Moon to appear larger during ‘brush' with Earth on March 19

The cow won't be able to finally jump over the moon.

But it might look like a possibility Saturday, when the moon will be at its closest approach to Earth in 19 years. The moon will be about 9,000 miles nearer to us than usual — enough to make it appear just slightly larger, said Indian River State College planetarium director Jon Bell.

Here is how to see it and what is behind this celestial close "brush" with the Earth.

VIEWER'S GUIDE

The full moon should be fully visible by 8 p.m. Saturday and the current weather forecast calls for a mostly clear sky. The moon will be almost as full on Friday.

For best effect look early when the moon is at the horizon. Then, an everyday optical illusion makes the moon appear huge because it is in contrast with the horizon, Bell said. The moon appears to shrink as it goes up into the sky.

People who really want to be moonstruck can peer through telescopes that the Treasure Coast Astronomical Society will set up, weather permitting, around 7:30 p.m. Friday outside Indian River State College's Hallstrom Planetarium in Fort Pierce.

There is no charge for use of the telescopes, but while you're there, you might want to see the planetarium's show, "The Stars of the Pharaohs," which is at 7 and 8 p.m. Hallstrom Planetarium is at IRSC's main campus, 3209 Virginia Ave.

SPACE SCIENCE 101

The moon's 28-day orbit is elliptical: at times it is closer or farther from Earth.

On average, the moon's closest-to-Earth orbit is 230,000 miles. But occasionally it comes within about 221,000 miles, as it will Saturday.

And this week's approach is coming at a full moon, when the moon is at its brightest.

Sunlight causes the to moon shine; during a full moon the sun and moon are opposite sides of the Earth so sunlight fully illuminates the moon's Earth-facing surface for a while.

CHAOS-CAUSING SUPER MOON?

Astrologer Richard Nolle coined the term "super moon" to refer to any time the full or new moon was at 90 percent or more of its closest orbit to Earth. Saturday, the moon will be at 100 percent.

Nolle and other astrologers warn that super moons can cause natural disasters such as earthquakes and tidal surges. Some have even tried to link the Japan earthquake with Saturday's super moon, though most scientists say there is no correlation.

Accuweather.com reports that super moons have occurred in 1955, 1974, 1992 and 2005.

TUG ON TIDES

Tides will be almost a foot higher and lower because of the sun and moon being on the opposite side of the planet, each exerting a gravitational tug on the oceans.

That means stronger tidal currents that can alter sandbars, potentially creating some rip currents, according to National Weather Service forecaster Scott Kelly. Coastal flooding isn't expected because the forecast is for calm weather.

IF YOU MISS IT

Don't despair. The moon's closest-to-Earth orbit occurs annually so it will be back almost as close a year from now, said Allen Como with the Treasure Coast Astronomical Society.