: This Southern Hemisphere shot exhibits the regal constellation Scorpius totally above the horizon. The Moon will go to this constellation this week, passing close to its vivid purple big “coronary heart,” Antares. Credit score: Luis Argerich (Flickr)
Friday, August 18
Comet C/2023 E1 (ATLAS) is making its closest strategy to Earth as we speak, now simply 3 light-minutes away. That interprets to a distance of about 33.5 million miles (54 million kilometers), rendering the comet a comparatively vivid tenth magnitude, a prepared goal for telescopes.
You’ll discover ATLAS in japanese Cygnus, proper close to the Swan’s border with the constellation Pegasus. It’s now about 16.5° southeast of vivid Deneb and 13.5° southeast of the well-known North America Nebula (NGC 7000). The comet additionally lies slightly below 1.5° southeast of the deep purple, Sixth-magnitude carbon star V460 Cygni, providing an awesome composition for astrophotos.
ATLAS is seen all through the night hours, rising increased by way of about 1 A.M. native daylight time and setting after the Solar tomorrow morning. Should you haven’t managed to set your sights on this icy customer from the outer solar system, now could be the time. ATLAS is now previous perihelion (its closest level to the Solar) and is headed again out previous Earth into the distant solar system, so it would proceed to fade because the weeks go by. It gained’t return for some 85 years.
Different occasions that happen as we speak embody the fragile crescent Moon passing 1.1° north of asteroid 2 Pallas in addition to 7° north of Mercury at 7 A.M. EDT. The Moon will even cross 2° north of Mars at 7 P.M. EDT — you possibly can catch a glimpse of the pair setting within the west shortly after sundown, earlier than the sky is darkish sufficient to start searching down ATLAS.
Dawn: 6:14 A.M.
Sundown: 7:53 P.M.
Moonrise: 8:13 A.M.
Moonset: 9:12 P.M.
Moon Section: Waxing crescent (5%)
*Occasions for dawn, sundown, moonrise, and moonset are given in native time from 40° N 90° W. The Moon’s illumination is given at 12 P.M. native time from the identical location.
Saturday, August 19
Jupiter floats close to the Fifth-magnitude star Sigma (σ) Arietis for the remainder of the month. This morning, you possibly can catch the star masquerading as a Galilean moon!
Jupiter rises shortly earlier than native midnight, so the very best time to catch it’s within the few hours forward of dawn, when it’s increased within the sky. However as we speak, you’ll wish to begin observing as early as doable, as a number of occasions happen between midnight and daybreak. Let’s begin round 1 A.M. EDT, when Jupiter is flanked by two moons on all sides. To the west lie Europa (closest) and Ganymede, whereas to the east are Io (closest) and Callisto.
In truth, Callisto sits some 10′ east of Jupiter… however there are two vivid factors of sunshine in that area. Which is the moon? It’s the fainter level simply farther out; about 2′ nearer to the planet is Sigma Ari. The star is definitely extra in step with the opposite three moons than Callisto, which lies barely north of that aircraft.
Maintain watching and also you’ll see Io closing in on the gas giant’s japanese limb. Minutes after 1 A.M. EDT, Io’s shadow seems on the cloud tops; the moon follows in a transit that begins greater than an hour later, simply after 4:20 A.M. EDT. The shadow is greater than midway throughout by then, leaving the disk round 5:10 A.M. EDT (as twilight is simply starting on the East Coast). Io continues its journey, lastly ending its transit round 5:30 A.M. CDT, after dawn within the Jap time zone.
Dawn: 6:15 A.M.
Sundown: 7:51 P.M.
Moonrise: 9:13 A.M.
Moonset: 9:32 P.M.
Moon Section: Waxing crescent (10%)
Sunday, August 20
The globular cluster M15 lies in far western Pegasus, about 4° northwest of 2nd-magnitude Enif (Epsilon [ε] Pegasi), which marks the Winged Horse’s nostril. At magnitude 6.3, the cluster can simply be noticed with the bare eye below darkish circumstances, and it’s already 45° above the japanese horizon some two hours after sundown tonight.
