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What happens when you wring a washcloth out in zero gravity? Something cool.
Commander Hadfield is the best. I love when he casually lets go of the wireless mic and it just floats there right in front of his face. (thx, dusty)
Great article by Burkhard Bilger about NASA’s Curiosity mission to Mars.
The search for life on Mars is now in its sixth decade. Forty spacecraft have been sent there, and not one has found a single fossil or living thing. The closer we look, the more hostile the planet seems: parched and frozen in every season, its atmosphere inert and murderously thin, its surface scoured by solar winds. By the time Earth took its first breath three billion years ago, geologists now believe, Mars had been suffocating for a billion years. The air had thinned and rivers evaporated; dust storms swept up and ice caps seized what was left of the water. The Great Desiccation Event, as it’s sometimes called, is even more of a mystery than the Great Oxygenation on Earth. We know only this: one planet lived and the other died. One turned green, the other red.
Perfect read if you’ve been curious about what Curiosity is up to on Mars but needed something a bit more narrative than the mission home page or Wikipedia page to guide you. Also features the phrase “a self-eating watermelon of despair”, so there’s that. Oh, and here’s the Seven Minutes of Terror video referred to in the story.
In the pages of Sidereus Nuncius, Galileo described the four large moons of Jupiter in a series of 64 sketches which looked a lot like ASCII art in the text:
Using an online tool for computing the positions of Jupiter’s moons, Ernie Wright compared Galileo’s sketches to the moons’ actual motions.
Click through for an animated GIF of all the comparisons. Not bad for the telescopic state of the art in 1610. For a taste of how celestial objects actually appeared when viewed through Galileo’s telescope, check out this video starting around 7:30. (thx, john)
It’s science fiction for now, but two companies are betting that mining asteroids for minerals will be possible in the near future.
The potential bonanza is, well, astronomical. A single 500-metre metal-rich asteroid might contain the equivalent of all the platinum-group metals mined to date. Icy bodies could provide water to sustain astronauts or be processed into rocket fuel for future missions to Mars.
Since the Sun moves relative to the other stars around it at about 45,000 miles/hr, if you change the frame of reference from the Sun to the surrounding stellar system, you get planetary motion that looks something like this:
I would take this video with a grain of salt though, especially when it says things like “the Sun is like a comet, dragging the planets in its wake”…the planets don’t lag behind the Sun. Better to think of the thing as a conceptual schematic: resembling reality but not really accurate. (via @pieratt)
Update: There’s a new version of the video that addresses some of the concerns raised about the first video:
(thx, john)
Update: Phil Plait from Bad Astronomy has posted a pretty thorough takedown of this video.
However, there’s a problem with it: It’s wrong. And not just superficially; it’s deeply wrong, based on a very wrong premise. While there are some useful visualizations in it, I caution people to take it with a galaxy-sized grain of salt.
So far, humans have taken photos from the surfaces of Earth, the Moon, Venus, and Mars. But I had no idea that a photo from the surface of Titan existed:
The photo of the Saturnian moon was taken in 2005 by the Huygens probe, which was designed to land safely on the moon’s surface. From Wikipedia:
After landing, Huygens photographed a dark plain covered in small rocks and pebbles, which are composed of water ice. The two rocks just below the middle of the image on the right are smaller than they may appear: the left-hand one is 15 centimeters across, and the one in the center is 4 centimeters across, at a distance of about 85 centimeters from Huygens. There is evidence of erosion at the base of the rocks, indicating possible fluvial activity. The surface is darker than originally expected, consisting of a mixture of water and hydrocarbon ice. The assumption is that the “soil” visible in the images is precipitation from the hydrocarbon haze above.
And a special close-but-no-cigar award goes to the NEAR Shoemaker probe, which snapped this photo from about 400 feet above the surface of the near-Earth asteroid Eros:
The probe landed on the surface of Eros in February 2001 and transmitted usable data for about two weeks afterwards, none of which was photographic in nature.
It would look something like this:
That’s from a series called Darkened Skies by Thierry Cohen; he photographed various cities (NYC, Paris, Tokyo, SF) and matched them up with starry skies from more remote places like Montana, Nevada, and the Sahara. New Yorkers can see Cohen’s work at the Danziger Gallery starting March 28.
See also Imagining Earth with Saturn’s Rings.
Another fine installment of XKCD’s What If? series: What would happen if you tried to fly a normal Earth airplane above different Solar System bodies?
