How make the most of a full Moon

Some will tell you a full Moon is the worst time to observe our lunar neighbour, but there's still plenty to see when the Moon is fully illuminated.

Sarah and Simon Fisher, Bromsgrove, Worcestershire. Sarah and Simon say:

When the Moon is full its bright disc lights up the sky, frustrating observers of faint galaxies and annoying imagers wanting to take long exposures without gradients spoiling their shots.

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Grumbling about such inconveniences is perfectly reasonable, of course, but there are some people that take a more defeatist attitude to the full Moon, that it is the worst of the Moon’s phases.

They say the bright lunar leaves little else to see, or wonder conspiratorially why the skies only seem to be clear when the Moon is shining.

If you’re concerned about imaging when the Moon is bright, read our guide to astrophotography during a full Moon.

Full Moon rising Peter Sculthorpe, Liverpool, 19 April 2019 Equipment: Canon EOS 7D DSLR camera, Canon 100-400mm lens, tripod.
Full Moon rising, by Peter Sculthorpe, Liverpool, 19 April 2019. Equipment: Canon EOS 7D DSLR camera, Canon 100-400mm lens, tripod.

The full Moon is sometimes unfairly characterised as being… well, a bit bland. At full Moon the landscape on the Earth-facing side of the lunar globe is lit from directly above, meaning that the dramatic shadows and relief we see during other phases is gone.

The result is that the spectacular textures of the Moon’s craggy surface are rendered almost invisible, and many mountains and craters seem to disappear into their surroundings.

Many astronomers will tell you not to bother observing the full Moon, as it’s best seen during the crescent and gibbous phases, when shadows are cast and the terminator (the shadow and relief-rich boundary between the illuminated and unlit portion of the Moon) emphasises topographical features.

But there is still plenty to enjoy during a full Moon. In this guide we’re going to celebrate the full Moon, revealing how best to observe it, and what you should look out for.

For advice on exploring the Moon whatever its phase, read our guide on how to observe the Moon.

6 ways to enjoy a full Moon

1

Watch the full Moon rise

Full Moon rising over North Tenerife by Peter Louer, Tenerife. Equipment: Canon 700D, 55-250mm lens.
Full Moon rising over North Tenerife by Peter Louer, Tenerife. Equipment: Canon 700D, 55-250mm lens.

It’s all too easy to take the rising full Moon for granted, only stopping to watch if you glimpse it inadvertently rather than treating it as a celestial event in its own right.

Yet if you can get to an observing site with an unobstructed horizon on a clear evening, there are many fascinating phenomena to catch sight of as the Moon climbs.

One that tends to stops most people in their tracks is the famous ‘Moon illusion’, which makes the rising lunar disc appear larger than when it’s higher in the sky.

Moonset at Ilhéus by Aladin Kinach Rodrigues, Ilhéus, Bahia, Brazil. Equipment: Canon T3, EF75-300mm f/4-5.6.
Moonset at Ilhéus by Aladin Kinach Rodrigues, Ilhéus, Bahia, Brazil. Equipment: Canon T3, EF75-300mm f/4-5.6.

But there’s also the ‘rippling’ edge and ‘flattening’ of the Moon’s disc, caused by atmospheric refraction, to look out for – particularly with a small telescope or good binoculars.

And if the skies are really clear, watching the reddened full Moon rising below the pink ‘Belt of Venus’ – back-scattered light from the setting Sun at twilight – can make for wonderful observing memories.

2

See the Moon’s ray-ejecta systems

Copernicus Crater by Peter Louer, Tenerife. Equipment: Canon EOS 700D at Prime focus, Meade 105ETX.
Copernicus Crater by Peter Louer, Tenerife. Equipment: Canon EOS 700D at Prime focus, Meade 105ETX.

There’s one type of lunar feature that really dazzles during a full Moon. They’re known as ray ejecta systems and they make fantastic imaging targets.

They appear as bright streaks radiating from certain craters and consist of the material thrown out from the violent impacts that formed these surface scars.

