How to observe a crescent Moon

A crescent Moon is a spectacular sight. Here are some of the top features to see on a waxing and waning crescent.

Crescent Moon Nick Jackson, Doncaster, 9 March 2019 Equipment: Nikon P900 digital bridge camera

A crescent Moon is one of the most spectacular sights to see in the night sky. Not only does it look beautiful, but a closer view through binoculars or a telescope will reveal the shadows of craters and other features like lunar maria, emphasised by the terminator (the line dividing the lit and unlit portions of the Moon).

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The whole lunar cycle lasts around 29 days, and during that time it passes through several stages known as the phases of the Moon.

The phases of the Moon. Credit: Yaorusheng / Getty Images
The phases of the Moon. Credit: Yaorusheng / Getty Images

During a lunar month, the Moon goes from new Moon, through the waxing crescent phase up to first quarter when the Moon’s disc appears half illuminated.

As more of the Moon is illuminated by the Sun over time, this is known as the waxing gibbous phase, which occurs until full Moon, when the lunar disc is fully illuminated.

Then, the cycle reverses and goes from full Moon, through a waning gibbous phase until last quarter when, again, the lunar disc is half-illuminated (but this time on the opposite side).

Slowly, less and less of the Moon’s disc is illuminated during the waning crescent phase, until we’re back to new Moon and the cycle begins again.

The waxing crescent phase lasts from about day 1 to day 6 of the lunar cycle, and the waning crescent phase lasts from about day 23 to day 29.

The phases of the Moon. Þ The inner circle shows what the Moon looks like seen from above its north pole, while the outer circle shows the phase we see from Earth at that time. Credit: BBC Sky at Night Magazine
The phases of the Moon. The inner circle shows what the Moon looks like seen from above its north pole, while the outer circle shows the phase we see from Earth at that time. Credit: BBC Sky at Night Magazine

Observing the crescent Moon

These crescent phases make for a great time during which to get a good look at our lunar neighbour, and if you can manage to observe the Moon every night – weather permitting – you’ll notice the terminator creeping across the lunar disc as more – or less – of the Moon is illuminated by the Sun.

Below we’ll reveal what you can see on the Moon during its crescent phase, and specific features or lunar phenomena to look out for.

For more advice on exploring the wonders of the Moon – whatever its phase – read our guide on how to observe the Moon and the best features on the Moon.

If you want to capture the Moon’s beauty, read our guides on how to photograph the Moon and how to draw the Moon.

Observing a waxing crescent

Day 3: Earthshine

A thin crescent Moon is a beautiful sight hanging in the west after sunset. But does the dark portion seem to be gently glowing? Binoculars or a small telescope will confirm that it is.

This ghostly illumination comes from sunlight reflected off Earth and is appropriately known as Earthshine. This sight is often called: “the new Moon in the old Moon’s arms.”

Crescent Moon and Earthshine by Ron G, Stafford, UK. Equipment: Canon 1200D, tripod, Tamron 70-300mm lens
Crescent Moon and Earthshine by Ron G, Stafford, UK. Equipment: Canon 1200D, tripod, Tamron 70-300mm lens

The dominant feature of the sunlit crescent is a mare – a large, dark plain on the Moon’s surface – called Mare Crisium.

Due to the very slow rolling motion of the Moon, known as lunar libration, Mare Crisium sometimes appears almost at the edge (the lunar limb), while at other times it’s slightly farther in.

Regardless of its position you can explore the mare’s western shore for low, sinuous ridges (‘wrinkle ridges’) and small craters called ‘craterlets’.

These include Picard, which is just 23km (14 miles) across. Just north, along the terminator, is the larger 126km (79 mile) Cleomedes. You might be able to spot the central peak inside it.

Day 5: Craters Theophilus, Cyrillus and Catharina

Moon craters Theophilus, Cyrillus and Catharina. Credit: Pete Lawrence.
Credit: Pete Lawrence.

Several great trios of craters are visible on the Moon, and tonight you can explore one of them.

On the terminator, just below the middle of the Moon, is the magnificent chain of Theophilus, Cyrillus and Catharina – their ages increase as you follow them from north to south.

All are 100km (62 miles) across and they’re easy to find, lying just west of another large lunar mare – Mare Nectaris.

