There's a Second Moon—a Mini-Moon—in Earth's Orbit

dottedhippo, iStock via Getty Images
dottedhippo, iStock via Getty Images

Moons are common in our solar system. In simple terms, a moon is a natural satellite caught in a planet's orbit. Based on that definition, a second moon—a mini-moon—has been circling Earth for a few years undetected by scientists, The Atlantic reports.

The Minor Planet Center—an international organization that studies asteroids, comets, and small natural satellites orbiting planets—announced recently that Earth has a new natural satellite of its own. The object, dubbed 2020 CD3, is roughly the size of a small car, and it's the only one of our planet's satellites, other than the actual Moon, that wasn't put into orbit by humans.

Astronomers concluded that 2020 CD3 has been there for at least a year and up to three, evading observation until February 15, 2020. It's not totally clear what the object it is, but most likely it was an asteroid that was pulled off course by Earth's gravity while flying close to the planet. There's a smaller chance it's a piece of the moon that flew into space following an impact.

The Moon's status as Earth's no.1 satellite isn't under threat. Mini-moons such as this one may appear fairly often, but because they're too small to reflect the Sun or be seen with the naked eye, most aren't documented before exiting orbit. The gravitational tug-of-war between the Moon, the Earth, and the Sun makes for unstable trajectories for such small objects, which eventually causes them to slip back into outer space. 2020 CD3, for instance, takes a wild, looping path around Earth that lasts about four months. The mini-moon may break away from our planet as early as April 2020.

2020 CD3 isn't the only noteworthy object in orbit. Here are five human-made things you can see from space.

[h/t The Atlantic]

Take Advantage of Amazon's Early Black Friday Deals on Tech, Kitchen Appliances, and More

Amazon
Amazon

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Even though Black Friday is still a few days away, Amazon is offering early deals on kitchen appliances, tech, video games, and plenty more. We will keep updating this page as sales come in, but for now, here are the best Amazon Black Friday sales to check out.

Kitchen

Instant Pot/Amazon

- Instant Pot Duo Plus 9-in-115 Quart Electric Pressure Cooker; $90 (save $40) 

- Le Creuset Enameled Cast Iron Signature Sauteuse 3.5 Quarts; $180 (save $120)

- KitchenAid KSMSFTA Sifter with Scale Attachment; $95 (save $75) 

- Keurig K-Mini Coffee Maker; $60 (save $20)

- Cuisinart Bread Maker; $88 (save $97)

- Anova Culinary Sous Vide Precision Cooker; $139 (save $60)

- Aicook Juicer Machine; $35 (save $15)

- JoyJolt Double Wall Insulated Espresso Mugs - Set of Two; $14 (save $10) 

- Longzon Silicone Stretch Lids - Set of 14; $13 (save $14)

HadinEEon Milk Frother; $37 (save $33)

Home Appliances

Roomba/Amazon

- iRobot Roomba 675 Robot Vacuum with Wi-Fi Connectivity; $179 (save $101)

- Fairywill Electric Toothbrush with Four Brush Heads; $19 (save $9)

- ASAKUKI 500ml Premium Essential Oil Diffuser; $22 (save $4)

- Facebook Portal Smart Video Calling 10 inch Touch Screen Display with Alexa; $129 (save $50)

- Bissell air320 Smart Air Purifier with HEPA and Carbon Filters; $280 (save $50)

Oscillating Quiet Cooling Fan Tower; $59 (save $31) 

TaoTronics PTC 1500W Fast Quiet Heating Ceramic Tower; $55 (save $10)

Vitamix 068051 FoodCycler 2 Liter Capacity; $300 (save $100)

AmazonBasics 8-Sheet Home Office Shredder; $33 (save $7)

Ring Video Doorbell; $70 (save $30) 

Video games

Sony

- Marvel's Spider-Man: Game of The Year Edition for PlayStation 4; $20 (save $20)

- Marvel's Avengers; $27 (save $33)

- Minecraft Dungeons Hero Edition for Nintendo Switch; $20 (save $10)