A DSLR attached to a lens or small telescope, with a focal length of around 300-400mm, will easily pick up the more extensive ray systems, such as that of Tycho.

A webcam or high frame rate CCD camera combined with a modest telescope is an ideal setup for capturing the wonderful complexity and unusual shapes of the ray ejecta around craters such as Copernicus (see above) and Proclus.

3

Explore the edge of the Moon

Thanks to lunar libration we can observe slightly more than half of the Moon’s surface. Credit: Pete Lawrence
Thanks to lunar libration we can observe slightly more than half of the Moon’s surface. Credit: Pete Lawrence

As the Moon orbits Earth it doesn’t always show the exact same face to us. In fact, it appears to wobble during the course of its orbit so that otherwise-invisible parts of the lunar limb rotate towards us, while other parts are rotated away.

This allows us to glimpse a little more of the Moon’s globe than just a single, static hemisphere. This phenomenon is known as lunar libration and it can bring into view craters and other surface features that aren’t always visible.

Mare Humboldtianum approaching, then disappearing, over the Moon’s limb. Credit: Pete Lawrence
Mare Humboldtianum approaching, then disappearing, over the Moon’s limb during libration. Credit: Pete Lawrence

So don’t discount getting your telescope out on the nights around the full Moon when the gibbous Moon is shining brightly.

Although it might seem as if there’s only a narrow strip of terminator  to observe, there may be a feature that libration has brought into a good position to study.

Features that benefit from libration include the Pythagoras and Grimaldi craters and the Mare Humboldtianum.

4

See the 22° halo

A halo around the Moon captured by Mohammed Aissa Moussa from Ghardaia, Algeria. Mohammed used a Canon EOS 5D Mark II DSRL camera and 15mm fisheye lens.
A halo around the Moon captured by Mohammed Aissa Moussa from Ghardaia, Algeria. Mohammed used a Canon EOS 5D Mark II DSRL camera and 15mm fisheye lens.

On most nights high, wispy, clouds drifting overhead would quickly curtail an imaging or observing session.

But at full Moon, as well as when our nearest neighbour is showing its larger ‘gibbous’ phases, bright moonlight streaming down through such clouds can occasionally create beautiful haloes and other atmospheric phenomena that make intriguing and sometimes elusive celestial quarries for observers and astrophotographers alike.

One atmospheric phenomenon you may see around the time of full Moon is a bright ring of light around the lunar disc.

It’s an ice halo known as the 22° halo – due to its angular radius on the sky being 22° – and is caused by ice crystals suspended within high clouds refracting the light of the Moon.

Moonlight shining through ice crystals in clouds may result in the 22° lunar halo. Credit: Will Gater.
Moonlight shining through ice crystals in clouds may result in the 22° lunar halo. Credit: Will Gater.

You can generally confirm what you’re seeing is the 22° halo by holding your outstretched hand at arm’s length, while placing the tip of your little finger over the lunar disc.

If the tip of your thumb is almost reaching the halo then you can be confident that it’s the 22° halo you’ve spotted.

Sometimes the 22° halo can be very faint – requiring you to block out the bright lunar disc with your outstretched hand to see – whereas other times it can be absolutely unmistakable, even against the glare of the Moon.

Another striking phenomenon, although this time created by diffraction through water droplets rather than ice within clouds, is the lunar corona, which appears as a spectacular series of concentric coloured bands around the Moon.

5

Search for a moondog

Moondogs are caused by ice crystals and appear as bright spots on the lunar halo. Credit: Will Gater.
Moondogs are caused by ice crystals and appear as bright spots on the lunar halo. Credit: Will Gater.

Perhaps the atmospheric phenomena that are the most rewarding to catch around the time of full Moon are the ethereal apparitions known as ‘moondogs’ or ‘paraselenae’.

These are just like the ‘sundogs’ that are seen during the daytime (read our guide to daytime astronomy) but tend to be much more difficult to spot due to their often being considerably fainter.

