30 April 2017

Now is the time to view Jupiter

Hubble Image April 2017
Jupiter is the brilliant 'star' that is currently dominating the evening sky, outshining all other celestial objects except the Moon. The largest planet in the Solar System, Jupiter is on the Top 10 viewing list for every backyard astronomer because it is easy to find and offers such richness when viewed with magnification, and of course it is dazzling whether viewed from the darkness of a country setting or the bright lights of an urban setting. And having just passed opposition in early April, Jupiter is well positioned for viewing shortly after sunset and is above the horizon nearly the entire night; being just past opposition also means that Jupiter presents the greatest surface area for viewing. A casual glance toward the south-east in the evening is all you need to find Jupiter.

Intricate Details on Jupiter
The image on the right from Sky & Telescope shows the intricate details visible on the surface of the planet. Any telescope of good quality will reveal the major bands on Jupiter's Northern and Southern Hemispheres, and a CCD will capture the Great Red Spot and some of the patterns in the clouds. The four largest moons of Jupiter add a dynamic and ever-changing view to the planet, with regular transits and eclipses adding live drama to an evening focused on just one celestial object. Sky & Telescope has an excellent article that highlights many of the things you can see on Jupiter - it's worth a short read. It also includes links to detailed timings of the transit of the Great Red Spot and the Jovian moon transits and eclipses.

NASA recently pointed the Hubble Space Telescope at Jupiter as part of its ongoing planetary exploration looking at not only the planet but its moons, each of which has an interesting geological history and aids in understanding the formation of the Solar System. This short video on HubbleSite provides further details on their work.

Jupiter is presently in the constellation Virgo just above the bright star Spica and slowly moving retrograde toward Porrima in the coming two months. Given the relative orbital speeds of the Earth and Jupiter, we see Jupiter in a different sign of the Zodiac each opposition; approximately every 12 months Jupiter has moved to the next sign. That means in a year Jupiter will be found in the constellation Libra, and a year later in Scorpius.

Images courtesy NASA and Sky & Telescope.