Stories tagged Earth and Space Science

Dec
16
2011

Science under attack
Science under attackCourtesy Mark Ryan
You’d think since the decision handed down in the Kitzmiller et al v. Dover court case in 2005 creationists would have given up trying to force their decidedly non-scientific views into public school science curricula. But apparently that’s hasn’t been the case. Those touting pseudo-scientific explanations such as intelligent design (creationism all dressed up in a monkey suit – as someone cleverly put it) are still at it, trying to get their religious-based ideas included in science classroom discussions.

A talk given by Steven Newton at this year’s Geological Society of America meeting in Minneapolis dealt with ways to counter the methods creationists use to push back against the information presented in earth science classes within the K-12 public school settings. The talk was one of several in a session titled, Geoscience Education X: Overcoming Threats to Earth and Space Science at K-12 Levels.

According to Newton, who’s with the National Center for Science Education (NCSE), the creationists’ methods amount to nothing less than sabotage.

Some of the feedback he said he heard from the nation’s public schools helps illustrate the kind of resistance earth science teachers continue to get from students, parents, and even school administrators. When a controversial subject such as evolution or climate change is being presented, teachers report being told to “tone it down” or “skip that chapter”* or to “teach both sides” (why just two sides? why not 200?). Newton said teachers also heard pleas of “don’t offend parents” from school administrators.

Of course, the earth sciences aren’t the only disciplines under attack. Just this past week, a story came out of Kentucky about how the school superintendent in Hart County complained in a letter to the state’s education commissioner and board of education members that he was concerned to learn that the state testing guidelines for biology considered evolution as a fact while at the same time “totally omitting the creation story by a God who is bigger than all of us.” It’s a harrowing example of the anti-science attitudes that are still prevalent in our country, and how creationists continue to threaten science education.

These don’t-rock-the-boat mitigations of scientific knowledge are harmful to science in general and aren’t doing the students any favors. Spoon-feeding watered down information or adding non-scientific knowledge into the mix confuses students and deprives them of a proper science education. Strong suggestions such as “teach the controversy” (when there is none) serves no purpose other than as a way to force religious or irrationally-based information into the public schools.

The anti-science crowd uses various means of attack to undermine geoscience knowledge in the schools and elsewhere. It questions the fossil record, pointing to something like the 19th century Piltdown Hoax as an example of how fossils and their interpretation can be faked. They make a huge leap of logic and argue that since one fossil was faked then all fossils must be questioned. The validity of radiometric dating is thrown into doubt with misinformation such and out-of-context or re-edited quotes from legitimate scientists, and even salted quotes.

Some worn-out creationist ploys have been lurking about for years, stories of dinosaurs spotted living in the Congo, fossil human footprints discovered alongside dinosaur tracks, a stegosaur figure found in the carvings of an ancient temple in Cambodia, a plesiosaur carcass hauled up from the depths by a Japanese trawler. These and other stories have either been thoroughly debunked or have failed to ever present any concrete evidence, yet continue to creep into otherwise serious evolution discussion,

The Internet is clogged with creationist viewpoints, some sites disguised with scientific-sounding domain names. This requires students to be alert and very careful about their research sources.

In hopes of legitimizing their point of view, creationist organizations of late have sponsored lectures and propaganda films in venues rented from legitimate scientific institutions such as they did at Southern Methodist University (SMU) and the California Science Center. When objections are raised and such events cancelled, the creationists proclaim it amounts to nothing less than censorship of ideas. But creationist ideas have always been poor in scholarship, lacking peer review or any kind of objective testing. Many are totally untestable.

Newton also warned against what he considers mistaken solutions to the problem of creationist pushback. Debating pseudo-scientists or giving their ideas equal time in the classroom only gives them unwarranted credibility. And why “teach the controversy” when there is none in the first place?

But, Newton insists that this doesn’t mean earth science teachers should avoid dealing with the pushback. Creationist tactics evolve over time, coming up with new ways to attack legitimate science. And just as new vaccines are developed to fight evolving flu viruses, science teachers need to stay a step ahead of the creationists and counter their anti-science attacks with a vaccine of cold, hard, scientific facts. Perhaps this affliction can be wiped out in our lifetimes.

