Why Doesn't Earth Have Rings?

Saturn, Jupiter, Neptune, and Uranus all have rings, so why not Earth? Turns out, it once did. 

Planetary rings are made of a combination of ice, rock, and dust particles. They can form in a number of ways: as the result of a collision that kicks up debris; when a planetary satellite gets too close and is pulled apart by the planet's gravity; or simply from debris left behind during the planet's formation.

In the case of Earth, the space debris went on to serve another purpose. As Julia Wilde of D News explains in the video above: "The Earth had a ring too once, it just coalesced into the Moon."

Not all rings become moons, thanks to the Roche limit. Named after the 19th-century astronomer who first described it, the Roche limit is "the minimum distance that a moon or other large object can be from a planet without being torn to bits," as NASA describes. That distance is 2.5 times the radius of the planet if the orbiting object and the planet have the same density. Because the Moon is outside the Earth-Moon Roche limit of 11,470 miles, it stays intact.

But it may not always. There are theories that say that the Moon will one day become space debris and potentially form a ring around Earth, thanks to the Sun's inevitable red giant phase. David Powell writes on Space.com that billions of years from now, "as the Earth and Moon near this blistering hot region, the drag caused by the Sun's extended atmosphere will cause the Moon's orbit to decay. The Moon will swing ever closer to Earth until it reaches a point 11,470 miles above our planet." So it's goodbye Moon and hello ring—at least, until chunks of rock from the short-lived ring "rain down onto Earth's surface," Powell writes. 

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Roadside Bear Statue in Wales is So Lifelike That Safety Officials Want It Removed
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iStock

Wooden bear statue.

There are no real bears in the British Isles for residents to worry about, but a statue of one in the small Welsh town of Llanwrtyd Wells has become a cause of concern. As The Telegraph reports, the statue is so convincing that it's scaring drivers, causing at least one motorist to crash her car. Now road safety officials are demanding it be removed.

The 10-foot wooden statue has been a fixture on the roadside for at least 15 years. It made headlines in May of 2018 when a woman driving her car saw the landmark and took it to be the real thing. She was so startled that she veered off the road and into a street sign.

After the incident, she complained about the bear to highways officials who agreed that it poses a safety threat and should be removed. But the small town isn't giving in to the Welsh government's demands so quickly.

The bear statue was originally erected on the site of a now-defunct wool mill. Even though the mill has since closed, locals still see the statue as an important landmark. Llanwrtyd Wells councilor Peter James called it an "iconic gateway of the town," according to The Telegraph.

Another town resident, who wished to remain anonymous, told The Telegraph that the woman who crashed her car had been a tourist from Canada where bears are common. Bear were hunted to extinction in Britain about 1000 years ago, so local drivers have no reason to look out for the real animals on the side of the road.

The statue remains in its old spot, but Welsh government officials plan to remove it themselves if the town doesn't cooperate. For now, temporary traffic lights have been set up around the site of the accident to prevent any similar incidents.

[h/t The Telegraph]

The Most Popular Infomercial Product in Each State

You don't have to pay $19.95 plus shipping and handling to discover the most popular infomercial product in each state: AT&T retailer All Home Connections is giving that information away for free via a handy map.

The map was compiled by cross-referencing the top-grossing infomercial products of all time with Google Trends search interest from the past calendar year. So, which crazy products do people order most from their TVs?

Folks in Arizona know that it's too hot there to wear layers; that's why they invest in the Cami Secret—a clip-on, mock top that gives them the look of a camisole without all the added fabric. No-nonsense New Yorkers are protecting themselves from identity theft with the RFID-blocking Aluma wallet. Delaware's priorities are all sorted out, because tons of its residents are still riding the Snuggie wave. Meanwhile, Vermont has figured out that Pajama Jeans are the way to go—because who needs real pants?

Unsurprisingly, the most popular product in many states has to do with fitness and weight loss, because when you're watching TV late enough to start seeing infomercials, you're probably also thinking to yourself: "I need to get my life together. I should get in shape." Seven states—Colorado, Idaho, Kentucky, Montana, Nebraska, Utah, and Wisconsin—have invested in the P90X home fitness system, while West Virginia and Arkansas prefer the gentler workout provided by the Shake Weight. The ThighMaster is still a thing in Illinois and Washington, while Total Gym and Bowflex were favored by South Dakota and Wyoming, respectively. 

Kitchen items are clearly another category ripe for impulse-buying: Alabama and North Dakota are all over the George Forman Grill; Alaska and Rhode Island are mixing things up with the Magic Bullet; and Floridians must be using their Slice-o-matics to chop up limes for their poolside margaritas.

Cleaning products like OxiClean (D.C. and Hawaii), Sani Sticks (North Carolina), and the infamous ShamWow (which claims the loyalty of Mainers) are also popular, but it's Proactiv that turned out to be the big winner. The beloved skin care system claimed the top spot in eight states—California, Mississippi, Nevada, New Mexico, Oklahoma, Oregon, Tennessee, and Texas—making it the most popular item on the map.

Peep the full map above, or check out the full study from All Home Connections here.

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