Stories tagged Earth and Space Science

Nov
30
2007

Where's the lightning?: I can't see any lightning in this picture, but recent magnetic antenna data shows that Venus has regular lightning flashes in its dense atmosphere.
Where's the lightning?: I can't see any lightning in this picture, but recent magnetic antenna data shows that Venus has regular lightning flashes in its dense atmosphere.Courtesy NASA
With a name like Thor, any mention of lightning and thunder jumps off the page (or computer screen) demanding my immediate attention.

So I was locked into yesterday’s account that the European Space Agency’s Venus Express has confirmed the theories astronomers have had for years, that lightning strikes on Venus.

Lightning is one of the factors considered in the evoluntionary process that could have “sparked” life into inorganic materials. But weather and climate conditions on Venus today suggest that the window of supporting life forms has been long shut on the planet.

But the finding of lightning has electrified the weather forecasts for Earth’s solar system neighbor. Previously, astronomical meteorologists had figured that Venus had a long, boring forecast of strong, steady winds for the next 400 years.

Venus Express, which has been orbiting Venus for nearly two years now, used a magnetic antenna to pick up the planet’s lightning activities.

So if you had a strong enough telescope to see a lightning flash on Venus, how long would you have to count until you hear the ensuing thunder clap? Talk amongst yourselves to come up with the answer.

Nov
27
2007

Mars Rovers
Mars RoversCourtesy NASA/JPL-Caltech
About this time last year it was springtime on Mars. The two rovers had survived winter but a large, planet wide dust storm threatened to deplete their source of energy. To survive, both rovers were put into survival mode for several months. The both came through OK but because their solar panels are coated with dust, they do not have the energy they used to. Another winter is now approaching so both Rovers need to find a spot to maximize their solar gain.

Preparing for a long Mars winter

Spirit spent last winter on the sunny side of a hill called "Winter Haven" (click to see panorama) This winter Spirit is heading north toward an extra steep slope on "Home Plate". Right now it is stuck in what appears to be loose soil.

Rovers are showing their age

Spirit is having trouble getting around because one of its wheels doesn't work. It needs to go backwards, dragging its bad front wheel. Opportunity has a wheel that cannot steer. Its instrument arm is arthritic due to a bad motor in its shoulder. Opportunity is also blind in its infrared "eye" because of too much dirt on its lens. Both rovers are having problems with their grinding tools (RAT).

Mars rover's mission extended again

The twin rovers landed on the surface of Mars in January, 2004. Mission planners expected that it would only take a few months before dust coated the rovers' solar panels so thickly that they wouldn't be able to generate power any more. But the Martian weather had a trick; dust devils and wind gusts came by often enough to keep the solar panels relatively clear of dust. Without the loss of power looming, the rovers have been able to keep going, and going, and going. UniverseToday

Catch up on news about the Mars Rovers

Nov
25
2007

This is how the moon feels: all the time now.
This is how the moon feels: all the time now.Courtesy Wikimedia commons
The product of a brief and fateful union between the earth and “a body as big as Mars” in the back alley of the solar system, our moon has never quite come to grips with its lack of a present father figure With a distant mother and no siblings, the Moon has no true peers to turn to, and has always had to reassure itself that, someday, definitely someday, it would find a moon just like it, a friend and comrade that it could finally relate to.

Unfortunately, the social workers of the galaxy, astronomers, have recently had to bear the bleak news to the Moon that it is, at best, an ”uncommon moon”, and that the chances of it ever finding its soul mate are “pretty sucky.”

Most moons were either formed simultaneously to the formation of their planets, or were trapped by a planet’s gravity at some point. Our moon was probably created thirty to fifty million years after the formation of the solar system by a massive impact between Earth and a Mars-sized body (the impact would have tossed enough material into “circumterrestrial orbit” to form the Moon). These sort of moon-creating knock-ups, if you will, leave a cloud of telltale dust in a star system, allowing scientists a general idea of which moons were created that way. By examining how many star systems have this dust could, astronomers have determined that it is likely that only 5 to 10 percent of moons (at most) share a similar origin to ours.