Just like the 22° halo, moondogs are formed by the refraction of moonlight through ice crystals within wispy clouds.

If the clouds are thin or scattered enough to allow bright stars to be seen around them they can be a truly exquisite sight as well as being a fantastic target for astrophotographers.

6

Observe a lunar eclipse

Lunar Eclipse (28/09/2015) by Scott Phillips, Wales, UK.
Lunar Eclipse (28/09/2015) by Scott Phillips, Wales, UK. Equipment: Skywatcher Skymax 127 EQ-5, Canon 450d, Backyard EOS

If you’re still not convinced about the merits of observing around the time of full Moon then maybe the magic of a celestial phenomenon that can only occur at this time will finally win you over. We’re talking, of course, about a total lunar eclipse.

Granted, they’re not exactly monthly events, but there’s no denying that the slow and serene progress of the Earth’s shadow across the lunar disc – with the full Moon turning from blazing silver to a soft orangey-red – makes for one of nature’s greatest shows.

It’s worth watching these events just to see the fainter stars emerge during totality, when the sky darkens as the light of the full Moon is dimmed. Find out which eclipses are coming up in our guide to the next eclipse.

Pictures of a full Moon

Below is a selection of images of the full Moon captured by astrophotographers and BBC Sky at Night Magazine readers. For lunar imaging advice, read our guide on how to photograph the Moon.

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And don’t forget to send us your images or share them with us via Facebook, Twitter and Instagram.