Theophilus, with its terraced walls and central peak, is the most spectacular of the three. Its southwestern rim covers neighbouring Cyrillus.

Explore the overlap, and look for a small crater inside Cyrillus’s western wall. Below Cyrillus is Catharina. The oldest of the three craters, it has disintegrated walls and smaller craters superimposed on it.

Observing a waning crescent

Day 24: Sinus Iridum

Moon crater Sinus Iridum. Credit: Pete Lawrence
Credit: Pete Lawrence

Perched on the northwestern edge of Mare Imbrium is Sinus Iridum, which in Latin means ‘Bay of Rainbows’. Sinus Iridum is actually a 236km (148 mile) crater, but it was flooded with lava after the impact that created it.

Standing out in sharp relief around Sinus Iridum are four craters some 40km (25 mile) across. Bianchini is dug into Iridum’s northern wall, and Sharp and Mairan lie to the west.

Above Sinus Iridum, embedded in another mare (Mare Frigoris), is the fourth crater – Harpalus. You should also take the time to explore the Jura Mountains, which shape the northern half of Iridum.

Then return to Mare Humorum in the southwest of the Moon. Below it, to the southeast, is a very elongated crater called Schiller. About 180km long by 70km wide (113 by 44 miles), Schiller’s appearance could be the result of a low-angle impact.

Day 26: Schickard, Wargentin and Phocylides 

Credit: Pete Lawrence
Credit: Pete Lawrence

This is a challenging phase to observe because the Moon is usually low and large features aren’t easy to locate.

Near the centre of the Moon’s edge (limb) is the 172km (108 mile) basin Grimaldi, which has a dark floor due to the lava that’s flowed across it in the past. You can see it with binoculars.

To the east is the vast Oceanus Procellarum (‘Ocean of Storms’ in Latin) – at 2,500km across it’s the Moon’s biggest mare. On its western side is a white swirly patch called Reiner Gamma.

It’s unusual because it has a magnetic field all of its own. In the southwest, numerous craters including Schickard, Wargentin and Phocylides appear elongated because of the curvature of the Moon – an effect known as ‘foreshortening’.

Pictures of the crescent Moon

Below is a selection of images of crescent Moons captured by astrophotographers and BBC Sky at Night Magazine readers. For lunar imaging advice, read our guide on how to photograph the Moon or our beginner’s guide to astrophotography.