SOURCES
What is Earth Science
Abstract for Steven Newton's GSA talk
The Creationist Movement: A Sociological View

*Attacks against science aren’t reserved only for the schools. Just this past week biologist and science-blogger PZ Myers alerted his readers to the fact that the Discovery Channel had purchased rights to broadcast the BBC documentary series by David Attenborough titled “Frozen Earth” but that it wouldn’t be including the last episode regarding climate change because the subject was too controversial. (Evidently, after a flood of well-deserved complaints the Discovery Channel has now reversed its decision and will air all seven episodes).

Dec
08
2011

Sonar study location along the Tonga Trench
Sonar study location along the Tonga TrenchCourtesy NOAA (with adaptation by author)
Here’s something you don’t see everyday: some very amazing images of a chain of mountains heading toward a subduction zone in the South Pacific. (Make sure you watch the video at the top of this story link - it seems to take a few seconds to load). The pictures were unveiled this week at the annual American Geophysical Union meeting held in San Francisco, California.

Researchers from Oxford and Durham universities took sonar readings along the bottom of the South Pacific northeast of New Zealand that show a chain of underwater mountains being dragged westward on the Pacific plate and subducted into theTonga Trench . This chasm is second only to the Marianas Trench in seabed depth – nearly 11 kilometers (6.6 miles) deep. The computer model created from the data shows one giant volcano at the very edge of the trench breaking into huge blocks and beginning to collapse into the abyss. It’s actually pretty cool to see. Earthquakes occur less frequently near where the volcanoes are being gobbled up, and scientists differ on whether the giant broken chunks of the volcano help or hinder the subduction process, but the images clearly show the mechanism at work.

Illustration of plate boundaries and subduction
Illustration of plate boundaries and subductionCourtesy USGS
According to the theory of plate tectonics both oceanic crust and continental crust ride atop rigid plates that migrate slowly across the globe, colliding with and pulling away from each other. There are three main types of boundary zones created by this movement: convergent (moving toward each other), divergent (moving away from each other) and transform (moving side by side). In the first example, which is the type this article deals with, the lighter oceanic plate (Pacific Plate) is subducting under the heavier continental plate (Indo-Australian Plate). The process is part of the creation and recycling of the Earth’s lithosphere – that is it’s rocky crust along with the uppermost part of the mantle. Some mantle material is forced upward in the process, and the land near these subduction zones – like that in Japan and along the coast of Chile in South America - is often populated with volcanoes. This collision of plates causes tremendous tensions to build up along the contact zone. The extreme pressure can continue building over hundreds or even thousands of years until it's too much, and the plates start to shift. All the pent-up energy is suddenly released in fits and starts in the form of earthquakes and aftershocks, as happened this year (and is still happening) in Sendai, Japan and Christchurch, New Zealand.

The underwater volcanic chain spreads across the ocean bottom in a southeasterly direction for several thousands kilometers as each mountain makes it way westward toward the trench at the rate of about 6cm per year. That's about as fast as your fingernails grow in two months. The sonar images were taken at a depth of six kilometers below the ocean surface as part of a project funded by Australia’s Natural Environment Research Council (NERC) to help determine if the massive debris from the crumbling volcanoes have any effect on the frequency of earthquakes and tsunamis in the area.

SOURCE
BBC report

Nov
21
2011

Phil Plait, astronomer, lecturer, and blogger at Bad Astonomy gives a humorous and informative talk about asteroid impacts both in the past and in the future. He touches on the asteroid that wiped out the dinosaurs 65 million years ago, and the 50 meter-wide asteroid that created Meteor Crater in the Arizona desert 50,000 years ago, and the rocky bolide that exploded with the force of 1000 atomic bombs above the Tunguska river region in Siberia in 1908. Each impacted with Earth, and lucky for us, they all took place safely in the past. But you know it’s bound to happen again. It’s not a question of if, but one of when. And when could be sooner than you think. Plait ratchets up his talk’s anxiety level with the information that an asteroid discovered in 2004 and known as Apophis is headed toward Earth. This thing isn’t anywhere as huge as the 6-mile wide space rock that ended the reign of the dinosaurs, but at over 250 meters across it could still do some serious damage.