The Full Moon by Tom Chitson, Woking, Surrey, UK. Equipment: SkyWatcher Explorer 130p, EQ2 Mount, Sony Cybershot DSC-W210.
The Full Moon by Tom Chitson, Woking, Surrey, UK. Equipment: SkyWatcher Explorer 130p, EQ2 Mount, Sony Cybershot DSC-W210.
Full Moon by Richard Hancock, Bideford, Devon, UK. Equipment: Skywatcher 200pds, Baader Camera Adapter, Basic Digital Camera.
Full Moon by Richard Hancock, Bideford, Devon, UK. Equipment: Skywatcher 200pds, Baader Camera Adapter, Basic Digital Camera.
Full Moon by David Duff, Stockton on Tees, UK. Equipment: Skywatcher Explorer 150P, Panasonic Lumix G10 at prime focus.
Full Moon by David Duff, Stockton on Tees, UK. Equipment: Skywatcher Explorer 150P, Panasonic Lumix G10 at prime focus.
Full Moon by Alan Stewart, Glenrothes, Fife, UK. Equipment: Skywatcher 150PL, Canon EOS400D.
Full Moon by Alan Stewart, Glenrothes, Fife, UK. Equipment: Skywatcher 150PL, Canon EOS400D.
Full Moon 14.09.11 by James Phillips, Newton Aycliffe, UK. Equiment: Meade ETX 125, Canon 300D camera connected via eye-piece
Full Moon 14.09.11 by James Phillips, Newton Aycliffe, UK. Equiment: Meade ETX 125, Canon 300D camera connected via eye-piece
Full Moon by Roger Bisgood, Norfolk, UK. Equipment: SW ED120 PRO, Canon 1000D , HEQ5 mount.
Full Moon by Roger Bisgood, Norfolk, UK. Equipment: SW ED120 PRO, Canon 1000D , HEQ5 mount.
Full Moon 9th Dec 2011 by Daniel Niblock, Larne, N.Ireland. Equipment: Skywatcher 150pl EQ3, Skywatcher Dual Axis Stepper Motor, Canon eos 450d.
Full Moon 9th Dec 2011 by Daniel Niblock, Larne, N.Ireland. Equipment: Skywatcher 150pl EQ3, Skywatcher Dual Axis Stepper Motor, Canon eos 450d.
99.8% Full, 1st August 2012, 23:00 by Steve Ward, Red Lodge, Suffolk, UK. Equipment: Canon 1000D, EQ3-2, SW ED80 Pro + 1.8 x Barlow.
99.8% Full, 1st August 2012, 23:00 by Steve Ward, Red Lodge, Suffolk, UK. Equipment: Canon 1000D, EQ3-2, SW ED80 Pro + 1.8 x Barlow.
November Full Moon From London by Chris Cormack, Wimbledon, UK. Equipment: Celestron 6SE, Canon 1100d, prime focus.
November Full Moon From London by Chris Cormack, Wimbledon, UK. Equipment: Celestron 6SE, Canon 1100d, prime focus.
July Full Moon by Chris Isherwood, Kent, UK. Equipment: Skywatcher Evostar 80ED Refractor, Canon 600D camera.
July Full Moon by Chris Isherwood, Kent, UK. Equipment: Skywatcher Evostar 80ED Refractor, Canon 600D camera.
Just Past Full Moon by Alan Kennedy, Ferryhill, County Durham. Equipment: Celestron 8
Just Past Full Moon by Alan Kennedy, Ferryhill, County Durham. Equipment: Celestron 8″ SC, Skywatcher NEQ6, SPC880NC, SPC900NC.
Full Moon Mosaic in Northumberland National Park by Stephen Charnock, Bellingham, Northumberland, UK. Equipment: Canon 60D and Orion 90mm APEX Maksutov-Cassegrain using a Baader 13mm eyepiece for eyepiece projection.
Full Moon Mosaic in Northumberland National Park by Stephen Charnock, Bellingham, Northumberland, UK. Equipment: Canon 60D and Orion 90mm APEX Maksutov-Cassegrain using a Baader 13mm eyepiece for eyepiece projection.
The Full Moon by Gavin James, Marlborough, UK. Equipment: Celestron EdgeHD 800, ASI120-MC-S.
The Full Moon by Gavin James, Marlborough, UK. Equipment: Celestron EdgeHD 800, ASI120-MC-S.
Christmas Eve Full Moon by Nicola Warner, Leicestershire, UK. Equipment: Canon 1000D DSLR, SkyWatcher 200p Dob
Christmas Eve Full Moon by Nicola Warner, Leicestershire, UK. Equipment: Canon 1000D DSLR, SkyWatcher 200p Dob
Nearly Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, Maksutov 127mm, Prime focus single shot.
Nearly Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, Maksutov 127mm, Prime focus single shot.
