Fireballs
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Fireball

Rare asteroid discovered along the orbit of Uranus

Ken Croswell
New Scientist
Thu, 16 Feb 2017 18:58 UTC
Asteroid orbiting Uranus
© NASA/Erich Karkoschka (Univ. Arizona)Now with added Trojans.
A rare Trojan asteroid of Uranus has been found, following the same orbit as the planet. Its existence implies there could be many more of these companion asteroids, and that they are more common than we thought.

A Trojan asteroid orbits the sun 60 degrees ahead of or behind a planet. Jupiter and Neptune have numerous Trojans, many of which have been in place for billions of years. These primordial rocks hold information about the solar system's birth, and NASA has just announced plans to visit several of them in the 2020s and 2030s.

But Saturn and Uranus live in a rougher neighbourhood: the giant planets on either side of them yank Trojans away through their gravitational pull. So Saturn has no known Trojan, and Uranus had only one.

In July, though, astronomers reported a new asteroid, named 2014 YX49, that shares Uranus's orbital period of 84 years. Now computer simulations of the solar system by brothers Carlos and Raul de la Fuente Marcos at the Complutense University of Madrid, Spain, indicate the asteroid is a Uranus Trojan. The simulations show that the asteroid has maintained its position ahead of Uranus for thousands of years.

"It is bigger, probably twice as big as the first one," says Carlos. The new asteroid is brighter than the first, but its exact size depends on how much light its surface reflects. If it reflects half the sunlight striking it, it's 40 kilometres across; if it reflects 5 per cent, its diameter is 120 kilometres.
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Fireball

Valentine's Day meteor fireball spotted over Eastern US


The American Meteor Society
Thu, 16 Feb 2017 18:48 UTC
Meteor Over Eastern US
© Chris Wolf/AMSAMS Event#614-2017 – screeenshot of a video shared by Chris Wolf on the AMS Website.
53 reports from Pennsylvania, Connecticut, New Jersey, New York and Maryland

The AMS has received 63 reports so far about of a fireball event over seen over Pennsylvania on Tuesday, February 14th 2017 around 08:32pm EST (Feb 15th - 01:39 UT.). The fireball was seen primarily from Pennsylvania but witnesses from Connecticut, New Jersey, New York, and Maryland also reported the event. Some witnesses described the meteor as orange, yellow and white. After a fairly extensive investigation, we came to the conclusion that it wasn't Cupidon but a bright meteor.

First Estimated Trajectory

The map below shows the witnesses location with the first estimated trajectory. The preliminary estimated trajectory plotted from the witness reports shows the meteor was traveling from the West to the East and ended its flight somewhere over Scranton, PA.
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Meteor

Mystery object (possibly a meteorite) lands in UK garden after loud thump in middle of night

Saiqa Chaudhari
Bury Times
Thu, 09 Feb 2017 06:22 UTC
meteorite falls england
© Bury Times
This mysterious rock like object is causing quite a stir in Lowercroft.

Now the couple in whose garden it was found are hoping someone may be able to shed some light on what it is — and where it came from.

Pauline and Norman Pollard were baffled to discover the striking black and yellow material in their garden, just days after hearing a loud noise.

Initially the couple thought it may be a meteorite - and don't know whether the noise is related to the find.

Mr Pollard, who lives in Lowercroft Road, aged 74, said: "We found it in the garden after we had heard a loud bang or thump in the middle of the night, it was like a car door banging."
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Info

Cause of noises made by meteors found

Ross Pomeroy
Real Clear Science
Mon, 06 Feb 2017 04:46 UTC
Fireball Sound
© Spalding et. al./Scientific Reports
Bright, flaring meteors are sometimes accompanied by faint noises. What's strange about these popping, sizzling, rustling, and hissing sounds are that they reportedly occur almost instantly to earthly onlookers. This makes little sense, as meteors are as far as sixty miles away from viewers on the ground, so any sound they make should take several minutes be heard. What's going on? Do meteors somehow defy the laws of physics?

Researcher Richard Spalding and several of his colleagues at Sandia National Laboratories recently set out to study this strange phenomenon, and in a study just published to the journal Scientific Reports, they announce that the sounds are likely created through light.

Meteor fireballs sometimes pulse with light many times brighter than the full Moon, and these blasts can briefly heat the surfaces of objects many miles away. Such sudden temperature changes can actually create sound.

"We suggest that each pulse of light can heat the surfaces of natural dielectric transducers," Spalding and his colleagues write. "The surfaces rapidly warm and conduct heat into the nearby air, generating pressure waves. A succession of light-pulse-produced pressure waves can then manifest as sound to a nearby observer."
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Fireball 4

Bright green meteor fireball illuminates skies over Wisconsin and Illinois

Vincent Perlerin
American Meteor Society
Mon, 06 Feb 2017 08:51 UTC
meteor fireball over Lisle
© American Meteor SocietyAMS Event#454-2017 – Caught on a Police Dashcam (Lisle, IL PD)
Over 170 reports from IL, WI, MI, IN, OH, IA, NY, Ontario, KY and MN

The AMS has received over 170 reports so far (and counting...) about of a fireball event over seen over Wisconsin on Wednesday, February 6th 2017 around 01:27CST (07:31 UT.). The green fireball was seen primarily from Illinois and Wisconsin but witnesses from Michigan, Indiana, Ohio, Iowa, New York, Kentucky, Minessota and Ontario (Canada) also reported the event.

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Comet 2

Comet 45P approaches Earth - Closest approach on Feb. 11th


Space Weather
Mon, 06 Feb 2017 06:01 UTC
45P Honda-Mrkos-Pajdusakova
© Michael Jäger
A small comet named "45P/Honda-Mrkos-Pajdusakova" (45P for short) is approaching Earth. At closest approach on Feb. 11th, the comet will be 7.4 million miles from our planet, visible in binoculars and small telescopes. This is what it looks like (image on the left).

