Mercury, Jupiter, and Saturn are clustering in the night sky in a rare, three-planet conjunction event. Here's how to see it on Monday.

Mercury, Jupiter, and Saturn are aligned in the night sky, appearing closer together than they've been since 2000. When three planets move into such a…

Read More Mercury, Jupiter, and Saturn are clustering in the night sky in a rare, three-planet conjunction event. Here's how to see it on Monday.