Stories tagged Earth and Space Science
Lake Superior: Photo by Mark RyanLake 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
Tags : Ten year birthday for Cassini Huygens
Cassini-HuygensThe 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.
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.
Gryposaurus monumentensis skull: Photo courtesy Utah Museum of Natural HistoryScientists 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 FelderGryposaurs 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 PaleontologyRemains 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
Another race to the moon
Chang'e 1: China lunar probeUnited States, India, China, and Japan have each announced high-profile plans to send humans back to the moon for the first time since Apollo 17 landed there in 1972.
United States on moon by 2020
NASA has a 2020 deadline for returning Americans to the moon. China would like to beat that. At a recent meeting, NASA administrator Michael Griffin said,
"I personally believe that China will be back on the moon before we are,''
China's ambitious space program
Luo Ge, Vice Administrator, China National Space Administration, at the 22nd National Space Symposium (NSS) outlined China's agenda in space.
Generally speaking, in the coming five to eight years we will be launching about 100 satellites. Next year, the country's first lunar orbiter/fly mission is to fly. By 2012, China space planners will be landing a rover on the Moon surface. Based on success in the manned mission area, China intends to establish an orbiting space lab by 2015. In 2017, that country's lunar exploration plans call for robotic lunar sample return missions. China will also consider the possibility of manned mission to the Moon. Space.com
Next step, China's moon probe, Chang'e 1
Chang'e 1 will be outfitted with a stereo camera system to chart the lunar surface, an altimeter to measure the distance between the spacecraft and the lunar surface, a gamma/X-ray spectrometer to study the overall composition and radioactive components of the Moon, a microwave radiometer to map the thickness of the lunar regolith, and a system of space environment monitors to collect data on the solar wind and near-lunar region. Click here to read more about Chang'e 1.
Hot spot: The south pole of Neptune is warmer than the rest of the planet, at least right now, because its orbit is so large and slow. That portion of the planet has summer for 40 years. (Photo courtesy of NASA)Here on Earth, our coldest spots are on the poles. But go to Neptune and you’re singing a whole new tune.
Scientists have found that one of the coldest planets in our solar system has an unusual hot spot: its south pole. But don’t break out the sunscreen, swimsuits and sunglasses too fast.
Temperatures at Neptune’s south pole are about 18 degrees warmer than any other part of the planet, but the average temperature on the planet is 320 degrees below zero. And you thought Minnesota winters are harsh. An international team of astronmers just announced their temperature findings from the planet.
So why the difference?
Neptune’s south pole has been receiving summer sunlight for about 40 years. It’s mostly a function of how slow seasons change in a planet orbiting so far from the sun.
The planet is 2.8 billion miles from the sun. One Neptune year -- the time that it takes to make one complete orbit of the sun – is about 165 Earth years. Currently it’s south pole is in position for the perpetual sunshine, but that will all change in another 80 years or so, when the pole is in its winter position.
The frigid temperatures are the result of the Neptune getting just 1/900th the amount of sunlight that hits the Earth. So you probably can leave the sunscreen at home if you ever head that way.
Sputnik 1 starts space race 50 years ago
Sputnik 1: Oct. 4, 1957The "Sputnik crisis" was a turning point of the Cold War that began on October 4, 1957 when the Soviet Union launched the Sputnik 1 satellite. With its intercontinental ballistic missile, the R-7 Semyorka, Russia was first out of the starting blocks in the space race.
The "simplest satellite"
Called PS-1, for "Prosteishiy Sputnik" — the Simplest Satellite, Sputnik 1 weighing just 184 pounds, was built in less than three months. Soviet designers built a pressurized sphere of polished aluminum alloy with two radio transmitters and four antennas.
Sergey Korolyov
Sergey Korolyov, both visionary scientist and iron-willed manager, pressed the Kremlin to let him launch a satellite. The reaction of the world so impressed Khrushchev that he pressed Korolyov to do it again. Working round-the-clock, Korolyov and his team built another spacecraft in less than a month. On Nov. 3, they launched Sputnik 2, which weighed 1,118 pounds. It carried the world's first living payload, a mongrel dog named Laika, in its tiny pressurized cabin.
Sputnik creates initiatives in science and math
The Sputnik crisis spurred a whole chain of U.S. initiatives, including NASA, NSF, DARPA, and even the "New Math".
The finish line - stepping on the Moon
Russia continued its lead in the space race with a moon probe, a photo of the far side of the Moon, a human in orbit, a woman in orbit, extra-vehicular activity, landing a probe on another planet (Venus), and the first space station. The United States captured the biggest prize, though, putting a human on the Moon (July 20, 1969).
