The Moon will pass close to
the Sun and become lost in the its glare for a few days.

The Moon’s orbital motion
carries it around the Earth once every four weeks, and as a result its phases cycle from
new moon, through first quarter, full moon and last quarter, back to new moon
once every 29.5 days.

This motion also means that the Moon travels more than 12° across
the sky from one night to the next, causing it to rise and set nearly an hour
later each day. More information about the Moon’s phases is available
here.

At new moon, the Earth, Moon and Sun all lie in a roughly straight line, with
the Moon in the middle, appearing in front of the Sun’s glare. In this
configuration, we see almost exactly the opposite half of the Moon to that
which is illuminated by the Sun, making it doubly unobservable because the side
we see is unilluminated.

Observing the Moon in the days after new moon

Over coming days, the Moon will become
visible in the late afternoon and dusk sky as a waxing crescent which sets soon
after the Sun. By first quarter, in a week’s time, it will be visible until
around midnight.

Its daily progress is charted below, with all times are given in
Los Angeles local time.

A thin crescent

The months around the spring equinox –

March and April in the northern hemisphere

– present the best opportunity to see a very thin crescent Moon
immediately after sunset in the days following new moon.

This comes about because the Moon appears higher in the dusk sky sooner
after new moon in the spring months as compared to other times of year.

At all times, the Moon lies close to a line across the sky
called the ecliptic, which is shown in yellow in the planetarium above. This line
traces the path that the Sun takes through the zodiacal constellations every year, and
shows the plane of the Earth’s orbit around the Sun. Since all the planets circle the
Sun in almost exactly the same plane, they too move across the sky following the same line.

When the Moon is widely separated from the Sun, it is separated from it
along the line of the ecliptic. But, at different times of year, the ecliptic meets the horizon
at different angles at sunrise. This means that a
certain number of days after new moon, the Moon appears at different
altitudes above the horizon at different times of year.

At sunset, the ecliptic makes its steepest angle to the horizon at the spring equinox – in March
in the northern hemisphere, and in September in the southern hemisphere. Conversely, it meets the horizon at its
shallowest angle at the autumn equinox. And so, very thin crescent moons are most visible in the evening sky
in the spring.

The inclination of the ecliptic plane to the horizon at Los Angeles varies between 79° (sunset at the spring equinox) and 32° (sunset at the autumn equinox). On November 30, the ecliptic is inclined at 43° to the western sunset horizon.

The exact moment of new moon

At the moment of closest approach, it will pass within 4°34′ of the Sun, in the constellation Scorpius.

The celestial coordinates of the Sun and Moon will be:

The coordinates above are given in J2000.0.

The sky
on 30 Nov 2024

Warning

Never attempt to point a pair of binoculars or a telescope at an object close to the Sun. Doing so
may result in immediate and permanent blindness.

Source

The circumstances of this event were computed using the DE430 planetary ephemeris published by the Jet Propulsion Laboratory (JPL).

This event was automatically generated by searching the ephemeris for planetary alignments which are of interest to amateur astronomers, and the text above was generated based on an estimate of your location.

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Image credit

Simulated image courtesy of Tom Ruen.