M&M’s of all things, one can look forward to a “shower” of damp cloths, a dinner of bland food and a night chained to a bed (kinky orbital fun, anybody?). Ah, and the toilet has a noisy fan and too thin a door really.
After some four days of that, it’s time to pull the jet brakes on the Shuttle (“feeling like on a truck slowing down”, Sellers remembers) to start the “unforgiving landing sequence”, after gulping in a disgusting salty drink designed to help the body readjust to Earthly life.
Outside the vehicle, “cherry-red windows” show the same tongues of fire that consumed the unfortunate Columbia astronauts a mere three-and-a-half years earlier. Falling almost helplessly, the Space Shuttle is somehow guided without engines to a hard touchdown, at the end of which gravity is felt like having “brick on the shoulders”.
Still Sellers opines, “The real dangerous bit is the lift-off.” No need to remind anybody of the crew of six that died on the 1986 Challenger accident, during the ascent phase.
Has Sellers got any chance of going back to the Space Station? “Sure. There is plenty of work available,” he answers. “Perhaps there will be 15 missions with 7 astronauts each between now and 2010.” Such chances are presumably slightly larger now than Ms. Nowak has been removed from NASA’s roster.
Before a strange, nostalgically catchy set of photographs of Seller’s mission is shown to the tune of Coldplay’s “Speed of Sound”, the evening fades away in a torrent of questions about medical facilities (“We can’t do heart transplants in space as yet”); rubbish management (“Thrown overboard”); launch delays (“Frustrating”); the justification for space budgets (“The money is spent on Earth”); and Orion, the Space Shuttle replacement (“Safer and cheaper and brings us back to the Moon”).
There! Has anybody else caught the tiny sparkle in Sellers’ voice when mentioning future manned Lunar exploration? Who knows, by 2025 the UK government may have found the negligible additional resources to fund a trip to the Moon for a couple of lucky British passport holders.
For the time being, I better check if my local car rental manager has moved to Houston.
Oldies to the Moon!
Larry Kellogg has more details on the issue of protecting people when working on the Moon (see my previous blog “Where to Build Inflatable Lunar Structures“).
In my paper on the topic I reported the recommendation of a protection for astronauts of a minimum 4 meters of regolith (lunar soil).
As correctly pointed out by Larry, the issue is that thinner shielding with aluminum-reach lunar regolith could actually be more harmful than beneficial. Fast-moving energetic particles raining from space and hitting too thin a layer of regolith would generate slower but not stop “secondary emissions” that would then interact more with human tissues such as the blood.
As plastics or water stop the radiation particles with considerably fewer “secondary emissions”, they may provide more protection with considerably less thickness.
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How much protection is actually needed? On Earth, the general public should receive less than 0.5 rem/year. For those who work with radiation, the maximum is 5 rem/year.
It turns out that space projects allow for Astronauts to be cooked with a maximum of 50 rem/year. Somehow, this 100-fold increase on what our bodies were evolved to tolerate is not expected to cause much harm.
Perhaps, the very people that suggest that, they should be volunteered for experiments as human guinea pigs.
Sometimes in 2008, the Lunar Reconnaissance Orbiter probe will provide some more information. There is lots to investigate indeed.
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For the time being however, we can play it safe.
It is well known that people above a certain age can more reasonably run the risk of exposure to higher radiation doses, if only because they have a higher chance than younger persons of dying of other causes before developing any kind of radiation-induced tumor.
How about selecting “oldies” as Lunar Astronauts then? Given expected life spans, anybody above 70 would do.
For a candidate for a lunar trip in 2037 and beyond, look no further than to the author of this fantastic blog.
Where to Build Inflatable Lunar Structures
CosmicLog (read through Larry Kellogg’s “Lunar Update” mailing list) has an interview about innovative lunar structures with Robert Bigelow of “Inflatable Space Station” fame.
Bigelow does mention of an idea on how to bury the structure (but only with a couple of feet of soil, not the 12 or more required).
In fact the thought of spending more than a couple of days virtually unprotected on the Lunar surface should not enthuse anybody. It has been computed (*) that on average a maximum 20% of time should be spent by humans outside the protection of a minimum 4 meters of regolith.
(*) R Silberberg et al, ‘Radiation Transport of Cosmic Ray Nuclei in Lunar Material and Radiation Doses’, in W W Mendell, ed, ‘Lunar Bases and Space Activities of the 21st Century‘, Lunar and Planetary Institute, 1985, p668
Bigelow is right and wrong at the same time. If we seriously consider going back to the Moon, resources should be spent investigating how easy it will be to bury those Habitats (inflatable or otherwise).
But excavated regolith is only one option and not the most practical one given the amounts of soil that will have to be moved to make comfortable living out of a stay on the Moon.
Other ideas involve lava tubes, of which there should be aplenty, and artificial giant caves. Especially the caves should be easy to create with explosives, if there is no water in the lunar rocks.









