Mercury, Venus, Mars, Jupiter, Saturn, Neptune and Uranus could be visible, but not all can be seen by the naked eye.

According to NASA, multi-planet lineups are visible "every few years," but a seven-planet alignment is particularly uncommon, as each planet's orbit varies, with some moving more quickly and Mercury, in particular, being visible during its 88-day orbit for only "a couple of weeks at a time" each year.

For example, you’ll need binoculars or a small telescope to see Uranus and Neptune—so, while the seven planets will be there, spotting them all will require specific equipment. Several of them will only appear low on the western horizon around twilight, but three will be bright and high in the sky after sunset.