2017-8-14 : Asteroid to shave past Earth on Oct 12: ESA By Mariette Le Roux Paris

A house-sized asteroid will shave past our planet on October 12, far inside the Moon’s orbit but without posing any threat, astronomers said Thursday.  The space rock will zoom by harmlessly at a distance of about 44,000 kilometres (27,300 miles) — an eighth of the distance from the Earth to the Moon, according to the European Space Agency. This is just far enough to miss our geostationary satellites orbiting at about 36,000 kilometres.

“We know for sure that there is no possibility for this object to hit the Earth,” Detlef Koschny of ESA’s “Near Earth Objects” research team told AFP. There is no danger whatsoever.”

The asteroid, dubbed 2012 TC4, first flitted past our planet in October 2012 — at about double the distance — before disappearing from view.  It is about 15-30 metres (49-98 feet) long, and was travelling at a speed of some 14 kilometres (nine miles) per second when spotted.  Scientists expected the asteroid to return for a near-Earth rendezvous this year, but did not know how close it would get.  Now, the Very Large Telescope of the European Southern Observatory (ESO) in Chile has managed to track the rock down, some 56 million kilometres away, and determine its trajectory.

“It’s damn close,” said Rolf Densing, who heads the European Space Operations Centre in Darmstadt, Germany. “The farthest satellites are 36,000 kilometres out, so this is indeed a close miss,” he told AFP.

For researchers, the near miss will provide a rare chance to test Earth’s “planetary defence” systems — which at this point are focused on early warning rather than active asteroid deflection.

Observing TC4’s movements “is an excellent opportunity to test the international ability to detect and track near-Earth objects and assess our ability to respond together to a real asteroid threat,” said an ESA statement.  Asteroids are rocky bodies left over from the formation of our solar system some 4.5 billion years ago.  There are thought to be millions of them, most of them in a “belt” between the orbits of Mars and Jupiter.

A space rock slightly bigger than TC4, at 40 metres, caused the largest Earth impact in recent history when it exploded over Tunguska, Siberia, in 1908.

In 2013, a meteoroid of about 20 metres exploded in the atmosphere over the city of Chelyabinsk in central Russia with the kinetic energy of about 30 Hiroshima atom bombs.

The resulting shockwave blew out the windows of nearly 5,000 buildings and injured more than 1,200 people. It caught everyone unawares.

If an object the size of TC4 were to enter Earth’s atmosphere, “it would have a similar effect to the Chelyabinsk event,” said the ESA.

But Earth’s atmosphere stretches only a few hundred kilometres far, and TC4 will comfortably miss it. Also, it would likely behave very differently to the Chelyabinsk object.

“The Chelyabinsk meteoroid was a piece of comet and they are usually made of icy material,” said Densing. “Due to the icy nature it probably dissipated in the atmosphere… When we’re talking about asteroids, this is solid material. They are mostly made up of iron, so will not so easily dissipate their energy in the atmosphere.”

TC4 is unlikely to shed any debris into the atmosphere.

Even if it did, no evacuation would be required for an object this size, said Koschny, merely a warning for people to stay away from windows that could shatter from the shockwave.

Densing, who has previously warned that humanity is not ready to defend itself against an Earth-bound object, said he would not lose any sleep, not over this one.  “However, it makes you wonder what will happen next time,” he said.  “I would have felt a bit more comfortable if we… had a longer pre-warning time.”

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2017-8-7 : Meteor Echoes Live Stream: livemeteors.com

When a meteor enters the Earth’s upper atmosphere it excites the air molecules, producing a streak of light and leaving a trail of ionization (an elongated paraboloid) behind it tens of kilometers long. This ionized trail may persist for less than 1 second up to several minutes, occasionally. Occurring at heights of about 85 to 105 km (50-65 miles), this trail is capable of reflecting radio waves from transmitters located on the ground, similar to light reflecting from a mirrored surface. Meteor radio wave reflections are also called meteor echoes, or pings.

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2017-8-5 : REPORTING SIGHTINGS

Reporting Sightings

Please capture sighting on video as quickly as you can possibly react.

General Guidance

A fireball is another term for a very bright meteor, generally brighter than magnitude -4, which is about the same magnitude of the planet Venus as seen in the morning or evening sky. A bolide is a special type of fireball which explodes in a bright terminal flash at its end, often with visible fragmentation.

If you happen to see one of these memorable events, we would ask that you report it here to the American Meteor Society, remembering as many details as possible. This will include things such as brightness, length across the sky, color, and duration (how long did it last), it is most helpful of the observer will mentally note the beginning and end points of the fireball with regard to background star constellations, or compass direction and angular elevation above the horizon.

Individual reports are shared with other interested organizations, and saved for statistical study purposes. Reports are also shared with the general public in the form of our Fireball Sightings Log, which allows visitors to monitor the fireball activity which is reported to us from across North America, over the course of a given year. Although the AMS does not pursue fireball reports with the intent of recovering meteorites, we do notify relevant planetary scientists when promising events occur in their local geographic areas, for them to pursue as they wish.

https://mufoncms.com/cgi-bin/report_handler.pl

Extra Canadian Reporting

Check : http://www.skyscan.ca/fireballs.htm

Feel free to phone at reasonable hours : 250-598-6692 in Victoria, BC