Even a comparatively small scope (4 inches) can start to resolve a number of the stars round this historical cluster’s vivid, compact core. Observers typically word obvious chains of brighter, easy-to-pick-out stars that spiral out from the middle, giving the cluster a barely rectangular look. And, for those who’re an avid astrophotographer or have a big (12 to fifteen inches or extra) scope, there’s one thing significantly particular about M15 you could view: the planetary nebula Pease 1. This bubble of gasoline, blown off by its getting older dad or mum star, is simply offset from the cluster’s heart. You’ll want magnification of 300x or extra, and an OIII filter will additional assist convey out the gasoline’ dim glow. Though it’s robust to identify, Pease 1 was the primary planetary nebula found in a globular cluster — and researchers do consider it’s related to the cluster, quite than an opportunity superposition.
Even when this problem is just too nice, M15 continues to be a surprising goal price having fun with. Plus, there are different related sights within the sky — in one other few months, we’ll strive for the planetary nebula NGC 2438, which sits in entrance of an open cluster (M46) within the wintertime sky.
Dawn: 6:16 A.M.
Sundown: 7:50 P.M.
Moonrise: 10:12 A.M.
Moonset: 9:52 P.M.
Moon Section: Waxing crescent (16%)
Monday, August 21
After passing by way of inferior conjunction simply over every week in the past, Venus is again! The intense planet now seems within the morning sky earlier than dawn, so it’s nice for early risers.
At magnitude –4.1, the world is straightforward to identify, supplied you will have a transparent japanese horizon. It’s almost 4° excessive in Most cancers the Crab about half an hour earlier than dawn and climbing. As a result of it’s so vivid, the planet ought to stay seen even within the rising twilight. Should you do choose to view it with binoculars or a telescope, ensure to place them away a minimum of a number of minutes earlier than dawn out of your location (which can differ barely from the time given beneath).
By means of these optics, Venus stretches a powerful 56″ throughout. It at present simply 0.3 astronomical unit away, or lower than 28 million miles (45 million km). (1 astronomical unit, or AU, is the common Earth-Solar distance.) Its phase is a mere 3 %, providing solely a sliver of sunlit clouds on view. Throughout the remainder of August, Venus will rise earlier and its phase will wax, reaching 11 % lit by the top of the month. On the similar time, its dimension will barely diminish, shrinking 6″ by the thirty first.
Dawn: 6:17 A.M.
Sundown: 7:49 P.M.
Moonrise: 11:14 A.M.
Moonset: 10:14 P.M.
Moon Section: Waxing crescent (24%)
Tuesday, August 22
The constellation Vulpecula the Fox lies simply south of Cygnus and Lyra within the northern sky. It’s a area rife with deep-sky targets, together with the one we’re exploring tonight: Collinder 399, also referred to as the Coathanger.
That is a straightforward binocular or small scope object, so it’s nice for starting observers. You’ll discover this asterism, or unofficial sample of stars, throughout the Summer season Triangle bounded by the intense stars Deneb, Vega, and Altair. The final of those three, positioned in Aquila the Eagle, is our jumping-off level: Look about 13°, or two binocular fields, northeast of this star to search out the Coathanger’s distinct form.
Additionally referred to as Brocchi’s Cluster, the Coathanger shines collectively at magnitude 3.6, with 10 of its stars brighter than magnitude 7. The complete group spans about 1°, or two Full Moons, so it’s quite giant. Its bar is product of six stars in a comparatively straight line, whereas the hook sprouts southward from the center as a curve of 4 extra stars.
Dawn: 6:18 A.M.
Sundown: 7:47 P.M.
Moonrise: 12:18 P.M.
Moonset: 10:39 P.M.
Moon Section: Waxing crescent (33%)
Wednesday, August 23
Mercury has been making its method quickly east by way of southern Leo within the night sky. As we speak, although, the solar system’s smallest planet stands stationary at 1 A.M. EDT. It would now start shifting westward, or retrograde, towards the background stars, heading again towards magnitude 1.4 Regulus, additionally referred to as Cor Leonis or the Lion’s Coronary heart.
Mercury is getting arduous to identify, now magnitude 1 and simply 1.5° above the horizon a mere 20 minutes after sundown. You should still be capable of sight it by way of a telescope and even binoculars, however it will likely be a problem towards the still-bright sky. Should you’re capable of catch its 10″-wide disk, you need to discover that it reveals a crescent phase some 23 % lit.
