PASADENA, Calif. – A distant world gleaming in sunlight, Earth’s twin planet, Venus, shines like a bright beacon in images taken by NASA’s Cassini spacecraft in orbit around Saturn.
One special image of Venus and Saturn was taken last November when Cassini was placed in the shadow of Saturn. This allowed Cassini to look in the direction of the sun and Venus, and take a backlit image of Saturn and its rings in a particular viewing geometry called “high solar phase.” This observing position reveals details about the rings and Saturn’s atmosphere that cannot be seen in lower solar phase. (more…)
In a new analysis of thousands of U.S. women of childbearing age, Brown University researchers found that most exceeded the median blood level for two or more of three environmental pollutants that could harm brain development of fetuses and babies: lead, mercury, and polychlorinated biphenyls (PCBs).
PROVIDENCE, R.I. [Brown University] — Nearly 23 percent of American women of childbearing age met or exceeded the median blood levels for all three environmental chemical pollutants — lead, mercury, and PCBs — tracked in an analysis of data on thousands of women by Brown University researchers. All but 17.3 percent of the women aged 16 to 49 were at or above the median blood level for one or more of these chemicals, which are passed to fetuses through the placenta and to babies through breast milk. (more…)
Professor and students study how microbial life changes along the river
The mercury is pushing 100, but professor Michael Sadowsky and two assistants leave the indoor coolness for the bank of the Mississippi River as it flows by the University of Minnesota Twin Cities campus.
The three men send a bucket splashing into the current and haul back a water sample. That doesn’t affect the river much, but information locked away in bacteria from the sample may tell them a great deal about how the river’s microbial communities change along its course through Minnesota and how human activity affects them.(more…)
Astronomers report a baffling discovery never seen before: An extraordinary amount of dust around a nearby star has mysteriously disappeared.
“It’s like the classic magician’s trick — now you see it, now you don’t,” said Carl Melis, a postdoctoral scholar at UC San Diego and lead author of the research. “Only in this case, we’re talking about enough dust to fill an inner solar system, and it really is gone!”
“It’s as if the rings around Saturn had disappeared,” said co-author Benjamin Zuckerman, a UCLA professor of physics and astronomy. “This is even more shocking because the dusty disc of rocky debris was bigger and much more massive than Saturn’s rings. The disc around this star, if it were in our solar system, would have extended from the sun halfway out to Earth, near the orbit of Mercury.” (more…)
*The Event Horizon Telescope is an Earth-sized virtual telescope powerful enough to see all the way to the center of our Milky Way, where a supermassive black hole will allow astrophysicists to put Einstein’s Theory of General Relativity to the test.*
Astronomers, physicists and scientists from related fields across the world will convene in Tucson, Ariz. on Jan. 18 to discuss an endeavor that only a few years ago would have been regarded as nothing less than outrageous.
The conference is organized by Dimitrios Psaltis, an associate professor of astrophysics at the University of Arizona’s Steward Observatory, and Dan Marrone, an assistant professor of astronomy at Steward Observatory. (more…)
Humans pump thousands of tons of vapor from the metallic element mercury into the atmosphere each year, and it can remain suspended for long periods before being changed into a form that is easily removed from the atmosphere.
New research shows that the upper troposphere and lower stratosphere work to transform elemental mercury into oxidized mercury, which can easily be deposited into aquatic ecosystems and ultimately enter the food chain. (more…)
ANN ARBOR, Mich.— The solar wind sandblasts the surface of planet Mercury at its poles, according to new data from a University of Michigan instrument on board NASA’s MESSENGER spacecraft.
The sodium and oxygen particles the blistering solar wind kicks up are the primary components of Mercury’s wispy atmosphere, or “exosphere,” the new findings assert. Through interacting with the solar wind, they become charged in a mechanism that’s similar to the one that generates the Aurora Borealis on Earth. (more…)