In 2029, Apophis will pass so close to Earth it will come inside the orbit of some of our weather satellites. It won’t strike our planet at that time but if it manages to pass through a small kidney-shaped region in known as a gravitational keyhole, Earth’s pull would redirect Apophis orbit into one that would set it on a path of collision with us the next time it comes around on April 13, 2036. Sure the odds are slim everything will actually line up right for this to happen, but Plait sees it as an opportunity for us to learn how to deal with such events. We know impacts happened in the past, and we can assume they'll continue to happen in the future. Apophis is a good example of that. So it makes sense to start planning on how we can defend against such an event. Scientists from organization such as the B612 Foundation and NASA are already trying to raise public awareness of the dangers asteroids and other near Earth objects may pose to the future of our planet. And Plait explains some interesting counter offensives already being considered. It won't be an easy task but it's probably one that needs planning just in case. Besides, look at what could happen if we don't. It's a no-brainer.

MORE INFO
More about Apophis
Asteroid Watch website

Nov
16
2011

In this video renowned paleontologists Bob Bakker and Peter Larson visit the CK Preparations lab in Montana to examine the incredible discovery by Clayton (“Dino Cowboy”) Phipps of the remains of a tyrannosaurid and some sort of ceratopsian dinosaur preserved together (and touching) in a single block of rock from the Hell Creek Formation. Both skeletons are articulated, nearly 100 percent intact, and in a wonderful state of preservation. Teeth matching those remaining in the tyrannosaurid jaws are preserved imbedded in the ceratopsian skeleton. The predator’s skull, which is speculated to be that of a Nanotyrannus, shows signs of being kicked in. Early analysis of the geology of the matrix encasing the find suggests that the two battling dinosaurs may have gotten trapped in mire or overcome by a sudden environmental catastrophe, like a cave-in. Was this a unique moment frozen in time of a battle between a predator and its prey? Do the two "combatants" represent entirely new genera of dinosaurs? These questions require further study and preparation of this very unusual fossil.

Smithsonian’s “Tracking Dinosaurs” site
Paleo-Incident Project

Nov
04
2011

Teeth tell tales of travel: Ratio of oxygen isotopes in Camarasaurus teeth reveals that the sauropod migrated long distances to find food and water. Geological Museum, University of Wyoming, Laramie, WY
Teeth tell tales of travel: Ratio of oxygen isotopes in Camarasaurus teeth reveals that the sauropod migrated long distances to find food and water. Geological Museum, University of Wyoming, Laramie, WYCourtesy Mark Ryan
Ever wonder how something as big as a sauropod dinosaur was able to grow so large? Sauropods were those huge, long-necked quadrupeds estimated to have weighed anywhere from 50 to 120 tons, and with lengths of up to 200 feet. Just seeing the skeleton of any one of them – the Apatosaurus, Diplodocus, Brachiosaurus, Ultrasaurus or any their kind – you just know those Jurassic giants had to be on a constant eating binge to maintain their massive size. But just how much food could a single area supply? Doesn’t it make sense that these critters would have eaten up any food source within the reach of their extensive necks? Then what would they do?

A new study of sauropod teeth has produced some strong evidence that the giant herbivores migrated during times of drought or other environmental stresses, searching for new untapped food and water sources. Geochemist Henry Fricke of Colorado College in Colorado Springs along with student colleagues Justin Hencecroth and Marie E. Hoerner studied the teeth of various Camarasaurus specimens comparing the ratio of oxygen isotopes found in the enamel with the ratio found in the sedimentary rock deposits where the teeth were found. By sauropod standards, Camarasaurus was one of the smaller ones, but it's the most common sauropod found in the Morrison Formation deposits.

