As dusk fades to dark on Sunday, 17 April, observers in the British Isles should look up to the southern sky to see the 10-day-old waxing gibbous Moon and Jupiter just four degrees apart, within the same binocular field of view. Jupiter’s largest moon, Ganymede, and second Galilean moon, Europa, provide some events for telescope owners to view at higher magnifications.
The impact of a small comet or asteroid on Jupiter observed by European amateur astronomers on 17 March has heightened interest in the solar system’s largest planet. While such an event is uncommon, Jupiter and its family of four bright Galilean moons provide a wealth of other interesting phenomena to view with small telescopes during April.
As darkness falls, observers in Western Europe and the British Isles fortunate to have clear skies can view a naked-eye conjunction between largest planet Jupiter and the Moon. For telescope owners, Jupiter’s Great Red Spot will be on show, while Galilean moons Io and Europa partake in a close orbital dance.
If you haven’t done so already, now is the time to ensure that your telescope is clean and collimated (aligned) to deliver the sharpest images of planet Jupiter at its best. We tell you the optimal UK times to view the largest planet’s Great Red Spot and multiple shadow transits from its Galilean moons.
In the early evening of Tuesday, 23 February, the rising waning gibbous Moon — one day after full Moon — lies just 3½ degrees from magnitude -2.5 planet Jupiter low in the eastern sky. Jupiter is closest to Earth on Tuesday, 8 March, so now is the time to get acquainted with the solar system’s largest planet.
Observers in the British Isles and western Europe with a clear sky low to the east around 10pm local time on Wednesday, 27 January can see the rising 18-day-old waning gibbous Moon in a close conjunction with Jupiter, the solar system’s largest planet. Jupiter draws steadily closer to Earth and grows in apparent size over the coming weeks.
In the dawn twilight of Friday, 4 December observers in the British Isles and Western Europe can see the 23-day-old waning crescent Moon just 2.5 degrees (half a 10×50 binocular field of view) below largest planet Jupiter in the constellation Leo high in the southern sky. And if you have a telescope, Jupiter’s largest moon plays hide and seek.
The numerous whirlwinds covering Jupiter are caused by upward gas flows originating deep within the giant planet. This is the conclusion reached by scientists at the University of Alberta (Canada) and the Max Planck Institute for Solar Research (MPS) in Germany after extensive computer simulations. Their models also explain why the Jovian whirlwinds’ direction of rotation is opposite to storms on Earth.
Scientists using the NASA/ESA Hubble Space Telescope have produced new maps of Jupiter that show the continuing changes in its famous Great Red Spot. The images also reveal a rare wave structure in the planet’s atmosphere that has not been seen for decades. This is the first in a series of annual portraits of the solar system’s outer planets which will help researchers study how they change over time.