In mid-August 2015, Venus – the second planet outward from the sun and brightest planet visible in Earth’s sky – swung in between Earth and the sun. At that time, Venus transitioned out of Earth’s evening sky and into our morning sky. Unless you have special equipment, you probably haven’t seen Venus for a few weeks.
After having been lost in the sun’s glare for several weeks, Venus returns to visibility in the morning sky this week (beginning around August 26, 2015). On that approximate date – or on a morning around that date – you might see Venus climbing up above the eastern horizon an hour or so before sunrise – if you have an unobstructed eastern horizon and clear sky.
If you miss Venus this week, look for it to appear in the morning sky someday soon.
What will Venus look like before dawn? Here it is shortly before it slipping into the sunset in early August. This is Venus (brightest), Jupiter and Mercury low in the twilight on August 3, 2015. Photo by Peter Lowenstein in Mutare, Zimbabwe.
Just don’t mistake Sirius – the brightest star of the nighttime sky – for the planet Venus. Sirius sparkles in the southeast, while Venus shines with a steadier light almost due east. Although Venus is actually brighter than Sirius, Venus might be the harder of the two to spot in the morning sky right now, because Venus sits closer to the glare of sunrise. Click here for more information about Sirius in the morning sky.
The illustration below enables you to get some perspective of Venus’ and Earth’s orbits around the sun. We’re looking down upon the plane of the solar system from the north side. From this vantage point, the planets revolve counter-clockwise around the sun.
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Not to scale. The radius of Venus’ orbit is about 0.72 of Earth’s distance from the sun (0.72 of an astronomical unit).
The passage of Venus between the Earth and sun took place on August 15, 2015. Astronomers call this an inferior conjunction of Venus. At such times, Venus in its smaller and swifter orbit passes in between the Earth and sun. We should mention that only planets that orbit the sun inside of Earth’s orbit (Mercury and Venus) have inferior conjunctions.
After inferior conjunction, Venus always moves westward of the rising sun in our sky until reaching its greatest western elongation (46o) – farthest angular distance from the rising sun – some 72 days later.
Venus will next reach greatest western (morning) elongation on October 26, 2015. It’ll look like a miniature half-lit quarter moon through the telescope. That’s because Venus’ disk always appears about 50% illuminated by sunshine at any greatest elongation.
Midway between inferior conjunction and greatest western elongation, Venus will shine at its brightest as the morning “star” on September 21, 2015. That’s in spite of the fact that Venus’ disk is only about one-quarter illuminated by sunshine whenever it’s midway between an inferior conjunction and a greatest elongation.
This brilliant world will remain in the morning sky until reaching superior conjunction on June 6, 2016, to transition back into the evening sky.
Bottom line: Starting around August 26, 2015, start watching for dazzling Venus to illuminate the sky before sunrise.
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In mid-August 2015, Venus – the second planet outward from the sun and brightest planet visible in Earth’s sky – swung in between Earth and the sun. At that time, Venus transitioned out of Earth’s evening sky and into our morning sky. Unless you have special equipment, you probably haven’t seen Venus for a few weeks.
After having been lost in the sun’s glare for several weeks, Venus returns to visibility in the morning sky this week (beginning around August 26, 2015). On that approximate date – or on a morning around that date – you might see Venus climbing up above the eastern horizon an hour or so before sunrise – if you have an unobstructed eastern horizon and clear sky.
If you miss Venus this week, look for it to appear in the morning sky someday soon.
What will Venus look like before dawn? Here it is shortly before it slipping into the sunset in early August. This is Venus (brightest), Jupiter and Mercury low in the twilight on August 3, 2015. Photo by Peter Lowenstein in Mutare, Zimbabwe.
Just don’t mistake Sirius – the brightest star of the nighttime sky – for the planet Venus. Sirius sparkles in the southeast, while Venus shines with a steadier light almost due east. Although Venus is actually brighter than Sirius, Venus might be the harder of the two to spot in the morning sky right now, because Venus sits closer to the glare of sunrise. Click here for more information about Sirius in the morning sky.
The illustration below enables you to get some perspective of Venus’ and Earth’s orbits around the sun. We’re looking down upon the plane of the solar system from the north side. From this vantage point, the planets revolve counter-clockwise around the sun.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
Not to scale. The radius of Venus’ orbit is about 0.72 of Earth’s distance from the sun (0.72 of an astronomical unit).
The passage of Venus between the Earth and sun took place on August 15, 2015. Astronomers call this an inferior conjunction of Venus. At such times, Venus in its smaller and swifter orbit passes in between the Earth and sun. We should mention that only planets that orbit the sun inside of Earth’s orbit (Mercury and Venus) have inferior conjunctions.
After inferior conjunction, Venus always moves westward of the rising sun in our sky until reaching its greatest western elongation (46o) – farthest angular distance from the rising sun – some 72 days later.
Venus will next reach greatest western (morning) elongation on October 26, 2015. It’ll look like a miniature half-lit quarter moon through the telescope. That’s because Venus’ disk always appears about 50% illuminated by sunshine at any greatest elongation.
Midway between inferior conjunction and greatest western elongation, Venus will shine at its brightest as the morning “star” on September 21, 2015. That’s in spite of the fact that Venus’ disk is only about one-quarter illuminated by sunshine whenever it’s midway between an inferior conjunction and a greatest elongation.
This brilliant world will remain in the morning sky until reaching superior conjunction on June 6, 2016, to transition back into the evening sky.
Bottom line: Starting around August 26, 2015, start watching for dazzling Venus to illuminate the sky before sunrise.
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky http://ift.tt/1U3HCVv
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