Skywatchers gathered for an exciting astronomical event starting on Wednesday night, when the planets in our solar system became visible in the sky at the same time, most of them to the naked eye.
Experts say such an event only occurs every few years. On Wednesday, planets Mercury, Venus, Mars, Jupiter, and Saturn were visible simultaneously to the naked eye, starting from the southwestern horizon, while Uranus and Neptune, the two outermost planets, could be observed with binoculars or a telescope.
Mercury, Venus, Mars, Jupiter, and Saturn will be visible on Thursday too, though Mercury, the smallest planet, is likely to be the most difficult to see unless in the clearest of conditions.
Uranus can be seen between Mars and Jupiter, while Neptune can be spotted between Saturn and Jupiter.
According to the Guardian, all eight planets “appeared only 1.5 degrees apart on Wednesday night and were set to reach conjunction – their closest point – on Thursday at 2100 GMT.”
Vahé Peroomian, a professor of astronomy and physics at the University of Southern California told CBS News that because Uranus rotates around the Sun twice as fast as Neptune, the two planets will soon go back to being far apart from each other.
Therefore “it won’t be possible to see both planets in the night sky at the same time for several decades,” Peroomian said.
The Rome-based Virtual Telescope Project, which offers a set of robotic telescopes remotely accessible online, said in a preview of the event that “at the end of the year, the sky offers us the opportunity to see all the planets of our solar system at the very same time.”
Gianluca Masi, an astronomer with the Virtual Telescope Project, told Newsweek last week: “These nights, we can see all the planets of our solar system at a glance, soon after sunset. It happens from time to time, but it is always a spectacular sight.”
Masi said that for Mercury fans, “the much brighter Venus” will help locate the planet closest to Earth, “the latter being within 2 degrees or so of the former.
According to CBS News, the “planet parade” tends to happen every couple of years.
However, the last time planets were visible simultaneously was June. In that event, planets could be seen in the same order in which they orbit the Sun — Mercury, Venus, Mars, Jupiter and Saturn.