Camarasaurus skeleton
Camarasaurus skeletonCourtesy Public domain
During its lifetime 145 million years or so in the past, a Camarasaurus's teeth would absorb the isotopes ratio of its environment, that is the ratio of the oxygen isotopes found in the local water supply. So Fricke’s team sampled 32 camarasaur teeth, taking measurements of the younger enamel found near the base of each tooth with the older enamel near the crown. In some cases, the isotopes ratios in the enamel matched those of the sedimentary rocks from where the teeth were found. But some enamel didn’t match. This meant the dinosaur must have migrated at some time to higher ground, more than likely in search of a better food source.

"In a theoretical sense, it's not hugely surprising,” Fricke said. “They are huge — they would probably have eaten themselves out of house and home if they stayed in one place.”

So the camarasaurs did what any hungry animal would do: they headed out in search of more food, even if it meant a migration of 200 miles into the higher regions and back. Seasonal droughts were probably another factor. The highlands would have had more rainfall and therefore more vegetation and water. When the wet season returned to the basin so would the camarasaur herds. Fricke estimates the seasonal herbivore hikes took around five months to complete. He also thinks if one kind of sauropod migrated, other genera probably did the same, and an analysis of their teeth would probably show similar results.

SOURCES and LINKS
Abstract in Nature
Nature News
Paleoclimatology: the Oxygen Balance
Camarasaurus facts

Oct
30
2011

Thailand Flooding from Space
Thailand Flooding from SpaceCourtesy NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team
From the NASA Image of the Day on October 28:

Since July 2011, heavy monsoon rains in southeast Asia have resulted in catastrophic flooding. In Thailand, about one third of all provinces are affected. On Oct. 23, 2011, when this image from ASTER, the Advanced Spaceborne Thermal Emission and Reflection Radiometer instrument on NASA's Terra spacecraft was acquired, flood waters were approaching the capital city of Bangkok as the Ayutthaya River overflowed its banks. In this image, vegetation is displayed in red, and flooded areas are black and dark blue. Brighter blue shows sediment-laden water, and gray areas are houses, buildings and roads. The image covers an area of 35.2 by 66.3 miles (56.7 by 106.9 kilometers) and is located at 14.5 degrees north latitude, 100.5 degrees east longitude.

With its 14 spectral bands from the visible to the thermal infrared wavelength region and its high spatial resolution of 15 to 90 meters (about 50 to 300 feet), ASTER images Earth to map and monitor the changing surface of our planet. ASTER is one of five Earth-observing instruments launched Dec. 18, 1999, on Terra. The instrument was built by Japan's Ministry of Economy, Trade and Industry. A joint U.S./Japan science team is responsible for validation and calibration of the instrument and data products. The broad spectral coverage and high spectral resolution of ASTER provides scientists in numerous disciplines with critical information for surface mapping and monitoring of dynamic conditions and temporal change.

Oct
26
2011

Trajectory of comet Elenin
Trajectory of comet EleninCourtesy NASA/JPL-Caltech
Below is a news release from NASA/JPL about a comet that is going through some difficult times. NASA is sort of harsh in this release, imho, and really does not take the comet's feelings into account. Take a gander to see what I mean. Even the title is a little severe.

NASA Says Comet Elenin Gone and Should Be Forgotten

Comet Elenin is no more.

Latest indications are this relatively small comet has broken into even smaller, even less significant, chunks of dust and ice. This trail of piffling particles will remain on the same path as the original comet, completing its unexceptional swing through the inner solar system this fall.

"Elenin did as new comets passing close by the sun do about two percent of the time: It broke apart," said Don Yeomans of NASA's Near-Earth Object Program Office in Pasadena, Calif. "Elenin's remnants will also act as other broken-up comets act. They will trail along in a debris cloud that will follow a well-understood path out of the inner solar system. After that, we won't see the scraps of comet Elenin around these parts for almost 12 millennia."

Twelve millennia may be a long time to Earthlings, but for those frozen inhabitants of the outer solar system who make this commute, a dozen millennia give or take is a walk in the celestial park. Comet Elenin came as close as 45 million miles (72 million kilometers) to the sun, but it arrived from the outer solar system's Oort Cloud, which is so far away its outer edge is about a third of the way to the nearest star other than our sun.

For those broken up over the breakup of what was formerly about 1.2 miles (two kilometers) of uninspiring dust and ice, remember what Yeomans said about comets coming close to the sun – they fall apart about two percent of the time.

