In 1913, astronomer Vesto Slipher—who, despite his exotic-sounding name, was from Mulberry, Indiana—was studying the light of spiraling nebulae (what were later discovered to be galaxies). He knew that, as celestial objects move away from us, their light gets stretched out, causing it to shift to a different section of the color spectrum– toward the red end. In this phenomenon, called redshift, the appearance of the light depends on the observer and the observed: a celestial object’s light appears redshifted to us, on Earth, because it is moving away from us.

But what wasn’t known—and what astronomers later found out—was that it was not only the movement of galaxies away from us that causes redshift. The universe’s effect on light waves as they thread their way through the cosmos is important as well. The path those galaxies’ light takes to reach us—perhaps as we’re standing in a quiet field in Indiana, the only interruption of light a few lamps from a small town—cannot avoid the pull of our expanding universe.

To picture light waves, think of water shooting out of a garden hose. The water that first comes out of the hose, depending on the force of the stream, lands several feet away from the hose’s mouth. For the moment, ignore the idea of gravity, so your line of water never hits the ground; it just persists as a continuous stream of hydrogen-oxygen molecules.

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Fifty years before the term “carbon footprint” came in vogue, MIT held a symposium titled “Space Heating with Solar Energy.” Three women were on the 98-person registration list.

Scientists at the August 1950 gathering warned of dire situations familiar to us today. Eugene Ayres, a solar expert with the Gulf Research and Development Company, wrote in his paper’s abstract, “We know that time will come when we shall require a consciously engineered plan for solar energy utilization instead of simply burning up everything we can burn as rapidly as we can find and produce it.” He went on to outline the peak of the United States’s coal production, forecast oil being depleted within a century, and noted the possibility of having to import our fuel needs from abroad.

Embedded in this conference was another revolution: the opening of the field to women. Clippings from newspapers covering the event point to the persons who most captured the public’s interest: the “woman scientist” and “woman architect” who built the Dover House, a $10,000 house heated entirely by the sun. The scientist and the architect were Maria Telkes, an MIT researcher in the department of metallurgy, and Eleanor Raymond, who was based in Boston. Full Article »

Electric vehicles that use electric power and gasoline separately have thrown a wrench into the EPA’s fuel-rating system.

The Volt, belonging to a new class of vehicles called “extended-range electric vehicles,” operates on electric power for up to forty miles, says Stanley Sullivan, an engineer at a large automobile manufacturing company. After the initial charge of the battery has been depleted, a gas engine kicks in to recharge the battery. Because the power sources of electric vehicles are different—your home electrical outlet and a gas engine—assessing their miles-per-gallon (MPG) rating will be difficult.

Sullivan points out that the EPA will have to handle electric vehicles differently than a typical hybrid like Toyota’s Prius. A hybrid like the Prius runs on its lithium-ion battery up to a speed of 42 miles per hour, after which the gas engine helps propel the vehicle. A vehicle like the Volt, on the other hand, can drive up to 75 mph and up to 40 miles before its gas engine kicks in—but not to propel the vehicle. Instead, it recharges the battery. This is why General Motors was able to quote a rating of 230 MPG for the Volt in August 2009.

Because the Volt is a new kind of vehicle, the EPA cannot describe its efficiency in the same way it rates a conventional car’s efficiency. But the organization will have to release this information before the Volt is slated to hit the market—sometime in 2010, according to GM’s website. Full Article »

Fifty years before the term “carbon footprint” came in vogue, MIT held a symposium titled “Space Heating with Solar Energy.” Three women were on the 98-person registration list.

Scientists at the August 1950 gathering warned of dire situations familiar to us today. Eugene Ayres, a solar expert with the Gulf Research and Development Company, wrote in his paper’s abstract, “We know that time will come when we shall require a consciously engineered plan for solar energy utilization instead of simply burning up everything we can burn as rapidly as we can find and produce it.” He went on to outline the peak of the United States’s coal production, forecast oil being depleted within a century, and noted the possibility of having to import our fuel needs from abroad.

Embedded in this conference was another revolution: the opening of the field to women. Clippings from newspapers covering the event point to the persons who most captured the public’s interest: the “woman scientist” and “woman architect” who built the Dover House, a $10,000 house heated entirely by the sun. The scientist and the architect were Maria Telkes, an MIT researcher in the department of metallurgy, and Eleanor Raymond, who was based in Boston. Full Article »

Science fiction gets another chance to get it all wrong.

A study using the Canada-France-Hawaii telescope based in Hawaii confirmed that as the Andromeda galaxy moves through our local cosmic neighborhood, it eats everything in its path—including, eventually, us.

Andromeda grows by pulling galactic companions to it, like spare change down a sewer grate. The astronomers found evidence of this interaction by detecting stars streaming off some dwarf galaxies not fully absorbed by Andromeda. The shape of these streams traces the size and history of the galaxies being pulled in, says MIT astrophysicist Robert Simcoe, and is determined by the mass of the galaxy itself: the larger the galaxy being eaten, the closer the stream will be to its center.

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