Nov 15, 18 05:03 PM
heatwave kills more people than earthquakes
Nov 15, 18 05:02 PM
Mednews announcements of latest treatments, medicines and discoveries
Nov 14, 18 10:29 AM
cancer a fight we can win
If a fireball hits Earth, and nobody notices, is it still a news event?
The answer is yes, because scientists are increasingly tracking the space rocks and debris that enter Earth's atmosphere. The largest meteor since the 2013 impact in Chelyabinsk, Russia, hit Earth on Feb. 6, and NASA's meticulous Fireballs and Bolides Report has ensured the news went public eventually.
How did such a large object collide with Earth without attracting notice? The truth is that it happens much more frequently than many people might think. NASA tracks an average of 30 meteorite impacts annually, but since 70 percent of the planet's surface is largely uninhabited water, most go unnoticed, Brid-Aine Parnell reported for Forbes.
The Feb. 6 fireball fell into the ocean off the coast of Brazil and released energy roughly equivalent to 13,000 tons of TNT. This is significantly less than the Chelyabinsk impact, which injured more than 1,000 people with the equivalent of 500,000 tons of TNT, but it was at least 26 times as powerful as any of the three impacts NASA reported in February 2015.
Tracking the path of what NASA calls "near-Earth objects" is an uncertain science, but it has made progress in recent years. NASA set up the Planetary Defense Coordination Office in January and in doing so increased the budget for tracking asteroids and near-Earth objects to $50 million, up from $4 million in 2010, the first year Congress and the White House identified the project as a priority. NASA detects about 1,500 near-Earth objects each year, according to its website.
Despite this effort to track and warn the public, should a space rock's path hit land, scientists can still miss impacts. They failed to predict a fireball that exploded over Thailand in September because it was too small to attract attention, Lisa Suhay reported for The Christian Science Monitor.
"For sporadic fireball meteor events like this one, there is no warning sign,” Mike Hankey, American Meteor Society operations manager, told The Christian Science Monitor. “They happen too quickly. In the case of this meteor, since it happened during the day, it was traveling away from the sun, which would make it impossible to detect with telescopes."
Often what falls is not a meteor but rather a piece from an old satellite or space shuttle that has orbited the Earth for months and even years before falling, The Christian Science Monitor wrote:
Bits of space junk fall from the sky intermittently as an estimated 500,000 pieces of debris continues to clutter the area of "near space" around the Earth. Although space is vast and mostly empty, the "near space" immediately surrounding Earth is increasingly crowded. NASA tracks roughly 20,000 pieces of old or broken debris larger than a softball from satellites and missions past. . . .The US Air Force and NASA can only track the larger pieces, however, and tiny pebbles can also damage the International Space Station and orbiting vehicles.
Whether it is space debris or a space rock, the increasing level of monitoring ensures that even unnoticed objects receive some attention.
Indian authorities say a falling object that killed a bus driver and injured three others was a meteorite.
If proven, it would be the first such death in recorded history.
Experts said other explanations were possible for the incident Saturday in the southern state of Tamil Nadu.
The impact of the object left a large crater in the ground and shattered window panes in a nearby building, killing the driver who was walking past.
Images in local media showed a blueish rock, which Tamil Nadu's Chief Minister Jayalalithaa Jayaram described as a "meteorite" -- although scientists say this has not yet been proved.
"A meteorite fell at a private engineering college... and claimed the life of a college bus driver," said the chief minister in a statement late Sunday expressing "shock" at the news.
S. P. Rajaguru, assistant professor at the Indian Astrophysics Institute in Bangalore, said the rock could be a meteorite but further tests were needed.
If proven it would be the first meteorite death of a human in recorded history, he said.
"Most of the meteors never reach the earth surface as they completely vaporise in the atmosphere," he told AFP by phone.
Feb 5th 2016
An asteroid as long as a basketball court will give Earth a close shave next month — though scientists aren't sure just how close.
The near-Earth asteroid 2013 TX68, which is thought to be about 100 feet (30 meters) in diameter, will zoom past our planet on March 5.
The space rock could come as close as 11,000 miles (17,700 kilometers) — less than 5 percent of the distance from Earth to the moon — or stay up to 9 million miles (14.5 million km) away during the flyby, NASA officials said.
"The variation in possible closest-approach distances is due to the wide range of possible trajectories for this object, since it was tracked for only a short time after discovery," NASA officials wrote in a statement Wednesday (Feb. 3).
There is no danger that 2013 TX68, which was first spotted in October 2013, will collide with Earth on this pass, researchers said. However, there is an extremely slight chance — less than 1 in 250 million — of an impact on Sept. 28, 2017, and even lower odds during flybys in 2046 and 2097.
"The possibilities of collision on any of the three future flyby dates are far too small to be of any real concern," Paul Chodas, manager of the Center for NEO Studies at NASA's Jet Propulsion Laboratory in Pasadena, California, said in the same statement. "I fully expect any future observations to reduce the probability even more."
Just two years ago, 2013 TX68 flew by Earth, at a distance of 1.3 million miles (2 million km).
Scientists think the near-Earth object that exploded over the Russian city of Chelyabinsk in February, damaging buildings and injuring more than 1,000 people, measured about 65 feet (20 m) across.If 2013 TX68 or another asteroid of its size were to slam into Earth, it would probably explode in an airburst about twice as energetic as the Chelyabinsk event, NASA officials said.
The above illustration shows the damage caused by an asteroid collision on Jupiter a few years ago.
Although the chances are about one in a million,such a collision with Earth, providing it doesn’t do any damage can turn out to be a very fortunate incident if it lands on your property, there are other people that are very interested in the material itself and apart from the scientists some people have collections of a such specimens and even small pieces , and they are quite prepared to pay considerable sums of money for these rare specimens.
And the warnings are, take care they’re usually quite hot and should be checked by experts for radioactive decay, once it is cooled and checked the other thing is don’t forget to protect it from theft they can be quite valuable.
The definition of these bodies is that they are small, rocky solar system bodies that populate interplanetary space out by the orbit of Jupiter; they are also referred to as minor planets or planetoids. They are rich in precious metals and other metals that some people, especially scientists, are quite prepared to pay considerable sums of money for, these very rare specimens. This page will provide information on what you need to know about asteroids.
In the earth as early history they rained down by the millions and contributed to the formation of the earth as we know it today, they are also thought to have been responsible for the extinction of the dinosaurs.
Today’s collisions are usually quite small and most of them burn up in our protective atmosphere, occasionally they do make contact with the earth and a notable example was one that was thought to have exploded over a forest in Russia causing a blast wave that knocked down trees over many miles.
At 7:14 a.m. on June 30, 1908 Trees were knocked down over hundreds of square km by the Tunguska gigantic impact. scientists still do not know what caused this explosion
Some of these bodies are very large and if they collided with the earth would do a colossal amount of damage, the authorities’ can now monitor the orbits of the larger specimens and are making plans to destroy or divert them from their collision path with our planet.
The likelihood of such a collision is very small and not really worth getting worried about.
There is only one recorded event where one actually struck a human being, after crashing through the building and losing most of its momentum it struck a woman a glancing blow on the thigh causing just a minor injury.
If it lands to your property you should be careful as they’re usually quite hot and should be checked by experts for radioactive decay.
There are billions of asteroids in the solar system and they are grouped together into the four main groups, known as the Main belt, Kuiper belt, Trojans, and the Scattered disc.
Fortunately with modern communication systems these dangerous situations can be monitored easily and warnings issued by local government, civil defense, police, local radio and television.Home Page - other - asteroid