Eclipses Belong to Families That Span Millennia

iStock
iStock

If you’re lucky enough to see the solar eclipse when it passes over America on August 21, you’ll bear witness to a centuries-long legacy. That’s because total eclipses of the sun aren’t isolated incidents that occur at random. They belong to interconnected eclipse families that humans have been using to track the phenomena since long before the first telescope was invented.

In the latest installment of StarTalk on Mashable, Neil deGrasse Tyson chats with meteorologist Joe Rao about the science behind eclipse families. According to Rao, eclipses follow Saros cycles which repeat every 18 years, 11 days, 8 hours. Astronomers keep track of many different Saros cycles. The eclipse on August 21, for example, is a member of the family Solar Saros 145. Every 18 years a Saros 145 eclipse falls over a different third of the Earth. In 1999, the great American eclipse’s “cousin” appeared in the skies over Europe and south Asia, and 18 years before that another relative could be seen over modern Russia. The Solar Saros clan can be traced all the way back to 1639 and it will keep going until 3009.

Today, scientists have space-age technology that allows them to track the moment of totality down to a fraction of a second. But thousands of years ago, before such satellite-tracking equipment was invented, ancient Babylonians only knew what they could observe from Earth. Their eclipse calculations ended up serving them pretty well: They were able to predict the same 18-year cycle we know to be true today.

Saros 145 isn’t the only family of eclipses making its way around the Earth. There are enough solar eclipse cycles to make the event a fairly common occurrence. If you’re curious to see how many will happen in your lifetime, here’s where you can calculate the number.

[h/t Mashable]

10 Products for a Better Night's Sleep

Amazon/Comfort Spaces
Amazon/Comfort Spaces

Getting a full eight hours of sleep can be tough these days. If you’re having trouble catching enough Zzzs, consider giving these highly rated and recommended products a try.

1. Everlasting Comfort Pure Memory Foam Knee Pillow; $25

Everlasting Comfort Knee Pillow
Everlasting Comfort/Amazon

For side sleepers, keeping the spine, hips, and legs aligned is key to a good night’s rest—and a pain-free morning after. Everlasting Comfort’s memory foam knee pillow is ergonomically designed to fit between the knees or thighs to ensure proper alignment. One simple but game-changing feature is the removable strap, which you can fasten around one leg; this keeps the pillow in place even as you roll at night, meaning you don’t have to wake up to adjust it (or pick it up from your floor). Reviewers call the pillow “life-changing” and “the best knee pillow I’ve found.” Plus, it comes with two pairs of ear plugs.

Buy it: Amazon

2. Letsfit White Noise Machine; $21

Letsfit White Noise Machine
Letsfit/Amazon

White noise machines: They’re not just for babies! This Letsfit model—which is rated 4.7 out of five with nearly 3500 reviews—has 14 potential sleep soundtracks, including three white noise tracks, to better block out everything from sirens to birds that chirp enthusiastically at dawn (although there’s also a birds track, if that’s your thing). It also has a timer function and a night light.

Buy it: Amazon

3. ECLIPSE Blackout Curtains; $16

Eclipse Black Out Curtains
Eclipse/Amazon

According to the National Sleep Foundation, too much light in a room when you’re trying to snooze is a recipe for sleep disaster. These understated polyester curtains from ECLIPSE block 99 percent of light and reduce noise—plus, they’ll help you save on energy costs. "Our neighbor leaves their backyard light on all night with what I can only guess is the same kind of bulb they use on a train headlight. It shines across their yard, through ours, straight at our bedroom window," one Amazon reviewer who purchased the curtains in black wrote. "These drapes block the light completely."

Buy it: Amazon

4. JALL Wake Up Light Sunrise Alarm Clock; $38

JALL Wake Up Light Sunrise Alarm Clock
JALL/Amazon

Being jarred awake by a blaring alarm clock can set the wrong mood for the rest of your day. Wake up in a more pleasant way with this clock, which gradually lights up between 10 percent and 100 percent in the 30 minutes before your alarm. You can choose between seven different colors and several natural sounds as well as a regular alarm beep, but why would you ever use that? “Since getting this clock my sleep has been much better,” one reviewer reported. “I wake up not feeling tired but refreshed.”

Buy it: Amazon

5. Philips SmartSleep Wake-Up Light; $200

Philips SmartSleep Wake-Up Light
Philips/Amazon

If you’re looking for an alarm clock with even more features, Philips’s SmartSleep Wake-Up Light is smartphone-enabled and equipped with an AmbiTrack sensor, which tracks things like bedroom temperature, humidity, and light levels, then gives recommendations for how you can get a better night’s rest.

