A fascinating astronomical event is coming up on September 29, when the Earth will acquire a sort of “second moon”. It is actually an asteroid about 10 meters in size, called 2024 PT5discovered on August 7, 2024 by theAsteroid Terrestrial-impact Last Alert System from Sutherland, South Africa.
When the “second moon” arrives
When we talk about asteroids, our thoughts immediately go to catastrophe films or to the one that made the dinosaurs extinct on our planet millions of years ago, but 2024 PT5 will be none of that. This large rock, tiny if we think about the size of the universe, will be captured by the Earth’s gravity for about two months before resuming its journey through the solar system. It will not complete a revolution of our planet, but will only complete a horseshoe path before returning to its heliocentric path.
Will enter in orbit around the Earth on September 29, 2024 at 20:02 Italian time, remaining for only two months and returning to its heliocentric path, 56.6 days later, on November 25 at 10:33. After this first approach there will be another in January 2025 and subsequently in 2055, even in these last two cases, do not worry, the Earth will not suffer any kind of problem.
Where is the asteroid coming from?
2024 PT5 is a NEA (Near-Earth Asteroid) that is part of the Arjuna’s asteroidsa secondary asteroid belt composed mainly of rocks that follow orbits very similar to that of the Earth at an average distance from the Sun of about 150 million kilometers. Some of these rocks or large boulders, can approach the Earth at a close distance of about 4.5 million km, and at low speeds of about 3,540 km/h. In these conditions, the geocentric energy of the object can become negative, for this reason what is called “gravitational capture” by the Earth occurs, making it become a sort of temporary second Moon.
How can it be observed?
2024 PT5, during its orbit around Earth, it will not be visible to the vast majority of observatories. “The object is too small for typical amateur telescopes and binoculars,” said Carlos de la Fuente Marcos, a professor at the Universidad Complutense de Madrid and lead author of the 2024 PT5 research.
To observe it, you would need a telescope with a diameter of at least 30 inches (about 51 cm) and a CCD or CMOS detector.
The importance of the event
This rare event will provide scientists with a unique opportunity to study a near-Earth object. At the same time, it will help refine our asteroid detection systems.