Asteroid 2024 YR4 has popped up on the news again, offering both peril and opportunities,
A few months ago, NASA noted that 2024 YR4 had a 3.1 percent chance of hitting the Earth in 2032. Since the rock is 50 to 90 meters in diameter, if it were to hit the Earth, it would cause an explosion equivalent to a nuclear bomb with the accompanying devastation.
Subsequently, NASA dialed down the threat 2024 YR4 posed to the Earth and everyone breathed a sigh of relief.
Now, the Earth approaching asteroid has a new target. A small chance exists that it will hit the moon in 2032. The prospect presents new dangers, though not as great as the destruction of a city.
According to ZME Science, new data from the James Webb Space Telescope, 2024 YR4 has a 4.3 percent chance of hitting the moon on December 22, 2032. “If 2024 YR4 hits, it will create a blast equivalent to 6.5 million tons of TNT. The resulting crater would stretch about a kilometer across — bigger than almost any the Moon has seen in the last 5,000 years.”
Depending on whether the asteroid hits the near side of the moon —a 50-50 chance assuming it hits it at all — about 10 percent of the debris, about 100 million kilograms, ranging in size from flecks of dust to a small pebbles, could be captured by the Earth’s gravity and reach the atmosphere in perhaps three to five days.
Little if any debris kicked up by a lunar impact would threaten the Earth’s surface. At most, it would cause a spectacular meteor shower unlike anything in our lifetimes. Both scientists and casual sky watchers will be intrigued at this once in several millennia event.
The effects on space assets are another matter, however.
Satellites, ranging from relatively small Comsats to commercial space stations expected to be in operation by the 2030s, will be subjected to tiny objects traveling at tens of thousands of meters per second. SpaceX’s Starlink constellation will be at particular risk.
“This debris won’t likely destroy spacecraft and satellites, but it adds wear and tear,” writes ZME. “In rare cases, a lucky — or unlucky — piece of rock could disable a satellite or trigger a cascade of debris collisions.”
Both NASA and Chinese astronauts may be living and working on the moon at the time 2024 YR4 hits and will be in jeopardy due to falling debris or other hazards. The Lunar Gateway, if it exists in seven years, could also be subject to impacts.
What, if anything, can be done about it?
The option exists of doing nothing. After all, a four percent chance of the asteroid hitting the moon means a 96 percent chance of it not hitting the moon.
However, if the powers that be were to decide to divert 2024 YR4 so that it doesn’t hit the moon, the technical task should be relatively easy. NASA has already tested asteroid deflection with its DART mission, which diverted an asteroid named Dimorphos with a kinetic impactor.
The economic and political problems facing the diversion of 2024 YR4 are another matter. NASA is currently in turmoil due to proposed draconian budget cuts and a lack of a permanent administrator.
The Space Force, which is being lavished with money compared to NASA, might be assigned the task. Indeed, an asteroid diversion mission could be good practice for space operations by America’s newest military branch.
The other alternative is to perform a redirection mission to 2024 YR4 privately. One of the things that Jared Isaacman, the billionaire entrepreneur whose nomination to be NASA administrator President Trump abruptly withdrew, is contemplating is private science missions. An asteroid redirect mission might fit into that model.
One can see SpaceX’s Elon Musk financing such a mission. Musk has deep pockets and an incentive to divert 2024 YR4 if it threatens his Starlink constellation.
Asteroid diversion might become a good business for private launch companies such as SpaceX. If a really big space rock threatens the Earth, the nations of the world might be willing to pay a lot of money to ward it off. Someone like Elon Musk or Jeff Bezos, founder of SpaceX competitor Blue Origin, might literally save the world for a profit.
If such an asteroid is rich in useful natural resources, its diversion to a safe, stable orbit around the Earth would be even more profitable. Access to such a source of minerals could spark a space-based industrial revolution.
Save the world and get fabulously wealthy doing so. Someone really should make a movie out of that scenario, before it becomes true life.
Mark Whittington, who writes frequently about space policy, has published a political study of space exploration titled “Why is It So Hard to Go Back to the Moon?” as well as “The Moon, Mars and Beyond,” and, most recently, “Why is America Going Back to the Moon?” He blogs at Curmudgeons Corner.
