The Christmas Star, a rare celestial event associated with the...

The Christmas Star, a rare celestial event associated with the biblical Star of Bethlehem will hit its peak and be visible over Long Island's western skies shortly after sunset on Dec. 21. Credit: Charles and Helen Reichert Planetarium/Vanderbilt/Dave Bush

Long Islanders will be treated to an extremely rare celestial phenomenon, when the Christmas Star — also known as the star of Bethlehem — appears over Long Island for the first time since the Middle Ages in a celestial event that starts this week and culminates Dec. 21, the winter solstice.

Last seen 794 years ago and known to modern astronomers as the great conjunction, the Christmas Star occurs when the giant planets Jupiter and Saturn — which lie hundreds of millions of miles apart in our solar system — appear so close together in the night sky that they look like one bright object, said Dave Bush, Director of the Vanderbilt’s Charles and Helen Reichert Planetarium in Centerport.

Known popularly as the Christmas Star, it’s thought to be the same heavenly phenomenon as the star of Bethlehem, which guides The Magi’s travel to Jerusalem in the Gospel of Matthew’s Nativity story, Bush said.

Long Islanders don’t have to wait until Christmas to open this celestial gift. You can watch through binoculars, a telescope or with the naked eye, "every clear night as they (Jupiter and Saturn) get closer and closer, low in the west after sunset," said Sue Rose of East Meadow, president of the Amateur Observers’ Society of New York.

The planets will appear close enough to be seen through one telescope field of view, when the Christmas Star effect peaks on Dec. 21, the winter solstice.

That night, stargazers without permits will be able to view the Christmas Star at Robert Moses State Park Field 2 in Babylon, Jones Beach State Park Field 6 in Wantagh, Sunken Meadow State Park Field 3 in Kings Park and Montauk Point State Park upper parking lot, said George Gorman Jr., Long Island regional director, Office of Parks, Recreation and Historic Preservation. The parking fields will remain open until midnight.

Newsday LogoSUBSCRIBEUnlimited Digital AccessOnly 25¢for 5 months