Full Moon by Martin Pyott, St Andrews, Fife, UK. Equipment: Skywatcher 66mm Equinox @ F6, AZ-3 mount, Canon 600D.
Full Moon by Martin Pyott, St Andrews, Fife, UK. Equipment: Skywatcher 66mm Equinox @ F6, AZ-3 mount, Canon 600D.
Full Moon Over Armagh, Northern Ireland by Patrick Hughes, Armagh, Northern Ireland. Equipment: Canon 5D MkIII, Tamron 150-600mm lens.
Full Moon Over Armagh, Northern Ireland by Patrick Hughes, Armagh, Northern Ireland. Equipment: Canon 5D MkIII, Tamron 150-600mm lens.
Full Moon by Keith Sale, Stockport, UK. Equipment: Panasonic Lumix Tz 60 hand held.
Full Moon by Keith Sale, Stockport, UK. Equipment: Panasonic Lumix Tz 60 hand held.
Full Moon of July 2016 by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Neq3-2, Nikon D5300.
Full Moon of July 2016 by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Neq3-2, Nikon D5300.
3 Days around the Full Moon by John Foster, Plymouth, UK. Equipment: Skywatcher 102/1000 refractor, Nikon D3200, EQ3 mount.
3 Days around the Full Moon by John Foster, Plymouth, UK. Equipment: Skywatcher 102/1000 refractor, Nikon D3200, EQ3 mount.
Cloudy Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, 75-300mm
Cloudy Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, 75-300mm
Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, 75-300mm
Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, 75-300mm
Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, Maksutov 127mm, Prime focus single shot
Perigee-syzygy Full Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK. Equipment: Canon 600D, Maksutov 127mm, Prime focus single shot
Full Moon Comparison by Houssem Ksontini, Tunis, Tunisia. Equipment: Nikon D5300, Skywatcher 150/750 Newtonian.
Full Moon Comparison by Houssem Ksontini, Tunis, Tunisia. Equipment: Nikon D5300, Skywatcher 150/750 Newtonian.
First Full Moon of Spring near Jupiter by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK Equipment: Canon 600D, 300mm
First Full Moon of Spring near Jupiter by Sarah & Simon Fisher, Bromsgrove, Worcestershire, UK Equipment: Canon 600D, 300mm
Full Moon setting over north Tenerife by Peter Louer, Tenerife. Equipment: Canon 700D, Canon 100-400mm lens, Yougnuo 2x tele extender.
Full Moon setting over north Tenerife by Peter Louer, Tenerife. Equipment: Canon 700D, Canon 100-400mm lens, Yougnuo 2x tele extender.
Full Moon rising over North Tenerife by Peter Louer, Llanito Perera, Tenerife. Equipment: Canon 700D, Canon 55-250mm lens @250mm
Full Moon rising over North Tenerife by Peter Louer, Llanito Perera, Tenerife. Equipment: Canon 700D, Canon 55-250mm lens @250mm
Full Moon in Colors by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Neq3-2 mount RA motorised, ASI224MC, IR cut filter
Full Moon in Colors by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Neq3-2 mount RA motorised, ASI224MC, IR cut filter
Full Moon by Alex Higgs, Hessle, UK. Equipment: 20x80 bincoulars, Samsung mobile phone
Full Moon by Alex Higgs, Hessle, UK. Equipment: 20×80 bincoulars, Samsung mobile phone
Full Moon by Alex Higgs, Hessle, UK. Equipment: 130EQ Celestron, Samsung J5.
Full Moon by Alex Higgs, Hessle, UK. Equipment: 130EQ Celestron, Samsung J5.
Moon by Bethan Jewell-Smitham, Swansea, Wales, UK. Equipment: Mini-Dobsonian, standard camera.
Moon by Bethan Jewell-Smitham, Swansea, Wales, UK. Equipment: Mini-Dobsonian, standard camera.
Moon by Martin, Portsmouth, UK. Equipment: Sony a300, 70-300mm Tamaron lens no filters.
Moon by Martin, Portsmouth, UK. Equipment: Sony a300, 70-300mm Tamaron lens no filters.
The Moon by Iain Pugh-Wood, Gloucester, UK. Equipment: Skywatcher Explorer 130PM Reflector, Orion Starshoot Solar System Colour Imager IV
