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Best time to see Saturn is here!

Let brilliant Mars guide you to the planet Saturn and the star Antares for months to come.

Let brilliant Mars guide you to the planet Saturn and the star Antares for months to come.

Tonight – or any night in late May 2016 – start watching for the ringed planet Saturn, which is found near the planet Mars and the star Antares. Saturn comes closest to Earth for the year on Friday, June 3 – only four days after Mars’ closest approach to Earth on Monday, May 30. It’s coming up fairly early in the evening now, and its best time to be observed in all of 2016 is nearly upon us.

Where is the moon? Last quarter

May 29, 2016 last quarter moon posted to EarthSky Facebook by Deirdre Horan in Dublin, Ireland. Thanks, Deirdre! Look for the last quarter moon to rise at midnight and to be overhead at dawn.

May 29, 2016 last quarter moon posted to EarthSky Facebook by Deirdre Horan in Dublin, Ireland. Thanks, Deirdre!

The last quarter moon comes on May 29, 2016 at 12:12 UTC. A last quarter moon looks half-illuminated. It rises around midnight, appears at its highest in the sky at dawn, and sets around noon.

Life ingredients in Rosetta’s comet!

This single frame from Rosetta’s navigation camera of Comet 67P/Churyumov–Gerasimenko Read more about this image from ESA.

Rosetta’s navigation camera captured this single frame of Comet 67P/Churyumov–Gerasimenko on March 25, 2015, a few days before a flyby that would bring the spacecraft to within about 10 miles (15 km) of the comet. It was during this flyby, on March 28, that Rosetta made a detection of the amino acid glycine in the comet’s ‘atmosphere’, or coma. Image via ESA.

The Rosetta spacecraft has identified the chemical elements glycine and phosphorus in the dusty halo around Comet 67P/Churyumov–Gerasimenko. Scientists say the discovery is “the first unambiguous detection of glycine at a comet” and provides further evidence supporting the theory that the building blocks for life came to Earth from outer space.

Is dark matter made of black holes?

Artist's concept of primordial black holes, via NASA.

Artist’s concept of primordial black holes, via NASA.

What if if dark matter consisted of a population of black holes similar to those detected by LIGO last year? A new study analyzes this possibility.

Clues to birth of supermassive black holes

This artist’s impression shows a possible seed for the formation of a supermassive black hole. Two of these possible seeds were discovered by an Italian team, using three space telescopes: the NASA Chandra X-ray Observatory, the NASA/ESA Hubble Space Telescope, and the NASA Spitzer Space Telescope. Image via NASA/CXC/M. Weiss

This artist’s impression shows a possible seed for the formation of a supermassive black hole. Two of these possible seeds were discovered by an Italian team, using three space telescopes: the NASA Chandra X-ray Observatory, the NASA/ESA Hubble Space Telescope, and the NASA Spitzer Space Telescope. Image via NASA/CXC/M. Weiss

Astrophysicists have taken a major step forward in understanding how these monster black holes are born.

How do hurricanes get their names?

Hurricane Alex as seen on January 14, 2016, by the the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Image via NASA Earth Observatory.

Hurricane Alex as seen on January 14, 2016, by the the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. Image via NASA Earth Observatory.

Ever wonder how hurricanes get their names? And why do hurricanes have names at all? For one thing, meteorologists long ago learned that naming tropical storms and hurricanes helps people remember the storms. Find out more, plus hurricane names for 2016, inside.

Saturn’s south polar vortex

Image credit: NASA/JPL/Space Science Institute

Image of Saturn’s south polar vortex, 10 times more detailed than any previous image. Image via NASA/JPL/Space Science Institute.

A monstrous vortex sits at Saturn’s south pole. It’s not just beautiful. It also lets astronomers peer deep into Saturn’s dense atmosphere.

Best close-up of Pluto’s surface

Image via NASA/JHUAPL/SwRI

Image via NASA/JHUAPL/SwRI

The most detailed view of Pluto’s terrain you’ll see for a very long time, taken by the New Horizons spacecraft as it flew past Pluto on July 14, 2015.

Half-lit last quarter moon on May 29

Last quarter moon

Last quarter moon

Enjoy the January 29, 2016 last quarter moon! And know that the Earth and moon are like mirrors to each other in that – when we see a last quarter moon in our sky – those on the moon would see a first quarter Earth.

Four keys to understanding moon phases

This morning's waning gibbous moon - December 29, 2015 - from Deirdre Horan in Ireland.

This morning’s waning gibbous moon – December 29, 2015 – from Deirdre Horan in Ireland.

Why does the moon seem to change its shape every night? Remember that the moon is a world in space with a day side and a night side.