Unfortunately, [the X-Plane simulator] is not capable of simulating the hellish environment near the surface of Venus. But physics calculations give us an idea of what flight there would be like. The upshot is: Your plane would fly pretty well, except it would be on fire the whole time, and then it would stop flying, and then stop being a plane.
(via stellar)
The Space Shuttle Challenger disintegrated shortly after liftoff 27 years ago today. Physicist Richard Feynman had a hand in determining the reason for the disaster.
I’m an explorer, ok? I get curious about everything and I want to investigate all kinds of stuff.
Here’s Feynman’s appendix to The Presidential Commission on the Space Shuttle Challenger Accident in which he dissents with the majority opinion of the commission. His conclusion:
If a reasonable launch schedule is to be maintained, engineering often cannot be done fast enough to keep up with the expectations of originally conservative certification criteria designed to guarantee a very safe vehicle. In these situations, subtly, and often with apparently logical arguments, the criteria are altered so that flights may still be certified in time. They therefore fly in a relatively unsafe condition, with a chance of failure of the order of a percent (it is difficult to be more accurate).
Official management, on the other hand, claims to believe the probability of failure is a thousand times less. One reason for this may be an attempt to assure the government of NASA perfection and success in order to ensure the supply of funds. The other may be that they sincerely believed it to be true, demonstrating an almost incredible lack of communication between themselves and their working engineers.
In any event this has had very unfortunate consequences, the most serious of which is to encourage ordinary citizens to fly in such a dangerous machine, as if it had attained the safety of an ordinary airliner. The astronauts, like test pilots, should know their risks, and we honor them for their courage. Who can doubt that McAuliffe was equally a person of great courage, who was closer to an awareness of the true risk than NASA management would have us believe?
Let us make recommendations to ensure that NASA officials deal in a world of reality in understanding technological weaknesses and imperfections well enough to be actively trying to eliminate them. They must live in reality in comparing the costs and utility of the Shuttle to other methods of entering space. And they must be realistic in making contracts, in estimating costs, and the difficulty of the projects. Only realistic flight schedules should be proposed, schedules that have a reasonable chance of being met. If in this way the government would not support them, then so be it. NASA owes it to the citizens from whom it asks support to be frank, honest, and informative, so that these citizens can make the wisest decisions for the use of their limited resources.
For a successful technology, reality must take precedence over public relations, for nature cannot be fooled.
Clear thought, clear writing. Feynman was perhaps the most efficient mechanism ever conceived for consuming complexity and pumping out simplicity. (via @ptak)
At a training site in Arizona called Cinder Lake, NASA created a “simulated lunar environment” for the purpose of testing lunar rovers and other pieces of equipment.
At the end of a four-day period of controlled explosions, USGS scientists had succeeded in creating a 500 square foot “simulated lunar environment” in Northern Arizona — forty-seven craters of between five and forty feet in diameter designed to duplicate at a 1:1 scale a specific location (and future Apollo 11 landing site) on the moon, in a region called the Mare Tranquillitatis.
If they faked the Moon landing, this is probably where they did it.
I had no idea there was footage shot on the Moon from the perspective of a lunar rover passenger…basically a lunar rover dash cam. It’s the second half of this short video. Amazing. The first part shows the rover speeding off (at about 6 miles/hr), being put through its paces. From the transcript of the “Grand Prix”:
124:58:52 Duke: The suspension system on that thing is fantastic!
124:58:54 England: That sounds good. We sound like we probably got enough of the Grand Prix. We’re willing to let you go on from here. Call that a (complete) Grand Prix.
124:59:03 Duke: Okay. (Pause) Man, that was all four wheels off the ground, there. Okay. Max stop.
124:59:12 Young: Okay. I don’t want to do that.
124:59:13 Duke: Okay. Excuse me.
124:59:16 Young: They say that’s a no-no.
124:59:22 Duke: Okay, DAC off; Mark. Okay, John. DAC’s off.
124:59:27 Young: Okay. I have a lot of confidence in the stability of this contraption.
124:59:30 Duke: Me, too.
124:59:32 England: Sounds great.
Also, we took a fucking car to the Moon! Three times!
Filmmaker S.G. Collins argues that in 1969, it was easier to send people to the Moon than to fake the landing in a studio. Technologically speaking, it was impossible to shoot that video anywhere other than the surface of the Moon. Which sounds crazy.
(via devour)
NASA is testing something they call SPHERES (Synchronized Position Hold, Engage, Reorient, Experimental Satellites) on the International Space Station…they are spherical robots that can fly around the station and perform simple tasks. They were inspired by the floating droid remote that Luke trains with in Star Wars. The most recent test was in December.
