Lunar Eclipse 2018: How to watch the full moon turn red blood

On Friday, July 27, the full moon will pass through the shadow of the Earth. For 103 minutes, the usually silvery moon will become blood red and ocher. It will be the longest lunar lunar eclipse of the century, which will last 26 minutes longer than the last lunar eclipse in January.

Here's the good news: the vast majority of people on planet Earth will be able to see this lunar eclipse.

Here is the bad news: those of us in North America (with the exception of a slice of Newfoundland, Canada) will not see it at all.

Unfortunately, as night falls in North America and the full moon rises, the eclipse will already be over. The moon will have finished its crossing of the shadow of the Earth, or ombra. We will have to wait until January 21, 2019, by which time the next complete lunar eclipse will be visible here.

NASA

For readers in Australia, Asia, Africa, Europe and South America, all you have to do is go out at 5:14 pm UTC (1:14 pm ET) and search for the moon. It is then that begins the partial phase of the eclipse. The full eclipse starts at 19:30 UTC and then lasts an hour and 43 minutes! (Check precisely when the eclipse will take place where you live on TimeandDate.com.)

Enjoy! And tell us how it happened! Tweet the pictures on @voxdotcom . We will not be totally jealous or something like that.

If I can not see it, can I at least stream it?

We are in 2018. You do not have to do much without leaving your couch – eclipse display included.

The Slooh Astronomy Education Site will broadcast live the eclipse from 1 pm Eastern Time on July 27th. Look at it here.

The eclipse will still be very cool to watch, even on YouTube. This is a time-lapse replay of the last complete lunar eclipse in January. You can see the Earth slowly launching a blood orange shadow on the moon.

For more opportunities to contemplate the outdoor sky this summer, check out our guide. July 27 is also the best day to see Mars, as it will be directly aligned with the Earth and the sun.

Why do we have lunar eclipses?

The simple answer is "because the moon sometimes crosses the shadow of the Earth." But there is more than that.

For one, it must be a full moon. When the moon is full, it means that the sun, the Earth and the moon are aligned, like this:

Now you might think, "Why do not we have d & # 39; 39 Lunar eclipses at each full moon? "

The orbit of the moon does not fit perfectly with that of the Earth. It is tilted by 5 degrees:

NASA

Nobody knows exactly why – but this may have to do with how the moon probably formed: from a massive object its crushing on the Earth.

This means that during most full moons, the moon misses the moon, as you can see in the diagram above.

There are two points in the lunar orbit where the shadow can fall on the Earth. These are called nodes.

Joss Fong / Vox

For a total eclipse to occur, the moon must be at or very close to one of the nodes.

When the sun, the earth and the moon are lined up on a knot, that's it! The moon falls in the path of the shadow of the Earth.

NASA

There are usually two or three lunar eclipses in the given year, and any person lucky enough to be on the Earth 's night side during a lunar eclipse has a chance of having a lunar eclipse. to witness it.

You do not need special equipment or goggles to see it (unlike the total solar eclipse). But a pair of binoculars will give you a better more detailed view of the moon 's geography as it darkens in the shade.

Joss Fong / Vox

Why does the moon become red during a lunar eclipse?

Joe Klamar / AFP / Getty Images

During a total solar eclipse – like the one that North America saw last summer – the entire disc of the sun becomes blacker than bright, revealing the atmosphere of the sun.

What happens during a total lunar eclipse is a little less dramatic, but still beautiful.

When sunlight passes through the atmosphere, gases trap and diffuse blue light into the spectrum. (This is why the sky appears in blue.) The red, orange and yellow wavelengths pass in the shadow of the Earth and project on the moon.

Basically, as explained by Joss Fong of Vox, a total lunar eclipse is like projecting all the sunsets and sunrises on the moon.

Joss Fong / Vox

Watches: eclipses, explained