Filed under: Astronomy, Bad Astronomy, Failure, Government, ISS, movies, NASA, Phil Plait, Predictions, Science, Science Fiction, Space, Star Trek, Survival, tech, Travel, UFO
This item made the news yesterday:
Scientists eye debris after satellite collision
CAPE CANAVERAL, Fla. – Scientists are keeping a close eye on orbital debris created when two communications satellites — one American, the other Russian — smashed into each other hundreds of miles above the Earth.
NASA said it will take weeks to determine the full magnitude of the unprecedented crash and whether any other satellites or even the Hubble Space Telescope are threatened.
The collision, which occurred nearly 500 miles over Siberia on Tuesday, was the first high-speed impact between two intact spacecraft, NASA officials said.
Wow: two satellites have collided in orbit, destroying both. This is the first time such a major collision has ever occurred.
The satellites were Cosmos 2251, a Russian communication relay satellite that’s been defunct for a decade, and an Iridium satellite, one of a fleet of communication satellites launched by Motorola in the late 90s and early 2000s.
* * *
There have been collisions in space before, but never from such large satellites — the Iridium bird was about 700 kg, and the Cosmos was about the same — and never resulting in a total wipeout like this. Again, if I have my numbers about right, the explosion resulting from the energy of impact would have been about the same as detonating a ton of TNT.
I had to chuckle at this comment in that thread at Bad Astronomy:
But wouldn’t the impact have made a new, ever more powerful hybrid satellite? It would have an over-arching need to communicate and would do so in Russian. The only way to make it stop broadcasting a constant barrage at us would be if it mistook someone for its designer at Motorola and then. . . Oh wait, this isn’t Star Trek.
No, not at all. When you have two large satellites, each moving at something on the order of about 5 miles a second hit one another at nearly right angles, then you don’t get any kind of hybrid. You get a mess. As in a debris cloud of upwards of a thousand bits and pieces of space junk, some of it substantial, most of it still moving at thousands of miles an hour, and all of it dangerous.
I’ve written previously about the threat of real ‘UFOs’ to our space exploration. From the quoted article in that post:
The reason is life-and-death. Since Mercury days, NASA engineers have realized that visual sightings of anomalies can sometimes provide clues to the functioning — or malfunctioning — of the spaceships that contain their precious astronauts. White dots outside the window could be spray from a propellant leak, or ice particles, flaking insulation, worked-loose fasteners (as in this latest case) or inadvertently released tools or components.
Whatever the objects might be, they pose a threat of coming back in contact with the spacecraft, potentially causing damage to delicate instruments, thermal tiles, windows or solar cells, or fouling rotating or hinged mechanisms. So Mission Control needs to find out about them right away in order to determine that they are not hazardous.
Right now the bulk of that debris cloud is about 250 miles higher than the ISS. But it will slowly drift closer (the effect of atmospheric drag – even at that altitude, it will slow anything in orbit, meaning that the item in question will drop to a lower orbit). At some point, this could be a real threat to the space station.
And beyond that, it is a further complication to *any* effort to get into something other than a low Earth orbit. Currently we have something like tens of thousands of bits of “space junk” that have to be tracked – and while all of it will eventually fall back into the atmosphere and burn up, it can present a real danger. If we’re not careful, we could encase ourselves in a shell of so much junk that it would basically eliminate the possibility of travel beyond our planet for decades.
Jim Downey
Filed under: Apollo program, Art, Astronomy, General Musings, NASA, NPR, Science, Space
The rocket blasted off with a huge spread of flame and hurled the men into space. They became the first earthlings to watch their home planet grow smaller and smaller and smaller, until it was floating far away and tiny in the darkness.
From this morning’s NPR coverage of the Apollo 8 mission to orbit the Moon 40 years ago. Most of the world remembers it best thanks to Earthrise, the iconic image from the mission, which gave us all a new perspective of our fragile little home.
It’s a good story. As I said elsewhere in a discussion of my memories from the event, I expect there will be few other such moments in my life.
Jim Downey
Filed under: Astronomy, Fermi's Paradox, Marketing, Pandemic, Plague, Predictions, Science, Science Fiction, Society, Space, Survival, Writing stuff
Yeah, I know I said I’d try and get a nice cheery travelogue up next. Oh well. This has more relevance to Communion of Dreams, which is ostensibly the focus for this blog, anyway, right?