- The Last of Us Part II for PlayStation 4; $30 (save $30)

- LEGO Harry Potter: Collection; $15 (save $15)

- Ghost of Tsushima; $40 (save $20)

BioShock: The Collection; $20 (save $30)

The Sims 4; $20 (save $20)

God of War for PlayStation 4; $10 (save $10)

Days Gone for PlayStation 4; $20 (save $6)

Luigi's Mansion 3 for Nintendo Switch; $40 (save $20)

Computers and tablets

Microsoft/Amazon

- Apple MacBook Air 13 inches with 256 GB; $899 (save $100)

- New Apple MacBook Pro 16 inches with 512 GB; $2149 (save $250) 

- Samsung Chromebook 4 Chrome OS 11.6 inches with 32 GB; $210 (save $20) 

- Microsoft Surface Laptop 3 with 13.5 inch Touch-Screen; $1200 (save $400)

- Lenovo ThinkPad T490 Laptop; $889 (save $111)

- Amazon Fire HD 10 Tablet (64GB); $120 (save $70)

- Amazon Fire HD 10 Kids Edition Tablet (32 GB); $130 (save $70)

- Samsung Galaxy Tab A 8 inches with 32 GB; $100 (save $50)

Apple iPad Mini (64 GB); $379 (save $20)

- Apple iMac 27 inches with 256 GB; $1649 (save $150)

- Vankyo MatrixPad S2 Tablet; $120 (save $10)

Tech, gadgets, and TVs

Apple/Amazon

- Apple Watch Series 3 with GPS; $179 (save $20) 

- SAMSUNG 75-inch Class Crystal 4K Smart TV; $998 (save $200)

- Apple AirPods Pro; $169 (save $50)

- Nixplay 2K Smart Digital Picture Frame 9.7 Inch Silver; $238 (save $92)

- All-New Amazon Echo Dot with Clock and Alexa (4th Gen); $39 (save $21)

- MACTREM LED Ring Light 6" with Tripod Stand; $16 (save $3)

- Anker Soundcore Upgraded Bluetooth Speaker; $22 (save $8)

- Amazon Fire TV Stick with Alexa Voice Remote; $28 (save $12)

Canon EOS M50 Mirrorless Camera with EF-M 15-45mm Lens; $549 (save $100)

DR. J Professional HI-04 Mini Projector; $93 (save $37)

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Don't Miss Saturn And Jupiter's Great Conjunction on the Winter Solstice

Paul Williams, Flickr // CC BY-ND 2.0
Paul Williams, Flickr // CC BY-ND 2.0

In 2020, skygazers were treated to meteor showers, a new comet, and a Halloween blue moon. One of the last major astronomical events of the year is set to fall on the night of the winter solstice. On December 21, look up to catch Saturn in conjunction with Jupiter.

What is the conjunction of Saturn and Jupiter?

In astronomy, a conjunction occurs when two planets appear exceptionally close in the night sky. Two of our solar system's gas giants will share a celestial "kiss" on the longest night of the year. The rare meeting of Saturn and Jupiter is known as the "great conjunction" by astronomers.

Though conjunctions between the planets are fairly common, Saturn and Jupiter only get together once in a generation. Their last conjunction happened 20 years ago in the year 2000. Even if you were around for the last one, 2020's planetary meet-up is worth catching. Saturn and Jupiter will come within 0.1° of each other, or about one-fifth the width of a full moon. The last time the two planets came that close was in 1653, and they won't match that proximity again until 2080.

How to see the conjunction of Saturn and Jupiter

Saturn and Jupiter have been inching closer throughout October and November. You can find them now by looking for Jupiter, currently the brightest planet in the night sky, right after sunset. Saturn will appear just east of Jupiter as a dimmer planet with a golden hue.

As autumn wanes, the two planets will gradually bridge the space between them until they reach conjunction on winter solstice. On Monday, December 21, the planets will be so close that they may form a coalescence. That happens when the light from two planets appear to shine as a single star. When that happens, the super-bright body will be easy to spot.