Bill Nye gives us a quick, and fun, lesson on how we can avoid problem asteroids of the future.
It's been happening the past few summers, but researchers say it's getting bigger each season. It is a lake covering the North Pole during these summer months caused by ice melting in the summer sun. This year's lake formedn on July 13 and is about a foot deep. And since water absorbs more solar radiation than ice, researchers expect this lake to keep growing each season ass the ice underneath gets thinner.
Courtesy Mark RyanI've had the great fortune of being able to volunteer in the paleontology lab at the Science Museum of Minnesota. I'm in my fourth month there and it's been a real blast. My first project was preparing (cleaning) the skull of a small oreodont collected from the White River Formation in Wyoming. This is the same formation exposed in the fossil-rich South Dakota Badlands. By cleaning, I mean removing all the rock (matrix) in which the skull is encased. I've also helped patch up the casts of a couple of lambeosaurus skulls, and spent a few days puzzling over a crocodile skull reduced to about 1000 pieces.
Courtesy Mark RyanAt the moment, preparators been working on the remains of a 52 million year-old gar collected from the Green River Formation in southwestern Wyoming. Most of the work is being done by the more experienced volunteers in the lab but I've been able to help a little, taking my turn with the air scribe to reveal some caudal scales in their rocky grave. This particular specimen, an ancient member of Lepisosteus, was collected in Lincoln County, Wyoming. It's fascinating work uncovering something that last saw sunlight more than 50 million years ago. Now, at least, its remains can bask in the glare of the paleo lab's artificial lights.
Courtesy Mark RyanFifty some million years ago, the gar lived in a large body of water known as Fossil Lake, one of three intermountain lakes that existed at different times in a sub-tropical environment in that part of Wyoming. The intermountain basin in and around the lake teemed with both floral and faunal life that over about 4000 years lived and died and were fossilized forming one of the great Lagerstätten in the world. The surrounding mountains were composed mainly of limestone, and the rivers and streams eroding those mountains carried high levels of calcite (CaC3) into the lake, resulting in a high sedimentation rate that added to the ideal fossilization environment.
Most of the fossils coming out of the Fossil Lake strata have been fossilized by a process called permineralization, where mineral-rich water permeates all the spaces and pores in the skeleton and the minerals (in this case calcite) crystallize out of the water replacing bone material down to the cellular level. Some carbonization is also involved. This process depletes the remains of volatiles and is caused by the heat and pressure of sediment compression, which also crushes and flattens the fossils, and tends to color them either brown or black.
Courtesy Mark RyanThat's very apparent with our gar. Although only portions of the fish's remains have been exhumed (its head and tail) the fossil is already providing some information about what followed the gar's death (taphonomy). Lepisosteus favored the shallow, swampy edges of Fossil Lake and when it died it probably floated on the surface for a while giving bacteria time to enter its mouth and gills and begin their decomposition work before the corpse was buried beneath sediments.
We can deduce this scenario by the manner the remains are preserved. The bones of the gar's skull and jaws are scattered and jumbled in a mish-mash of bones and scales. The head appears to have been blown apart, and that's probably what happened. As the microbes feasted on the fish's head, they released gases inside the corpse which built up, and bloated the gar to a point where it burst from the internal pressure. The mandibles, the cranium, and other bones broke apart before settling to the bottom and are disarticulated. The very end of the tail, however, shows no such disruption. The rays of the caudal fins looking almost as fresh as they did when the gar died half a million centuries ago.
Courtesy Mark RyanThe scales of its mid-section are beginning to come to light. These diamond-shaped structures were covered with ganoin, an enamel-like tissue containing less than five percent organic material. The mineralized tissue gave Lepisosteus a very tough, predator-resistant exterior when it was alive but not so resistant to the bacteria that attacked the gar from the inside after it died. Preliminary work of the mid-section is showing signs of decomposition there but further work required.
One of the major experts on the fossils found in the Green River Formation is Lance Grande, a graduate of the University of Minnesota (and elsewhere) who has been working at Chicago's Field Museum for the past few decades. In the early '80s, Dr. Grande wrote a hefty bulletin titled Paleontology of the Green River Formation for the Wyoming Geological Survey, and has now come out with a new book titled The Lost World of Fossil Lake: Snapshots from Deep Time. In a recent television interview, Dr. Grande talked about his book and about the fossils found in the Green River Formation.
