The year 2017 was favored with dire predictions of destructive giant impacts, and the 15 days of darkness “forecast by NASA” was back again. Unusually, there was no sign of the “Mars will look as big as the full Moon” that's been a regular since 2003. But there's also a new non-event.

Five Astronomy Non-events of 2017

Here is a woodcut of a Leonid shower. It was as seen at Niagara Falls, New York. Mechanics' Magazine said this illustration was made by an editor named Pickering "who witnessed the scene." It was before 1923, but that's all the information I could find.

from the internet comes a rather audacious meme appropriating the NASA logo for a nonsensical tale of 15 days of darkness.

Think of the whole Solar System. That's the Sun, the planets, dwarf planets, moons, asteroids, Kuiper Belt and other outer Solar System bodies, and comets. The mass of the Sun is 99.8% of the mass of the whole system. It's big and bright! Our view of it is dimmed by clouds, blotted out for a few minutes during a solar eclipse, and not seen when our part of the Earth turns away from it. But what could possibly darken it for 15 days?

Yet a blogger assured us the Sun would look like this for 15 days. (Not an astronomy blogger!) It's an event that hasn't happened for a million years, she says. I'd say make that 4.5 billion years, the age of the Earth.

The "green moon" was so obviously a joke that I didn't include it in the article. It certainly has captured the tone of the hoaxes, including putting the cause of the alleged phenomenon as a planetary alignment. I'll just mention here that various planetary alignments have happened often and will do so in the future. None of them have ever had any effect on the Earth.

Turn the four hundred and twenty years into numbers: 420, which the Urban Dictionary lists as a reference to marijuana. And turn that into a date: 4/20, April 20: it's weed day.

Green Moon - it's one way to encourage people to go out and look at the sky.

It's a thought, Angie. But perhaps they'd be discouraged by seeing that it wasn't green. On the other hand, the apparent color might depend on whether they'd added anything "special" to their brownies! (Is the Moon more likely to look green in Colorado, I wonder.)