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No double moon in 2018, or ever

2018 will be an excellent year to view Mars. The planet will be closer to Earth – and brighter in our sky – than since 2003. But as big as the moon? Heck no.

Lengths of lunar months in 2018

This new moon ends the longest lunar month of the 21st century and begins the longest lunar month of 2018.

Best photos: Morning planets!

On Sunday morning, Jupiter and Mars were half a moon-diameter apart. Now the moon is sweeping past. Plus Mercury and Saturn are in conjunction this weekend. Photos here.

Close and far moons in 2018

In 2018, the moon swings farthest from Earth for the year on January 15, only 2 weeks after coming closest to Earth for the year on January 1.

EarthSky’s 2018 meteor shower guide

Plan ahead now for an awesome year of meteor-watching. Good news! In 2018, the year’s 2 most reliable showers – August Perseids and December Geminids – happen with little to no interference from the moon.

Sun in zodiac constellations, 2018

Sun-entry dates to zodiac constellations in 2018, using boundaries for constellations set by International Astronomical Union in 1930s.

January guide to the bright planets

The moon is pointing toward Mercury and Saturn on the mornings of January 13 and 14, 2018. Afterwards, Mercury will fall toward the sunrise day by day, while Saturn will climb upward, away from the glare of daybreak.

Mars brighter in 2018 than since 2003

In 2003, Mars was closer and brighter in our sky than in nearly 60,000 years. In 2018, Mars will be at its brightest since then! Start watching Mars now.

Are December’s solstice and January’s perihelion related?

December solstice 2017 was December 21. Earth is closest to the sun for 2018 on January 2-3. Coincidence?

Super effect on us from supermoons?

A supermoon’s extra pull of gravity creates higher-than-usual tides. But the moon’s pull doesn’t affect a human body nearly as powerfully as it does an ocean.

Moonlight for 2018 Quadrantid meteors

The 2018 Quadrantid meteor shower is expected to exhibit its narrow peak January 3 around 21-22 hours UTC. The full supermoon nearly coincides, and moonlight will interfere with the shower.

See brightest star Sirius at midnight on New Year’s Eve

Dog Star Sirius reaches its highest point in the sky around midnight every New Year. For this reason, it might also be called the New Year’s star.

Star of the week: Aldebaran

Aldebaran – brightest star in Taurus the Bull – is huge! If it replaced our sun, its surface would extend almost to the orbit of Mercury.

Was the Christmas Star real?

Some possible astronomical explanations for the Star of Bethlehem or Christmas star.

Solstice arrives December 21

December solstice 2017 arrives on December 21 at 16:28 UTC. High summer for the Southern Hemisphere. For the Northern Hemisphere, the return of more sunlight!

Watch for Ursid meteors

Ursid meteor shower active each year around December solstice. In 2017, the peak is probably Friday morning, December 22.

Solstice tale of two cities

December solstice sunrise comes at the same time for St. Augustine, Florida and New York City. But St. Augustine has an hour more of daylight than New York. Here’s why.

Slowest sunsets around solstices

Here’s a natural phenomenon you might never have imagined. That is, the sun actually sets more slowly around the time of a solstice.

Mysterious rock-comet 3200 Phaethon was closest to Earth December 16

This asteroid-comet hybrid is why the Geminid meteors put on a good show in 2017. Info and images of the rock-comet here.

Lengths of lunar months in 2017

Longest lunar month of 21st century (2001 to 2100) starts with December 18 new moon. It’s also the farthest new moon of the year. Coincidence?