Tonight – April 30, 2015 – as evening dusk deepens into darkness, look westward to spot the planet Mercury with the Pleiades star cluster (chart below). Then look for the bright waxing gibbous moon, near to Spica, brightest light in the constellation Virgo (chart above). Follow the links below to learn more:
Seeing Mercury and the Pleiades
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On any evening in late April and early May, draw an imaginary line from Jupiter through Venus to spot Mercury near the horizon. The green line depicts the ecliptic
View larger. | EarthSky Facebook friend Niko Powe in Kewanee, Illinois caught this photo on April 28, 2015. He wrote: “Front row seats to this ALL-STAR line-UP in the western sky after sunset… and I FINALLY got a glimpse of Mercury!!!” Thanks and congrats, Niko! To all … notice that Orion’s Belt more or less points to Mercury.
Seeing Mercury and the Pleiades. Look for them early, because Mercury and the Pleiades will sink below the western horizon by nightfall or early evening (approximately 100 minutes after sunset at mid-northern latitudes). Not sure you’re seeing Mercury? Here’s a tip. As night falls, there are two very bright planets visible. Venus is brighter and closer to the western horizon. Jupiter is a bit fainter – but brighter than all the stars – and higher in the sky. Draw a line between Jupiter and Venus – aimed down toward the sunset point in the west – and Mercury should be there, assuming it hasn’t already set.
It helps to have an unobstructed horizon in the direction of sunset for spotting Mercury. Although this late April and early May evening apparition of Mercury counts as a favorable one for the Northern Hemisphere, the solar system’s innermost planet still looms close to the horizon and sits in the glare of evening twilight.
Binoculars may be helpful, especially for spotting the Pleiades star cluster – a dipper-shaped pattern – near Mercury now on the sky’s dome.
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Seeing the moon and Spica. You’ll have plenty of time to catch the waxing gibbous moon and Spica, the brightest star in the constellation Virgo the Maiden, after dark. The moon and Spica will be out nearly all night long. They’ll set in the southwest sky in the wee hours before dawn.
The moon and Spica will move westward across the sky tonight for the same reason that the sun moves westward across the sky during the day. The Earth rotates on its axis from west to east, making it appear as if the moon and Spica are moving westward while the Earth remains at rest. However, it’s really the Earth that’s doing the moving.
You can actually discern the moon’s true orbital motion by noting the moon’s change of position relative to Spica over the next few days. Each day, the moon moves an average of 13o eastward in front of the backdrop stars. The moon goes full circle through the constellations of the Zodiac in about 27 days.
Bottom line: As darkness falls on the evening of April 30, 2015, look first for Mercury and the Pleiades low in the western sky, and then for the moon and Spica in the southeast.
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Tonight – April 30, 2015 – as evening dusk deepens into darkness, look westward to spot the planet Mercury with the Pleiades star cluster (chart below). Then look for the bright waxing gibbous moon, near to Spica, brightest light in the constellation Virgo (chart above). Follow the links below to learn more:
Seeing Mercury and the Pleiades
Donate: Your support means the world to us
On any evening in late April and early May, draw an imaginary line from Jupiter through Venus to spot Mercury near the horizon. The green line depicts the ecliptic
View larger. | EarthSky Facebook friend Niko Powe in Kewanee, Illinois caught this photo on April 28, 2015. He wrote: “Front row seats to this ALL-STAR line-UP in the western sky after sunset… and I FINALLY got a glimpse of Mercury!!!” Thanks and congrats, Niko! To all … notice that Orion’s Belt more or less points to Mercury.
Seeing Mercury and the Pleiades. Look for them early, because Mercury and the Pleiades will sink below the western horizon by nightfall or early evening (approximately 100 minutes after sunset at mid-northern latitudes). Not sure you’re seeing Mercury? Here’s a tip. As night falls, there are two very bright planets visible. Venus is brighter and closer to the western horizon. Jupiter is a bit fainter – but brighter than all the stars – and higher in the sky. Draw a line between Jupiter and Venus – aimed down toward the sunset point in the west – and Mercury should be there, assuming it hasn’t already set.
It helps to have an unobstructed horizon in the direction of sunset for spotting Mercury. Although this late April and early May evening apparition of Mercury counts as a favorable one for the Northern Hemisphere, the solar system’s innermost planet still looms close to the horizon and sits in the glare of evening twilight.
Binoculars may be helpful, especially for spotting the Pleiades star cluster – a dipper-shaped pattern – near Mercury now on the sky’s dome.
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Seeing the moon and Spica. You’ll have plenty of time to catch the waxing gibbous moon and Spica, the brightest star in the constellation Virgo the Maiden, after dark. The moon and Spica will be out nearly all night long. They’ll set in the southwest sky in the wee hours before dawn.
The moon and Spica will move westward across the sky tonight for the same reason that the sun moves westward across the sky during the day. The Earth rotates on its axis from west to east, making it appear as if the moon and Spica are moving westward while the Earth remains at rest. However, it’s really the Earth that’s doing the moving.
You can actually discern the moon’s true orbital motion by noting the moon’s change of position relative to Spica over the next few days. Each day, the moon moves an average of 13o eastward in front of the backdrop stars. The moon goes full circle through the constellations of the Zodiac in about 27 days.
Bottom line: As darkness falls on the evening of April 30, 2015, look first for Mercury and the Pleiades low in the western sky, and then for the moon and Spica in the southeast.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
from EarthSky http://ift.tt/1DLYymi
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