Feeling blue? Seek out Neptune tonight

Though often difficult to track down, a view of Neptune is always a rewarding sight.
By | Published: January 7, 2019 | Last updated on May 18, 2023

neptune
Neptune never looked better than when the Voyager 2 spacecraft zoomed by it in 1989 and took this image. You can pick up traces of the planet’s color even through a small telescope.
NASA/JPL-Caltech

Although relatively nearby Venus made a brilliant appearance before dawn yesterday, tonight, a more distant planetary neighbor will strut its stuff: Neptune.

When it comes to brightness, Neptune is on the other end of the planetary spectrum from Venus. Because Neptune is not visible with the naked eye, even from a dark sky site, it takes the right equipment and some searching to find it.

As the sky fully darkens tonight, you can use binoculars and look toward the southwest to locate the star 81 Aquarii, which glows just below naked-eye visibility at magnitude 6.2.

After locating 81 Aquarii, look 0.4° to the east to find Neptune.

At magnitude 7.9, the eighth planet in our solar system glows nearly two magnitudes fainter than the star. Viewed through a telescope, Neptune’s vivid blue color will reveal it.

For more quick and easy observing tips, make sure to check out The sky this week for January 4 to 13.