This was an understandably crushing revelation for the Moon. It remains in a gray mood, despite the consolations of people around the world, many of who have insisted that it is “still pretty.”

Nov
15
2007

Rosetta: It didn't want to cause any trouble. All it wants to do is chase comets.
Rosetta: It didn't want to cause any trouble. All it wants to do is chase comets.Courtesy Wikimedia commons
Just in case you were concerned, the planet earth isn’t about to get creamed by an asteroid.

Oh? You weren’t concerned? Never mind.

Apparently, last week the Minor Planet Center was just about to release an emergency warning that a large, extra-terrestrial body was just about to pass a hair’s breadth from the earth – it should have skimmed by about 3,500 miles away. That’s creepily close, when we’re dealing with space.

Fortunately (for our stress centers, I guess) a clever Russian scientist actually took the time to look at the nearly earth-bound mass, and to track its trajectory, and realized that it was, in fact, the European, comet-chasing probe, Rosetta. Rosetta is about the size of a utility van (with wings), and we are quite safe from it.

So, thanks to one plucky Russian astronomer, the world is safe again. You all still have a pretty good chance of getting hit by cars tomorrow, though, or by dead birds falling from the sky. Or of choking on something you thought would be harmless, like pudding.

Nov
12
2007

Planet Waterslide: A digital reconstruction of "the most fun planet."
Planet Waterslide: A digital reconstruction of "the most fun planet."Courtesy **Mary**
There was a brief period in the history of the solar system about 3.9 billion years ago characterized by wayward space particles pelting the inner planets. The period is referred to as the Late Heavy Bombardment, and the moon still bears the crater scars of the repeated impacts (Earth was similarly battered, but the constant recycling of the crust has erased the craters).

The prevailing theory behind the LHB has long been that early reshuffling of the planets was responsible – specifically that a rebellious young Neptune moved further out from the sun (perhaps seeking a place of its own) and disturbed rocky bodies in the Kuiper Belt, causing them to “veer into the inner solar system.”

Recently, an astrophysicist at the Carnegie Institution in Washington DC has provided compelling evidence that a migrating Neptune may not have been the cause after all. He thinks that the impact craters on the moon more closely match asteroids from the Asteroid Belt just beyond Mars, and that these asteroids were sent there by a disturbed orbit of a fifth rocky planet (the other rocky planets being, of course, Mercury, Venus, Earth, and Mars).

The planet, dubbed Planet V, would probably have been bigger than the moon, but slightly smaller than Mars. The Carnegie scientist even developed a computer model detailing how Mars’ gravity could have upset V’s orbit, causing it to fall into the sun, passing through the Asteroid Belt and scattering asteroids on its way.

The theory obviously requires extensive testing before it can be accepted with any confidence, but, so far, it has passed the test of whether or not I like it. I do like it.

I’m not terribly attached to the name, though. “V” is okay, I supposed, but it’s been done. I was thinking that something along the lines of “Planet Waterslide” would be better, not only because it sounds fun, but because it more accurately describes the character of the planet as suggested by my own theories. See, I predict that further research will reveal that “V” was covered in waterslides, and inhabited solely by kittens and friendly dinosaurs (neither of whom, ironically, ever used the waterslides). Planet Waterslide was the destiny of mankind, the universe’s reward for our inevitable achievement of interplanetary travel. Unfortunately, jealous Mars, not as brave as his big brother Neptune, and who never moved out of the parents’ basement of the solar system, tricked, or possibly tripped, its little brother Waterslide.

From this point, the Carnegie theory pretty much takes over. Except that the asteroid craters on the moon, should they receive further study, will no doubt prove to be interspersed with much smaller, fluffier craters.

