Return to Newsletter Index

Planet Watch 2016

by Perry Pezzolanella

Night time on the World of Life will be exciting throughout 2016. Venus, Mars, Jupiter, Saturn will keep observers busy every night throughout the year with all four visible at once during summer! The night sky is always capable of a few surprises. Perhaps there will be unusually active meteor showers or an unexpected bright comet or a beautiful aurora. There are always beautiful lunar and planetary conjunctions and countless asteroids, satellites, Iridium flares, and the reliable International Space Station.

The main event of 2016 will be the transit of Mercury across the Sun on May 9. The entire transit will be visible locally if the weather permits. The transit begins at 7:12 A.M. and ends at 2:42 P.M., lasting a solid 7½ hours. There are no lunar or solar eclipses during 2016 but a partial eclipse of the Sun will be visible next year on August 21 with the Sun high up and 70% eclipsed. It is expected that several MVAS members will be elsewhere in the U.S. observing totality, hopefully snapping a 17-year unlucky streak of clouded-out solar eclipses for most of us. The last successful solar eclipse locally was on Christmas Day 2000 with the Sun 60% eclipsed.

Jupiter will dominate the evening sky during the opening months of the year to be joined by Mars and Saturn by April, and all three will vie for attention well into summer. Mercury will try and steal the show fleetingly during April, but Venus will certainly gain a stronghold in the evening skies as summer fades into autumn. Jupiter will depart into the western twilight during August with Saturn slowly fading into the twilight towards Halloween. Mars will linger with Venus into the early months of 2017 but will grow small and dimmer. Uranus and Neptune will be at their best from September through the end of the year and should not be overlooked even if they are not brilliant planets. Here is the breakdown for each planet in the evening sky during 2016:

Mercury: The World of Elusiveness is always a challenge to find because it is always so low to the horizon and in bright twilight, but it is easiest to see in the evening from April 4-28, being highest above the horizon on April 18. Mercury grows steadily through this period from 6 to 10 arcseconds across as it approaches Earth, and its magnitude will dim from -1 to +2. It will go through phases like a tiny, coppery version of the waning Moon, from nearly full to a thin crescent.

Venus: The World of Brilliance will return to the evening sky in August. It will be rather low until December when it finally climbs higher and will begin to dominate the evenings into March 2017 shining as bright as magnitude -4.9 by next February. It will grow from a nearly full disc about 10 arcseconds across in August to a huge, thin crescent nearly one arcminute across by next March. Venus will literally sparkle in the frigid winter evening skies and will be capable of casting shadows in the snow.

Mars: The World of Dreams will be at its best since 2005 when it reaches opposition on May 22 but due to its highly elliptical orbit it will be closest to Earth on May 30 when it will be a respectable 18.6 arcseconds across and shine at magnitude -2.1 in Scorpius. It will be possible to see one or both of the polar ice caps and dusky surface features. Mars will steadily shrink to less than 8 arcseconds across and grow dimmer than magnitude 0 by autumn as it slowly sinks in the west into early 2017.

Jupiter: The World of Huge is transitioning into a spring planet with opposition occurring on March 8 near the Virgo-Leo border, having an angular diameter of 44.3 arcseconds across and shining at magnitude -2.5. Jupiter begins the year rising in the east during the evening, making for an excellent opportunity to follow it through one full rotation during the long winter nights as it rotates in less than ten hours while winter nights last more than 12 hours. Jupiter is consistently huge through the telescope making it rewarding to observe and photograph. The cloud belts and both polar hoods can be scrutinized in fine detail and the challenging Great Red Spot can sometimes be seen. It might be possible to see the tiny discs of the larger moons, Callisto and Ganymede, and watch all four moons transit Jupiter and follow their shadows across the giant planet. Jupiter will eventually become lost in the evening twilight by August as it fades to magnitude -2.0 and shrink to 33 arcseconds across. Jupiter will not rise before midnight until early 2017.

Saturn: The World of Beauty is at its best with the rings as wide open as possible and will once again be the highlight of all star parties during the mild spring nights and balmy summer evenings. The rings will provide plenty of detail with the Cassini Gap being the obvious feature. Saturn is at opposition in Ophiuchus on June 3 when it will be 18.4 arcseconds across and shine at magnitude 0.0. No other planet can rival the beauty of Saturn and there is a wealth of detail to see. Saturn dominates the warmer part of the year, which will allow an excellent opportunity to study its belts and spots, and to look for the Cassini Division in the rings. The largest moon, Titan, is usually visible, shining about 8th magnitude. Saturn will slowly fade to magnitude +0.6 and shrink to around 16 arcseconds across in November when it becomes lost in the evening twilight.

Uranus: The World of Jokes will be at opposition on October 15 in Pisces. Uranus will be 3.7 arcseconds across and shine at magnitude +5.7 not far to the east of the bright star Zeta Piscum making it easy to locate again this year. Uranus rises before midnight by August and gradually fades into the evening twilight by March 2017.

Neptune: The World of Change is at opposition on September 2 in Aquarius below the Water Jar and close to bright Lambda Aquarii making it unusually easy to locate and follow. Neptune will be 2.4 arcseconds across and shine at magnitude +7.8. Neptune will rise before midnight by July and disappear into the evening twilight during February 2017. A finder chart for Uranus and Neptune will appear in the August issue of Telescopic Topics.

Pluto: The World of Awe is no longer a mystery as we now know what Pluto looks like thanks to the historic flyby of New Horizons last July 14. Pluto is at opposition on July 7 still in the Teaspoon asterism of Sagittarius among thousands of stars and will shine like a faint spark at magnitude +14.1. It will be only 0.1 arcseconds across making it a challenge to find. Pluto is slowly exiting the heart of the Milky Way making the task of confirming it perhaps a touch easier. We now will forever look at the dim speck of Pluto and picture it with its giant icy heart.