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

Crescent Moon Nick Jackson, Doncaster, 9 March 2019 Equipment: Nikon P900 digital bridge camera
Crescent Moon
Nick Jackson, Doncaster, 9 March 2019
Equipment: Nikon P900 digital bridge camera
My first moon shot! Philip Ditchfield, Preston, UK. Equipment: Celestron Nexstar 6 SE, Konica Minolta Dynax 5d, T ring, T ring Adaptor
My first moon shot! Philip Ditchfield, Preston, UK. Equipment: Celestron Nexstar 6 SE, Konica Minolta Dynax 5d, T ring, T ring Adaptor
Moon Mosiac by Ben Murray, Preston, UK. Equipment: SPC 900, Celestron Nexstar 127SLT
Moon Mosiac by Ben Murray, Preston, UK. Equipment: SPC 900, Celestron Nexstar 127SLT
Blue Moon by Yann, Johannesburg, South Africa. Equipment: LX200 GPS 8
Blue Moon by Yann, Johannesburg, South Africa. Equipment: LX200 GPS 8″, Nikon D200, Lunar Filter
Angel's Moon by Mike Goodfellow, Crawley, West Sussex, UK. Equipment: Meade 127mm ED APO, Cannon 450D, Berlebach tripod, Deluxe Giro Mount.
Angel’s Moon by Mike Goodfellow, Crawley, West Sussex, UK. Equipment: Meade 127mm ED APO, Cannon 450D, Berlebach tripod, Deluxe Giro Mount.
Crescent Moon by Paul Bailey, Chester, Equipment: Sky-watcher 200p newtonian reflector, EQ5 Mount, Microsoft Lifecam Studio HD
Crescent Moon by Paul Bailey, Chester, Equipment: Sky-watcher 200p newtonian reflector, EQ5 Mount, Microsoft Lifecam Studio HD
Crescent Moon March 2012 by Martin Lacey, Heanor, Derbyshire, UK. Equipment: Skywatcher EQ5 8
Crescent Moon March 2012 by Martin Lacey, Heanor, Derbyshire, UK. Equipment: Skywatcher EQ5 8″ Reflector, Teknika Digital Camera, 25 mm lens.
Astromoon by Martin Lacey, Heanor, Derbyshire. Equipment: Skywatcher eq5 200mm, 17mm lens, 2x Barlow, Technika camera.
Astromoon by Martin Lacey, Heanor, Derbyshire. Equipment: Skywatcher eq5 200mm, 17mm lens, 2x Barlow, Technika camera.
Crescent Moon Mosaic by Luke Oliver, Bedford, UK. Equipment: SPC 900NC, 2x Barlow Lens, Baader IR-Pass (685nm) Filter, Sky-Watcher Explorer-200, Registax 6.
Crescent Moon Mosaic by Luke Oliver, Bedford, UK. Equipment: SPC 900NC, 2x Barlow Lens, Baader IR-Pass (685nm) Filter, Sky-Watcher Explorer-200, Registax 6.
Crescent Moon Mosaic 16 December 2012 by Grant Ritchie, Edinburgh, Scotland. Equipment: Celestron NexStar 5se, DFK21AU04.AS CCD.
Crescent Moon Mosaic 16 December 2012 by Grant Ritchie, Edinburgh, Scotland. Equipment: Celestron NexStar 5se, DFK21AU04.AS CCD.
Moon by Brian R Bugler, Worth Matravers. Equipment: Canon 5D mk.III, Celestron Nexstar 127
Moon by Brian R Bugler, Worth Matravers. Equipment: Canon 5D mk.III, Celestron Nexstar 127
Crescent Moon by Felisberto Soares, Porto, Portugal. Equipment: Canon EOS 500D, tripod, Helios 135mm f2.8 manual lens.
Crescent Moon by Felisberto Soares, Porto, Portugal. Equipment: Canon EOS 500D, tripod, Helios 135mm f2.8 manual lens.
St. Patrick's Moon by Brian R Bugler, Worth Matravers, Dorset. Equipment: Canon 5D mkIII, Celestron 127SLT.
St. Patrick’s Moon by Brian R Bugler, Worth Matravers, Dorset. Equipment: Canon 5D mkIII, Celestron 127SLT.
Spring Moon by Tom Howard, Crawley, Sussex. Equipment: Nikon D7000, Meade 5000 127mm refractor, EQ6.
Spring Moon by Tom Howard, Crawley, Sussex. Equipment: Nikon D7000, Meade 5000 127mm refractor, EQ6.
Moon Mosaic 16 April 2013 by Aprill Harper, Blunham, Bedfordshire. Equipment: Meade LX90-ACF 10
Moon Mosaic 16 April 2013 by Aprill Harper, Blunham, Bedfordshire. Equipment: Meade LX90-ACF 10″, Samsung NX1000 Camera
Lunar Crescent 2nd September 2013 by Aprill Harper, Blunham, Bedfordshire. Equipment: SkyWatcher 8
Lunar Crescent 2nd September 2013 by Aprill Harper, Blunham, Bedfordshire. Equipment: SkyWatcher 8″ Dobsonian, Samsung NX1000 Camera
