After the moon reaches its new phase on Sunday (Oct. 27), it will swing by Jupiter on Halloween.

Space.comBy Jesse Emspak 

© Starry Night software | This sky map shows where the planets will be in the Halloween night sky as seen from New York City on Oct. 31, 2019, shortly after sunset. 

The new moon occurs on Sunday (Oct. 27) at 11:36 p.m. EDT (0326 GMT on Oct. 28) — one day after the moon reaches perigee, or the closest point to Earth in its orbit, according to NASA's SkyCal site.
New moons occur when the moon is directly between the sun and Earth. About every 29.5 days the two bodies share the same celestial longitude, an alignment also called conjunction. Celestial longitude is a projection of the Earth's own longitude lines on the celestial sphere. During the new moon, if one draws a line from Polaris, the North Star due south toward the sun, that line also hits the moon. 
New moons are invisible to ground-based observers (unless the moon passes directly in front of the sun, which creates a solar eclipse) because the sunlit side of the moon faces away from Earth. No eclipses are in store for this New Moon, though. 

Visible planets

Given that the new moon occurs so close to Halloween, it's worth noting that the moon is in conjunction with Jupiter on Oct. 31. The pair will set about 2.5 hours after sunset, according to in-the-sky.org, and become visible at about 6 p.m. local time as the sky gets darker.
Two days after the new moon, on Oct. 29, the moon will be in conjunction with the planet, Venus. The conjunction itself won't be visible from New York City, as it occurs at 9:33 a.m. local time. However, the sunsets that day at 5:56 p.m., while Venus sets at 6:51 p.m., according to skywatching site In-the-sky.org. That means Venus should be visible just after sunset, as it is bright enough to show up against even a partially-lit sky. According to heavens-above.com calculations, the moon sets at 7:19 p.m. So looking west, one would see the sunset, and as the sky darkens, Venus would appear just before it dips below the horizon ahead of the day-old moon. The pair will be very hard to spot; Venus won't be more than 5 degrees above the horizon a half-hour after the sun goes down, and the moon will be no more than a slight crescent. 
Observers further south will have a slightly easier time. In San Juan, Puerto Rio, for example, Venus sets a few minutes earlier than in New York, at 7:02 p.m. local time. The sunsets at 5:53 p.m. About 30 minutes after sunset the planet is 8 degrees above the western horizon. It's still hard to spot, but easier than in New York or Boston.
The reason is that the plane of the ecliptic — the line that describes the Earth's orbit projected against the sky — is at a steeper angle to the horizon. The moon, Venus and other planets all travel close to that line in their passage across the sky against the background stars. The arrangement puts Venus a bit higher after sunset than in mid-northern latitudes. 
Going outward in the solar system, on the night of the new moon, Jupiter and Saturn will be in the southwest just after sunset. From mid-northern latitudes, they will make a diagonal line up and to the left (south). Jupiter will be in the constellation of Ophiuchus and Saturn in Sagittarius. In New York, Jupiter and Saturn will set at 8:33 p.m. and 10:13 p.m., respectively. As with observing Venus, the two planets will appear higher the further south one goes. From San Juan, the two planets set at 8:54 p.m. and 10:33 p.m. 
Fans of Mars will have to stay up late (or get up early) to see the Red Planet. In New York, it rises at 5:47 am. local time and reaches about 8 degrees of altitude by about 6:30 a.m., per heavens-above.com. Arcturus, the brightest star in Bootes (and one that shares a similar red-orange hue) will be to the left; both will be fading as the sky gets lighter. 
You can find out exactly when the planets are visible from your specific location using timeanddate.com's astronomy calculator

Stars and constellations

In late October, the "summer" constellations of the zodiac — Sagittarius, Ophiuchus, and Scorpius — are in the western half of the sky by evening. Just after sunset, at around 8 p.m. local time, the "wet region" of the sky is prominent to the south. The wet region is called that because so many of the constellations are water-themed. Looking south one sees Capricorn, Aquarius, and Pisces (as one moves the point of view to the east). Just below Pisces is Cetus, the whale. All of these constellations are relatively faint; none has a first-magnitude star. 
Closer to the southern horizon one can see Fomalhaut, the brightest star in Piscis Austrinus, the Southern Fish. Fomalhaut is a first-magnitude star that is also one of the sun's closest neighbors, "only" 25 light-years away. 
To the north from Aquarius, you can see the constellations of Pegasus and Andromeda, marked by an asterism called the Great Square. One corner of the square is Andromeda's head, while the other three marks the wing of Pegasus, the legendary flying horse ridden by Perseus to save Andromeda from a sea monster. 
From Andromeda's head, one can trace two lines of stars and find the Andromeda Galaxy, which can be spotted from a dark-sky site with the naked eye. 
This article was originally published by Space.com.
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