The Smart SPHERES, located in the Kibo laboratory module, were remotely operated from the International Space Station’s Mission Control Center at Johnson to demonstrate how a free-flying robot can perform surveys for environmental monitoring, inspection and other routine housekeeping tasks.
In the future, small robots could regularly perform routine maintenance tasks allowing astronauts to spend more time working on science experiments. In the long run, free-flying robots like Smart SPHERES also could be used to inspect the exterior of the space station or future deep-space vehicles.
They are outfitting the Smart SPHERES with Android phones for data collection:
Each SPHERE Satellite is self-contained with power, propulsion, computing and navigation equipment. When Miller’s team first designed the SPHERES, all of their potential uses couldn’t be imagined up front. So, the team built an “expansion port” into each satellite where additional sensors and appendages, such as cameras and wireless power transfer systems, could be added. This is how the Nexus S handset — the SPHERES’ first smartphone upgrade — is going to be attached.
“Because the SPHERES were originally designed for a different purpose, they need some upgrades to become remotely operated robots,” said DW Wheeler, lead engineer in the Intelligent Robotics Group at Ames. “By connecting a smartphone, we can immediately make SPHERES more intelligent. With the smartphone, the SPHERES will have a built-in camera to take pictures and video, sensors to help conduct inspections, a powerful computing unit to make calculations, and a Wi-Fi connection that we will use to transfer data in real-time to the space station and mission control.”
Here’s some video from a past test:
NASA astronaut Sunita Williams, who has spent almost a year in space, gives us a 25-minute tour of the International Space Station. AKA the nerdiest episode of MTV Cribs.
(via @durietz)
The timeline of the far future artice is far from the longest page on Wikipedia, but it might take you several hours to get through because it contains so many enticing detours. What’s Pangaea Ultima? Oooh, Roche limit! The Degenerate Era, Poincaré recurrence time, the Big Rip scenario, the cosmic light horizon, the list goes on and on. And the article itself is a trove of fascinating facts and eye-popping phrases. Here are a few of my favorites. (Keep in mind that the universe is only 13.75 billion years old. Unless we’re living in a computer simulation.)
50,000 years: “Niagara Falls erodes away the remaining 32 km to Lake Erie and ceases to exist.”
1 million years: “Highest estimated time until the red supergiant star Betelgeuse explodes in a supernova. The explosion is expected to be easily visible in daylight.”
1.4 million years: “The star Gliese 710 passes as close as 1.1 light years to the Sun before moving away. This may gravitationally perturb members of the Oort cloud; a halo of icy bodies orbiting at the edge of the Solar System. As a consequence, the likelihood of a cometary impact in the inner Solar System will increase.”
230 million years: “Beyond this time, the orbits of the planets become impossible to predict.”
800 million years: “Carbon dioxide levels fall to the point at which C4 photosynthesis is no longer possible. Multicellular life dies out.”
4 billion years: “Median point by which the Andromeda Galaxy will have collided with the Milky Way, which will thereafter merge to form a galaxy dubbed ‘Milkomeda’.”
7.9 billion years: “The Sun reaches the tip of the red giant branch, achieving its maximum radius of 256 times the present day value. In the process, Mercury, Venus and possibly Earth are destroyed. During these times, it is possible that Saturn’s moon Titan could achieve surface temperatures necessary to support life.”
100 billion years: “The Universe’s expansion causes all galaxies beyond the Milky Way’s Local Group to disappear beyond the cosmic light horizon, removing them from the observable universe.”
1 trillion years: “The universe’s expansion, assuming a constant dark energy density, multiplies the wavelength of the cosmic microwave background by 10^29, exceeding the scale of the cosmic light horizon and rendering its evidence of the Big Bang undetectable.”
1 quadrillion years: “Estimated time until stellar close encounters detach all planets in the Solar System from their orbits. By this point, the Sun will have cooled to five degrees above absolute zero.”
10^65 years: “Assuming that protons do not decay, estimated time for rigid objects like rocks to rearrange their atoms and molecules via quantum tunneling. On this timescale all matter is liquid.”
10^10^56 years: “Estimated time for random quantum fluctuations to generate a new Big Bang, according to Caroll and Chen.”
Read the whole thing, it’s worth the effort. (via @daveg)
Note: Illustration by Chris Piascik…prints & more are available.
This impressive 7,000 word essay written by user Memphet’ran on the appropriately named Spacebattles.com forum attempts to answer that question.
