Earth is about to pass between the sun and Jupiter, placing Jupiter opposite the sun in our sky on April 7, 2017, at 22 Universal Time (5 p.m. Central Time). Astronomers call this event an opposition of Jupiter. Therefore, Jupiter now rises in the east around sunset, climbs highest in the sky at midnight and sets in the west around sunrise. It shines more brightly than any star in the evening sky, and is the second-brightest planet, after Venus. But Venus only shines for a short while before sunrise at present while Jupiter stays out all night long.
Jupiter blazes away in front of the constellation Virgo the Mainden. The close 1st-magnitude star to Jupiter is Spica, the brightest star in Virgo. However, dazzling Jupiter outshines this star by over 20 times.
Jupiter comes to opposition about every 13 months. In other words, that’s how long Earth takes to travel once around the sun relative to Jupiter. For instance, last year – in 2016 – Jupiter’s opposition date was March 8. Next year – in 2018 – it’ll be May 9.
Jupiter’s closest approach to Earth for the year always falls on or near this planet’s opposition date. In 2017, Jupiter comes closest to Earth one day after its opposition date, on April 8, coming to within 414 million miles (666 million kilometers) of Earth.
And, because it’s opposite the sun around now, you can see Jupiter at any time of night. For example – as the chart at the top of this post shows – you can see it in the east at nightfall and early evening. Around midnight, when the sun is below your feet, Jupiter appears high overhead. At dawn tomorrow, you’ll see Jupiter low in your western sky.
Jupiter is sometimes called a failed star. You would need at least 80 Jupiters – rolled into a ball – to be hot enough inside for thermonuclear reactions to ignite. In other words, Jupiter is not massive enough to shine as stars do.
But Jupiter is the largest and most massive planet in our solar system. So when the sun goes down on this April night, you might — if you’re fanciful enough — imagine bright Jupiter as a tiny sun all night long.
Bottom line: Be sure to look for Jupiter on the nights of April 7 and April 8 as this world reaches opposition and its closest point to Earth for this year!