December 17, 2011
The photo above shows a collection of tektites -- a California slender salamander was added for purposes of scale. Tektites are natural glass. Several theories exist that explain their origin. Some scientists believed that tektites came from ancient lunar volcanoes, or were ejected by asteroid or meteorite impacts with the Moon. Others believed their origin is from outside the Earth-Moon system. The latest theory proposes that tektites were created from asteroid or meteorite impacts of the Earth. Tektite shapes may be irregular or rounded. As shown above are a teardrop, a dumbbell and a very small bowl shaped tektite. The bowl shaped tektite is known as australite (Australian tektites). No craters have been found associated with australites. It's been speculated that australites ended up in Australia after a huge meteorite impact in Asia or even in Antarctica. Such an impact would have ejected myriad rock fragments out beyond the Earth's atmosphere. These fragments perhaps then acquired their aerodynamic shape as they re-entered the atmosphere at a high velocity and in a molten stage.
Photo details: Camera Maker: OLYMPUS IMAGING CORP.; Camera Model: u1050SW,S1050SW; Focal Length: 9.1mm (35mm equivalent: 51mm); Aperture: f/4.0; Exposure Time: 0.020 s (1/50); ISO equiv: 80; Exposure Bias: +0.70 EV; Metering Mode: Matrix; Exposure: Creative Program (based towards depth of field); Exposure Mode: Manual; White Balance: Auto; Light Source: Unknown; Flash Fired: No (enforced); Orientation: Normal; Color Space: sRGB; Software: Adobe Photoshop CS3 Windows.