Hundreds of thousands of finely preserved fossils from Fossil Lake deposits can be found in museum displays and on rock shop shelves world-wide. The best fossils were buried quickly and preserved in near pristine condition. Many of these come from what used to be the deep center of the lake where conditions were probably anoxic and burial fairly swift. At times during Fossil Lake's history events like seasonal algal blooms or rapid turnovers of the water column occurred and caused massive die-offs of fishes. Other fish, like our gar, probably just died a regular death.
Courtesy Mark RyanEvery fossil tells a story, and our gar is no exception. Back in the Eocene epoch it lived for a short time in the then subtropic environment of southwest Wyoming, doing what gars do before it finally died along the shores of Fossil Lake. After it was buried, it was fossilized, dug up, and transferred to the collections vault of the Science Museum of Minnesota. A few months ago, it was retrieved from the vault and brought into the paleo lab where it's been worked on each week by several people. Whatever the gar was thinking when it was alive back in the late Eocene, you can be sure it was unaware that its post-mortem life would provide hours of detailed work, study and fascination for another curious life-form 52 million years later.
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Researchers at the University of Adelaide have developed a new nanomaterial that could help reduce CO2 emissions produced by coal-fired power plants. This new material acts like a sponge and “soaks up” the carbon dioxide before it is released into the atmosphere by trapping the CO2 molecules in tiny nano-sized pores. This new material is potentially much more energy efficient than other, current methods of separating out CO2 from power plant emissions.
Courtesy SMMOn Youth Science Day, the KAYSC Heritage Crew joined the Archaeology Lab's open house, located behind the Dinosaur exhibit on the 3rd floor. There, archaeologists presented unique Oneota artifacts that were digged up in the 1959-1960 Sheffield Site excavation.
One of the interesting things that we learned is about the two garden hoes that were found on different two sites, St. Croix (Sheffield) and Red wing. Both are made from a animal shoulder blade and are used for the same purpose, but are not from the same local resources. One was made from a white-tailed deer at St. Croix (Sheffield) and the other was made from a bison at Red Wing. Does the Oneota have a connection with another tribe? Is this a sign of trade or technology exchange?
Courtesy NASA/JPL/Space Science Institute During the Apollo lunar missions in the late 60s and early 70s, many of the astronauts remarked at how small Earth seemed from the Moon. On this anniversary of his first steps on the lunar surface, I wonder what Neil Armstrong would have thought of this remarkable photograph taken yesterday by the Cassini spacecraft? In the center of a field of stars sits planet Earth and the Moon taken from more than 898,000,000 miles away!
Courtesy NASAForty-four years ago today, I was laying on the beach at Park Point in Duluth, Minnesota when those famous words, "The Eagle has landed" came over my little transistor radio, signaling Apollo astronauts Neil Armstrong's and Buzz Aldrin's successful landing of their spacecraft on the Moon. That evening, I was working my shift at a local restaurant, busing tables. The manager (thankfully) had placed a television in the dining area so patrons (and I) could watch as Armstrong made his monumental first steps on the lunar surface. The rest, of course, is history.
Courtesy NASA/JPL-CaltechHey, everybody. Heads up! Today (July 19, 2013), at approximately 4:27 CDT the Cassini spacecraft, which is 898 million miles away, will take a snapshot from the other side of Saturn that will include not only the ringed planet but our very own planet Earth. The photo op will last for about 15 minutes. Perfect time for a photobomb don't you think?
The Kitty Andersen Youth Science Center
Courtesy KAYSC has a new crew on the block! The Heritage Crew is going to be working in the Archeology department in the museum and will be working out at an archeological dig site called Sheffield Site. They'll be digging up artifacts belonging to the Oneota along the St. Croix River. In August, they will also excavate the sites and process the artifacts back at the museum. Currently, they are learning about the different types of stone used at the site that the Oneota used for stone tools (lithics), the pottery at the site, and bones (faunal material). Most of the material dates to around 2000 years old. Follow us on Facebook at The Sheffield Site!
Courtesy JJ HarrisonWith all the rain we've had this summer, the conditions are prime for creating large mosquito populations. And researchers have now figured out certain factors – like blood type – that can make people be more tasty targets for the little buzzers. Question, do you think mosquitoes prefer to strike beer drinkers? Click here to find the answer to that, and other factors that can impact your appeal to mosquitoes.