Youngest possible lunar crescent, with the moon’s age being exactly zero when this photo was taken — at the instant of new moon – 0714 UTC on July 8, 2013. Image by Thierry Legault. Visit his website.
The ghostly image at the top of this post is a new moon. When the moon is new, its lighted half is facing entirely away from Earth, and its night face is facing us. That’s why we can’t see the moon at this time.
New moon comes on September 1 at 0903 UTC. Translate to your time zone.
This new moon will partially cover the sun, causing an annular – or “ring of fire” – eclipse over Africa on September 1. It’s final solar eclipse of 2016. The moon is too far away in its orbit to cover the sun completely, so, although the moon passes directly in front of the sun, the eclipse is not total.
Unless you see the eclipse, you won’t see the moon on September 1. A typical young moon sighting, for most people with ordinary eyesight, comes when the moon is around 24 hours from new, or more. Thus the moon will be back in the west after sunset on September 2 or 3, sweeping near the planets Jupiter and Venus.
However, with modern techniques – telescopes, filters, photography – the moon can be seen by extremely experienced observers even at the instant of new moon. That’s the case with the image at the top of this post, acquired by experienced amateur astronomer Thierry Legault in 2013. Read more about that image here.
In other words, a waning crescent seen within seconds of new moon is within the realm of possibility if special techniques and equipment are used.
On the day of new moon itself, however, most of us can’t see the moon with the eye alone for several reasons. First, at new moon, the moon rises when the sun rises. It sets when the sun sets. It crosses the sky with the sun during the day. A new moon is too close to the sun’s glare to be visible with the eye. Plus its lighted hemisphere is facing entirely away from us. It’s only as the moon moves in orbit, as its lighted hemisphere begins to come into view from Earth, that we can see it in our sky.
A new moon is more or less between the Earth and sun. Its lighted half is turned entirely away from us. Image via memrise.com.
Composite image of a 2006 solar eclipse by Fred Espenak. Read his article on the August 21, 2017 total solar eclipse, first one visible from contiguous North America since 1979.
We can’t see the new moon from Earth, except during the stirring moments of a solar eclipse. Then the moon passes in front of the sun, and the night side of the moon can be seen in silhouette against the disk of the sun. Meanwhile, if you could travel in a spaceship to the opposite side of the moon, you’d see it shining brightly in daylight.
Once each month, the moon comes all the way around in its orbit so that it is more or less between us and the sun. If the moon always passed directly between the sun and Earth at new moon, a solar eclipse would take place every month.
But that doesn’t happen every month. Instead, in most months, the moon passes above or below the sun as seen from our earthly vantage point.
Then a day or two later, the moon reappears, in the west after sunset. Then it’s a slim waxing crescent visible only briefly after sunset – what some call a young moon.
Young moon, visible a day or so after the new moon phase. A young moon is seen in the west after sunset. It’s a waxing crescent moon. Photo by Gene Porter in Georgia. On September 2, 2016, the young moon will be near Jupiter. On September 3, it’ll be near Venus.
As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.
Four keys to understanding moon phases
Where’s the moon? Waxing crescent
Where’s the moon? First quarter
Where’s the moon? Waxing gibbous
What’s special about a full moon?
Where’s the moon? Waning gibbous
Where’s the moon? Last quarter
Where’s the moon? Waning crescent
Where’s the moon? New phase
Moon in 2016: Phases, cycles, eclipses, supermoons and more
from EarthSky http://ift.tt/19T9DUm
Youngest possible lunar crescent, with the moon’s age being exactly zero when this photo was taken — at the instant of new moon – 0714 UTC on July 8, 2013. Image by Thierry Legault. Visit his website.
The ghostly image at the top of this post is a new moon. When the moon is new, its lighted half is facing entirely away from Earth, and its night face is facing us. That’s why we can’t see the moon at this time.
New moon comes on September 1 at 0903 UTC. Translate to your time zone.
This new moon will partially cover the sun, causing an annular – or “ring of fire” – eclipse over Africa on September 1. It’s final solar eclipse of 2016. The moon is too far away in its orbit to cover the sun completely, so, although the moon passes directly in front of the sun, the eclipse is not total.
Unless you see the eclipse, you won’t see the moon on September 1. A typical young moon sighting, for most people with ordinary eyesight, comes when the moon is around 24 hours from new, or more. Thus the moon will be back in the west after sunset on September 2 or 3, sweeping near the planets Jupiter and Venus.
However, with modern techniques – telescopes, filters, photography – the moon can be seen by extremely experienced observers even at the instant of new moon. That’s the case with the image at the top of this post, acquired by experienced amateur astronomer Thierry Legault in 2013. Read more about that image here.
In other words, a waning crescent seen within seconds of new moon is within the realm of possibility if special techniques and equipment are used.
On the day of new moon itself, however, most of us can’t see the moon with the eye alone for several reasons. First, at new moon, the moon rises when the sun rises. It sets when the sun sets. It crosses the sky with the sun during the day. A new moon is too close to the sun’s glare to be visible with the eye. Plus its lighted hemisphere is facing entirely away from us. It’s only as the moon moves in orbit, as its lighted hemisphere begins to come into view from Earth, that we can see it in our sky.
A new moon is more or less between the Earth and sun. Its lighted half is turned entirely away from us. Image via memrise.com.
Composite image of a 2006 solar eclipse by Fred Espenak. Read his article on the August 21, 2017 total solar eclipse, first one visible from contiguous North America since 1979.
We can’t see the new moon from Earth, except during the stirring moments of a solar eclipse. Then the moon passes in front of the sun, and the night side of the moon can be seen in silhouette against the disk of the sun. Meanwhile, if you could travel in a spaceship to the opposite side of the moon, you’d see it shining brightly in daylight.
Once each month, the moon comes all the way around in its orbit so that it is more or less between us and the sun. If the moon always passed directly between the sun and Earth at new moon, a solar eclipse would take place every month.
But that doesn’t happen every month. Instead, in most months, the moon passes above or below the sun as seen from our earthly vantage point.
Then a day or two later, the moon reappears, in the west after sunset. Then it’s a slim waxing crescent visible only briefly after sunset – what some call a young moon.
Young moon, visible a day or so after the new moon phase. A young moon is seen in the west after sunset. It’s a waxing crescent moon. Photo by Gene Porter in Georgia. On September 2, 2016, the young moon will be near Jupiter. On September 3, it’ll be near Venus.
As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.
Four keys to understanding moon phases
Where’s the moon? Waxing crescent
Where’s the moon? First quarter
Where’s the moon? Waxing gibbous
What’s special about a full moon?
Where’s the moon? Waning gibbous
Where’s the moon? Last quarter
Where’s the moon? Waning crescent
Where’s the moon? New phase
Moon in 2016: Phases, cycles, eclipses, supermoons and more
from EarthSky http://ift.tt/19T9DUm
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