Nov
08
2007

Al & the Earth: I wonder if Al Gore runs a distributed computing program on his Mac when he gives his global warming talks.  Probably not.  Image courtesy alexdecarvalho via Creative Commons/Flickr.
Al & the Earth: I wonder if Al Gore runs a distributed computing program on his Mac when he gives his global warming talks. Probably not. Image courtesy alexdecarvalho via Creative Commons/Flickr.
If you like science and you listen to podcasts I recommend Scientific American’s 60 Second Science. I don’t listen to them every day, but I store them up then listen to a bunch in a row while I am doing something menial. Today I listened to a bunch walking from my cube to the loading dock. It is a looooog walk.

Besides mentioning the giant Mars hoax emails, which I guess are circulating again with new dates, there were two stories caught my interest.

The first was about distributed computing. While I am an advocate for turning off computers at night to save energy, if you’re going to leave them on, you should put them to good use. They can either run scans on themselves, or, through distributed computing, they can use their processing power to solve large problems. One new distributed computing application that they mentioned that I found interesting is [email protected]. [email protected] uses your computer’s spare processing power to “search for the model that best describes our Universe and to find the range of models that agree with the available astronomical and particle physics data” (from their website). Since I can barely wrap my mind around the implications of that question I am glad that my computer can help find some answers.

Another interesting podcast was about global warming. Researchers from the University of Washington have been working on equations that will help get the most out of climate models. The result of their work is that while the Earth is going to get warmer, how much warmer is not known. Scientists have theorized that if the amount of carbon dioxide (CO2)in the atmosphere doubles the temperature would rise by about 2.2 degrees Fahrenheit. But, that rise in temperature does not account for the sort of “compound interest” that would take place – if the Earth warmed up because of more CO2, would the warmer atmosphere hold more water vapor? Would that increased amount of water vapor, serving as a “greenhouse gas” create even warmer temperatures? And what effect would these even warmer temperatures have on the climate models? This new equation helps scientists see the most probable scenarios more quickly than before, but also shows possible warmer results than previous models. The problem is that all this “compounding interest” makes it impossible to determine with any accuracy the high end possibilities. More on this can be found here, here and here.

Nov
05
2007

Attention seeking comet: Comet Holmes photographed in 6" reflector telescope, 100x, 2 seconds, 400iso on Oct 25,2007, 7:10 UT (from Minneapolis, Minnesota)  Image courtesy Tom Ruen via Wikipedia.
Attention seeking comet: Comet Holmes photographed in 6" reflector telescope, 100x, 2 seconds, 400iso on Oct 25,2007, 7:10 UT (from Minneapolis, Minnesota) Image courtesy Tom Ruen via Wikipedia.
So, in the category of “we don’t know why this is happening but you should check it out” a comet that used to be so dim you needed a telescope to see it has become suddenly so much brighter it can now be seen with the naked eye.

Comet 17P Holmes, visible to northern hemisphere residents, is practically demanding attention by suddenly becoming just over half a million times brighter than it was just a few hours previously. The comet can be found in the constellation Perseus and is visible for most of the night, and thanks to daylight savings time is easier to see earlier in the day. It resembles a fuzzy, yellowish star.

The comet was originally discovered by British astronomer Edwin Holmes on November 6, 1892. The crazy thing is, he discovered it because of a similar incident to what is happening now, it suddenly became so much brighter it was easily observable. Practically 115 years to the day! Also crazy is that if you think about its size (no more than 2 miles in diameter) and its distance from the Earth, it has to really be glowing to be seen!

In 1892 the comet faded after a few weeks, and we should expect a similar fading to happen in this instance – so get out there now to see this once in a lifetime opportunity! (Binoculars will help.)

