Night_Skies_June_2005

Jeff Green | Jun 02, 2005

Night Skies June 2, 2005

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by Leo Enright

With the arrival of June in this part of the world, we can always expect to have our longest days and our shortest nights. On the day that is called the solstice (which, from its two Latin derivatives, means the sun standing still), namely June 21, the sun appears at its most northern location in the sky of any time during the whole year. If we watch its rising in the morning, we can easily see that it is now well north of the eastern point on the horizon, and if we watch its setting, we can also see that it sets well north of the western point on the horizon. Those who have watched solar risings and settings over several months know that, on the date just mentioned, those points are at their northern extremities, and beginning the next day, risings and settings will be slightly farther south along the horizon. Some people may have already noticed also that, for a couple of hours each day in late May and in June, both in the early morning and late evening, rays of sunlight actually shine through the north-facing windows of our houses. Locally Junes sunrise times range from 5:24 a.m. to 5:20 a.m., and sunset times from 8:46 p.m. to 8:57 p.m. The times of earliest sunrise and of latest sunset (a fact that is very surprising to many people) are very dependent on the latitude where one lives, and are NOT precisely on the date of the solstice. At our latitude, the date of the earliest sunrise is actually June 15 when it occurs a minute earlier (at 5:20 a.m.) than it does on June 21 (at 5:21 a.m.). The date of latest sunset here is June 27, and the sunset time (8:57 p.m.) on that date is a minute later than the sunset time on June 21 (8:56 p.m.).

The month of June, like May, always brings very long twilights. Locally in June, the first hint of morning twilight begins a few minutes before 3 a.m. during most of the month. Evening twilight lasts until well after 11 p.m. every night this month, with the latest end of twilight being about 11:28 p.m. in the week following June 21. In other words, at this latitude, in June there is a totally dark night sky for only about 3 hours, that is, from the end of evening twilight at about 11:25 p.m. until the beginning of morning twilight at about 2:55 a.m.

After many months of seeing only two bright planets in the evening sky, planet observers are able to look forward to a very rare treat this month. Three years ago, in April and May 2002, many may recall that they were able to observe an extremely rare line-up of all five of the bright planets in the evening sky. This month, in the evening sky, they will be able see four of those planets, and three of them will be in MUCH CLOSER to each other than any three planets have appeared in over 30 years!

Throughout June, the planet Jupiter will continue to dominate the southwestern sky among the bright stars of the constellation Virgo, and it will not set until about 1 a.m. Low in the northwestern sky is where the rare gathering of three bright planets will take place, and the time for viewing them is 45 minutes to an hour after sunset. This is such a rare event, and having a good, unimpeded view of the northwestern horizon is so important that observers should consider travelling to a better location if trees or buildings obstruct the view. As was the case last month, after sunset, the planet Saturn will continue to be seen to the left of the bright stars Castor and Pollux in the northwestern sky. Below them, brilliant Venus, the brightest planet of all, can be easily seen, beginning a half-hour after sunset. Note that from night to night, for the first 24 days of June, the planet Saturn, along with the stars Castor and Pollux, appears to move downward, and at the same time, brilliant Venus appears to move upward to meet its fellow-planet. On the night of June 24th, the two of them are side by side. After June 24, Venus, from night to night, appears to move above Saturn and on toward the stars of Cancer. In the last half of the month, Mercury comes to join in on the dance of Saturn and Venus. Beginning about a half-hour after sunset on June 15 or June 16, Mercury should be easily seen moving upward from below Saturn and Venus. From night to night, Mercury is seen closer and closer to the other two planets until on June 24, the three planets are amazingly close, side-by-side, and to the left of the stars Castor and Pollux. Continue to watch them every evening for the rest of the month, in order to see that, as they appear to move together above Saturn, Mercury and Venus appear EVEN CLOSER to each other! In fact, on the 27th and the 28th they appear to be almost one planet! Once again, in order to see this amazing dance of three bright planets, a very good view of the northwestern horizon is necessary from a half-hour to an hour after sunset over the last half of the month of June. Binoculars may help in identifying the planets, but extreme caution must be exercised, so as not to use them before sunset, and risk the great danger of accidentally looking at the sun and suffering eye damage. If they are used, be very sure that it is only after the sun has set. The fifth of the bright plants is reddish Mars, which rises only well after midnight, but it is well up in the east as morning twilight begins. Morning observers will be happy to see that it is now much brighter than it was in the last few months an indication, also, that it will become even brighter in the coming months.

The moon puts on several interesting displays as its monthly orbit carries it around the earth this month. On the evening of June 7, those who have a good northwestern horizon will be able to see the very slim crescent moon just to the right of Venus, if they observe about 45 minutes after sunset. On June 8, at the same time, the slender crescent will be just above Venus, another very beautiful sight! On June 9, the still-thin crescent will be appearing between Saturn and the stars Castor and Pollux. On the evening of June 15, the First Quarter Moon will be very close to planet Jupiter, and very careful observers may notice that the moon moves gradually closer to the planet until the time of their setting at about 1:50 a.m. The next night, on the evening of the 16th, the moon will appear to the left of Jupiter and close to the star Spica, brightest star in the constellation Virgo. On the night of June 28-29, notice that when the Last Quarter Moon rises at about 1:10 a.m., it appears quite close to Mars.

Though the nights of June are short, there is a great deal to see and enjoy, even during twilight! As the great Summer Triangle of stars rises in the east, as the great arm of the Milky Way Galaxy sweeps overhead later in the evening, and as the Great Sagittarius Starcloud, marking the core of our home galaxy, takes its place in the late-night southern sky, ENJOY the vistas! You are encouraged to use a good book with multiple star maps for the whole year to navigate the heavens; a good example of such a book is The Beginners Observing Guide, which is now available at Sharbot Lake Pharmacy.