Crescent Moon 2014 by Alan Stewart, Glenrothes. Equipment: Orion Starshoot IV
Crescent Moon 2014 by Alan Stewart, Glenrothes. Equipment: Orion Starshoot IV
Midday Crescent by Nartib Rogers, Chalfont St Peter, UK. Equipment: Pentax KR5, SMC Pentax 55-300mm zoom @300mm
Midday Crescent by Nartib Rogers, Chalfont St Peter, UK. Equipment: Pentax KR5, SMC Pentax 55-300mm zoom @300mm
Moon at Twilight by David Hallam. Equipment: Celestron Nexstar SLT127, Cannon EOS 1100.
Moon at Twilight by David Hallam. Equipment: Celestron Nexstar SLT127, Cannon EOS 1100.
35% Moon Mosaic by Jarrod Bennett, Mutxamel, Spain. Equipment: Skywatcher 150PL, ASI120mm, Baader Red filter.
35% Moon Mosaic by Jarrod Bennett, Mutxamel, Spain. Equipment: Skywatcher 150PL, ASI120mm, Baader Red filter.
Waxing Crescent Moon (Laterally Inverted) by Callum Pennington, St. Helens, Merseyside. Equipment: Sky-Watcher BK 1309 EQ2 130mm Newtonian Reflector, super 25mm eyepiece, HookUpz Universal Adapter, Smartphone.
Waxing Crescent Moon (Laterally Inverted) by Callum Pennington, St. Helens, Merseyside. Equipment: Sky-Watcher BK 1309 EQ2 130mm Newtonian Reflector, super 25mm eyepiece, HookUpz Universal Adapter, Smartphone.
Crescent Moon by Daniel Orchard, Melksham, Wiltshire. Equipment: Skywatcher explorer 200p, EQ5 unguided Ra motor driven, Nikon D50 at prime focus.
Crescent Moon by Daniel Orchard, Melksham, Wiltshire. Equipment: Skywatcher explorer 200p, EQ5 unguided Ra motor driven, Nikon D50 at prime focus.
Crescent Moon by Lee Tilley, Hounslow UK. Equipment: Canon Powershot sx60
Crescent Moon by Lee Tilley, Hounslow UK. Equipment: Canon Powershot sx60
Waxing Crescent by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, 300mm
Waxing Crescent by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, 300mm
Waxing Crescent Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Maksutov 127mm telescope, Prime focus single shot.
Waxing Crescent Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Maksutov 127mm telescope, Prime focus single shot.
Moon Waning Crescent by Paul Licorish, Wembley Stadium, London. Equipment: Canon 6d, Celestron Advanced VX 8
Moon Waning Crescent by Paul Licorish, Wembley Stadium, London. Equipment: Canon 6d, Celestron Advanced VX 8″ Edge-HD
Moonish Behavior by Jaspal Chadha, London. Equipment: Skywatcher Esprit 100ED, Ioptron 45 Pro, Canon D550 DSLR
Moonish Behavior by Jaspal Chadha, London. Equipment: Skywatcher Esprit 100ED, Ioptron 45 Pro, Canon D550 DSLR
Lovely Luna by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Maksutov 127mm.
Lovely Luna by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Maksutov 127mm.
The Moon by Jack Reeves (aged 14), UK. Equipment: Celestron Astromaster 90 AZ mount, smartphone.
The Moon by Jack Reeves (aged 14), UK. Equipment: Celestron Astromaster 90 AZ mount, smartphone.
Waxing Crescent Moon by John Foster, Plymouth. Equipment: D3200, Skywatcher 130 reflector
Waxing Crescent Moon by John Foster, Plymouth. Equipment: D3200, Skywatcher 130 reflector
Waxing Crescent Moon over Gateshead by David Blanchflower, Newcastle upon Tyne. Equipment: Canon 1200D camera, Canon EF-S 75-300mm lens, tripod.
Waxing Crescent Moon over Gateshead by David Blanchflower, Newcastle upon Tyne. Equipment: Canon 1200D camera, Canon EF-S 75-300mm lens, tripod.
Dusk by Lori-Ann Foley, Jersey, Channel Islands. Equipment: Canon EOS 1200D
Dusk by Lori-Ann Foley, Jersey, Channel Islands. Equipment: Canon EOS 1200D
Waxing Crescent Moon by Paul Cotton, Lincolnshire. Equipment: Celestron C9.25 SCT, 6.3 focal reducer, Canon 1100d DSLR, Skywatcher NEQ 6pro mount