Right. So, here: seems that researchers have for the first time clearly determined the extinction of a mammal to have been caused by disease.
In 1899, an English ship stopped at Christmas Island, near Australia. Within nine years, the island’s entire native rat population had gone extinct, and scientists have wondered ever since what exactly happened.Now, researchers led by an Old Dominion University scientist think they have unraveled the mystery – and, they say, the lessons of Christmas Island apply today to issues such as disease, invasive species and the law of unintended consequenceTurns out, says ODU biology professor Alex Greenwood, that a British black rat had stowed away on the ship in a bale of hay. Upon reaching the island, the rat – or several rats – escaped on land and spread a “hyperdisease” among the native population.“Anyone who has ever tried to kill a rat – let alone a whole population – knows how hard that can be,” Greenwood said in an interview Monday. “That’s what made Christmas Island so fascinating for so long. Imagine, a whole species – especially one as tough as a rat – gone within 10 years of exposure!”
OK, for those of us who are non-biologists, this may be something of a surprise: why wouldn’t extinction occur due to disease? But the prevailing theory has long been that it was virtually impossible that a disease would wipe out all members of a species – and that any survivors would pass on their immunity to their descendants, thus continuing the Darwinian arms race. To determine that this has happened – and to a robust and fast-reproducing species such as a rat – is real news.
Which touches on an older item I came across recently:
Reducing the Risk of Human Extinction
Jason G. MathenyAbstract: In this century a number of events could extinguish humanity. The probability of these events may be very low, but the expected value of preventing them could be high, as it represents the value of all future human lives. We review the challenges to studying human extinction risks and, by way of example, estimate the cost effectiveness of preventing extinction-level asteroid impacts.
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3. Estimating the Near-Term Probability of Extinction
It is possible for humanity (or its descendents) to survive a million years or more, but we could succumb to extinction as soon as this century. During the Cuban Missile Crisis, U.S. President Kennedy estimated the probability of a nuclear holocaust as “somewhere between one out of three and even” (Kennedy, 1969, p. 110). John von Neumann, as Chairman of the U.S. Air Force Strategic Missiles Evaluation Committee, predicted that it was “absolutely certain (1) that there would be a nuclear war; and (2) that everyone would die in it” (Leslie, 1996, p. 26).
More recent predictions of human extinction are little more optimistic. In their catalogs of extinction risks, Britain’s Astronomer Royal, Sir Martin Rees (2003), gives humanity 50-50 odds on surviving the 21st century; philosopher Nick Bostrom argues that it would be “misguided” to assume that the probability of extinction is less than 25%; and philosopher John Leslie (1996) assigns a 30% probability to extinction during the next five centuries. The “Stern Review” for the U.K. Treasury (2006) assumes that the probability of human extinction during the next century is 10%. And some explanations of the “Fermi Paradox” imply a high probability (close to100%)of extinction among technological civilizations (Pisani, 2006).4
I haven’t spent the time to look up the entire paper and read it, though I have followed this topic in the (popular) scientific news for most of my adult life. It is, in fact, one of the reasons why I decided to write Communion of Dreams – to explore the idea of humanity on the brink of extinction (as well as to examine Fermi’s Paradox, as I have written about previously). Just as most people seem to prefer ignoring their own mortality, we as a species seem to prefer ignoring the possibility of our own extinction. Even the vast majority of Science Fiction (including my own) written with humankind facing the possibility of extinction is resolved with some kind of salvation – it’d just be too bleak for most readers, otherwise.
And that doesn’t sell.
Jim Downey
Filed under: Astronomy, NASA, National Geographic, Science, Science Fiction, Space, Titan
I’m still playing catch-up, so just found this news item of interest on the National Geographic site – an excerpt:
But a new study reports faint signs of a natural electric field in Titan’s thick cloud cover that are similar to the energy radiated by lightning on Earth.
Lightning is thought to have sparked the chemical reactions that led to the origin of life on our planet.
“As of now, lightning activity has not been observed in Titan’s atmosphere,” said lead author Juan Antonio Morente of the University of Granada in Spain.
But, he said, the signals that have been detected “are an irrefutable proof for the existence of electric activity.”
