That's because it's about 31,000 miles more distant than 2015's other full moons.

Sergey Nivens/Shutterstock.com

Tonight is the full "Worm Moon," but it might not be that impressive. Heck, you probably shouldn't even bother glancing up. Due to an alignment of phase and distance, the lunar orb could look weirdly shrunken, like a gray, moldy apple forgotten on the counter.

That's because the moon is baring it all at its farthest point from earth—about 31,000 miles more distant than 2015's other full moons. The rocky satellite's orbit is elliptical; when it's at perigee closest to the planet, it can look bigger, and when it wanders to its most-distant apogee it can seem smaller. When it reaches its full phase at apogee some folks call it a "micromoon." That pop-culture term distinguishes it from its opposite partner, the "supermoon," an astrological bugbear supposedly responsible for earthquakes, tsunamis, and volcanic eruptions. (That's rubbish, of course.)

The upshot is that the full moon will be less bright and fat, as depicted in this mock-up from Alan Dyer at Amazing Sky:

NASA

Don't you just want to pat the left one condescendingly on the head? But though the differences look stark here, up in the celestial dome it might be more subtle. Explains Tony Phillips at Spaceweather:

Can you tell the difference? Some people say "yes," others "no." There are no rulers floating in the sky to measure lunar diameters. Without a reference, it can be challenging to distinguish an apogee Moon from a perigee Moon. Decide for yourself. Go outside after sunset on March 5th, look east, and enjoy the mini-moonlight.

About the Author

Most Popular

  1. photo: a commuter looks at a small map of the London Tube in 2009
    Maps

    Help! The London Tube Map Is Out of Control.

    It’s never been easy to design a map of the city’s underground transit network. But soon, critics say, legibility concerns will demand a new look.

  2. Perspective

    Why Car-Free Streets Will Soon Be the Norm

    In cities like New York, Paris, Rotterdam, and soon San Francisco, car-free streets are emerging amid a growing movement.

  3. Design

    New York City Will Require Bird-Friendly Glass on Buildings

    Hundreds of thousands of migratory birds smash into the city’s buildings every year. The city council just passed a bill to cut back on the carnage.

  4. A photo of a police officer in El Paso, Texas.
    Equity

    What New Research Says About Race and Police Shootings

    Two new studies have revived the long-running debate over how police respond to white criminal suspects versus African Americans.

  5. How To

    Want Solar Panels on Your Roof? Here's What You Need to Know

    A handy reference for navigating an emerging industry.

×