Skylights to possible Mars caves
NASA's Mars Odyssey spacecraft has discovered entrances to seven possible caves on the slopes of a Martian volcano.
Hot spots
Mars "caves": Image credit: NASA/JPL-Caltech/ASU/USGSUsing infrared imaging, the holes showed up as bright "hot spots" in photos taken during the cold of night (see right hand photo). In daytime shots they were colder than their surroundings (middle photo). The left photo uses the visable spectrum. This possible cave skylight informally called "Annie," has a diameter about double the length of a football field.
Seven Sisters
Seven SistersThe discovered holes, dubbed "Seven Sisters," are at some of the highest altitudes on the planet, on a volcano named Arsia Mons near Mars' tallest mountain.
What are they?
A report of the discovery of the possible cave skylights by Cushing and his co-authors was published online recently by the journal Geophysical Research Letters.
The new report proposes that the deep holes on Arsia Mons probably formed as underground stresses around the volcano caused spreading and faults that opened spaces beneath the surface. Some of the holes are in line with strings of bowl-shaped pits where surface material has apparently collapsed to fill the gap created by a linear fault. NASA.gov.
Explore the universe
Google SkyWant to explore the universe? With views of 100 million stars and 200 million galaxies, Google Sky lets you be a virtual space traveler with just a few clicks of a mouse.
Download Google Earth
To get started on your own outer-space adventure, download the most recent version of Google Earth software. Select "Switch to Sky" under the "view" menu or click on the icon that I show with a red arrow.
You might need a guide
The Universe is a big place so you might get lost. For help, the column on the left offer lots of guided tours. Try the sightseeing link under places. The screen capture shows what I found by selecting "Supernovae and Exotic Stars" under the layers section. PCworld has created a file of Google Sky Placemarks. Download it and open it with Google Earth. In the left column, in the Places box, click the (+) next to "Spectacular Sights in Google Sky". These are like bookmarks (or stick pins) that take you to some fantastic places. One (A Dramatic Outburst - V838Mon) has a time line slider so you can see how the event changed over several years.
Have fun
Google sky incorporates high-resolution images from NASA's Hubble Space Telescope, the Space Telescope Science Institute, the Sloan Digital Sky Survey, and the Digital Sky Survey Consortium into a fun, interactive learning tool. I hope you can check it out (high speed internet required).
Skull of Homo neanderthalensis: Photo courtesy Wikimedia Commons.A new study in the cause of Neanderthal man’s (Homo neanderthalensis) extinction counters a previous study that linked the demise to sudden changes in the southern Europe’s climate.
The new report, by a paleoanthropologist from Germany’s Max Planck Institute of Evolutionary Biology, claims that there is no discernible connection of the extinction of our closest evolutionary relatives to extreme climate change.
Published recently in the journal Nature, the new research is centered on the comparing of evidence gathered from deep-sea core drillings in Venezuela, and from sediments found at Gorham’s Cave, in southern Gibraltar, thought to be one of the last places inhabited by Neanderthals on the European continent.
Using radiocarbon dates of 32,000, 28,000 and 24,000 (which are thought to mark the demise of our stocky prehistoric cousins), professor Katerina Harvati and her team compared them to past climate data gathered from the deep-sea drilling cores.
"The more controversial date of circa 24,000 years ago, places the last Neanderthals just before a major climate shift that would have been characterized by a large expansion of ice sheets and the onset of cold conditions in northern Europe,” according to Harvati, who co- authored the paper.
"But Gibraltar's climate would have remained relatively unaffected, perhaps as a result of warm water from the sub-tropical Atlantic entering the western Mediterranean,” she said
Converting a radiocarbon date into a calendar year can be tricky, but the team came up with a method to correlate estimated dates of the species’ demise with records of past climate. The first two dates, 32,000 and 28,000 didn’t correlate with any extreme climatic changes. And the earlier date, 24,000, corresponded to a paleoclimate occurring before the onset of colder, more severe weather in northern Europe, and ice-sheet advancement.
But even then the authors say that the onset was hardly a sudden ice-age, but rather the beginning of a 1000-year gradual change in climate.
So if a sudden shift in climate didn’t kill off the Neanderthals, what did? The question remains open.
"This eliminates catastrophic climate change as a cause for extinction, but this leaves a whole range of other possibilities,” Harvati said.
LINKS
BBC website story
History of Gorham’s Cave
Early Modern Homo sapiens