OK, the piece is actually about how Titan is known to have all the necessary “prebiotic” conditions needed for the beginning of life as we know it, and how electrical activity from lightning on the moon could provide the spark to initiate life.
But I thought it a bit fun to speculate that the electric field detected is actually evidence of the tholin superconducting gel at the heart of Communion of Dreams.
Another travelogue from my recent trip later today, if things come together as I hope.
Jim Downey
Filed under: Astronomy, Bad Astronomy, Fireworks, NASA, Phil Plait, Science, Space
Via the Bad Astronomer, some really incredible images of our local star, courtesy of the Boston Globe:
The Sun is now in the quietest phase of its 11-year activity cycle, the solar minumum – in fact, it has been unusually quiet this year – with over 200 days so far with no observed sunspots. The solar wind has also dropped to its lowest levels in 50 years. Scientists are unsure of the significance of this unusual calm, but are continually monitoring our closest star with an array of telescopes and satellites. Seen below are some recent images of the Sun in more active times. (21 photos total)
Stunning stuff. Simply stunning.
Jim Downey
Filed under: Art, Astronomy, Bad Astronomy, Google, Heinlein, Heinlein Centennial, Jeff Greason, movies, Paleo-Future, Peter Diamandis, Phil Plait, Predictions, Robert A. Heinlein, Science, Science Fiction, Society, Space, Space X, tech, TGV Rockets, XCOR
Last night I watched a movie made before I was born. By coincidence, the timing was perfectly in sync with the news yesterday.
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Over a year ago, I wrote this, about Jeff Greason of XCOR Aerospace (one of the speakers at the Heinlein Centennial):
Yes, dependable reusable rockets is a critical first-step technology for getting into space. But as Greason says, he didn’t get interested in space because of chemical rockets – he got interested in chemical rockets because they could get him into space. For him, that has always been the goal, from the first time he read Rocket Ship Galileo by Robert Heinlein when he was about 10. It is somewhat interesting to note that similar to the setting and plot of the book, XCOR Aerospace is based on the edge of a military test range, using leased government buildings…
Anyway. Greason looked at the different possible technologies which might hold promise for getting us off this rock, and held a fascinating session at the Centennial discussing those exotic technologies. Simply, he came to the same conclusion many other very intelligent people have come to: that conventional chemical rockets are the best first stage tech. Sure, many other possible options are there, once the demand is in place to make it financially viable to exploit space on a large enough scale. But before you build an ‘interstate highway’, you need to have enough traffic to warrant it. As he said several times in the course of the weekend, “you don’t build a bridge to only meet the needs of those who are swimming the river…but you don’t build a bridge where no one is swimming the river, either.”
And this, in a piece about Pat Bahn of TGV Rockets:
And there was a lot of thought early in the development of rocketry that such capability could be used for postal delivery. It doesn’t sound economically feasible at this point, but there’s nothing to say that it might not become an attractive transportation option for such firms as UPS or FedEx if dependable services were provided by a TGV Rockets or some other company. In his juvenile novel Rocket Ship Galileo, Robert A. Heinlein had his characters adapt a retired “mail rocket” for their own spacecraft, used to fly to the Moon.
I find this notion of private development of spaceflight more than a little exciting. When I wrote Communion of Dreams, I was operating under the old model – that the enterprise of getting into space in a big way was going to mandate large governmental involvement and coordination. I’m not going to rewrite the novel, but I am reworking my own thoughts and expectations – this is probably the single largest change for me from attending the Centennial.
Well, yesterday a Falcon 1 rocket from the Space X corporation made it to orbit. From Phil Plait:
Congratulations to the team at Space X! At 16:26 Pacific time today (Sunday, September 28, 2008), their Falcon 1 rocket achieved orbit around the Earth, the first time a privately funded company has done such a feat with a liquid fuel rocket.
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As coincidence would have it, about the time the Space X rocket reached orbit I was watching Destination Moon, a movie I had added to my NetFlix queue after the Heinlein Centennial, and which just now had floated to the top.
What’s the big deal? Well, Destination Moon was about the first successful private corporation launch, not to orbit, but as a manned mission to the Moon.
