For the past few months, Earth has been home to a “second moon,” but it’s much smaller than our main lunar companion. Unlike the Moon, this “mini-moon” was not expected to exist forever.
This mini-moon is officially known as asteroid 2024 PT5. After first merging with Earth on September 29, 2024, the mini-moon left orbit around Earth on Monday (November 25) at 10:43 a.m. ET (15:43 GMT), and on the 19th. He didn’t stay long enough to celebrate Thanksgiving. Thursday (November 28th).
But don’t be sad about this separation. The 37-foot-wide (11.2-meter) asteroid is the equivalent of six Arnold Schwarzeneggers stacked on top of each other, and will come back just like Arnie in The Terminator. The question is whether PT5 in 2024 will enjoy new magic as the second moon around Earth.
While the asteroid 2024 PT5 is occupied around Earth, Space.com reports that Carlos de la Fuente Marcos of the Complutense University of Madrid, one of the scientists who discovered its orbit and status as a mini-satellite, I have been communicating with Mr.
Marcos is part of a team studying the minimoon capture event. They regularly monitor newly discovered objects and discovered the unique dynamical properties of 2024 PT5. He is also involved in the study of PT5 in 2024 during its orbit around Earth, which revealed that the minimoon was likely created when rock was removed from the moon by an impact. It has become.
Marcos told Space.com that the asteroid is part of the Arjuna asteroid belt, a secondary asteroid belt made up of objects that typically orbit the sun in orbits very similar to Earth’s. I explained. These Arjuna asteroids are typically located an average distance of about 93 million miles (150 million kilometers) from the solar system’s central star.
“The objects in the Arjuna asteroid belt are part of the near-Earth body of asteroids and comets,” Marcos explained in September, noting that these asteroids come close to Earth at a distance of about 2.8 million miles (4.5 million km). Once it gets close, its slow speed of about 2,200 miles per hour (3,540 km per hour) means it could be captured by Earth’s gravity.
“If a true satellite is like a customer buying something in a store, then objects like 2024 PT5 might be window shoppers,” he continued.
Return of the space window shopper
use of NASA JPL Small Astronomical Object Search Databaseit is possible to consider several upcoming approaches for 2024 PT5 and see if any meet the criteria needed to conquer it, at least tentatively.
The next time 2024 PT5 will approach Earth will be on January 9, 2025, according to a database containing details of the orbits of more than 3.3 million known asteroids and comets. At this time, the asteroid will be within about 1.1 million miles (1.8 million km) of Earth and will be traveling at about 2,300 miles per hour (3,700 kilometers per hour).
That means that during this visit, when the asteroid approaches the moon in a few days, it may be moving a little too fast to be captured by Earth’s gravity.
After this, astronomers will have to wait a while for PT5’s next return in 2024, with the next approach set for November 8, 2055.
At that point, the asteroid will slowly approach, traveling at just 1,498 miles per hour, but will only come within 3.3 million miles of Earth. So the 2055 approach may be a little too wide for 2024 PT5 to trap Earth as a minimoon.
“As for the future, it’s almost certain we’ll be back in 2055. Using the latest data, total geocentric energy will be negative.” [needed for gravitational capture to occur] “From late October 6, 2055 to early morning October 14, 2055,” Marcos said. “However, at this point it will remain at 3.3 million miles.” [5.3 million km] From the earth. It will remain for more than 28 million miles, so it will not become a temporary satellite of the Earth. [45 million km] From our earth. A previous orbit determination would have captured it in 2055. Capture events are not fired for the latest data. ”
After this, the next few encounters between Earth and PT5 in 2024 may be subject to large uncertainties, depending on how far into the future we project this small object’s orbit. At present, the next close encounter with PT5 in 2024 is believed to occur another 29 years later, on January 7, 2084, when the asteroid will once again move at a speed of about 1 million miles, an estimated They will come within about 1 million miles of each other. 2,300 mph (3,700 km/h).
The asteroid will then quickly return to Earth on May 8, 2084, coming within about 2 million miles of Earth at an estimated speed of 2,013 miles (3,240 kilometers per hour). So this visit, the first in just over 59 years, seems most likely, at least numerically and for now, that PT5 in 2024 will be another minimoon for Earth.
But if you don’t want to wait 60 years to experience the excitement of catching another minimoon, don’t worry.
Marcos pointed out that long-term capture of small satellites is quite rare. Only two have been recorded: RH120 in 2006 and CD3 in 2020, each of which stayed in orbit for about a year. However, short-term captures lasting just a few weeks, such as PT5 in 2024, are fairly common, and these events occur on average several times per decade.
That’s why the researcher is not feeling sentimental about PT5’s departure in 2024, despite his important work on space rocks.
“I won’t be too sad when PT5 ends in 2024. Minimoons come and go as they wish. I’m just waiting for the next one,” Marcos said. . “The wait won’t be that long. The next capture will probably occur in the next few months. The ongoing near-Earth object survey is now sensitive enough to capture these objects on a regular basis. ”
