| Observatory |
Some observing hilights
to look forward to...
The following tips on current and upcoming astronomical events
have been gathered from magazines and other sources by Dave Gamble
with the objective of giving OC RASC members a heads-up on
special personal astro-experiences to look forward to.
Sun. July 1 – A harbinger of exciting things to come can be seen just before dawn this morning. As Mars approaches to within a few weeks of its opposition on July 27th the ever brightening red planet will appear just over the width of three fingers from the waning gibbous Moon in the southwest sky.
Sun. July 1 – To bookend a memorable day, there is an opportunity to glimpse the inner planet Mercury early this evening low on the western horizon. Binoculars will help you battle the twilit sky.
Tues. July 3 – The waning gibbous Moon will give us a reminder that the season of the outer planets is arriving. Tonight our neighbour will be about the width of two fingers below the blue ice giant Neptune.
Wed. July 4 – Here is a great challenging opportunity for OCRASC observers! Tonight around 9.10pm, Saturn and its rings will occult a 10th magnitude star in Sagittarius. It will take at least an 8” telescope, but you will be able to see the star wink in and out of the rings and midway it will be blotted out by the northern cusp of the planet’s disk. The whole exercise will take place over the space of about two hours.
Fri. July 6 - If this turns out to be a particularly hot day, a bit of consolation might be drawn from recollecting that Earth is at aphelion, the farthest point in its orbit from the Sun, so it could be worse.
Fri. July 6 – This is Last Quarter Moon night. As well as adding beauty to the early morning hours, the later rising times open up the dark sky period for deep sky observing, imaging and sketching.
Sat. July 7 – Moving along into the early morning sky, the Moon will be close to Uranus tonight. Look for the pale green planet about the width of three fingers above the waning crescent.
Mon. July 9 – Brilliant Venus will have company low in the west this evening as our closest planetary neighbour approaches to within two moon widths of Regulus in Leo. This spring constellation is nearing the conclusion of its 2018 performance and will soon sink into the Sun’s glare, only to reappear in the early morning sky later this year.
Tues. July 10 – A tempting reason to rise early this morning will be the sight of the thin fingernail paring waning crescent Moon in the midst of the Hyades open star cluster. Aldebaran will skim just below the cusp, narrowly avoiding occultation.s
Tues. July 10 – If you have been noticing Jupiter’s westward movement among the stars, tonight it will pause and after this it will creep eastward instead. The previous retrograde motion was due to Earth’s more rapid orbital movement as it passed between Jupiter and the Sun. Nearby tonight will be the bright star alpha Librae, better known as Zubenelgenubi.
Wed. July 11 – Tonight will be as good as it gets for Mercury’s eastern elongation from the Sun, as the inner planet approaches its inward pass between the Earth and the Sun. The swiftly moving planet will soon advance into the Sun’s glare, popping out from the other side to begin its morning appearances in late August. Look for it low near the western horizon after sunset.
Thurs. July 12 – For those with a telescope and adventure in mind, the officially classed dwarf planet Pluto reaches opposition tonight and will be at its peak ‘brightness’ . Finder charts will be needed, and an excellent one can be found on page 48 of the July issue of Sky and Telescope magazine. An interactive one can also be found here: https://in-the-sky.org/findercharts.php?objtxt=A134340&duration=5.
Fri. July 13 – This is New Moon night, opening up all of the still frugal dark sky hours for difficult observing challenges and astro imaging.
Sat. July 14 – For the next two nights the thin crescent Moon will act as a fingerpost to the inner planets. Tonight it will be about the width of one finger above Mercury, low in the western sky after sunset.
Sun. July 15 – This evening the Moon will have a dramatic tryst with brilliant Venus. This is a combination that can be enjoyed with the naked eye, but due to the proximity of the two objects it will be a comfortable fit in binoculars and telescopes as well. Keep an eye out for Regulus in Leo which will be several finger widths further west.
Thurs. July 19 – This is First Quarter Moon night with our neatly divided neighbour gracing the evening hours and complementing the Okanagan summer.
Fri. July 20 – An attractive triangular pattern will be formed in the evening sky tonight as the waxing gibbous Moon joins bright Jupiter and our friend Zubenelgenubi. Though far less bright than its companions, at home 77 light years away, alpha Librae is an interesting double star. One of the companions is itself a very close spectroscopic binary system.
Tues. July 24 – Keeping up its social schedule, tonight the waxing gibbous Moon will visit Saturn which is currently in Sagittarius low in the southern night sky.
Fri. July 27 – Every opposition of Mars is special. The red planet is now placed opposite the Earth from the Sun and takes its place in the sky as a brilliant reddish ‘star’. These looked forward to events happen just over 25 months apart, but because of Mars’ eccentric orbit they are far from equal in brightness. Tonight marks a special one because it occurs near the perihelion point of Mars orbit, producing a generous 24.3 arc second disk, almost as large as it appeared in 2003. Though low in the sky, steady seeing should reveal some exciting surface features in telescopes. It will be many years before another opposition will find it as large and bright as it is this month.
Fri. July 27 – This is Full Moon night with our fully lit neighbour checking out the ripening Okanagan fruit crop. Our neighbour is now at apogee, the farthest point of its orbit from the Earth, and this will be the smallest full moon of 2018, however the difference from average size is slight, and the sheer beauty of the full phase is always outstanding to see.
Mon. July 30 – Though Mars reached opposition directly between the Earth and the Sun on the 27th, tonight it will actually be at its closest point to Earth during this visit. The difference is due to the eccentricity of Mars orbit. For this reason the very closest Mars oppositions occur around late August which is the closest point Mars comes to the Sun.
Mon. July 30 - The Southern Delta Aquarid meteor shower peaks in the early morning hours this morning. Not being one of the more prominent showers, this one will be further compromised by the Full Moon. For those who are still game, look for 'shooting stars' radiating upward from the southern sky in the early morning hours not only on this morning, but for a few days before and after as well.
Tues. July 31 – For those who missed the Moon’s tour guide to Neptune on the 3rd, it will pass just below the blue ice giant again tonight.