Aku tahu tak akan selamanya bisa menikmati secangkir kopi di pagi hari bersamamu. Karena itu, untuk setiap pagi yang dapat dilewati meneguk kehangatan ini, aku sangat bersyukur :)
Strombus galeatus (Eastern pacific Giant Conch)
from: Kiener, L. C. (1843). Spécies général et iconographie des coquilles vivantes : comprenant la collection du Muséum d’histoire naturelle de Paris, la collection Lamarck, celle du Prince Masséna … et les déecouvertes réecentes des voyageurs / par L.-C. Kiener. Vol. 4, p. 153.
Asa inget lapak paleon….
On February 15 a chunk of rock about 50 meters wide will whiz by Earth at nearly 8 km/s, coming within 27,680 km of our planet’s surface — closer than many weather and communications satellites.
For those of you more comfortable with imperial units, that’s 165 feet wide traveling 17,800 mph coming within 17,200 miles. But regardless whether you prefer meters or miles, in astronomy that’s what’s called a close call.
Scientists stress that there’s no danger of an impact by this incoming asteroid, designated 2012-DA14, but it’s yet another reminder that in our neck of the Solar System we are definitely not alone.
“2012-DA14 will definitely not hit Earth,” says JPL’s near-Earth object specialist Don Yeomans. “The orbit of the asteroid is known well enough to rule out an impact.”
But with 2012-DA14′s upcoming February flyby Yeomans notes, “this is a record-setting close approach.”
The rocky asteroid will come within about 4 Earth radii, which is well within the orbits of geosynchronous satellites. During its closest approach at 19:26 UTC it should be visible in the sky to amateur telescopes (but not the naked eye), becoming as bright as an 7th- or 8th-magnitude star.
Radar observatories will be watching 2012-DA14 during the days leading up to and following its approach in an attempt to better determine its size, shape and trajectory. NASA’s Goldstone facility will have an eye — er, dish — on DA14, but it won’t be visible to Arecibo. Stay tuned for more info!
Read more about 2012-DA14 on the JPL Near-Earth Object Program page here.Credit: NASA/JPL,
The Mohs scale of mineral hardness characterizes the scratch resistance of various minerals through the ability of a harder material to scratch a softer material. It was created in 1812 by the German geologist and mineralogist Friedrich Mohs and is one of several definitions of hardness in materials science. The method of comparing hardness by seeing which minerals can scratch others, however, is of great antiquity, having first been mentioned by Theophrastus in his treatise On Stones, c. 300 BC, followed by Pliny the Elder in his Naturalis Historia, c. 77 AD.