Oct
30
2007

Million dollar prize unclaimed

Space elevator: Artist Pat Rawling's concept of a space elevator viewed from the geostationary transfer station looking down along the length of the elevator toward Earth.
Space elevator: Artist Pat Rawling's concept of a space elevator viewed from the geostationary transfer station looking down along the length of the elevator toward Earth.
The concept of building an elevator to carry materials up to space orbit was proposed by Arthur C. Clarke in his 1987 science fiction novel, 2061: Odyssey Three. Spaceward Foundation, which partnered with NASA holds two space-elevator-related competitions - the Tether Challenge and the Beam Power Challenge.

Tether Challenge

The tether competition is a perpetual dare for any group to present a tether that is at least 50% better than last year's best offering. Tethers are ranked according to strength and weight.

The strength of a material is measured in Giga-Pascals (GPa) and its weight, or more precisely, its density, is measured in grams per cubic centimeter {g/cc). In order to build the Space Elevator, we need a material that has a specific strength of 80-100 GPa-cc/g. elevator2010.org

The best entry in 2005 tether competition, using spectra 2000 fiber (Honeywell) had specific strength of 2.8. The best entry in 2006 tether competition, using Zylon fiber (Toyobo Inc.) had a specific strength of 3. This year's $500,000 offered to any team that could produce a tether with a specific strength of 4.5 went unclaimed.

Beam Power Challenge

The Beam Challenge tests the climbing ability and weight-bearing capability of robots scaling a cable.

The climbers net weight is limited to between 10 and 25 kg [22 - 55 lbs], and they must ascend the ribbon at a minimum of 2 m/s. [6.6 feet per second] Climbers will be rated according to their speed multiplied by the amount of payload they carried, and divided by their net weight. For example, a 15 kg climber, carrying 5 kgs of payload at 2.5 m/s will have a score of 5 · 2.5 · / 15 = 0.83

Climbers have to scale the ribbon while carrying some amount of payload, using only power that was transferred from the ground using beamed power. Power is unlimited. Some teams used mirrors and sunlight instead of laser beams. They were big trouble on cloudy days, though. The University of Saskatchewan Design for Space (USST) team came in first but missed the big money prize by a few seconds. Click here to see a video of the USST climber attempt.

Recommended Space Elevator links:

Oct
18
2007

Join us tonight for the Pompeii Adult Lecture: The Final Hours.

The Final Hours
Dr. Connie Rodriguez
Associate Professor and Department Chair of Classical Studies at Loyola of New Orleans
Thursday, October 18, 2007
7:00-9:00 PM

Dr. Rodriguez, visiting curator of the A Day in Pompeii exhibit, presents the final hours of Pompeii as related in letters by Pliny the Younger, who watched events unfold from a safe distance at Misenum. He tells of his uncle, Pliny the Elder, who was in charge of the Roman fleet stationed on the Bay of Naples and who met his death during the eruption of Mt. Vesuvius.

Tickets for each Pompeii lecture are $12 per person ($8 per Science Museum member). Lectures will take place from 7 to 9 p.m. in the Science Museum's auditorium on level 3. For more information or to reserve tickets, call (651) 221-9444.

Oct
16
2007

Ten year birthday for Cassini Huygens

Cassini-Huygens
Cassini-Huygens
The Cassini Huygens mission to Saturn just passed its ten year mark. It blasted off from Earth on Oct 15, 1997. I hooked up my computer to the internet a month later, and have been enjoying photos from it ever since. Last year for Paul McCartney's 64th birthday, sixty-four images from Cassini were put together into a poster and a movie.

Jupiter, Saturn, and its moons

Cassini flew by Jupiter on the way to Saturn . Cassini approached Saturn in mid-2004. One of my favorite photos is titled, The Dragon Storm. You can click through all of the Cassini photos by starting on this Cassini Imaging Diary page.

Huygens lands on Titan

The term "Huygens" refers to a probe attached to the Cassini craft. On Christmas Day, 2004 it separated itself and landed on Saturn's moon, Titan (click here to access videos and photos).

Learn more about Cassini-Huygens

If you haven't been following this exciting mission, you have ten years of catching up available.