Full Buck Moon tonight!

WhatThe

(BBC Sky at Night)

The full Buck Moon rises this weekend. Find out when and how to make the most of the spectacle

The Buck Moon is the name given to the full Moon that occurs in July, and you'll be able to see it this weekend, the full Buck Moon rising on Sunday on 21st July at 22:05 BST.

A bright full Moon is a beautiful sight, and one of the most striking naked-eye phenomena visible in the night sky.

Many amateur astronomers avoid observing on nights when the Moon is big and bright, as it makes targets like meteor showers and deep-sky objects like galaxies and nebulae harder to see.

But for those of us who love gazing at the Moon with the naked eye, a full Moon is something to look forward to every month.

Here we'll look at what the Buck Moon actually means, when to see it and tips for making the most of it.

Why it's called a Buck Moon

Each full Moon of the year has its own informal nickname, leading to wonderful-sounding monikers like the Pink Moon, the Worm Moon and the Strawberry Moon.

Often full Moon nicknames are historic, and have come about because they denote a significant change or phenomenon in nature seen during that month.

Specifically, 'Buck Moon' refers to the fact that July is the time of year when male deer - known as 'bucks' - begin to grow their antlers, and is the beginning of game-hunting season.

Observing the Buck Moon

From the UK, the Buck Moon will rise on 21st July around 10pm and be visible in the southeast in the constellation of Capricornus.

The Moon will work its way across the southern part of the sky throughout the night, setting in the southwest in the early hours around dawn.

Many astronomers avoid a full Moon, because that's when the Moon's Earth-facing side is flooded with light, making features difficult to discern.

And yet it is a beautiful target to observe, particularly for kids and newcomers to astronomy.

The Moon illusion

A full Moon can look huge when close to the horizon. Credit: Joshua Rhoades

The Moon illusion i describes how a full Moon close to the horizon looks bigger than you might expect.

This is an optical illusion and is likely due to the fact that the Moon is closer to foreground objects and so seems to dwarf them, emphasising the Moon's size.

Observe the Buck Moon rising at the end of July and see if it looks much bigger to you.

An orange Moon

A full Moon sometimes looks orange when close to the horizon. Credit: Jamie Carter

The Buck Moon may appear orange, but this will be due to your perspective from Earth when observing it, rather than the Moon itself.

When the Moon is close to the horizon, it can sometimes appear rusty and red-coloured.

Low down, the Moon appears orange, and this effect is caused by sunlight bouncing off the Moon and passing through Earth's atmosphere.

Closer to the horizon, moonlight passes through a thicker part of Earth's atmosphere, causing scattering of blue and violet light.

The effect is that when we view a low-down Moon, it appears redder.

Observe the Buck Moon when it's rising and setting. Does it appear huge and orange?

Lunar halo

Lunar halo captured by Tom Wildoner, Pennsylvia, USA, 29 December 2020

You may see a bright halo around the Moon when you observe a full Moon, and this is a well-known phenomenon.

You see a halo around the Moon as moonlight passes through surrounding clouds, causing the appearance of rings of light and other phenomena.

If you're observing the Buck Moon, see if you can spot any tricks of light caused by the bright lunar glare.

Sandy_123

@whatThe What an interesting article you shared I will be looking for the moon tomorrow now

WhatThe

Sandy, thank you for spotting my deliberate mistake ha ha hee hee! Yes, it will be visible tonight and fully bucking tomorrow night 😄

Sandy_123

Ill look tomorrow deffo these things I find interesting I'm sure he lots of people taking photos

Jimm_Scope

I thought the moon looked particularly full last night! I do love it when it's just above the horizon and does look larger than when it is high in the sky.

Sandy_123

@WhatThe the moon looked beautiful last night I made a point of looking at it, was so big too it was only your thread that got me to know and look, really lovely it was