Stories tagged Earth and Space Science

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 Cosmology@Home. Cosmology@Home 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
17
2007

Lake Superior: Photo by Mark Ryan
Lake Superior: Photo by Mark Ryan
Lake Superior is the greatest of the Great Lakes, and lately has become the subject of great concern. Superior’s water level has been dropping at an alarming rate in recent years, and is now at an all-time low. Lake Superior sets on the border of the United States and Canada, and people from both countries are trying to get answers. Some blame the drop in level on climate change, due to the decline of ice formation each winter on the lake and the subsequent increased evaporation. I covered this subject in an earlier posting that you can read about here. But others point to a chain reaction of water loss due to erosion and human activity farther down the Great Lakes System where the St. Clair River drains out of Lake Huron. Whatever the reasons, people on both sides of Superior are worried. The Canadian Broadcasting Corporation recently created a documentary titled Who Pulled the Plug on Lake Superior? which details the story. Watch it here.

MORE ABOUT SUPERIOR

Having grown up in Duluth, Minnesota on the western tip of Lake Superior, I continue to have a fascination with the great inland sea. The body of water is huge and powerful, and not to be taken lightly in inclement weather, when its mood can change in a matter of minutes. Waves during storms can reach up to 30 feet in height. The lake is the grave to more than 325 shipwrecks.

Here are some more quick facts about Lake Superior:

  • Elevation above sea level: 600 feet (183 m)
  • Maximum Length 350 miles (563 km)
  • Maximum Breadth: 160 miles (257 km)
  • Average Depth: 483 feet (147 m)
  • Maximum Depth 1333 feet (406 m)
  • Average Water Temperature: 40 degrees F.
  • It’s the largest freshwater lake in the world by surface area (31,820 square feet (2956 square meters))
  • It holds more than 2900 cubic miles of water (12,100 cubic km) which is enough to cover all of North and South America with a foot of water
  • The Anishiabe Ojibwe Indians called the lake “Gichigami”, which means “Big Water”.

A statistic I’ve always found interesting is that 3% of the water on Earth is fresh water, and 10% of that fresh water is held in Lake Superior. The total water in the four other Great Lakes match Superior’s volume, and together they equal the volume of water contained in Russia’s Lake Baikal, the largest freshwater lake by volume in the world.

Evidently, I’m not alone in this fascination with Lake Superior. Two conferences about the body of water are taking place in the next few weeks. The first is “Making a Great Lake Superior” (October 29-31, 2007), which will bring together scientists, tribal and government officials to present current research, education programs, and management ideas relating to the lake.

The second conference is the “Gales of November 2007” (November 2-3, 2007). It celebrates the maritime history of the lake, and will present exhibitors and speakers on regional history, shipwrecks, diving, and other lake-related subjects. This will be their 20th annual get-together.

Both conferences are being held at the Duluth Entertainment and Convention Center, in Duluth Minnesota.

Lastly, just for the heck of it, here’s a short video titled TWELVE MOONS ON GICHIGAMI that compresses a year of Lake Superior images into less than seven minutes.

LINKS

More about Lake Superior
“Making a Great Lake Superior” Conference
“Gales of November 2007” Conference

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.

Oct
10
2007

Industrial sites for sale?: According to some futurists, the moon could be the creation site and launching pad of missions to Mars. Robots would use materials found on the moon to make the spacecraft and then be able to blast off faster and cheaper from the moon's smaller gravitational pull. (Photo from NASA)
Industrial sites for sale?: According to some futurists, the moon could be the creation site and launching pad of missions to Mars. Robots would use materials found on the moon to make the spacecraft and then be able to blast off faster and cheaper from the moon's smaller gravitational pull. (Photo from NASA)
It looks like our moon could someday be rezoned for industrial use.

That’s what those involved in space exploration learned at a recent conference. For economic and efficiency reasons, robots would lead a team of manufacturers based on the moon building the spacecraft that would go to Mars.