It’s not a great movie. But it was fascinating to watch, an insight into those heady post-war years, into what people thought about space, and into the mind of Robert Heinlein, who was one of the writers and technical advisors on the film (with connections to two of his novels: Rocket Ship Galileo and The Man Who Sold the Moon). Interesting to see the trouble they went to in order to explain what things would be like in space (no gravity, vacuum, how rockets would work, et cetera) because this was a full 8 years prior to the launch of Sputnik. We’ve grown up with spaceflight as a fact, with knowing how things move and function – but all of this was unknown to the average viewer when the movie was made and released. They did a surprisingly good job. And the images provided Chesley Bonestell are still breath taking, after all these years.
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It may yet be a while before any private corporation wins the Google Lunar X Prize, let alone sends a team of astronauts there and gets them back, as was done in Destination Moon. But it’ll happen. When it looks like it will, I may need to schedule another viewing of the movie, and not just trust to coincidence.
Jim Downey
Filed under: Astronomy, Bad Astronomy, NASA, Phil Plait, Science, Science Fiction, Space
Play with your brain. Or, more accurately, let the universe play with it.
Jim Downey
An academic buddy of mine and I like to joke that this time of the year is called “Pass-over.” No, not Pesach – that happens in the spring. Rather, this is the time of year when the MacArthur Foundation announces their annual Fellows, the so-called ‘genius grants’ given each year to a group of particularly brilliant (though sometimes obscure) researchers, writers, academics, artists, and performers. This year 25 such Fellows were announced, and each will receive $500,000 over the next five years with no strings attached – in order to help facilitate whatever they do.
Man, who wouldn’t want to win that??? Nah, it’s not just the money and prestige – it’s the vote of confidence that they so believe in you that they’re willing to turn you loose with that sum of money, just to be creative.
And of course, we call it “Pass-over” because, well, we get passed-over for such each year. Like this year. Again.
Hey, I’m an artist! I’m a writer! I’m obscure! Depending on who you talk to (and how much I’ve paid them), I’m brilliant!
Ah, well. So it goes. Congrats to all the 2008 winners – go, and make the world a better place.
Jim Downey
Filed under: Artificial Intelligence, Astronomy, Humor, MetaFilter, Science, Space, tech
OK, I spent *way* too much time playing this game last night: Orbitrunner. And because I’m the kind of guy that I am, I wanted to inflict it on you.
It’s actually a very interesting bit of gaming, for as simple as seems at first glance. Here’s the description from the site:
Control the Sun with your mouse. Use it to manipulate the planets’ paths. The Sun’s pull gets stronger as planets get closer. If the gravity is at a right angle to the direction of travel, an orbit can form. Make sure planets don’t leave the screen or collide!
I’m sure that they have established some fairly basic approximations for your computer to manipulate, but it still addresses one of the classic problems of physics: how to calculate the orbital dynamics for two or more bodies in motion. Even if you restrict the interactions to one orbital plane, this is a surprisingly difficult problem for more than two bodies, and has been for centuries. From ScienceWorld:
The three-body problem considers three mutually interacting masses
,
, and
. In the restricted three-body problem,
The efforts of many famous mathematicians have been devoted to this difficult problem, including Euler
and Lagrange
And Wikipedia has a very good entry (beyond my math level) about the broader n-body problem:
General considerations: solving the n-body problem
In the physical literature about the n-body problem (n ≥ 3), sometimes reference is made to the impossibility of solving the n-body problem. However one has to be careful here, as this applies to the method of first integrals (compare the theorems by Abel and Galois about the impossibility of solving algebraic equations of degree five or higher by means of formulas only involving roots).
The n-body problem contains 6n variables, since each point particle is represented by three space (displacement) and three velocity components. First integrals (for ordinary differential equations) are functions that remain constant along any given solution of the system, the constant depending on the solution. In other words, integrals provide relations between the variables of the system, so each scalar integral would normally allow the reduction of the system’s dimension by one unit. Of course, this reduction can take place only if the integral is an algebraic function not very complicated with respect to its variables. If the integral is transcendent the reduction cannot be performed.
Well, have fun with it. And be amused about that all that phenomenal computing power at your fingertips making a simple little game. Such is the future.
Jim Downey
(Via MeFi. Cross posted to UTI.)
Communion Of Dreams 