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2015 equinox: Sun rises due east and sets due west

January 17, 2015 sunset by Helio de Carvalho Vital.

January 17, 2015 sunset by Helio de Carvalho Vital.

The March 2015 equinox happens on March 20 at 22:45 Universal Time, which is 5:45 p.m. Central Daylight Time for us in the central U.S. The March equinox signals the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. On this day, the sun rises due east and sets due west.

Supermoon total eclipse of equinox sun on March 20

Total eclipse of the sun on November 11, 2012.  Image via NASA

Total eclipse of the sun on November 11, 2012. Image via NASA.

When the new moon closely aligns with one of its nodes, the moon’s dark umbral shadow falls on Earth, presenting a total eclipse of the sun. [/caption]
On March 20, the larger-than-average new supermoon swings right in front of the sun to totally block out the solar disk. Although you have to be at the just right spot on Earth to witness this total eclipse of the sun (Faroe Islands and the Svalbard archipelago), a much larger swath of the world gets to see varying degrees of a partial solar eclipse (Greenland, Iceland, Europe, northern Africa, the Middle East and northwestern Asia). Remember to use proper eye protection!

Regulus is the Lion’s Heart

Regulus and Leo I dwarf galaxy.  Image Credit: Russell Croman

Regulus and Leo I dwarf galaxy. Image Credit: Russell Croman

Yay Regulus! It’s the brightest star in the constellation Leo the Lion, depicting the Lion’s heart! This blue-white beauty of a star is the only 1st-magnitude star to sit almost squarely on the ecliptic, or path of the sun, moon and planets across our sky. It’s part of a noticeable pattern of stars. And, for us in the Northern Hemisphere, it’s evening appearance heralds the coming of spring. Follow the links inside to learn more about Regulus.

Westward shift of Orion and all the stars

Orion in the Canopy - Summit County, Colorado.  Photo posted to EarthSky Facebook in March 2015 by Daniel McVey.  Visit Photography by Daniel McVey.

Orion in the Canopy – Summit County, Colorado. Photo posted to EarthSky Facebook in March 2015 by Photography by Daniel McVey.

If you watch over several weeks, you can notice the constellation Orion moving steadily westward. In other words, it appears to move closer to the sunset each night. The westward shift of the stars throughout the seasons is due to Earth’s motion in orbit around the sun. Earth’s motion in orbit causes our night sky to point out an ever-shifting panorama of the galaxy.

Everything you need to know: Vernal equinox 2015

Happy equinox, everyone! The March equinox signals the beginning of spring in the Northern Hemisphere and autumn in the Southern Hemisphere. It marks that special moment when the sun crosses the celestial equator going from south to north. This year’s equinox arrives today at 22:45 UTC, or 5:45 p.m. Central Daylight Time for us in the central U.S. Click inside for more details, and a link to translate to your time zone.

Old moon before sunrise March 18

2015-march-17-moon-night-sky-chart

Tomorrow morning, on March 18, may be the last chance for people at northerly latitudes to see the old waning crescent moon in the March 2015 morning sky. However, if you live in the Southern Hemisphere or the northern tropics, you have a good chance of spotting the waning crescent moon before sunrise on both March 18 and 19. The moon will turn new on March 20, on the same day as the equinox, to transition out of the morning sky and into the evening sky.

Summer Triangle, signpost for all seasons

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The three brilliant stars of the Summer Triangle – Vega, Deneb and Altair – are out for at least part of the night every night of the year. Presently, the Summer Triangle shines in the east before dawn. Why does its location in the sky change? It changes because Earth is orbiting the sun, and our night sky is pointing out an ever-changing panorama of stars.

A puzzling star called Epsilon Aurigae

A possible model for the Epsilon Aurigae system.  One star eclipses the other, and the eclipsing star is surrounding by a dark cloud of gas and dust.   Image via NASA/JPL-Caltech.

A possible model for the Epsilon Aurigae system. One star eclipses the other, and the eclipsing star is surrounding by a dark disk of dust. Image via NASA/JPL-Caltech.

One of the most puzzling stars in all the heavens is the star Epsilon in the constellation Auriga the Charioteer. In cycles of 27 years, Epsilon Aurigae light dims for a period of about two years. The star’s last dimming was from 2009 to 2011. Astronomers studied it intently … but didn’t solve its mysteries.

A tangle of stars in Berenice’s Hair

Coma_Berenices

The constellation Coma Berenices contains the Coma star cluster. This is an open cluster, a loose collection of stars held together by gravity. It is near the constellation Leo the Lion, at the place where you might see a “puff” at the end of the Lion’s tail, you’ll notice a fuzzy patch not too far away from Denebola. This is the constellation Coma Berenices, or Berenice’s Hair.

Use Big Dipper to locate Hunting Dogs

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You can easily locate the Big Dipper in the northeast sky on these March evenings. The Big Dipper is part of the constellation Ursa Major, the Greater Bear.

And, if you can find the Big Dipper, you can also find two Hunting Dogs seen by the ancient stargazers to be nipping at the Bear’s heels. The Hunting Dogs are a separate constellation: tiny Canes Venatici. You’ll need a dark sky to see these two little stars snuggled in the arc of the Big Dipper. Originally, they were called Asterion and Chara. But the eastern star is now called Cor Caroli, or Heart of Charles, named for the patron king of the Polish astronomer Johannes Hevelius, who devised this constellation in 1690.

The most famous object in this region of the sky is M51, the Whirlpool Galaxy. It is beautiful when seen through telescopes and appears dramatic in photographs.