There are only a handful of engines that allow a combination of high thrust and low mass ratio. The most promising are Orion nuclear pulse propulsion and the nuclear salt water rocket. Some nuclear thermal designs also have thrust high enough to possibly be useful, although only for a small ship. The user “RJP” on Spacebattles also suggested something called a fission fragment drive which works by throwing high-velocity fuel fragments out the back of the ship, but other sites I’ve researched suggest it would be a low-thrust high-ISP [in-space propulsion] system more suitable to an explorer than a warship. Orion works by the (seemingly insane, but actually quite effective) method of throwing nuclear bombs behind the spacecraft and having it ride the blasts. The hot gasses from the detonations hit a heavy pusher plate at the back of the ship and drive it forward. NSWR [nuclear salt water rocket] is similar, but it instead uses a solution of fissionables in salt water that spontaneously explodes as it leaves the rocket nozzle. Both systems cleverly shift the propulsive reaction outside the spacecraft, eliminating the need to deal with most of the heat it produces and allowing it to be made much more energetic.
For the same reason that we have Space Shuttle launch delays, we’ll be able to tell exactly what trajectories our enemies could take between planets: the launch window. At any given point in time, there are only so many routes from here to Mars that will leave our imperialist forces enough fuel and energy to put down the colonists’ revolt.
If you’ve got a hankering to go hands on, the video games EVE and FTL approach realistic space battles in their own ways.
(via @BenKuckera)
A European team of exoplanet hunters has discovered a planet about the size of Earth orbiting Alpha Centauri B, which is in a group of stars closest to the solar system, a mere 4.3 light years away. Lee Billings explains the significance.
At a distance of just over 4.3 light years, the stars of Alpha Centauri are only a cosmic stone’s throw away. To reach Alpha Centauri B b, as this new world is called, would require a journey of some 25 trillion miles. For comparison, the next-nearest known exoplanet is a gas giant orbiting the orange star Epsilon Eridani, more than twice as far away. But don’t pack your bags quite yet. With a probable surface temperature well above a thousand degrees Fahrenheit, Alpha Centauri B b is no Goldilocks world. Still, its presence is promising: Planets tend to come in packs, and some theorists had believed no planets at all could form in multi-star systems like Alpha Centauri, which are more common than singleton suns throughout our galaxy. It seems increasingly likely that small planets exist around most if not all stars, near and far alike, and that Alpha Centauri B may possess additional worlds further out in clement, habitable orbits, tantalizingly within reach.
On Saturday, the Space Shuttle Endeavour was driven 12 miles through the streets of Los Angeles on its way to the California Science Center. It was a tight fit at times.
While driving a couple weeks ago, I happened to catch a meteor shooting across the sky:
Saw one of the coolest things ever tonight: a meteor burning up in the lower atmosphere. Super bright, exploded at the end like a firework.
It turned out that “one of the coolest things ever” wasn’t hyperbole. You see, earlier that day over the UK, a meteor streaked across the sky for about 50 seconds:
And then the one I saw happened about two-and-a-half hours later. Spurred by this unlikely coincidence, mathematician Esko Lyytinen of the colorfully named Finnish Fireball Working Group of the Ursa Astronomical Association did some calculations and determined that the two events were actually the same meteor.
He believes a large body grazed the upper atmosphere, dipping to an altitude of 33 miles (53 km) over Ireland before escaping back to space. Because it arrived moving at only about 8 miles (13 km) per second, barely above Earth’s escape velocity, it lingered for more than a minute as it crossed the sky. (This explains why some witnesses mistook it for reentering spacecraft debris.)
Lyytinen says the brief atmospheric passage took its toll. As the meteoroid broke apart, its velocity dropped to just 5.7 miles (9.2 km) per second, too slow to make an escape back to space. Instead, it became a temporary satellite of Earth, looping completely around the globe before reentering the atmosphere — this time for good. “It looks now that the fireball witnessed 155 minutes later in U.S. and Canada, may have been one fragment of the British fireball, most probably the biggest one,” Lyytinen explains.
These earth-grazers are not common but they do happen from time to time. But a visible Earth grazing meteor that enters the atmosphere twice? Unprecedented. So cool! (thx, alex)
Earlier this month, the Curiosity rover photographed a dry stream bed on the surface of Mars.
That’s the Mars river bed on the left and an Earth river bed on the right. Note the flat smooth rocks in the Mars pic. Pretty cool.
It turns out that yo-yos work pretty well in space. Astronaut Don Pettit demontrates from the International Space Station.
(via explore)
From Our City, Our Story, the story of a Rockford, Illinois gear factory that made all of the gears for the Mars Curiosity rover.
