The movement of the Earth, faster by being in an inner orbit, will cause that during the night of May 8 to 9 the planet Jupiter is located almost exactly opposite the sun as our planet passes between the two largest stars of the solar system. This is what astronomers call the opposition, and around that moment is when the outer planet, in this case, Jupiter, is in a better condition for its observation.
This is because at the moment of opposition is when the three bodies, Jupiter, the Earth and the Sun, form a straight line with the planet Earth in the middle, on the same side of the Sun as Jupiter. Around the date of an opposition is when the planet Jupiter will be at the point closest to Earth and you can better see its details through the telescope.
In addition, when Jupiter is found in the opposite direction to the Sun, the planet comes out on the eastern horizon just at the time of sunset and disappears in the west at dawn, and is visible throughout the night. It is easy to locate it near the stars Spica and Arcturus, on the south-east horizon in the early hours of the night. In addition, the planet Jupiter will be these nights the brightest point of the night sky, only surpassed by the planet Venus, the “morning star”, which is seen these days only just after sunset on the western horizon.
The planet Jupiter will be these nights the brightest point of the night sky, only surpassed by the planet Venus, the “morning star”.
The oppositions of Jupiter happen approximately every 13 months, and the next one will be on June 10, 2019. Throughout this month of May, we have a magnificent opportunity to look at this giant of the Solar System and its four main moons, which were studied for the first time once by Galileo Galilei more than four centuries ago. With a small telescope, we should already be able to observe the four Galilean satellites and even some details on the surface of Jupiter. About 3 hours later than Jupiter, Saturn also appears on the south-east horizon, which will reach its own opposition on June 27.
Why will it be closer?
The moment of the opposition of an outer planet, such as Mars or Jupiter, occurs when this planet is aligned with the Sun and the Earth, and our planet is left in the middle. We might think that this must exactly coincide with the closest approach between Earth and Jupiter. However, in the case of Jupiter’s opposition this May, the giant planet will be closer to Earth about a day and a half after the opposition, during the afternoon of the 10th. In that instant, we can see the planet giant about 658 million km from us. The shape of the orbit of the planets, which is slightly elliptical and not circular, is what makes the outer planet closer to something before or after the opposition. Actually,
It is a magnificent opportunity to look at this giant of the Solar System and its four main moons, which were first studied by Galileo Galilei just over four centuries ago.