"Comets are made up of ice, rock, dust and organic compounds and can be several miles in diameter, but they are fragile and loosely held together like dust balls," said Yeomans. "So it doesn't take much to get a comet to disintegrate, and with comets, once they break up, there is no hope of reconciliation."

Comet Elenin first came to light last December, when sunlight reflecting off the small comet was detected by Russian astronomer Leonid Elenin of Lyubertsy, Russia. Also known by its astronomical name, C/2010 X1, Elenin somehow quickly became something of a "cause célèbre" for a few Internet bloggers, who proclaimed this minor comet could/would/should be responsible for causing any number of disasters to befall our planet.

Internet posts began appearing, many with nebulous, hearsay observations and speculations about earthquakes and other disasters being due to Elenin’s gravitational effects upon Earth. NASA’s response to such wild speculations was then in turn speculated to be an attempt to hide the truth.

"I cannot begin to guess why this little comet became such a big Internet sensation," said Yeomans. "The scientific reality is this modest-sized icy dirtball's influence upon our planet is so incredibly miniscule that my subcompact automobile exerts a greater gravitational influence on Earth than the comet ever would. That includes the date it came closest to Earth (Oct. 16), when the comet’s remnants got no closer than about 22 million miles (35.4 million kilometers)."

Yeomans knows that while Elenin may be gone, there will always be Internet rumors that will attempt to conjure up some form of interplanetary bogeyman out of Elenin, or some equally obscure and scientifically uninteresting near-Earth object. Thinking of ways to make himself any more clear about the insignificance of this matter is somewhat challenging for a scientist who has dedicated his life to observing asteroids and comets and discovering their true nature and effects on our solar system.

"Perhaps a little homage to a classic Monty Python dead parrot sketch is in order," said Yeomans. "Comet Elenin has rung down the curtain and joined the choir invisible. This is an ex-comet."
NASA detects, tracks and characterizes asteroids and comets passing relatively close to Earth using both ground- and space-based telescopes. The Near-Earth Object Observations Program, commonly called "Spaceguard," discovers these objects, characterizes the physical nature of a subset of them, and predicts their paths to determine if any could be potentially hazardous to our planet. There are no known credible threats to date.

Its like the person writing this had a personal vendetta against this poor comet. Though the Monty Python reference at the end helps lighten the mood, the overall dismissive tone of this news release is a bit sad.

Poor Elenin and its remaining "piffling particles".

Oct
21
2011

Soyuz VS01 at Launch Pad in French Guiana
Soyuz VS01 at Launch Pad in French GuianaCourtesy ESA

This morning (October 21, 2011), at 10:30 Greenwich Mean Time (5:30am Central Daylight Time), a Soyuz rocket lifted off from a brand new launch pad in the South American jungle with two European navigation satellites, making history on its first mission from Guiana Space Center. Russia and Europe opened the new Soyuz launch site to allow the Russian rocket to better compete for commercial and European space missions. By launching close to the equator in French Guiana, the Soyuz rocket gets a boost in performance.

In 1998, the European Space Agency (ESA) first began studying the possibility of Soyuz launches from the Guiana Space Center. ESA officially started this program in 2004, with construction work in French Guiana beginning in 2005 and the first Russian components arriving three years later, in 2008.

This launch, designated VS01 in Arianespace’s launcher family numbering scheme, will deploy two Galileo satellites. Galileo is Europe’s program for a global navigation satellite system to provide highly accurate, global positioning services, and will be interoperable with the U.S. Global Positioning System and Russia’s Glonass network.

The newspaper El Mundo has an informative animation on the launch vehicle and Galileo satellite (in Spanish).

