GOOD

Is This Where The Moon Really Comes From? New Research Points To “Yes”

An old theory gets new life as research points to a planetary collision as our Moon’s origin

Earlier this year, during a segment for the QVC home shopping network, fashion designer Isaac Mizrahi struggled to define what the moon actually is (“the moon is a planet, darling”) and faced, as a result, the wrath of the internet for not knowing—as I’m sure all of you do—that the moon is, obviously, Earth’s only natural satellite. As turns out, though, actual scientists (which Mr. Mizrahi is certainly not) have had their own troubles defining what the moon is, or more accurately—why it is the way it is.

For years, the prevailing explanation for the origin of Earth’s moon has been that at some point in our solar system’s early history an object roughly the size of Mars collided with—or more likely, careened off of—Earth. That object, the theory goes, was entirely destroyed upon impact, but its shattered remains eventually coalesced into what is now our moon. What scientists have found, though, is that on an isotopic level the moon is surprisingly similar to the Earth’s mantle. That’s problematic for the collision theory. If the moon is comprised of the remains of whatever hit us, it should display chemical traits similar to that object, rather than the Earth. For the moon to so closely resemble our planet, scientists theorized that the collision object itself would have needed an isotropic composition similar to our own—something their research indicated was extraordinarily unlikely.


image via (cc) flickr user markgregory

That wrench in the lunar-theory machine helped lend credence to a number of other, more isotopically plausible scenarios: Perhaps the moon was once part of Earth entirely, and was flung into orbit as our planet spun rapidly during its earliest state. Or perhaps our planet simply “snagged” a roving chunk of rock making its way through our solar system, locking it into a stable orbit around the Earth. To date, no single explanation has perfectly accounted for why our moon is the way it is, and how it got there. But now new research seems to indicate that the once questionable collision theory is, in fact, not only significantly more plausible than previously believed, but entirely likely.

In a paper published recently by Nature, Alessandra Mastrobuono-Battisti and Hagai Perets of the Technion-Israel Institute of Technology, along with Sean Raymond of the Laboratory of Astrophysics of Bordeaux, France describe a new series of simulations designed to explore how collisions between celestial bodies may have “fed” the creation of larger planets. They write:

We find that different planets formed in the same simulation have distinct compositions, but the compositions of giant impactors are statistically more similar to the planets they impact. A large fraction of planet–impactor pairs have almost identical compositions. Thus, the similarity in composition between the Earth and Moon could be a natural consequence of a late giant impact.

In other words, during our solar system’s early demolition derby days, odds are significantly higher than previously thought that we could end up with a collision which would result in the moon and the Earth being so chemically similar. How much higher? According to the researchers, anywhere from twenty to forty percent of the planet-impactor pairs met the criteria. Compare that with a 2007 Harvard simulation which put the number of objects hitting our planet with a similar isotopic makeup as our own at a measly one percent.

Which isn’t to say the collision-theory for the origin of our moon has been definitively proven. As Southwest Research Institute planetary scientist Robin Canup told sciencemag.org: “This is a very important piece of the puzzle.” Still, for a theory that had fallen out of favor with the scientific community, the team’s research offers a very significant boost. And as NASA readies itself for more missions to explore potentially life-sustaining moons like Jupiter’s Europa, steps toward understanding not only what we might find, but why we’re finding it, become all the more important.

[via sciencemag.org]

Articles
Ottawa Humane Society / Flickr

The Trump Administration won't be remembered for being kind to animals.

In 2018, it launched a new effort to reinstate cruel hunting practices in Alaska that had been outlawed under Obama. Hunters will be able to shoot hibernating bear cubs, murder wolf and coyote cubs while in their dens, and use dogs to hunt black bears.

Efforts to end animal cruelty by the USDA have been curtailed as well. In 2016, under the Obama Administration, the USDA issued 4,944 animal welfare citations, in two years the numbers dropped to just 1,716.

Keep Reading Show less
Science
via I love butter / Flickr

We often dismiss our dreams as nonsensical dispatches from the mind while we're deep asleep. But recent research proves that our dreams can definitely affect our waking lives.

People often dream about their significant others and studies show it actually affects how we behave towads them the next day.

"A lot of people don't pay attention to their dreams and are unaware of the impact they have on their state of mind," said Dylan Selterman, psychology lecturer at the University of Maryland, says according to The Huffington Post. "Now we have evidence that there is this association."

Keep Reading Show less
Health
via Real Time with Bill Maher / YouTube and The Late Late Show with James Corden / YouTube

A controversial editorial on America's obesity epidemic and healthcare by comedian Bill Maher on his HBO show "Real Time" inspired a thoughtful, and funny, response by James Cordon. It also made for a great debate about healthcare that Americans are avoiding.

At the end of the September 6th episode of "Real Time, " Maher turned to the camera for his usual editorial and discussed how obesity is a huge part of the healthcare debate that no one is having.

"At Next Thursday's debate, one of the candidates has to say, 'The problem with our healthcare system is Americans eat shit and too much of it.' All the candidates will mention their health plans but no one will bring up the key factor: the citizens don't lift a finger to help," Maher said sternly.

Keep Reading Show less
Politics

There is no shortage of proposals from the, um, what's the word for it… huge, group of Democratic presidential candidates this year. But one may stand out from the pack as being not just bold but also necessary; during a CNN town hall about climate change Andrew Yang proposed a "green amendment" to the constitution.

Keep Reading Show less
test
Me Too Kit

The creator of the Me Too kit — an at home rape kit that has yet to hit the market — has come under fire as sexual assault advocates argue the kit is dangerous and misleading for women.

The kit is marketed as "the first ever at home kit for commercial use," according to the company's website. "Your experience. Your kit. Your story. Your life. Your choice. Every survivor has a story, every survivor has a voice." Customers will soon be able order one of the DIY kits in order to collect evidence "within the confines of the survivor's chosen place of safety" after an assault.

"With MeToo Kit, we are able to collect DNA samples and other tissues, which upon testing can provide the necessary time-sensitive evidence required in a court of law to identify a sexual predator's involvement with sexual assault," according to the website.

Keep Reading Show less
Health