☄️ An earth-crossing asteroid over half a mile wide visible in the sky

This Saturday, a large near-Earth asteroid over half a mile (1 km) in diameter will skim past Earth, and you can observe it with minimal equipment.

This asteroid, named (152637) 1997 NC1, was spotted nearly thirty years ago. It is speeding at 5.6 miles per second (9 km/s), an impressive pace. Its closest approach will occur on Saturday, June 27 at 11:14 GMT, at a distance of 1.59 million miles (2.56 million km) from our planet.

Curious observers equipped with binoculars or a small telescope can try to spot it.


Estimates of its size range between 0.47 and 1.03 miles (750 and 1,650 m). Despite its imposing size, the asteroid is not crossing our path.

The presence of the full moon could complicate observations. As Juan Luis Cano from ESA's Planetary Defence Office reports, moonlight may hinder visibility during the closest passage. Observers will therefore need to choose a dark spot and wait for the right time.

The asteroid will be visible in the Northern Hemisphere before its approach, then almost everywhere. Afterwards, only residents of the Southern Hemisphere will be able to follow it as it moves away. The essential condition remains a very dark sky, far from city lights.

Such a pass by an object of this size occurs only once every few years. This is a rare opportunity to observe a space giant with simple equipment. Amateur astronomers can take advantage of it, despite the moon's interference.

Asteroids

Asteroids are rocky bodies that orbit the Sun, with a large population between Mars and Jupiter. They range in size from a few feet to several hundred miles. They are considered remnants from the formation of the Solar System, 4.6 billion years ago.

Studying them helps us understand the history of our cosmic neighborhood. Some, like the one passing this Saturday, occasionally cross Earth's orbit. Fortunately, most are too small or too far away to pose a danger.

Near-Earth asteroids are monitored by detection programs. Their trajectories are precisely calculated to anticipate any impact risk. These observations also help prepare potential deflection missions.

Near-Earth Objects

Near-Earth objects (NEOs) are asteroids or comets whose orbits bring them close to Earth. They are classified based on their minimum orbital intersection distance with our planet. Those over 460 feet (140 m) are particularly monitored.

The European Space Agency and NASA coordinate telescope networks to spot them. Their trajectories are regularly updated. No major impact is expected in the coming decades.

Studying NEOs also helps to better understand impact risks and develop planetary defense strategies. Missions like DART have tested asteroid deflection, paving the way for protective technologies.