Ed White performs first U.S. spacewalk
Astronaut Edward H. White II, pilot for the Gemini-Titan 4 space flight, floats in space during America’s first spacewalk.
Morning, Moon, and Mercury
Last week Mercury wandered far to the west of the Sun. As the solar system’s innermost planet neared its greatest elongation or greatest angle from the Sun (for this apparition about 27 degrees) it was joined by an old crescent Moon. The conjunction was an engaging sight for early morning risers in the southern hemisphere. There the pair rose together in predawn skies, climbing high above the horizon along a steeply inclined ecliptic plane. This well composed sequence captures the rising Moon and Mercury above the city lights of Brisbane in Queensland, Australia. A stack of digital images, it consists of an exposure made every 3 minutes beginning at 4:15 am local time on April 19. Mercury’s track is at the far right, separated from the Moon’s path by about 8 degrees.
Scientists are planning to use NASA’s Hubble Space Telescope to observe next month’s historic transit of Venus across the sun’s face.
But there’s a twist. Researchers can’t point Hubble anywhere near the sun, because our star’s bright light could damage the telescope’s super-sensitive instruments. So Hubble will watch the June 5-6Venus transit by using the moon as a mirror.
Imaged Above: Michael Wilce of Central London, UK took 20 composite shots to create this image of Venus transit on June 8, 2004. CREDIT: Michael Wilce
Four dead planetary systems, each lit by the burned-out core of a star that once resembled the sun, provide a harrowing forecast for Earth’s eventual demise.
Astronomers used the space-based Hubble telescope to probe the chemical signatures of dusty disks encircling the four star systems. In each they found a surprising abundance of elements that make up about 93 percent of Earth’s mass.
“What we are seeing today in these white dwarfs several hundred light years away could well be a snapshot of the very distant future of the Earth,” said Boris Gänsicke, an astrophysicist at the University of Warwick, in a press release.
Images: Three panels illustrate the death sequence of a planetary system. Four terrestrial planets orbit a sun-like star (top); the host star turns into a red giant and mixes up planetary orbits, causing them to collide (middle); dusty debris and asteroid-like objects are all that remains around the star, now a white dwarf (bottom). (Copyright of Mark A. Garlick/University of Warwick) [high resolution]
1. RINGS FROM AFAR
Measuring 175,000 miles wide but as little as 30 feet thick, Saturn’s rings contain debris of varying ages and composition, all revolving at different speeds.
2. THREE MOONS
Titan and Dione, along with speck-sized Prometheus appear in rare alignment. Tiny so-called shepherd moons help shape the rings and prevent them from dispersing.
Concentric rings wind in front of Satrun’s biggest moon, Titan, with tiny Janus in teh foreground. The rings are so massive that they have their own atmosphere, separate from Saturn’s. Cassini found evidence of oxygen all around the icy rings.
4. RINGS CLOSE UP
Xi(b)* a “brick in the wall” for solving how matter’s made, expert says.
An atom-smashing experiment at the Large Hadron Collider (LHC) has detected a new subatomic particle—and it’s a beauty.
Known as Xi(b)* (pronounced “csai bee-star”), the new particle is a baryon, a type of matter made up of three even smaller pieces called quarks. Protons and neutrons, which make up the nuclei of atoms, are also baryons.
The Xi(b)* particle belongs to the so-called beauty baryons, particles that all contain a bottom quark, also known as a beauty quark.
The newfound particle had long been predicted by theory but had never been observed. Although finding Xi(b)* wasn’t exactly a surprise, the discovery should help scientists solve the larger puzzle of how matter is formed.
Herr Wehrli has a knack for this; if you like that sky cleaning routine, you should see what he does with alphabet soup, a conifer twig, and a grassy field with sunbathers. He has these pictures, and more, in his books, including The Art of Tidying Up. I gotta say, I dig this guy’s sense of humor.
Pictures credit: Urs Wehrli. Tip o’ the dust pail to Lawrence Cuthbert, via Jeannie Jeannie.
