Starting today, 8th August, this coming week will see a beautiful western sky at twilight. With the waxing crescent moon prominently placed just to the north and east of blue-white Spica and with four of the nine planets visible following sunset, the view promises to be quite spectacular. The view this past evening was a good precursor for the coming week. With mighty Jupiter further east along the ecliptic, elusive Mercury is following the setting sun as Mars and Saturn flank the red supergiant star Antares, forming a pretty, almost-equilateral triangle.
Close to Mars is blue-white Dschubba (delta Scorpii), the crown of the scorpion, the pair making for quite a sight in binoculars (and it was quite striking in binoculars as observed by this author last night). Although Mars has lost its brilliance somewhat compared to its brightness at opposition a few months back in May, its distinctive reddish luster is still quite striking, easily outshining ruddy Antares. Regarding Dschubba, a 400 light-year distant, second-magnitude star, it recently underwent a remarkable change. Back in July 2000, it began to brighten, and during 2001 and 2002 it was closing in on first magnitude, rivaling Antares in brightness. As it turns out, it has a circumstellar disk, produced in part by rapid rotation of at least 181 kms/second, approximately 90 times that of the sun!
Thursday, 4 August, the view toward sunset from the 2.5 kilometer summit of Cerro Las Campanas in the remote Chilean Andes was amazing. Bright but fading Mercury stood very close to a two day old Moon. Both a sunlit lunar crescent and earthlit lunar nightside are captured with the fleeting innermost planet in this breathtaking mountainscape. [Astronomy Picture Of The Day (NASA-APOD) for Sat, 6 August, 2016. Image Credit & Copyright: Yuri Beletsky (Carnegie Las Campanas Observatory, TWAN)].
A pair of binoculars makes for a good viewing companion this coming week. Although the tiny disk of Mercury is only visible in a telescope, scanning east along the ecliptic from the fleet-footed Messenger at mid twilight (approximately 8:30 PM, EDT), brilliant Jupiter quickly comes into view. A keen-eyed observer can spot the giant planet’s four Galilean satellites with binoculars as tiny specks flanking the planet on either side. A careful, steady hand helps and, if you spot them (as I did recently with my 9×63 binoculars), you will note that the plane of their orbits aligns with the plane of the ecliptic – this is one advantage to observing with binoculars, quick eye reference to the sky, the larger, normal-eye view allowing for these comparisons.
While you’re observing Jupiter, keep in mind that in this moment, Juno is in orbit, having arrived on the 4th of July. Although we couldn’t actually ever see it from Earth, even with our most powerful telescopes, the knowledge that it is there, representing us on a mission of discovery and exploration, a view through binoculars, Jupiter appearing very much as it would have appeared to Galileo over 400 years ago, makes your observations that much more meaningful. In a very real sense, this singular act connects you to all of us, to all of humanity, to all the greats of long-past generations who did as you’re doing in this moment, looking up and out towards our collective future and our destiny.
Continuing the easterly scan, the waxing crescent moon comes into view, complete with Earth-shine, the reflected sunlight from the Earth striking the moon. Completing our quick scan of the southwest sky is Saturn, the ringed beauty, furthest to the east. Like the Galilean moons of Jupiter, the rings are visible through 9×63 binoculars to those with a keen eye and a steady hand. Most binoculars are equipped with standard tripod mounting provisions and, to get the best view, use of a tripod is advantageous, especially when sharing the view with family and friends.
Meanwhile, in the east, we have many shades of red, orange and yellow, colors reflected off this lovely bank of cumulus clouds and colors typical of the sky opposite the setting sun or at the very beginnings of twilight.
All our science, measured against reality, is primitive and childlike-and yet it is the most precious thing we have
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