How Much Does the Moon Weigh?

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iStock

How much does the moon weigh?

C Stuart Hardwick:

Nothing.

Okay, I’m being a bit pedantic. The mass of the moon, which might be what you mean to ask, is approximately 7.3476× 10^22 kilograms.

But the moon doesn’t weigh anything.

Weight is directly related to mass, but it’s not the same thing as mass (even through we call units of weight and mass by the same names). Weight is the force exerted by gravity against a body resting against a larger mass. The moon is in freefall—in orbit—so it doesn’t weigh anything. If it were placed on the surface of the Earth, it would weigh about 7.3476 × 10^22 kilograms—but only for a moment. Then it would collapse under its own weight and become a rather disastrous pimple on the Earth until it broke through the crust.

That would be a bad day.

But fortunately, there is no realistic way that could ever happen. The moon is in orbit, which means it’s falling toward Earth (which is why it doesn’t “feel” our gravity—it’s weightless), but it’s also coasting away into space such that for every meter it falls toward us, it moves far enough for Earth’s surface to curve away one meter. Therefore, like any orbiting body, it goes round and round and round.

This weight versus mass thing confuses a lot of folks because in colloquial English we use pounds and kilograms for both measurements of weight and mass. That is because we figured all this stuff out on Earth, where it was simple and practical to measure mass by measuring weight.

In other words, because we are earthlings, we define units of mass as equal to the observed units of weight as measured on Earth.

If you like science, you might like my free, award-winning sci-fi sampler.

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Why Do We Eat Cranberry Sauce on Thanksgiving?

MSPhotographic/iStock via Getty Images
MSPhotographic/iStock via Getty Images

While plenty of people eat turkey, mashed potatoes, and pie year-round, it seems like cranberry sauce almost exclusively exists in the Thanksgiving universe. Although we don’t know for sure whether it was eaten at the very first Thanksgiving, the jiggly, gelatinous side dish does have deep roots in the history of America’s fruited plains.

According to Insider, cranberries are one of only three commercially grown fruits native to the United States, and the Wampanoag tribe had been using them for food, dye, and medicine long before feasting with the Pilgrims in 1621. If there were cranberries at the party, they probably didn’t taste much like the sweetened sauce we’re (circumstantially) fond of today; at that point, the settlers hadn’t yet succeeded in growing sugar cane in the New World.

But a little more than 50 years later, according to a 1672 account cited by The Washington Post, the new Americans and Native Americans had both started to enjoy cranberries much like we do at Thanksgiving dinner: “Indians and English use it much, boyling them with Sugar for a Sauce to eat with their Meat.”

In 1796, Amelia Simmons—author of American Cookery, the first-ever American cookbook—took it one step further by recommending that roast turkey be served with cranberry sauce. Considering that the Library of Congress included the book on its list of “Books That Shaped America,” it’s possible that Simmons’s suggestion reverberated through kitchens across the nation, and the tradition gained momentum from there. She does mention pickled mangoes as an alternate side dish for turkey, but the then-Indian import was likely less common than the locally-grown cranberry.

Then, in the early 1800s, Ocean Spray revolutionized the labor-intensive process of hand-picking cranberries from vines with what’s called a wet harvest. Basically, farmers flood the bogs where cranberries grow, and then they wade into the water to collect the floating berries en masse.

farmer wet-harvesting cranberries
A farmer gathering cranberries during a wet harvest.
kongxinzhu/iStock via Getty Images

This was a more efficient technique, but a mass harvest meant that more cranberries got damaged. So in 1912, Ocean Spray began crushing them into canned, jellied cranberry sauce—maximizing the yield and making it easier than ever for every home in America to slice up a cylinder of solid, sugary, berry goodness.

Explore the stories behind your other favorite (or least favorite) Thanksgiving foods here.

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Why Do We Eat Pumpkin Pie at Thanksgiving?

gjohnstonphoto/iStock via Getty Images
gjohnstonphoto/iStock via Getty Images

While it’s possible—even probable—that pumpkins were served at the 1621 harvest festival that’s now considered the predecessor to Thanksgiving, attendees definitely didn’t dine on pumpkin pie (there was no butter or wheat flour to make crust).

The earliest known recipes for pumpkin pie actually come from 17th-century Europe. Pumpkins, like potatoes and tomatoes, were first introduced to Europe in the Columbian Exchange, but Europeans were more comfortable cooking with pumpkins because they were similar to their native gourds.

By the 18th century, however, Europeans on the whole lost interest in pumpkin pie. According to HowStuffWorks, Europeans began to prefer apple, pear, and quince pies, which they perceived as more sophisticated. But at the same time pumpkin pie was losing favor in Europe, it was gaining true staple status in America.

In 1796, Amelia Simmons published American Cookery, the first cookbook written and published in the New World colonies. Simmons included two recipes for “pompkin pudding” cooked in pastry crust. Simmons’s recipes call for “stewed and strained” pumpkin, combined with a mixture of nutmeg, allspice, and ginger (yes, it seems our pumpkin spice obsession dates back to at least the 1500s).

But how did pumpkin pie become so irrevocably tied with the Thanksgiving holiday? That has everything to do with Sarah Josepha Hale, a New Hampshire-born writer and editor who is often called the “Godmother of Thanksgiving.” In her 1827 abolitionist novel Northwood, Hale described a Thanksgiving meal complete with “fried chicken floating in gravy,” broiled ham, wheat bread, cranberry sauce, and—of course—pumpkin pie. For more than 30 years, Hale advocated for Thanksgiving to become a national holiday, writing regular editorials and sending letters to five American presidents. Thanksgiving was a symbol for unity in an increasingly divided country, she argued [PDF].

Abraham Lincoln eventually declared Thanksgiving a national holiday in 1863 (to near-immediate outcry from Southerners, who viewed the holiday as an attempt to enforce Yankee values). Southern governors reluctantly complied with the presidential proclamation, but cooks in the South developed their own unique regional traditions. In the South, sweet potato pie quickly became more popular than New England’s pumpkin pie (mostly because sweet potatoes were easier to come by than pumpkins). Now, pumpkin pie reigns supreme as the most popular holiday pie across most of the United States, although the Northeast prefers apple and the South is split between apple and pecan, another Southern staple.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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