This week, the Earth will be able to see a rare alignment of five planets. 

Since December 2004, Mercury, Venus, Mars, Jupiter, and Saturn are aligning in this sequence for the first time. Friday, June 24 will be the best day to see the event.

According to Sky & Telescope, the conjunction of three planets is common, but a conjunction of five planets is unusual. The planets are aligning in their natural sequence from the Sun, which is equally exceptional, according to the American Astronomical Society’s scientific journal.

The five so-called “naked-eye” planets were seen starting on June 3 and 4, and the line-up was visible with binoculars for approximately a half-hour before Mercury disappeared into the sun’s brightness.

But on June 24, visibility will be at its peak. Even though the distance between Mercury and Saturn grows, it’s growing easier to identify Mercury, thus it’s getting easier to view all five planets, according to Sky & Telescope observing editor Diana Hannikainen.

The 24th’s morning sky, according to Hannikainen, “will be a sight to see” since the declining crescent moon will join the procession between Venus and Mars.

The planets ought to be visible in the following days. According to Sky & Telescope, the optimal time to see the lineup on June 24 is 45 minutes before dawn. On the eastern horizon, it should be visible.

NASA reports that four of the planets visible to the naked eye have been aligning in over the last several months. However, during the next months, Saturn, Mars, Jupiter, and Venus will scatter. Venus and Saturn will no longer be visible to the majority of viewers by September.

Reference(s): SkyandTelescope