Simpler to look at will likely be Mars, some 7.5° to Mercury’s east (higher left) — the Pink Planet is fainter at magnitude 1.8 however will stay within the sky longer as darkness falls, giving its gentle time to seem earlier than it sinks too low. Mars is positioned in Virgo, sitting about ¼° due east of 4th-magnitude Beta (β) Virginis. Far to the pair’s east is the Maiden’s barely brighter Third-magnitude gamma star, the attractive binary system Porrima — actually price observing this night as nicely!
Dawn: 6:19 A.M.
Sundown: 7:46 P.M.
Moonrise: 1:26 P.M.
Moonset: 11:10 P.M.
Moon Section: Waxing crescent (43%)
Thursday, August 24
First Quarter Moon happens at 5:57 A.M. EDT, bringing half of Luna’s face into daylight as our satellite rises within the daytime sky. An hour after sundown, as the celebs are starting to seem, the Moon hangs within the south amid the celebs of Scorpius, inside 1° northwest of the arachnid’s vivid purple coronary heart.
For many of the world, the Moon will cross 1.1° due north of Antares at 10 P.M. EDT. However many observers within the U.S. and Canada will as a substitute see the Moon utterly blot out the star because it passes in entrance of it from our perspective in an occultation this night. You’ll be able to verify whether or not the occasion is seen out of your location on the Worldwide Occultation Timing Affiliation’s page for the event, which lists the instances of Antares’ disappearance and reappearance from most main cities within the path.
Whilst you’re ready for the occasion to start, you should utilize a telescope to check the rugged lunar floor, significantly alongside the terminator dividing evening and day. That is the place the distinction is biggest and options within the panorama stand out within the biggest element. However below this Solar angle, some acquainted options may also look alien — just like the crater Tycho, normally recognized for its lengthy, light-colored rays that sweep upward from the south. Tonight, Tycho will likely be a lot more durable to search out, these rays all however invisible. As a substitute, search for close by Clavius, well-known for the small arc of craterlets inside its partitions. As soon as you discover Clavius, it’s a brief jaunt north to Tycho — take a look at our map above and see if you will discover it!
Dawn: 6:20 A.M.
Sundown: 7:44 P.M.
Moonrise: 2:35 P.M.
Moonset: 11:48 P.M.
Moon Section: Waxing gibbous (53%)
Friday, August 25
Saturn is now two days from opposition, providing its greatest views for the yr. The ringed planet lies in Aquarius, shining at magnitude 0.4 and making a vivid level of sunshine within the in any other case sparse central areas of the constellation. Two hours after sundown, Saturn is already 20° excessive within the southeast and persevering with to climb. Your greatest views will come late within the night and early into tomorrow morning, because it rises far above the turbulent air close to the horizon (and any gentle air pollution you might need there as nicely).
By means of a telescope, Saturn is surrounded by its broad ring system. That’s the place we’re concentrating our effort tonight and over the following few days, because the rings bear a phenomenon referred to as the Seeliger impact. This causes the rings to apparently brighten within the few days round opposition, because the Solar strikes straight behind Earth as we view Saturn and any shadows solid by ice particles on the rings disappear. To watch the impact, you’ll wish to take a peek at Saturn each day for the following week or so — the impact is biggest at opposition, so it needs to be ramping up now; then, the rings will start to darken barely within the days following the twenty seventh. Making a sketch or taking a picture every evening might help you chart the impact.
You may additionally be capable of simply spot Saturn’s largest moon, Titan, now standing 2.5′ due east of the planet. It would stay east of Saturn by way of opposition, even because the planet’s fainter, closer-in moons orbit way more rapidly, present process transits and occultations. Tethys will transit Saturn’s southern polar area beginning round 1:45 A.M. EDT tomorrow morning (the twenty sixth for observers within the Jap and Central time zones, however nonetheless Friday evening for these within the western half of the U.S.). As a result of the planet is so near opposition, the moon and its shadow seem to cross at almost the identical time — Tethys’ shadow simply barely leads and could also be indistinguishable from the moon itself in lots of scopes.
Dawn: 6:21 A.M.
Sundown: 7:43 P.M.
Moonrise: 3:45 P.M.
Moonset: —
Moon Section: Waxing gibbous (64%)
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