What might be more remarkable than creating crucial equipment destined for Mars? For a second time? Well, creating a thriving motivated company culture with a team of career employees — the kind who lie in bed at night thinking, “what can I do in the morning when I get there?” The kind who take on responsibility, impose their own high standards and like Amy Sovina, have the “mindset something I touched is now on the surface of Mars.”
I would love to have seen a live feed of these gear shop employees watching the landing.
Neil Armstrong, the first man to walk on the Moon, died today at the age of 82.
Although he had been a Navy fighter pilot, a test pilot for NASA’s forerunner and an astronaut, Mr. Armstrong never allowed himself to be caught up in the celebrity and glamour of the space program.
“I am, and ever will be, a white socks, pocket protector, nerdy engineer,” he said in February 2000 in one a rare public appearance. “And I take a substantial amount of pride in the accomplishments of my profession.”
A sad day; Armstrong was one of my few heroes. In my eyes, Armstrong safely guiding the LEM to the surface of the Moon, at times by the seat of his pants, is among the most impressive and important things ever done by a human being.
There’s nothing like a composite photo of the Perseids meteor shower to hammer home the realization that the Earth is hurtling through space like the Millennium Falcon making the Kessel Run. Photo by David Kingham.
The main imaging cameras on the Mars Curiosity rover have only 2-megapixel sensors with 8 GB of flash memory — compare that to a maxed-out iPhone 4S with an 8-megapixel sensor and 64 GB of flash memory (not to mention 30-fps 1080p video). Planning timeframes and communications bandwidth contributed to the chosen camera size.
‘There’s a popular belief that projects like this are going to be very advanced but there are things that mitigate against that. These designs were proposed in 2004, and you don’t get to propose one specification and then go off and develop something else. 2MP with 8GB of flash [memory] didn’t sound too bad in 2004. But it doesn’t compare well to what you get in an iPhone today.’
The cameras were also supposed to be outfitted with zoom lenses but that part of the project was scrapped.
On Twitter right now, Neil deGrasse Tyson is imagining how various Olympic events would work on Mars.
Women’s Beach Volleyball on Mars: No protective ozone layer there. Solar UV would irradiate all exposed legs, buns, & tummies
Gymnastics: On Mars, with only 38% of Earth’s gravity, the Vault & other spring-assisted leaps would resemble circus cannons.
(via @jaycer17)
What if Mars orbited the Earth at the same distance as the Moon…what would that look like? How about Neptune? Or Jupiter? Like this:
See also what the Earth would look like with Saturn’s rings. (via @stevenstrogatz)
The rest of you can have your Olympics, but the early August event I’m most looking forward to is the arrival on Mars of the Curiosity rover. But NASA has had some problems in the past delivering payloads to Mars, so this is going to be somewhat of a nail-biter. If you haven’t seen it, Curiosity’s Seven Minutes of Terror is well worth watching to see the logistical challenge of getting the rover down to the surface.
Curiosity will hopefully land on the surface on Aug 6 at about 1:30 am ET.
The Apollo 11 Lunar Module landed on the surface of the Moon 43 years ago today. For the 40th anniversary of the landing in 2009, I put together a page where you can watch the original CBS News coverage of Walter Cronkite reporting on the Moon landing and the first Moon walk, synced to the present-day time. I’ve updated the page to work again this year: just open this page in your browser and the coverage will start playing at the proper time. Here’s the schedule:
Moon landing broacast start: 4:10:30 pm EDT on July 20
Moon landing shown: 4:17:40 pm EDT
Moon landing broadcast end: 4:20:15 pm EDT
{break}
Moon walk broadcast start: 10:51:27 pm EDT
First step on Moon: 10:56:15 pm EDT
Nixon speaks to the Eagle crew: approx 11:51:30 pm EDT
Moon walk broadcast end: 12:00:30 pm EDT on July 21
Here’s a post I wrote when I launched the project.
If you’ve never seen this coverage, I urge you to watch at least the landing segment (~10 min.) and the first 10-20 minutes of the Moon walk. I hope that with the old time TV display and poor YouTube quality, you get a small sense of how someone 40 years ago might have experienced it. I’ve watched the whole thing a couple of times while putting this together and I’m struck by two things: 1) how it’s almost more amazing that hundreds of millions of people watched the first Moon walk *live* on TV than it is that they got to the Moon in the first place, and 2) that pretty much the sole purpose of the Apollo 11 Moon walk was to photograph it and broadcast it live back to Earth.
Thanks to Dave Schumaker for the reminder.
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