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The Platypus is stranger than you think.

Platypuses have no nipples.  After the young hatch, the mother oozes milk from the pores all over her body.

The male platypus has a poison barb on the inside of its hind legs.  The purpose of this weapon is uncertain.

While often compared to the beaver, the platypus is only about 20 inches in length -- more comparable to the size of the muskrat.

The Platypus bill is actually just an elongated muzzle covered with much the same kind of tough skin found on a dog's nose.  This bill contains an electrically-sensitive organ that can detect the electrical signatures of the small aquatic animals it eats.

Everything Biology
LROC's first look at the Apollo landing sites PDF Print E-mail
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Written by Everything Science   
Jul 17, 2009 at 12:00 AM

The imaging system on board NASA's Lunar Reconnaissance Orbiter (LRO) recently had its first of many opportunities to photograph the Apollo landing sites. The Lunar Reconnaissance Orbiter Camera (LROC) imaged five of the six Apollo sites with the narrow angle cameras (NACs) between July 11 and 15, within days of the 40th anniversary of the Apollo 11 mission.

The early images obtained by LROC, operated by Arizona State University Professor Mark Robinson, show the lunar module descent stages left behind by the departing astronauts. Their locations are made evident by their long shadows, which result from a low sun angle at the time of collection.

 
Concordia
The Apollo 14 lunar module (LM Antares) and the Apollo Lunar Surface Experiment Package are visible in this image (note the astronaut tracks between the two artifacts). At the current altitude and lighting the descent stage is clearly visible with its angular shadow (right) and shadow cast by leg (near arrow tip). The LROC NAC image data has not been calibrated, the faint vertical stripes are a natural part of the image and will be removed later after the full suite of calibration data is collected during the commissioning phase.

Credit: NASA/GSFC/Arizona State university

"In a three-day period we were able to image five of the six Apollo sites – the LROC team anxiously awaited each image," says LROC Principal Investigator Mark Robinson, professor in the School of Earth and Space Exploration in ASU's College of Liberal Arts and Sciences. "Of course we were very interested to get our first peek at the lunar module descent stages just for the thrill – and to see how well the cameras had come into focus."

For additional information about the LROC instrument and to view the first Apollo landing site images, visit: http://lroc.sese.asu.edu.

The orbiter's current elliptical orbit resulted in image resolutions from the NACs that were slightly different for each site but were all about four feet per pixel. Since the deck of the descent stage is about 14 feet in diameter, the Apollo relics themselves fill about four pixels. However, because the Sun was low to the horizon when the images were acquired, even subtle variations in topography create long shadows. Standing just over ten feet above the surface, each Apollo descent stage creates a distinct shadow that fills roughly 20 pixels.

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Primitive asteroids in the main asteroid belt may have formed far from the sun PDF Print E-mail
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Written by Everything Science   
Jul 15, 2009 at 12:00 AM

Many of the objects found today in the asteroid belt located between the orbits of Mars and Jupiter may have formed in the outermost reaches of the solar system, according to an international team of astronomers led by scientists from Southwest Research Institute (SwRI).

The team used numerical simulations to show that some comet-like objects residing in a disk outside the original orbit of the planets were scattered across the solar system and into the outer asteroid belt during a violent phase of planetary evolution.

 
Concordia
Researchers collected this micrometeorite in the vicinity of CONCORDIA station in central Antarctica (Dome C, 73°S, 123°E).

Credit: CSNSM-Orsay-CNRS / IPEV

Usually, the solar system is considered a place of relative permanence, with changes occurring gradually over hundreds of millions to billions of years. New models of planet formation indicate, however, that at specific times, the architecture of the solar system experienced dramatic upheaval.

In particular, it now seems probable that approximately 3.9 billion years ago, the giant planets of our solar system -- Jupiter, Saturn, Uranus and Neptune -- rearranged themselves in a tumultuous spasm. "This last major event of planet formation appears to have affected nearly every nook and cranny of the solar system," says lead author Dr. Hal Levison of SwRI.

Key evidence for this event was first identified in the samples returned from the Moon by the Apollo astronauts. They tell us about an ancient cataclysmic bombardment where large asteroids and comets rained down on the Moon.

Scientists now recognize that this event was not limited solely to the Moon; it also affected the Earth and many other solar system bodies. "The existence of life on Earth, as well as the conditions that made our world habitable for us, are strongly linked to what happened at this distant time," states Dr. David Nesvorny of SwRI.

The same dynamical conditions that devastated the planets also led to the capture of some would-be impactors in the asteroid belt. "In the classic movie 'Casablanca,' everybody comes to Rick's. Apparently throughout the solar system, the cool hangout for small objects is the asteroid belt," says Dr. William Bottke of SwRI.

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Straighten up and fly right: Moths benefit more from flexible wings than rigid PDF Print E-mail
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Written by Everything Science   
Jun 29, 2009 at 12:00 AM

Most scientists who create models trying to understand the mechanics and aerodynamics of insect flight have assumed that insect wings are relatively rigid as they flap.

