I got this notice in email from NASA about a surprise asteroid that gave us only one day of warning passing halfway between the Earth and the moon. It was the largest known asteroid to ever pass that close to Earth in observational history.SURPRISE ASTEROID FLYBY: With little warning, on Sunday, April 15th,2018 GE3 was discovered just the day before as it plunged inward from the asteroid belt. A quick-thinking amateur astronomer in Europe was able to record a video of the asteroid as it flew by.With little warning, a relatively large asteroid flew through the Earth-Moon system on April 15th only 192,200 km (0.5 Lunar Distance) from our planet. 2018 GE3 was discovered by the Catalina Sky Survey approaching Earth on April 14th. Hours later, amateur astronomer Michael Jäger of Weißenkirchen Austria video-recorded the space rock rushing through the southern constellation Serpens:According to Wikipedia , 2018 GE3 is the largest known asteroid to pass that close to Earth in observational history," says Jäger. "It was shining like a 13th magnitude star at the time of my observations."This puts it into the same class as the 60-meter Tunguska impactor that leveled a forest in Siberia in 1908. A more recent point of comparison is the Chelyabinsk meteor-a ~20-meter asteroid that exploded in the atmosphere over Russia on Feb. 15, 2013, shattering windows and toppling onlookers as a fireball brighter than the sun blossomed in the blue morning Ural sky. 2018 GE3 could be 5 to 6 times wider than that object.Based on an observational arc of only 1 day, 2018 GE3 appears to follow an elliptical orbit which stretches from the asteroid belt to deep inside the inner solar system. Every ~2.5 years the space rock crosses the orbits of Mercury, Venus, Earth, and Mars - although not necessarily making close approaches to the planets themselves.NASA Jet Propulsion Laboratory has made an interactive orbit viewer available online here </s> A small asteroid — which had just been discovered earlier in the day — disintegrated over Africa on Saturday, NASA said.

The tiny space rock, roughly six feet long, entered Earth’s atmosphere at the high speed of 38,000 mph and broke apart several miles above the surface, creating a bright fireball that lit up the evening sky, the agency said.

The event was witnessed by a number of observers and was caught on webcam video.

The object surprised astronomers shortly after its discovery, when its trajectory suggested it would pass very, very close to Earth just hours later, according to EarthSky.org.

When it was spotted, astronomers realized there was a possibility of an Earth impact. However, the asteroid was determined to be very small and therefore harmless.

“This was a much smaller object than we are tasked to detect and warn about,” said Lindley Johnson, Planetary Defense Officer at NASA Headquarters. “However, this real-world event allows us to exercise our capabilities and gives some confidence our impact prediction models are adequate to respond to the potential impact of a larger object.”

The object was first given the temporary designation of ZLAF9B2, but has now been renamed as asteroid 2018 LA by the International Astronomical Union.

It was much smaller than the meteor that exploded over Chelyabinsk, Russia, in February 2013, which was an estimated 60 feet wide. That meteor broke windows in six Russian cities and caused more than 1,500 people to seek medical attention, mostly due to injuries from flying glass, EarthSky said.

These are the discovery observations of asteroid 2018 LA from the Catalina Sky Survey, taken June 2, 2018. About eight hours after these images were taken, the asteroid entered Earth's atmosphereand disintegrated in the upper atmosphere near Botswana, Africa.
The Zwicky Transient Facility in California discovers a large Atira asteroid, 2019 AQ3, an asteroid with a diameter of 1.4 kilometres (0.87 miles) that stays closer to the Sun during its orbit than any other known asteroid, passing from inside the orbit of Mercury to just outside the orbit of Venus.