Buy it: Amazon

6. Slumber Cloud Stratus Sheet Set; $159

Stratus sheets from Slumber Cloud.
Slumber Cloud

Being too hot or too cold can kill a good night’s sleep. The Good Housekeeping Institute rated these sheets—which are made with Outlast fibers engineered by NASA—as 2020’s best temperature-regulating sheets.

Buy it: SlumberCloud

7. Comfort Space Coolmax Sheet Set; $29-$40

Comfort Spaces Coolmax Sheets
Comfort Spaces/Amazon

If $159 sheets are out of your price range, the GHI recommends these sheets from Comfort Spaces, which are made with moisture-wicking Coolmax microfiber. Depending on the size you need, they range in price from $29 to $40.

Buy it: Amazon

8. Coop Home Goods Eden Memory Foam Pillow; $80

Coop Eden Pillow
Coop Home Goods/Amazon

This pillow—which has a 4.5-star rating on Amazon—is filled with memory foam scraps and microfiber, and comes with an extra half-pound of fill so you can add, or subtract, the amount in the pillow for ultimate comfort. As a bonus, the pillows are hypoallergenic, mite-resistant, and washable.

Buy it: Amazon

9. Baloo Weighted Blanket; $149-$169

Baloo Weighted Blanket
Baloo/Amazon

Though the science is still out on weighted blankets, some people swear by them. Wirecutter named this Baloo blanket the best, not in small part because, unlike many weighted blankets, it’s machine-washable and -dryable. It’s currently available in 12-pound ($149) twin size and 20-pound ($169) queen size. It’s rated 4.7 out of five stars on Amazon, with one reviewer reporting that “when it's spread out over you it just feels like a comfy, snuggly hug for your whole body … I've found it super relaxing for falling asleep the last few nights, and it looks nice on the end of the bed, too.” 

Buy it: Amazon 

10. Philips Smartsleep Snoring Relief Band; $200

Philips SmartSleep Snoring Relief Band
Philips/Amazon

Few things can disturb your slumber—and that of the ones you love—like loudly sawing logs. Philips’s Smartsleep Snoring Relief Band is designed for people who snore when they’re sleeping on their backs, and according to the company, 86 percent of people who used the band reported reduced snoring after a month. The device wraps around the torso and is equipped with a sensor that delivers vibrations if it detects you moving to sleep on your back; those vibrations stop when you roll onto your side. The next day, you can see how many hours you spent in bed, how many of those hours you spent on your back, and your response rate to the vibrations. The sensor has an algorithm that notes your response rate and tweaks the intensity of vibrations based on that. “This device works exactly as advertised,” one Amazon reviewer wrote. “I’d say it’s perfect.”

Buy it: Amazon

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July's Last Quarter Moon Is Coming This Weekend

When the Moon hits your eye like half a pizza pie, that's a quarter moon.
When the Moon hits your eye like half a pizza pie, that's a quarter moon.
halfbottle/iStock via Getty Images

If you scan the sky after the sun sets this Sunday, July 12, you’ll see this month’s last quarter moon. And if you’re a novice sky-gazer, you might be surprised to find that half—not a quarter—of the moon is illuminated.

The name isn’t related to how much of the moon is visible, but rather, which phase of its monthly orbit around Earth it’s currently in. The Old Farmer’s Almanac suggests picturing the cycle like a baseball diamond: A new moon (which you can’t see at all) is home plate; a first quarter moon is first base; a full moon is second base; and a third (or last) quarter moon is third base. In other words, the last quarter moon marks the last quarter of the cycle before we get another new moon. And since we can see half of it, it’s sometimes colloquially called a half moon.

lunar orbit cycle illustration
The Moon, Earth's biggest curveball.
VectorMine/iStock via Getty Images

As EarthSky reports, July’s last quarter moon hits its peak at 7:29 p.m. EDT on Sunday night, but you can wait until the sky gets darker for a clearer view. Though it’s not the last last quarter moon of the year, this one is extra special. Since it peaks just four hours after the lunar apogee—the point in the moon’s orbit when it’s farthest from Earth—July’s last quarter moon will be farther from the Earth than any other quarter moon this year.

It won’t appear noticeably dimmer or more distant to the naked eye, but it’s still a cool fact to mention to whomever happens to be around on Sunday night. On the following nights, you can watch the waning crescent grow slimmer and slimmer until the moon disappears completely on July 20 and starts the cycle over again.

[h/t EarthSky]