Mercury at Maximum Elongation

Today Mercury will be at maximum eastern elongation, as high in the evening sky as it will appear for this current apparition. After today the planet will slide back into the sunset, passing through inferior conjunction on August 26th to reappear in the morning sky in mid-September.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Mercury typically completes three morning and three evening apparitions in each year. While the innermost planet never gets very far from the Sun, maximum elongation represents the best time to observe Mercury as high in the sky as possible.

There are no transits of Mercury in 2017, the next will be Nov 11, 2019.

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Mercury at Superior Conjunction

Today Mercury will be at superior conjunction. After today the planet will reappear in the evening sky, rising high enough from the Sun’s glow to be seen early next month.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Superior conjunction is when the planet passes around the far side of the Sun as seen from Earth. For a few weeks the planet will be lost in the Sun’s glare, hidden from view.

As Mercury is on an orbit inside that of Earth’s it will see both inferior and superior conjunctions as it passes from the evening sky to the dawn sky and back again.

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Mercury at Maximum Elongation

Today Mercury will be at maximum western elongation, as high in the morning sky as it will appear for this current apparition. After today the planet will slide back into the dawn, passing through superior conjunction on June 21st to reappear in the evening in mid-July.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
This will be the best morning apparition of the inner planet for 2016. The best evening apparition of 2017 will be in July, with a maximum elongation of over 27°.

There are no transits of Mercury in 2017, the next will be Nov 11, 2019.

Continue reading “Mercury at Maximum Elongation”

Mercury at Inferior Conjunction

Today Mercury will be at inferior conjunction. After today the planet will reappear in the dawn, rising high enough from the Sun’s glow to be seen around the end of the month.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Inferior conjunction is when the planet passes between the Sun and the Earth. As such the only planets to see inferior conjunction are Mercury and Venus. A transit is possible if the planet passes directly in front of the Sun, but normally this alignment does not occur, the planet passing above or below the Sun as seen from the Earth. There are no transits of Mercury in 2017, the next will be Nov 11, 2019.

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Mercury at Maximum Elongation

Today Mercury will be at maximum eastern elongation, as high in the evening sky as it will appear for this current apparition. After today the planet will slide back into the sunset, passing through inferior conjunction on April 19th to reappear in the morning sky around the end of the month.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Mercury typically completes three morning and three evening apparitions in each year. While the innermost planet never gets very far from the Sun, maximum elongation represents the best time to observe Mercury as high in the sky as possible.

There are no transits of Mercury in 2017, the next will be Nov 11, 2019.

Continue reading “Mercury at Maximum Elongation”

Mercury at Superior Conjunction

Today Mercury will be at superior conjunction. After today the planet will reappear in the evening sky, rising high enough from the Sun’s glow to be seen around the end of the month.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
Superior conjunction is when the planet passes around the far side of the Sun as seen from Earth. For a few weeks the planet will be lost in the Sun’s glare, hidden from view.

As Mercury is on an orbit inside that of Earth’s it will see both inferior and superior conjunctions as it passes from the evening sky to the dawn sky and back again.

Continue reading “Mercury at Superior Conjunction”

Mercury at Maximum Elongation

Today Mercury will be at maximum western elongation, as high in the morning sky as it will appear for this current apparition. After today the planet will slide back into the dawn, passing through superior conjunction on March 6th to reappear in the evening around the end of March.

Mercury Transit 9May2016
Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.
The best evening apparition of 2017 will be in July, with a maximum elongation of over 27°. The best morning apparition will be May at over 25°, with today being nearly as good at over 24°.

There are no transits of Mercury in 2017, the next will be Nov 11, 2019.

Continue reading “Mercury at Maximum Elongation”

The Moon and Jupiter

This evening at sunset a nice crescent Moon and the bright planet Jupiter will be quite close. As sunset around 19:00 the two will be separated by a mere 46′, just a little over the width of the full Moon. The two should make a very attractive pair as they sit above the glow of sunset.

Keep an eye out for Mercury and Venus closer to the horizon. At 19:00 Venus will be 9° above the horizon with Mercury a bit higher at 14°. The Moon and Jupiter will be higher yet around 25°. Since Mars and Saturn are also visible in the southern sky all five naked eye planets will be visible.

All Five Planets Visible

For much of the month all five naked eye planets will be visible at sunset. Mercury, Venus, Mars, Saturn, and Jupiter can all be seen easily if one knows where to look. Indeed, four of the five are quite bright and quite hard to miss. Neptune and Uranus are generally too faint to be seen without optical aid.

Conjunction
Venus and Jupiter over the Keck 1 dome
Tonight, August 1st, Venus is just rising high enough to be easily seen. It will be a mere 5° above the horizon at 19:30, probably bright enough to be seen against the glow. You can find Mercury a little higher, about 10° above the horizon. Jupiter is obvious well above the sunset as a bright object shining at -1.7 magnitude. Mars and Saturn are visible to the south on the top of Scorpio.

There will be a nice conjunction of the Moon and Jupiter, only 46′ apart, on the 5th of August. Mercury reaches eastern elongation on the 16th of the month. A beautiful triplet of Mercury, Venus, and Jupiter will gather in the days around the 22nd. Keep an eye to the sky for the month to be treated to some nice planetary views.

Mercury and Venus

The two inner planets will rendezvous in the sunset over the next few days. Venus appeared in the sky a few days ago having just emerged from superior conjunction. Mercury will emerge quickly from the solar glare to pass Venus only 10° from the Sun. This conjunction will be quite low and a bit in the bright glow of sunset, perhaps somewhat challenging to spot.

This evening the two will be about 2° apart, and will quickly converge. On July 16th the two will be only 32′ apart, about the diameter of a full Moon. After that the two will quickly separate. Interestingly on the 17th the pair will pass through the M44 star cluster, though perhaps it will still be a bit bright to appreciate this dimmer cluster.

Late in the month this trio of bright planets will continue their dance in a set of conjunctions that lasts into September. The highlight will be on August 27 when Jupiter and Venus will pass within 12′ of each other while Mercury is only 5° away.

Moon and Mercury
The Moon appears as a thin crescent beside the planet Mercury, photo taken from the summit of Mauna Kea on 12Oct2007