A newly discovered, “potentially hazardous” asteroid almost the size of the world’s tallest skyscraper is set to tumble past Earth just in time for Halloween, according to NASA.

The asteroid, called 2022 RM4, has an estimated diameter of between 1,083 and 2,428 feet (330 and 740 meters) — just under the height of Dubai’s 2,716-foot-tall (828 m) Burj Khalifa, the tallest building in the world. It will zoom past our planet at around 52,500 mph (84,500 km/h), or roughly 68 times the speed of sound, according to NASA (opens in new tab).

The bad news is NASA estimates that it tracks only about 40 percent of the asteroids large enough that they could cause calamity if they were to hit Earth. To save us, the space agency needs fair warning — years, not months or weeks — to muster the defenses in space needed to safeguard the planet.

“As we say, we can’t do anything about them unless we know about them, and when they might be a concern for us,” Lindley Johnson, NASA’s Planetary Defense Officer, said in an interview.

New research suggests that the asteroid responsible for forming Earth’s largest impact crater was even bigger than researchers had previously estimated.

But they also offer an explanation of the solar system’s earliest days | Science & technology.

Last night at 23:14 UTC, NASA’s DART spacecraft successfully struck asteroid Dimorphos, the 160-metre moonlet orbiting around the larger Didymos asteroid. About 38 seconds later, the time it took for the light to arrive at Earth, people all over the world saw the abrupt end of the live stream from the spacecraft, signalling that the impact had happened successfully – DART was no more.

Astronomers on a small slice of our planet’s surface, extending from southern and eastern Africa to the Indian Ocean and the Arabian Peninsula, could actually watch it live with their telescopes. Among those were a half dozen stations joined together for a dedicated observing campaign organised by ESA’s Planetary Defence Office and coordinated by the team of observers of the Agency’s Near-Earth Object Coordination Centre (NEOCC). As usual, when such a timely astronomical event happens, not all stations were successful in their observations: clouds, technical problems and other issues always affect real-life observations.

However, a few of ESA’s collaborating stations could immediately report a successful direct confirmation of DART’s impact. Among them was the team of the Les Makes observatory, on the French island of La Reunion in the Indian Ocean. The sequence of images they provided in real time was impressive: the asteroid immediately started brightening upon impact, and within a few seconds it was already noticeably brighter. Within less than a minute a cloud of ejected material became visible and could be followed while it drifted eastwards and slowly dissipated.

Bet the dinosaurs wish they’d thought of this.

NASA on Monday will attempt a feat humanity has never before accomplished: deliberately smacking a spacecraft into an asteroid to slightly deflect its orbit, in a key test of our ability to stop cosmic objects from devastating life on Earth.

The Double Asteroid Redirection Test (DART) spaceship launched from California last November and is fast approaching its target, which it will strike at roughly 14,000 miles per hour (23,000 kph).