Astronomy Club of Asheville July 2016 Sky Events

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1 July 2016 Sky Events The Planets this Month - page 2 Planet Highlights - page 7 Moon Phases - page 10 July 4 th - Earth Reaches Aphelion - page 11 July 28/29 - Delta Aquarid Meteors - page 13

2 July 2016 Sky Events the Planets July 2016 provides 3 planets that will brighten the early evening skies. Jupiter will dominate the west while Mars and Saturn will reign in the south. Against the background of the constellation Leo, Jupiter is best viewed early in the evening this month, before it sets in the west. Mars, although rapidly fading, remains in great viewing position this month high in the sky for most of the night in the constellation Libra. The planet Saturn can be found within the boundaries of the constellation Ophiuchus, the Serpent Holder, all month, and it s a great time to observe it with a telescope. Saturn s rings are currently tilted a wide 26 toward us (near their maximum angle of 27 ); so the rings will look spectacular in the telescope eyepiece. You will be looking at Saturn s rings from above on their northern face; not until the year 2025 will you be able to catch a glimpse of the rings from the planet s southern face!

3 July 2016 Sky Events the Planets The Moon Joins the Planet Jupiter On the evenings of July 7-9, the waxing crescent Moon joins the bright planet Jupiter in the constellation Leo. The two solar system objects will appear closest on the night of July 8 th when they are separated by about 5 and located about 28 above the horizon. Although these 2 celestial objects appear close in our 2-dimensional view, Jupiter is some 548 million miles behind the Moon! Image courtesy of Sky & Telescope

4 July 2016 Sky Events the Planets Conjunction of the Moon with Mars & Saturn On the evenings of July 14-16, the waxing gibbous Moon appears to glide past the planets Mars and Saturn. The two planets easily outshine the red giant star Antares in the constellation Scorpius. Image courtesy of Sky & Telescope

5 July 2016 Sky Events the Planets On July 6 th Mercury reaches superior conjunction on the other side of the Sun from Earth. Venus and Mercury will be lost in the Sun s glare and not easily observable until the last week of the July. By then both planets will be orbiting toward Earth from behind the Sun. Looking very low into the west at dusk, you should be able to spot Venus and Mercury during the last week of July. Using binoculars will definitely help your effort to locate them Uranus and Neptune can be found in the pre-dawn skies this month in the constellations Pisces and Aquarius respectively. You will need binoculars or a telescope to locate and observe these two distant planets.

6 July 2016 Sky Events the Planets Locate all 5 Naked-Eye Planets Simultaneously Scorpius Both the planets Saturn and Mars, located on the border of the constellation Scorpius, outshine the bright red giant star Antares. Looking high in the South You may see all 5 nakedeye planets at the same time in the early evening during the last week of July. This is the scene for Friday night, July 29 th, about 9:10 p.m. EDT. All three planets, Jupiter, Mercury & Venus, easily outshine the bright star Regulus in the constellation Leo. Due to their low position at dusk, Regulus, Mercury and Venus will be challenging to spot. A pair of binoculars will help! Leo Looking low to the Western horizon

7 July 2016 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 1 of 3 Mercury 1.2 AUs Venus 1.7 AUs Gemini, Cancer & Leo Gemini, Cancer & Leo Reaches superior conjunction on July 6 th Not visible until the last week of the month Mars 0.6 AUs Libra Shining brightly in the night sky most of the night

8 July 2016 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 2 of 3 Jupiter 5.9 AUs Leo View it early before it sets this month Saturn 9.3 AUs Ophiuchus Great month to view it with a telescope Uranus 20 AUs Pisces Find it in the pre-dawn sky this month

9 July 2016 Planet Highlights Planet Distance from Earth Constellation(s) Diameter in arc seconds Magnitude Comments Page 3 of 3 Neptune 29 AUs Aquarius Find it in the pre-dawn sky this month

10 The Moon July 2016 New Moon 4 th 7:01 a.m. First Quarter 11 th 8:52 p.m. Full Moon** 19 th 6:57 p.m. Last Quarter 26 th 7:00 p.m. ** The Thunder Moon Unless otherwise indicated, all times are EDT

11 July 4 th July 2016 Sky Events - Earth Reaches Aphelion Earth reaches aphelion the farthest position from the Sun in its annual elliptical orbit. Distances in miles: Aphelion 94.5 million Perihelion 91.5 million Average 93 million or 1 astronomical unit (AU) ~ the Earth-Sun distance < Sun Earth > There is a 3.3% change in the distance from aphelion to perihelion. Not to scale

12 July 4 th July 2016 Sky Events - Earth Reaches Aphelion On July 4 th this year you may notice that you are orbiting on planet Earth slower than usual! Here s why: Kepler s 2 nd Law of Planetary Motion states that an imaginary line joining a planet and the Sun sweeps out an equal area of space in equal amounts of time. Perihelion Aphelion Not to scale As determined by Kepler s 2 nd Law of Planetary Motion, the speed of a planet along its elliptical orbit is fastest when it is closest to the Sun (perihelion) and slowest when it is farthest from the Sun (aphelion).

13 July 2016 Sky Events Delta Aquarid Meteor Shower The Delta Aquarid Meteor Shower peaks in late July, around July 28 and 29, with estimates of 10 meteors per hour predicted. These meteors tend to be faint. The meteors should be visible for a few weeks on either side of the estimated peak dates, and they appear to radiate from the direction of the Delta star ( Skat ) in the constellation Aquarius hence their name. Look for these meteors between midnight and dawn. A waning crescent Moon will be visible after midnight and before dawn in late July, but its moonlight, although not ideal, should not interfere much with observing the meteor shower. An unobstructed view of the sky at a dark location will increase your observing success.

14 July 2016 Sky Events Delta Aquarid Meteor Shower The view about 1:00 a.m. local time on July 28 th & 29 th. The Delta Aquarid meteors will appear to radiate from this area of the sky.

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