Jupiter ready for its close-up this week

Astronomers from Alberta will be looking up at the heavens this week, as they try to capture the best view of Jupiter since 1951.

The planet Jupiter was a mere 591 million kilometres away from Earth on Sept. 26 — the closest it has been to this planet in 70 years.

Frank Florian, senior manager of planetarium and space sciences at the Telus World of Science Edmonton, said he and other area astronomers will be taking many pictures of Jupiter this month to take advantage of this event. Jupiter hasn’t been this close to Earth since Oct. 2, 1951, and won’t be this close again until Oct. 7, 2129.

“It’s the largest planet in our solar system, and right now it appears very, very brightly in our evening sky,” Florian said.

Murray Paulson, an astronomer from St. Albert, explained that Earth and Jupiter have elliptical orbits. They are closer to the Sun at certain points than others. When they are in opposition, when Earth is between Jupiter or the Sun, Earth and Jupiter are closest to one another. These oppositions occur about once every 13 months because Earth orbits the Sun 12x faster than Jupiter. The distance between the planets varies depending on their elliptical orbits.

Earth is headed out away from the Sun right now while Jupiter is heading towards it, Paulson said. On Sept. 26, the two planets were also in opposition, making them super close and Jupiter appear about 15 per cent bigger in the night sky.

This is not a difference most people would notice unless they have been taking regular pictures of Jupiter, Florian said. Still, this is an excellent time to take pictures of Jupiter, as it is high in the sky over Edmonton, which means less atmosphere to shoot through and clearer pictures.

NASA reports that Jupiter is the largest planet in the solar system. It has twice the mass as all the other planets. Jupiter would be about the same size as Earth if it were a grape.

Jupiter is a “sun wannabee” in that it could have become a star if it had more mass, Florian said. Instead, it’s a gas giant composed of swirling masses of hydrogen, helium, ammonia, water, and some organic compounds. It has the second-strongest magnetic field in the solar system next to the Sun’s, and has aurorae at its poles.

Paulson stated that Jupiter is well-known for its many surface thunderstorms. You can see them through a telescope. The Great Red Spot is the most well-known, and it is twice as large as Earth. It has been raging for more than a century. The Great Red Spot has also visibly changed shape and colour over the years — Paulson said it is now smaller and more salmon pink than it was a few decades ago.

There are approximately 75 moons orbiting Jupiter, with the largest four visible through binoculars. Florian stated that these moons can be seen casting shadows over Jupiter if you look closely.

Paulson stated that researchers have seen sprays of water projected from Europa, one of the moons. This suggests that Europa may have liquid water beneath its surface.

“Anywhere there’s water, there also could be life.”

Paulson said Jupiter will be the brightest star in the eastern sky over the Edmonton region this week, and will pass through the constellation Pisces.

Florian said residents will continue to have an excellent view of Jupiter for about a week after Sept. 26.