Michael Jäger of Stixendorf, Austria, took the picture on Dec. 31, 2016, just as the comet was swinging around the sun en route to Earth. Since then 45P's icy nucleus has been heated by solar radiation, causing it to spew brightening jets of gas into the comet's green atmosphere. Why green? Because the comet's vaporizing nucleus emits diatomic carbon, C2, a gas which glows green in the near-vacuum of space.

According to the Minor Planet Center, this is the 8th closest pass of any comet in the modern era (since ~1950, when modern technology started being used to study comets). It will only be 31 times farther from Earth than the Moon.

Interestingly, 45P made an even closer approach on its previous orbit (23 lunar distances), so it is also on the list as the 5th closest.

Proximity makes the comet bright despite its small size. Forecasters say 45P could be on the verge of naked eye visibility (6th magnitude) when it emerges into the pre-dawn sky later this week. The best time to look is during the dark hours before sunrise between Feb 9th and 12th. The comet will be racing through the constellation Hercules high in the eastern sky. Sky maps: Feb. 9, 10, 11, 12.

Got a great picture? First, submit it to Spaceweather.com. Next, send it to the Planetary Science Institute, which is collecting amateur images to help professional researchers study Comet 45P. More resources: 3D Orbit, Ephemeris.
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Fireball 5

Bright meteor fireball captured over Caeté, Minas Gerais, Brazil

Exoss Citizen Science
YouTube
Tue, 31 Jan 2017 13:16 UTC
Fireball over Caete, Brazil
© Via Twitter@Rainmaker1973
Bright fireball captured over Caeté, Minas Gerais, Brazil on January 30, 2017.

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Fireball 2

Asteroid attack? Yet another asteroid to give Earth a close shave

Eric Mack
CNET
Wed, 01 Feb 2017 13:46 UTC
Another close shave
© ESASpace rock block party!
For the fourth time since the start of 2017, a small celestial body will pass closer to Earth than the distance between us and the moon. Recently discovered asteroid 2017 BS32 zips by around midday Thursday.

This latest narrow shave comes just a few days after the closest such flyby in months, prompting observers and some astronomers to wonder if the apparent blitz of tiny planetoids could be more than mere coincidence.

According to astronomer Paul Cox at the Slooh observatory, the apparent bursts of small, close-approaching asteroids were first spotted just before buzzing us initially sparked discussion in 2016.

"One possibility sprang to mind -- that these clusters of smaller asteroids making close approaches to Earth over relatively short periods of time were in fact the fragments from larger asteroids that had broken up," Cox said via email. "However, when we reviewed the orbits of each of the asteroids, we found no correlation between them -- showing clearly they weren't associated in any way."

Cox said the scientists also looked for a connection to seasonal changes or to weather at observatories that might reduce discoveries of nearby asteroids, but there was no conclusive data to be found.
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Binoculars

Close encounter! Asteroid discovered yesterday whizzed 70,000 km from Earth

Gianluca Masi
Virtual Telescope
Mon, 30 Jan 2017 01:36 UTC
NEO 2017 BH30
The near-Earth asteroid 2017 BH30 was discovered by the Catalina Sky Survey in Arizona (USA) on 29 January 2017 and announced later the same day by the Minor Planet Center: it was going to have a very close encounter with the Earth, at 0.18 lunar distances (about 70.000 km).

At Virtual Telescope Project we captured 2017 BH30 while it was safely approaching us. Above is an image coming from the average of two 60-seconds exposures, remotely taken with "Elena" (PlaneWave 17″+Paramount ME+SBIG STL-6303E robotic unit) available at Virtual Telescope. The robotic mount tracked the fast (36″/minute) apparent motion of the asteroid, so stars are trailing. The asteroid is perfectly tracked: it is the sharp dot in the center, marked with two white segments.

To get these impressive results, the Paramount ME robotic mount tracked using the ephemerides retrieved via the JPL's Horizon webserver. At the imaging time, asteroid 2017 BH30 was at about 500.000 km from us and safely approaching. Its diameter should be around 5-10 meters or so.

The observations provided by the Virtual Telescope Project were published by the Minor Planet Center on its electronic circular MPEC 2017-B121.

Asteroid 2017 BH30 safely reached its minimum distance of about 70.000 km from us on 30 Jan. 2017 at 04:51 UT.

Over the years, our capability to detect small asteroids improved quite a lot, hence the apparently higher numbers of close approaches we see these days.

Comment: That would depend on how soon you want to detect them.

Forget About Global Warming: We're One Step From Extinction!

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Fireball 3

Meteor fireball observed across 11 southern U.S. states

Spencer Denton
wmcactionnews5
Mon, 30 Jan 2017 20:53 UTC
Fireball
If you saw a bright flash in the sky around 6:16 a.m., it wasn't lightning. It was a short trail, exploding fireball that lasted around three seconds.

Check out this still image captured by ArkansasSky.com near Greenbrier, Arkansas. They caught a big flash on their camera in the lower part of the sky between 20 and 30 degrees above the horizon.

There were several sightings in Collierville and scattered reports from Louisville, KY to Austin, TX. Check out the map to see all the sightings as of 9:30 a.m.

map meteor

Comment: The American Meteor Society (AMS) received 120 reports about a fireball seen over AR, TN, TX, MO, OK, KY, KS, IL, NE, LA and MS on Monday, January 30th 2017 around 12:13 UT.

AMS meteor fireball map 30.01.17
© AMS (screen capture)


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