Sky Events – Page 4 – A Darker View

Transit of Mercury Nov 11, 2019

On November 11th, 2019 Mercury will transit the Sun. While transits of Mercury are not rare, they are not all that common either. The last transit was a few years ago in May of 2016. On average there are fourteen transits of Mercury each century or one every seven years. If you wish to observe one the situation is much better than transits of Venus which occur in pairs over a century apart.

Mercury Transit 9May2016 — Mercury transiting the Sun on May 9, 2016. Celestron C8 and Canon 6D at f/10.

This particular transit will favor observers in Europe, South America, and the eastern seaboard of North America where the entire transit will be visible. Unfortunately for observers in the islands only the final hour and a half of the transit will be visible having begun well before local dawn. Sunrise will occur around 06:28 for the island of Hawaiʻi, with the transit ending at 08:04 in the morning when the Sun will be 20° above the horizon.

New Moon

Young Moon — A very young moon over Waikoloa

New Moon will occur today at 17:38HST.

On the evening of the 29th, two days from now, look for a slim crescent Moon beside the brilliant Venus in the sunset.

Mercury at Maximum Elongation

An evening conjunction of Mercury, Venus and Jupiter on 30 May, 2013

Today Mercury is passing through maximum elongation, the furthest it will rise above the setting Sun in the evening sky. After today the planet will slide back into the Sun’s glare headed for inferior conjunction on November 11th.

This is a good apparition, with the planet over 24° from the Sun at maximum.

Full Moon

Full Moon will occur today at 11:08HST.

This evening look for the Moon rising in the east just as the Sun sets in the west. Across the Big Island this can often lead to moonbows as the low elevation moonlight interacts with fog and clouds.

New Moon

New Moon will occur today at 08:26HST.

Tonight offers the best dark Saturday for observing this month. Get out and enjoy the dark!

Autumnal Equinox

The fall equinox will occur at 21:50HST today.

The equinox is defined as the time at which the Sun passes through the plane of the Earth’s equator. Until the next spring equinox occurs in 2020, the Sun will be located in the southern hemisphere with a negative declination coordinate.

Today the length of the day and night will be very near equal, thus the term equinox. the Sun will rise and set nearly exactly due east and due west.

Today is considered the start of fall for most cultures in the northern hemisphere, or the start of spring for those in the southern hemisphere.

2019 Apsides and Seasons
Event	Universal Time		Hawaii Standard Time
Perihelion	Jan 03	05:20UT	Jan 02	19:20HST
Spring Equinox	Mar 20	21:58UT	Mar 20	11:58HST
Summer Solstice	Jun 21	15:54UT	Jun 21	05:54HST
Aphelion	Jul 04	22:11UT	Jul 04	12:11HST
Fall Equinox	Sep 23	07:50UT	Sep 22	21:50HST
Winter Solstice	Dec 22	04:19UT	Dec 21	18:19HST
Data from US Naval Observatory Data Services

Full Moon

Full Moon will occur today at 18:33HST.

This evening look for the Moon rising in the east just as the Sun sets in the west. Across the Big Island this can often lead to moonbows as the low elevation moonlight interacts with fog and clouds.

Neptune at Opposition

Today the planet Neptune will pass through opposition, directly opposite the Sun in our sky. The planet will be well placed for observation all night long, rising at sunset, transiting at midnight, and setting at sunrise. If you are looking to observe Neptune, it is currently shining at magnitude 7.8 in the center of the constellation Aquarius.

Neptune from Voyager 2, Credit: NASA /JPL

As the outer planets Uranus and Neptune move so slowly across the sky, the timing of oppositions is driven by the Earth’s orbit and occur each year at nearly the same time. Neptune’s orbital period is 164.8 years, taking over a century and a half to circle the celestial globe once. As Neptune was discovered in 1846, it has completed a little over one orbit since discovery.

Venus Appears in the Sunset

Crescent Venus — Venus approaching inferior conjunction, 24Dec2013

Over the next weeks Venus will appear above the sunset. Look for a brilliant, star-like object low in the glow of sunset, right above the setting Sun.

Over the following months the planet will rise high above the sunset, reaching maximum elongation on March 24th, 2020.

When Venus does reappear we can expect a few UFO reports by people unfamiliar with the normal workings of our skies. In late 2018, when it last emerged in the dawn we had a few such reports here on the island, including a very nice video and folks who could not accept the fact that the “strange light” was simply a bright planet.

Rising with Venus on this particular apparition is Mercury, the pair getting higher each evening until Mercury reaches maximum elongation on October 19th.

Mercury at Superior Conjunction

Today Mercury is passing through superior conjunction, passing around the far side of the Sun as seen from our earthbound vantage point. This fast moving planet will reappear in the sunset in about a week, rising towards maximum elongation on October 20th.

This will be a good apparition of mercury reaching over 24° from the Sun.

Mercury Events for 2019
Apparition	Date	Elongation	Magnitude
Evening	Feb 27	18.1°E	-0.2
Morning	Apr 11	27.7°W	+0.6
Evening	Jun 23	25.2°E	+0.7
Morning	Aug 9	19.0°W	+0.3
Evening	Oct 20	24.6°E	+0.1
Morning	Nov 28	20.1°W	-0.3
Data from the Mercury Chaser’s Calculator by John Walker