Into the Sword of Orion
Distance: 1500 Light Years
Image Copyright Robert Gendler 2006
The region of Orion and Monoceros has unique importance as one of the great regions of active star formation in our galaxy.
Its proximity and favorable position in the sky have made this one of the most extensively studied regions in the Milky Way.
Sifting through Dust near Orion’s Belt
A new image of the region surrounding the reflection nebula Messier 78, just to the north of Orion’s Belt, shows clouds of cosmic dust threaded through the nebula like a string of pearls. The observations, made with the Atacama Pathfinder Experiment (APEX) telescope, use the heat glow of interstellar dust grains to show astronomers where new stars are being formed.
Meerab Atiq won the grand prize in the 3rd-5th grade category and attends Beaconhouse School System in Lahore, Pakistan. Meerab also won 1st place in the 3rd-5th grade painting category.Credit: Space Foundation
20 Things You Didn’t Know About Water
1 Water is everywhere—there are 332,500,000 cubic miles of it on the earth’s surface. But less than 1 percent of it is fresh and accessible, even when you include bottled water.
2 And “fresh” can be a relative term. Before 2009, federal regulators did not require water bottlers to remove E. coli.
3 Actually, E. coli doesn’t sound so bad. In 1999 the Natural Resources Defense Council found that one brand of spring water came from a well in an industrial parking lot near a hazardous waste dump.
4 Cheers! The new Water Recovery System on the International Space Station recycles 93 percent of astronauts’ perspiration and urine, turning it back into drinking water.
5 Kurdish villages in northern Iraq are using a portable version of the NASA system to purify water from streams and rivers, courtesy of the relief group Concern for Kids.
6 Ice is a lattice of tetrahedrally bonded molecules that contain a lot of empty space. That’s why it floats.
7 Even after ice melts, some of those tetrahedrons almost always remain, like tiny ice cubes 100 molecules wide. So every glass of water, no matter what its temperature, comes on the rocks.
8 You can make your own water by mixing hydrogen and oxygen in a container and adding a spark. Unfortunately, that is the formula that helped destroy the Hindenburg.
9 Scientists have a less explosive recipe for extracting energy from hydrogen and oxygen. Strip away electrons from some hydrogen molecules, add oxygen molecules with too many electrons, and bingo! You get an electric current. That’s what happens in a fuel cell.
10 Good gardeners know not to water plants during the day. Droplets clinging to the leaves can act as little magnifying glasses, focusing sunlight and causing the plants to burn.
11 Hair on your skin can hold water droplets too. A hairy leg may get sunburned more quickly than a shaved one.
12 Vicious cycle: Water in the stratosphere contributes to the current warming of the earth’s atmosphere. That in turn may increase the severity of tropical cyclones, which throw more water into the stratosphere. That’s the theory, anyway.
13 The slower rate of warming in the past decade might be due to a 10 percent drop in stratospheric water. Cause: unknown.
14 Although many doctors tell patients to drink eight glasses of water a day, there is no scientific evidence to support this advice.
15 The misinformation might have come from a 1945 report recommending that Americans consume about “1 milliliter of water for each calorie of food,” which amounts to 8 or 10 cups a day. But the report added that much of that water comes from food—a nuance many people apparently missed.
16 Call waterholics anonymous: Drinking significantly more water than is needed can cause “water intoxication” and lead to fatal cerebral and pulmonary edema. Amateur marathon runners have died this way.
17 Scientists at Oregon State University have identified vast reservoirs of water beneath the ocean floor. In fact, there may be more water under the oceans than in them.
18 Without water, ocean crust would not sink back into the earth’s mantle. There would be no plate tectonics, and our planet would probably be a lot like Venus: hellish and inert.
19 At the other end of the wetness scale, planet GJ 1214b, which orbits a red dwarf star, may be almost entirely water.
20 Recent evidence suggests that when the solar system formed 4.5 billion years ago, comets had liquid cores. If so, life may have started in a comet.