The new moon occurs March 24, at 5:28 a.m. EDT (0928 GMT), a day after Mercury reaches its highest point in the morning sky and on the same day Venus reaches its maximum altitude in the evening, according to NASA's SkyCal site.
A new moon occurs when the moon is between the Earth and sun, and the two bodies share the same celestial longitude. (Celestial longitude is a projection of the Earth's own longitude lines on the celestial sphere). Such an alignment is also called a conjunction. Because the illuminated side of the moon is facing away from us, new moons are generally not visible from Earth unless the moon passes in front of the sun, as happens during eclipses.
On March 23 at 9:59 p.m. EDT (0059 GMT), Mercury will reach greatest western elongation, reaching the maximum angular distance from the sun from the point of view of Earth, according to SkyCal. That puts it as high as it gets in the predawn sky. Even then, for observers in mid-northern latitudes it's a challenge to observe, as from New York City it won't get more than about 10 degrees above the horizon at sunrise on March 22, and about 9 degrees above the horizon on March 24, per sky watching site In-The-Sky.org. (The orbit of Mercury is inclined to the horizon and the plane of the Earth's orbit, so the day it gets its maximal altitude differs slightly from the date of greatest elongation).
On March 23, Mercury will be in the constellation Aquarius, rising at 5:58 a.m. local time in New York, with the sun following at 6:54 a.m. By 6:30 a.m., the sun will be 6 degrees below the horizon and the sky is getting lighter. However, Mercury is just bright enough to be visible and will be about 6 degrees above the horizon, according to Heavens-Above.com calculations.
Prospects for seeing Mercury get better as one moves south. From Miami, the innermost planet will be 15 degrees above the horizon at sunrise on March 24, which is at 7:21 a.m. local time. Mercury rises at 6:04 a.m. local time in Miami. By the time civil twilight starts on the morning of March 23, at 6:58 a.m. local time, the planet will be 11 degrees above the eastern horizon.
Even better views will be in the Southern Hemisphere, where the orbit of Mercury (once again, from the point of view of Earth) makes a steeper angle with the horizon. From Buenos Aires and other cities in the mid-southern latitudes Mercury will be a full 20 degrees above the horizon on March 23 at about 6:30 a.m. local time; sunrise is at 6:59 a.m. local time.
Venus, meanwhile, will grace the evening skies and reach its greatest eastern elongation at 5:59 p.m. EDT (2159 GMT) on March 24, the very night of the new moon. The planet doesn't set until 11:10 p.m., so at sunset at 7:13 p.m. it is a full 44 degrees above the western horizon. Venus is bright enough that it is often one of the very first celestial objects people notice; it shines at magnitude -4.4, about 15 times as bright as the brightest star in the Northern Hemisphere sky, Sirius.
For Southern Hemisphere observers, viewing conditions for Venus are the inverse of Mercury's — in Buenos Aires, the planet will be no more than 19 degrees above the horizon on the evening of March 24 at sunset, which is at 6:58 p.m. local time. That's still quite high enough to be easily visible as twilight gets underway.
In New York City, Jupiter, Mars, and Saturn will rise respectively at 3:43 a.m., 3:56 a.m., and 4:05 a.m. local time on March 25. By 6 a.m. they are at altitudes between 17 and 19 degrees, making a photogenic line with Saturn on the left, Mars in the middle and Jupiter on the right.
On the night of the new moon, observers in mid-northern latitudes will still see the winter sky constellations giving way to those of spring. Orion, Taurus, Gemini and Canis Major are already high in the south by 8 p.m. local time.
In the east, Leo is well above the horizon and Virgo is rising. By midnight, Leo is near the meridian in the south, while facing north one can see the Big Dipper and Ursa Major, the "big bear," at their highest points.
Following the handle of the dipper allows one to "arc" to Arcturus, the brightest star in Boötes, the herdsman, in the northeast, while just above the horizon Vega, one of the stars of the Summer Triangle, which rises just after 11 p.m., presages the arrival of summer stars.
For the mid-southern latitudes, by about 8 p.m. on the evening of the new moon Canopus, one of the brightest stars in the sky, will be near the meridian in the south, and to its left the Southern Cross and Centaurus will be in the south-southeast. Centaurus contains Alpha Centauri, the solar system's nearest stellar neighbor and the site of countless science fiction stories. Just to the south-southwest and closer to the horizon one can see the star Achernar, the end of the constellation Eridanus, the river, and if one follows its winding path it will lead to an "upside down" Orion constellation, which will be moving towards the northwestern horizon.
Editor's Note: If you snap an amazing night sky picture and would like to share it with Space.com's readers, send your photos, comments, and your name and location to email@example.com.
All About Space magazine takes you on an awe-inspiring journey through our solar system and beyond, from the amazing technology and spacecraft that enables humanity to venture into orbit, to the complexities of space science.View Deal