The Moon by Iain Pugh-Wood, Gloucester, UK. Equipment: Skywatcher Explorer 130PM Reflector, Orion Starshoot Solar System Colour Imager IV
Jupiter & Moon by Ronan Monaghan, Belleek, N. Ireland. Equipment: Microsoft Lifecam Webcam, Skywatcher 150p
Jupiter & Moon by Ronan Monaghan, Belleek, N. Ireland. Equipment: Microsoft Lifecam Webcam, Skywatcher 150p
The Moon by Bill McSorley, Leeds, UK. Equipment: SW 150P Newtonian, EQ5 GoTo Mount, QHY8L OSC cooled ccd camera.
The Moon by Bill McSorley, Leeds, UK. Equipment: SW 150P Newtonian, EQ5 GoTo Mount, QHY8L OSC cooled ccd camera.
Blue Moon 2 by Adam Pettifer, Epsom, UK. Equipment: SkyWatcher 130p, EQ-2 mount, iPhone 4 camera.
Blue Moon 2 by Adam Pettifer, Epsom, UK. Equipment: SkyWatcher 130p, EQ-2 mount, iPhone 4 camera.
The Moon by Bill McSorley, Leeds, UK. Equipment: SW ST80 Refractor, EQ5 GoTo Mount, QHY5l-ll ccd camera for Luminance, QHY8L ccd camera for Colour.
The Moon by Bill McSorley, Leeds, UK. Equipment: SW ST80 Refractor, EQ5 GoTo Mount, QHY5l-ll ccd camera for Luminance, QHY8L ccd camera for Colour.
Moon 13th May 2015 by Mark Walker, Gloucester, UK. Equipment: Canon EOS1100D T-Ring mounted, Skywatcher 200p Dobsonian.
Moon 13th May 2015 by Mark Walker, Gloucester, UK. Equipment: Canon EOS1100D T-Ring mounted, Skywatcher 200p Dobsonian.
Blue moon over Bedfordshire - 31st July 2015 by Roger Skillin, Cambridgeshire, UK. Equipment: Nikon D610, Sigma 120-400mm APO VR lens
Blue moon over Bedfordshire – 31st July 2015 by Roger Skillin, Cambridgeshire, UK. Equipment: Nikon D610, Sigma 120-400mm APO VR lens
Blue Moon by Lee Tilley, Hounslow, UK. Equipment: Canon SX60
Blue Moon by Lee Tilley, Hounslow, UK. Equipment: Canon SX60
Blue Moon by Ollie Turrell, Connor Downs, Cornwall, UK. Equipment: Nikon Coolpix L120
Blue Moon by Ollie Turrell, Connor Downs, Cornwall, UK. Equipment: Nikon Coolpix L120
Moon 25th 11 2015 by Richard Wykes, Northamptonshire, UK. Equipment: Skywatcher ED80, Canon 1000D, manually tracked, Vixen Super Polaris EQ mount.
Moon 25th 11 2015 by Richard Wykes, Northamptonshire, UK. Equipment: Skywatcher ED80, Canon 1000D, manually tracked, Vixen Super Polaris EQ mount.
The Moon by Kevin Jackson, UK. Equipment: Sky-Watcher Equinox Pro 80ED, QHY5L-IIM, 0.5x Reducer.
The Moon by Kevin Jackson, UK. Equipment: Sky-Watcher Equinox Pro 80ED, QHY5L-IIM, 0.5x Reducer.
The Moon by David Keep, East Malling, Kent, UK. Equipment: Canon 700D, 600mm lens.
The Moon by David Keep, East Malling, Kent, UK. Equipment: Canon 700D, 600mm lens.
The Moon - 09th May 2017 by Chris Campbell, Widnes, Cheshire, UK. Equipment: Skywatcher 130/900, RA motor drive, Adapted Microsoft HD3000 Webcam, 2x Barlow
The Moon – 09th May 2017 by Chris Campbell, Widnes, Cheshire, UK. Equipment: Skywatcher 130/900, RA motor drive, Adapted Microsoft HD3000 Webcam, 2x Barlow
Moon - Mosaic by Ronald Piacenti Junior, Brasilia-DF, Brazil. Equipment: Celestron C6 Schimt Cassigrain XLT, 0.63 focal reducer, HEQ5 Pro mount, ZWO AS174MC camera, optilong cls filter
Moon – Mosaic by Ronald Piacenti Junior, Brasilia-DF, Brazil. Equipment: Celestron C6 Schimt Cassigrain XLT, 0.63 focal reducer, HEQ5 Pro mount, ZWO AS174MC camera, optilong cls filter
Tungsten Moon by Steve Brown, Stokesley, N. Yorkshire, UK. Equipment: Canon 600D, Celestron NexStar 6SE.
Tungsten Moon by Steve Brown, Stokesley, N. Yorkshire, UK. Equipment: Canon 600D, Celestron NexStar 6SE.
Dark Moon by Alex Higgs, Hessle, E. Yorkshire, UK. Equipment: 20x80 Binoculars, Smartphone.
Dark Moon by Alex Higgs, Hessle, E. Yorkshire, UK. Equipment: 20×80 Binoculars, Smartphone.