Have you ever wondered at what stage you can see the new crescent moon?
The next new moon will occur on Saturday August 11th 2018 at 09:58 GMT/UT or
10:58 BST, marking the start of lunation number 1183.
The timing of the August new moon means that sightings of the crescent moon
on Saturday August 11th are possible for observers with conventional,
amateur-sized telescopes from the eastern Pacific Ocean region, in particular,
the Galapagos Islands area. A sighting with the naked-eye under excellent conditions
may be possible from most of French Polynesia except the south-eastern part, the
Cook Islands, Samoa and Tonga later the same day. Easy sightings of the crescent
moon should be possible on Sunday August 12th from most of the world with the
exception of New Zealand, Japan, the north-western Pacific Ocean region, the
northern half of Asia, northern Europe including most of the British Isles,
Iceland and Greenland. These exceptions will have to wait until Monday August
13th to make their sightings. We would therefore ask observers to make their
sightings of the new crescent Moon between August 11th and August 13th and
report them to us.
If you go out just after sunset over the three or four days following the
instant of new moon and have a look low in the western half of the sky near
where the Sun set, you can try and observe the new crescent moon.
You can make the observation with just your eyes or with binoculars or
a telescope. Never look at the Sun directly
or through binoculars or a telescope as you will damage your eyesight.
If you are going to use binoculars or a telescope to find the new
crescent moon, you must make sure the Sun has set.
The crescent moon will be faint shortly after new moon but will brighten
from night to night as the crescent thickens. Cloud or aircraft vapour
trails can easily be mistaken for the Moon so be careful when making the
Scan the western horizon close to where the Sun set. If you can see the
Moon, let us know by entering your observation and location in our report
form. We need to know the date and time of your observation, what the
crescent looked like, where it was in the sky relative to the position
on the horizon where the Sun set and something about the weather
conditions and you, the observer. Even if the weather is clear and you
cannot see the Moon, let us know. A negative observation will also help
Come back to this site later in the month and you can find out what you
should have seen from your observing site. You can also sign up for an
e-mail reminder of the date and time of the next new moon so you can try
your observing skills again.
Over time, we will process your observations and try to improve the models
we use to predict the first sighting of the new crescent moon. Currently,
these predictions produce a classification for a particular date and
location ranging from A (crescent easily visible) through to F (crescent
impossible to see).
For those groups who use the first sighting of the new crescent moon in
their calendars, these predictions are very significant and mark the
beginning and end of periods of fasting and festivals.
More information on these predictions is
available on this site.
This site allows observers to look at the global visibility of the
next new moon, to check their
observations of the last new moon, to
report their observations and to
receive/stop e-mail reminders of the next new
Preliminary results will also be reported on the site when they become available.
Further information on the visibility of the new crescent moon for a specific
location can be found on our Websurf
site by selecting the Crescent Moon Visibility option from the menu.
|What we want you to do|
- Go out each evening following the day of the new moon.
- Find a westerly facing spot with a clear view of the horizon.
- Wait for the Sun to set, then look for the crescent moon in that part of the sky.
- Don't look directly at the Sun, using your naked eye, binoculars or a telescope.
- Can you see the crescent moon? Are you sure? Is it a cloud or a vapour trail?
- Make a note of where you were, the date and time of your observation, the weather conditions and whether you saw the Moon or not.
- Come to this website and report your observation.
- Try and observe the crescent moon each night until you see it, reporting each observation attempt.
- Sign up for an e-mail reminder of the next new moon and come back next month and try the same thing again.