Joe Bauman: First time to watch Jupiter and news on the planet

Editor's Note: This has already been published on the website of the author.

Jupiter, the king of the planets of our solar system, has been known as a special light in the sky probably since the first humans stopped scratching long enough to look up. She and the other formerly known planets are distinguished from stars by relative brightness (most), their propensity to wander and their refusal to sparkle. The ancient Greeks called it Zeus, after the name of their supposed gods, and the Romans continued with their own version of the name, which we use today.

As Bruce McClure of EarthSky.org points out, we are in the "month of opposition" with Jupiter, which means that it is in the most advantageous position for viewing. The earth and the large striped object are on the same side of the sun, which makes Jupiter visible all night, rising at sunset and setting at dawn. In between, he crosses the sky from east to west. Jupiter is also relatively close, about 400 million kilometers.

Recently my wife, Cory, and I watched with binoculars from our home in Salt Lake City. It was harder than it looks. The long focal length bounces the view, because the arms do not make good tripods. Even when I lay on the grass with an elbow on the floor, the view was not stable. Worse, the light pollution attenuated the contrast and I could not see the four Galilean satellites supposed to be visible. It was always exciting, though.

New exciting discoveries arrived just in time for the month of opposition:

• On May 21, the Royal Astronomical Society of London announced that the first permanent intruder known in our solar system from another star is in orbit around Jupiter. (The only other visitor of this type to be identified was the strange cigar-shaped object, called 'Oumuamua, seen last year coming out of our system.) The new object is an asteroid which appears as a point on the photographs; he received the non-romantic name (514107) 2015 BZ509.

Scientists believe that it came from a distant star because it is in orbit in the opposite direction of all other satellites of Jupiter. The company quotes Fathi Namouni, the main author of the new report, saying, "How did the asteroid get to move in this way while sharing the orbit of Jupiter has up to the point of time. has now been a mystery. " If BZ509 was formed in our solar system, it would have turned in the same direction as almost everything else.

The sun has emerged with other stars in a group, "where each star had its own system of planets and asteroids," quotes fellow researcher Helena Morais. "The proximity of the stars, aided by the gravitational forces of the planets, helps these systems to attract, remove, and capture asteroids from each other."

Later, Sol and his siblings split up.

• On May 14, the journal Nature Astronomy announced that a sophisticated analysis of magnetometer and plasma wave data acquired in 1997 appears to verify that water plumes escape in the future. Space since the jovian moon Europa. The plumes were suspected based on the Hubble Space Telescope photos, but the details were at the limit of visibility and therefore the assumption was not proven. The newly analyzed data was collected during close passages over Europa by the Galileo spacecraft.

Lead author of the study, Xianzhe Jia of the University of Michigan, Ann Arbor, was appointed investigator for two instruments to be launched to Europa in the 2020s aboard the Europa Clipper spacecraft , according to NASA. Europa Clipper should be able to capture samples from the Europa neighborhood and analyze them.

Robert Pappalardo, a researcher at the Jet Propulsion Laboratory in Pasadena, quoted by the JPL, said: "If plumes exist and we can directly taste what comes from inside Europa, we can more easily determine if Europa has the ingredients. for life. … it's the big picture. "

From a smaller point of view, Jupiter is my favorite planet for telescopic viewing because it is dynamic. Nineplanets.org points out that if the Earth was the size of a grape, Jupiter would be a big grapefruit. Yet, despite its size, it does a full rotation in about 10 hours. One can notice a movement by looking through a telescope for several minutes because the features appear on one side and move towards the other.

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Among its dozens, the four largest moons of Jupiter – going to the outside, Io, Europa, Ganymede and Callisto – were discovered by Galileo in 1610 using his primitive telescope. On clear, dark nights, some or all may be visible using small telescopes or binoculars. Their orbits continually change their orientation, often causing eclipses when a moon shadow falls on the planet. The orbits of these moons are precise and well understood; For centuries, tables of their positions have been used to determine longitude on Earth.