Those attending the Space & Missile Defense Conference in Huntsville, Ala., learned that a Mars spaceship might be too large to build and launch from Earth. The ideal situation would be to have a team of robots based on the moon doing most of the work in building the craft.

Robots would be needed because the construction work would be too cumbersome for humans to do while wearing spacesuits. Researchers are also investigating ways to process moon soils into metals, such as aluminum, iron and titanium, which would then be used to build the spacecraft.

And due to the moon’s weaker gravitational pull, it will 20 times cheaper to launch Mars missions from the moon than from Earth.

While this all sounds pretty futuristic, aeronautic and space manufacturers are already designing and building the next generation of U.S. spacecrafts, the Ares I and Ares V, which will replace the current fleet of space shuttles. The Ares I will shuttle astronauts in and out of space. The larger Ares V will be used to transport heavier cargos.

What do you think about using the moon as a factory? Share your thoughts here with other Science Buzz readers.

Oct
07
2007

Gryposaurus monumentensis skull: Photo courtesy Utah Museum of Natural History
Gryposaurus monumentensis skull: Photo courtesy Utah Museum of Natural History
Scientists from Utah have described a new species of power-jawed duck-billed dinosaur in a recent issue of the Zoological Journal of the Linnean Society.

The new find, an unstoppable Mesozoic lawnmower named Gryposaurus monumentensis, was dug out of the mudstones and sandstones of the Kaiparowits Formation at the Grand Staircase-Escalante National Monument in southern Utah.

Artist rendering of Gryposaurus monumentensis: Illustration by Larry Felder
Artist rendering of Gryposaurus monumentensis: Illustration by Larry Felder
Gryposaurs were members of the dinosaur family known as Hadrosauridae, a common herbivore that lived about 75 million years ago near the end of the Cretaceous period, when the North American continent was divided in two by a large inland sea.

Four other members of the genus gryposaurus have been found prior to this, but what makes this new species different from the others is the structure of its jaw.

"The snout is very robust indeed - it is much larger and much stronger-looking than any other duck-billed dinosaur," said paleontologist Terry Gates of the Utah Museum of Natural History in Salt Lake City. "In addition, the angle of the snout is more vertical, which initially leads to a hypothesis that it had a stronger bite."

With such a powerful bite it’s no surprise to hear Gates’ UMNH colleague Scott Sampson refer to Gryposaurus monumentensis as “the Arnold Schwartzenegger of duck-billed dinosaurs.”

Grand Staircase-Escalante digsite: Workers extract Gryposaurus remains from the rock in southern Utah. Photo courtesy the Raymond M. Alf Museum of Paleontology
Grand Staircase-Escalante digsite: Workers extract Gryposaurus remains from the rock in southern Utah. Photo courtesy the Raymond M. Alf Museum of Paleontology
Remains of the new dinosaur were first discovered in 2002 by members of a dig team from Raymond M. Alf Museum of Paleontology the, based in California.

At first only the skull had been found. But soon after the lower jaw and other skeletal remains were located nearby. And the lower teeth matched perfectly with the upper skull.

With more than 300 teeth crammed into its beak and some 500 others waiting in reserve, Gryposaurus monumentensis appears to have been a giant 30-foot power mower, and must have caused the flora of the lush and humid Late Cretaceous period to quake in its roots.

"When you combine the 800 teeth with the very large, strong jaw and beak you have a very formidable plant eater," Gates said. Although the paleontologists discovered more than 20 new species of plants in the same rock unit, none of them would have probably been a match against the duck-bill’s tenacious choppers.

But the super-chomping Gryposaurus had its own worries. While it was busy decimating the Mesozoic botanicals, carnivores were busy eyeing him as their next meal.

“Here at the Utah Museum of Natural History we have examples of duck-billed dinosaur bones that have been eaten by a tyrannosaur,” Gates said.

INFO SOURCES

Story at BBC website
Story at Newscientist.com
Utah Museum of Natural History