New University of Washington research using high-speed digital imaging shows that, at least for some insects, wings that flex and deform, something like what happens to a heavy beach towel when you snap it to get rid of the sand, are the best for staying aloft.

hawk moth
The wing of a Manduca sexta, or tobacco hawkmoth, reveals the extent of deformation during flight.

Credit: Armin Hinterwirth, University of Washington

"The evidence indicates that flexible wings are producing profoundly different air flows than stiff wings, and those flows appear to be more beneficial for generating lift," said Andrew Mountcastle, a UW doctoral student in biology.

He used particle image velocimetry, a technique commonly used to determine flow velocities in fluids, to study how air flows over the wings of Manduca sexta, or tobacco hawkmoths. The method combined laser light and high-speed digital video to model air flow.

A hawkmoth's wings are controlled by muscles on the insect's body and have no internal muscles of their own. The bulk of the wing is something like fabric stretched back from a stiff leading edge, fabric that is elastic and bends from inertia as the wing accelerates or decelerates through each stroke.

To test the wings' function, they were attached to mechanical "flappers" that moved back and forth 25 times a second, the same frequency at which the moths flap their wings, with the focus on how the wings deformed with each motion reversal. While the machine placed the wings at the same dominant angle as in normal moth flight, it could only approximate natural motion in one axis of rotation, compared with the three axes controlled in actual moth flight.

For the research, wings were removed from moths and tested in the mechanical "flapper" immediately, while they maintained most of their natural elasticity. After that the wings were allowed to dry for 12 to 24 hours and covered with enough spray paint to restore their original mass, then the wings were tested again in their more rigid state. The high-speed video, when viewed in slow motion, provided graphic detail of how the wings deformed as they flapped.

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Melon research sweetened with DNA sequence PDF Print E-mail
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Written by Everything Science   
Jun 28, 2009 at 12:00 AM

COLLEGE STATION - People smell them, thump them and eyeball their shape. But ultimately, it's sweetness and a sense of healthy eating that lands a melon in a shopper's cart.

Plant breeders now have a better chance to pinpoint such traits for new varieties, because the melon genome with hundreds of DNA markers has been mapped by scientists with Texas AgriLife Research. That means tastier and healthier melons are likely for future summer picnics.

"This will help us anchor down some of the desirable genes to develop better melon varieties," said Dr. Kevin Crosby, who completed the study with Drs. Soon O. Park and Hye Hwang. "We can identify specific genes for higher sugar content, disease resistance and even drought tolerance."

melons
Melons -- they come in all sizes, shapes and colors. People around the world love them. Researchers at Texas AgriLife Research have mapped the melon genome with hundreds of DNA markers.

Credit: Texas AgriLife Photo by Kathleen Phillips

The results are reported in the Journal of the American Society of Horticultural Sciences.

Melons are fleshy, edible cucurbits grown worldwide in a multitude of varieties. Not only are they economically important, the scientists noted, but they are a favorite among consumers internationally.

The average person in the U.S. eats about 25 pounds of melon every year, according to the Agricultural Marketing Resource Center at Iowa State University.

Scientists from France and Spain already had completed partial maps of segments of the melon DNA sequence. The Texas researchers connected those segments with new findings in their study to complete the entire melon genome map.

For the study, the Deltex ananas melon was crossed with a wild melon called TGR 1551. More than 100 of the offspring from that cross were grown in the AgriLife Research greenhouses at Weslaco, Crosby noted.

DNA was extracted from leaf tissue collected 21 days after planting. Results from these tests were integrated into partial maps created by other researchers.

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University of Colorado team finds definitive evidence for ancient lake on Mars PDF Print E-mail
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Written by Everything Science   
Jun 17, 2009 at 12:00 AM

A University of Colorado at Boulder research team has discovered the first definitive evidence of shorelines on Mars, an indication of a deep, ancient lake there and a finding with implications for the discovery of past life on the Red Planet.
 

 
earth
This is reconstructed landscape showing the Shalbatana lake on Mars as it may have looked roughly 3.4 billion years ago. Data used in reconstruction are from NASA and the European Space Agency.

Image credit: G. Di Achille, University of Colorado

Estimated to be more than 3 billion years old, the lake appears to have covered as much as 80 square miles and was up to 1,500 feet deep -- roughly the equivalent of Lake Champlain bordering the United States and Canada, said CU-Boulder Research Associate Gaetano Di Achille, who led the study. The shoreline evidence, found along a broad delta, included a series of alternating ridges and troughs thought to be surviving remnants of beach deposits.

"This is the first unambiguous evidence of shorelines on the surface of Mars," said Di Achille. "The identification of the shorelines and accompanying geological evidence allows us to calculate the size and volume of the lake, which appears to have formed about 3.4 billion years ago."

A paper on the subject by Di Achille, CU-Boulder Assistant Professor Brian Hynek and CU-Boulder Research Associate Mindi Searls, all of the Laboratory for Atmospheric and Space Physics, has been published online in Geophysical Research Letters, a publication of the American Geophysical Union.

Images used for the study were taken by a high-powered camera known as the High Resolution Imaging Science Experiment, or HiRISE. Riding on NASA's Mars Reconnaissance Orbiter, HiRISE can resolve features on the surface down to one meter in size from its orbit 200 miles above Mars.

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