Waxing Crescent Moon by Paul Cotton, Lincolnshire. Equipment: Celestron C9.25 SCT, 6.3 focal reducer, Canon 1100d DSLR, Skywatcher NEQ 6pro mount
Waxing Crescent Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Mak 127mm
Waxing Crescent Moon by Sarah & Simon Fisher, Bromsgrove, Worcestershire. Equipment: Canon 600D, Mak 127mm
49.2% Waxing Crescent Moon by Jason Clogg, Rayleigh, Essex, UK. Equipment: Skywatcher 130P, Canon 450D
49.2% Waxing Crescent Moon by Jason Clogg, Rayleigh, Essex, UK. Equipment: Skywatcher 130P, Canon 450D
Crescent Moon by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Nikon D5300
Crescent Moon by Houssem Ksontini, Tunis, Tunisia. Equipment: Skywatcher 150/750, Nikon D5300
Winter Crescent Moon by Martin Davies, Bridport, Dorset. Equipment: Celestron Travel Scope 70, iPhone 5s.
Winter Crescent Moon by Martin Davies, Bridport, Dorset. Equipment: Celestron Travel Scope 70, iPhone 5s.
The Moon by Chris Campbell, Cheshire. Equipment: HD3000 webcam, Skywatcher 130/900, EQ2
The Moon by Chris Campbell, Cheshire. Equipment: HD3000 webcam, Skywatcher 130/900, EQ2
Waxing Gibbous by Graham, Western Australia. Equipment: Nikon D7200, Sigma 150-600mm f5-6.3 Sport
Waxing Gibbous by Graham, Western Australia. Equipment: Nikon D7200, Sigma 150-600mm f5-6.3 Sport
Crescent Moon 30/05/2017 by Clemens Unger, Mornington, Australia. Equipment: Nikon D7000, Russian built MTO 1100/10.5 Maksutov lens.
Crescent Moon 30/05/2017 by Clemens Unger, Mornington, Australia. Equipment: Nikon D7000, Russian built MTO 1100/10.5 Maksutov lens.
Morning Moon by Robert Walker, Santorini. Equipment: Nikon p520
Morning Moon by Robert Walker, Santorini. Equipment: Nikon p520
The Moon by Ronald Piacenti Junior, Norma Observatory, Brasilia, DF, Brazil. Equipment: Celestron C6 XLT, HEQ5 Pro mount, ASI74 MC camera, Celestron focal reducer 0.63
The Moon by Ronald Piacenti Junior, Norma Observatory, Brasilia, DF, Brazil. Equipment: Celestron C6 XLT, HEQ5 Pro mount, ASI74 MC camera, Celestron focal reducer 0.63
Waning Crescent Moon by Fernando Oliveira De Menezes, New York. Equipment: Esprit 150 ED, Zwo asi 1600mm cooled
Waning Crescent Moon by Fernando Oliveira De Menezes, New York. Equipment: Esprit 150 ED, Zwo asi 1600mm cooled
3.2% Moon After Rise by Alex, Hessle, UK. Equipment: 20x80 binoculars and Samsung mobile phone
3.2% Moon After Rise by Alex, Hessle, UK. Equipment: 20×80 binoculars and Samsung mobile phone
Crescent Moon by Alex Higgs, Hessle, UK. Equipment: 20x80 binoculars and mobile phone
Crescent Moon by Alex Higgs, Hessle, UK. Equipment: 20×80 binoculars and mobile phone
Moon by Ronald Piacenti Jr, Brasilia-DF, Brazil. Equipment: Celestron C6, with skywatcher AllView mount, ASI 174 Color
Moon by Ronald Piacenti Jr, Brasilia-DF, Brazil. Equipment: Celestron C6, with skywatcher AllView mount, ASI 174 Color
Moon by Tony Moss, Downham Market, Norfolk. Equipment: Tal 200k Telescope, G2 Lumix Camera, GTA Goto Mount, Homemade Wooden Pier
Moon by Tony Moss, Downham Market, Norfolk. Equipment: Tal 200k Telescope, G2 Lumix Camera, GTA Goto Mount, Homemade Wooden Pier
Crescent Moon by Tom Howard, Crawley, Sussex. Equipment: Nikon D7000 DSLR, TS-Optics 65mm quad refractor, Nikon TC-14E teleconverter.
Crescent Moon by Tom Howard, Crawley, Sussex. Equipment: Nikon D7000 DSLR, TS-Optics 65mm quad refractor, Nikon TC-14E teleconverter.
New Moon and Aldebaran by Martin Marthadinata, Tosari, Bromo Tengger Semeru National Park, Indonesia. Equipment: Nikon D5000, Nikkor lens 70-300vr
New Moon and Aldebaran by Martin Marthadinata, Tosari, Bromo Tengger Semeru National Park, Indonesia. Equipment: Nikon D5000, Nikkor lens 70-300vr