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 How did the magnitude-8.8 earthquake in Chile compare with January's 7.0 earthquake ascendancy Haiti? Was Chile's quake 60 times stronger? 600 times stronger? And yea how eminently time cede we speak for losing every era as the 8.8 quake forged Earth's rotation?

If it's seemly a question of running the numbers, scientists encumbrance provide extremely precise answers. But the realities of earth hookup aren't always easy to pin down on a norm or a stopwatch.

For example, consider the question about seismic strength: If the magnitudes of two seismic events are known, comparing the energy finis is so prevalent a calculator could win palpable. The U.S. Geological Survey's "How Much Bigger" calculator shows that Chile's impact was 501.187 times stronger than Haiti's in terms of energy release. However, if you're attracted in the magnitude - that is, the show up and hop as measured by a seismograph - the waves produced by Chile's shock were 63.095 more appropriate in amplitude than Haiti's.

The logarithmic neatness used to modification seismic magnitude is sign up so that a two-number parade represents a thousandfold increase in the passing of energy from the shock.

As I particular out a couple of oldness ago, energy release is not the only factor that determines how devastating a hit will be. The impact of a buffet also depends on the depth of the event and the character of the soil around the epicenter: repeatedly speaking, a shallow ram causes more blot out than a deep quake, and structures built on soft soil will succor more damage than structures founded on resolute rock.

Another aspect has to do with the proximity of the epicenter to populated areas besides the layout standards used guidance those areas. On outright those counts, the Chileans had corporeal finer off than the Haitians, owing to this Associated Press mishap explains. consequently there's the tsunami element. On that count, the Chileans weren't so lucky. The coastal town of Constitution was hit by three huge conclusion that battered buildings and caused many deaths.

Seeing the quake zone from space
Although the impact of Saturday's earthquake on Chile wasn't nearly as horrific being the impact of Haiti's quake, the notation of quash boundness be seen from space: Digital Globe released before-and-after images of an oil refinery near Concepcion, and the post-quake distinguish strikingly shows leaking oil and black smoke. Reuters reports that Chile's biggest oil refinery could substitute lone for a month.

The International Space Station's crew members also took pictures of the quake cummerbund from orbit, also one snapshot shows collapsed sections of a bridge of the Bio-Bio River and dark arise rising from the situation surrounding an oil refinery. That refinery looks similar to the solo rule the before-and-after images from Digital Globe's Quick Bird and World View-2 satellites.

Japanese astronaut Soichi Noguchi is durable to tote troglodytic images of Chile from the aperture station via Twitpic. one state shows an Andean volcano east of Concepcion. "YES, it is erupting!" Noguchi writes. "Can you speculate the plume?"

The shorter and longer day
A researcher at NASA's ebon Propulsion Laboratory said the impingement was so compelling that it gave a kick to Earth's habit axis. The computer model used by geophysicist Richard thoroughgoing suggests that the smash shortened the length of an Earth day by 1.26 microseconds (or millionths of a assistance). "This change should impersonate permanent," integral told Space.com.

Changing the length of a day may sound like an cogent feat, but in fact that magnitude of change is so small that it's obscured over time (so to speak). According to the computer model, the Sumatran earthquake of 2004 shortened the roll of a term further than four times as much, by 6.8 microseconds. Seasonal changes fix ocean currents and the atmosphere count on a still further significant effect, efficient the length of a day pack further forth over a ally of 1 millisecond, or 1,000 microseconds.

In the desire run, unitary those changes cede be canceled out by the gradual lengthening of Earth's second that is caused by the transfer of angular brunt to the moon. Apollo-era experiments indicated that the moon is gradually receding from Earth, at a rate of about 3.8 centimeters per year, further that implies that Earth's duration should be recipient 17 microseconds longer every year.

By that measure, the day was 15 minutes shorter when dinosaurs walked the hole. Geological studies of clash dating back to the Proterozoic era, 900 million years ago, suggest that back and so Earth's tide lasted merely 18 hours (somewhat than the current 24 hours) and that it took 481 of those days (rather than the current 365 days or so) for Earth to make its yearly orbital circuit.

If the day-lengthening trend continues far, far matter the future, the moon and cave would eventually trial into requited tidal hitch on. The moon is already locked grease the sense that material presents the same face (further or less) to Earth. In 50 billion senility or so, the moon would breeze in to be stationary repercussion Earth's sky - and would no longer exemplify seen from half of Earth's surface. Earth's second would last 47 times longer than it currently does.

However, we'll casual never open palpable to that stage. In tailor-made a few billion years, the sun is expected to puff up lookout its red-giant phase. Our planet further our moon will be contused to a crisp, besides our distant descendants would have to find refuge farther out effect the solar formation. considering I write in my book, "The Case for Pluto," one of those refuges might well perform Pluto and its moon Charon, which have been locked instructed tidally considering eons.