See video

Oct
15
2011

Giant bison skull: its horns spanned 6 feet 4 inches. Behind stands Dr. Steve Holen, curator of archaeology at the Denver Museum of Nature & Science
Giant bison skull: its horns spanned 6 feet 4 inches. Behind stands Dr. Steve Holen, curator of archaeology at the Denver Museum of Nature & ScienceCourtesy Photo by Heather Rousseau ©Denver Museum of Nature and Science
The last talk I attended at the Geological Society of America (GSA) convention this past week was one of my favorites. It was an update of the Snowmastodon Project given by Kirk Johnson, chief curator at the Denver Museum of Nature and Science (DMNS). Just one year ago, a construction worker bulldozing for a dam-building project at the Zeigler Reservoir near Snowmass Village in Colorado unearthed a mammoth tusk. Paleontologists and archaeologists from the Denver museum were called in, and excavation of a small portion of the drained reservoir bottom soon got underway. The museum crew worked for just one month, until November 14, 2010, when snowfall halted the project. Then last spring scientists returned to the site and were allowed just 51 days to excavate the fossil deposits before the Snowmass Water and Sanitation District resumed their expansion work on the reservoir.

This time more research experts from the US, Canada, and England joined the dig along with a slew of interns and volunteers, totaling some 233 people working on the project. Over the next seven weeks excavation at the Zeigler Reservoir site progressed at a frantic pace. According to Johnson, anywhere from 15 to 90 diggers were on site each day digging out fossils from the ancient peat and mud deposits, from what once were the shores of a small glacial lake. Despite the short window of opportunity, the sheer number and diversity of fossils from the dig site has been truly remarkable.

American Mastodon: (Mammut americanum)
American Mastodon: (Mammut americanum)Courtesy Dantheman9758 at en.wikipedia
Of the nearly 5000 bones and skulls exhumed from the Snowmass fossil site, more than 60 percent were of mastodons (Mammut americanum) representing at least 30 individuals in various stages of life. The other 40 percent of the fauna included mammoths (Mammuthus columbi), camels, horses, giant bison (Bison latifrons) and ground sloths (Megalonyx jeffersonii), otters, muskrats, minks, bats voles, chipmunks, beavers, bats, rabbits, mice, salamanders, frogs, lizards, snakes, fish, and birds, and iridescent beetles. No large carnivore remains were found in the deposits, and human remains were absent as well, although archaeological techniques were used during the dig just in case any were uncovered.

Flora from the prehistoric tundra environment included pollen, green leaves and cones, and tree logs, some with their bark still intact.

So far, age estimates for the deposits range between 43, 000 to 130,000 years old although further dating tests should narrow that down.

The talk included several photos of what Johnson termed “Flintstone moments”, i.e. shots of field workers posing with massive mammoth or mastodon femurs or tibia. And Johnson marveled at the incredible state of preservation of many of the fossils displayed. Some of the bones, he said, still emitted a very strong funk.

In terms of sheer number of bones and ecological data, Snowmastodon ranks up there as probably one of the best high altitude Ice Age ecology sites in the world, and certainly the best mastodon fossil site. A team of researchers at the DMNS lab will spend the next year and a half cleaning, cataloging, and analyzing all the fossils found at the Snowmass dig site, water was to be reintroduced into the reservoir on Oct. 13. Despite the loss of the site, the field crew did a tremendous job in the time they were given to excavate the fossil-rich site. And Kirk Johnson didn’t hide his excitement. In closing his talk, he said “It was one hell of a year!”

FURTHER INFO
The Snowmastodon Project website
Photo set on Flcker

Oct
06
2011

Sputnik 1
Sputnik 1Courtesy NASA
From NASA’s Image of the Day this past Tuesday:

On Oct. 4, 1957, Sputnik 1 successfully launched and entered Earth's orbit. Thus, began the space age. The successful launch shocked the world, giving the former Soviet Union the distinction of putting the first human-made object into space. The word 'Sputnik' originally meant 'fellow traveler,' but has become synonymous with 'satellite' in modern Russian.

This past September 30, almost exactly 54 years later, China launched their first inhabitable space laboratory module, Tiangong-1. The module, a part of a large and ambitious national space program, is the first step in placing a larger modular space station in orbit by 2020.
Combine this effort with Chinese plans to visit the moon and a manned Mars mission, could this be the beginning of a new space race? Personally, I hope so. NASA needs a kick in the pants, and a little “friendly” competition with China could push NASA and its partners in a good way.