Friday, August 23
There’s a brief darkish window this night to catch one of the crucial in style galaxies that newbie astronomers love to look at: M51, the Whirlpool Galaxy. Positioned within the small constellation Canes Venatici, which is slowly sinking towards the northwest horizon after darkish, the Whirlpool is a beautiful face-on spiral with a small, compact companion close by.
Canes Venatici sits under the curve of Ursa Main’s tail, a area higher often called the Huge Dipper. When you’ve discovered the Huge Dipper, find the star on the very finish of the deal with, 2nd-magnitude Alkaid (Nu [ν] Ursae Majoris). The Whirlpool lies simply 3.5° southwest of this star, in sparse northeastern Canes Venatici.
As a result of it’s face-on, M51 is fainter than it might be if it have been tilted extra sideways with respect to our line of sight. It glows at magnitude 8.4, with its fuzzy middle extra obvious than the faint, winding arms. Small scopes will definitely decide up that brilliant nucleus, however it could take a while — and a decent-sized scope (8 inches or so) — to identify the arms and make out element. Be certain to set your self up for fulfillment, with an observing website removed from gentle air pollution and by wanting earlier within the night as quickly because it grows darkish, moderately than later, when the area is near the horizon.
M51’s pronounced arms induced astronomer William Parsons, Earl of Rosse, to name it a “spiral nebula” in 1845. Within the two centuries that adopted, many related spiral nebulae have been discovered — which astronomers in the end decided weren’t nebulae in any respect however total galaxies, every just like the Milky Way.
Look additionally for Tenth-magnitude NGC 5195, M51’s small, compact companion, which lies some 4.5′ north of M51’s core. (M51 can be cataloged as NGC 5194.) The smaller galaxy has been caught in an ongoing interplay with M51, which has distorted NGC 5195’s authentic spiral form whereas really enhancing M51’s spiral construction.
Dawn: 6:20 A.M.
Sundown: 7:45 P.M.
Moonrise: 9:56 P.M.
Moonset: 10:59 A.M.
Moon Section: Waning gibbous (79%)
*Instances 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 24
Comet 13P/Olbers, now roughly eighth magnitude, is making its approach by way of Coma Berenices, which lies to the decrease left of Canes Venatici, the constellation we examined final night time. You’ll have a neater time discovering the area by finding the brilliant star Arcturus in Boötes the Herdsman as the big constellation units within the west after sundown. Coma Berenices lies to the decrease proper of this star.
Be prepared to start observing an hour after sundown, as a result of though there’s fairly a while earlier than the Moon rises, there isn’t as lengthy a window earlier than Coma Berenices units. However the effort might be price it — tonight, Olbers is passing lower than 2° northwest of M64, the well-known Blackeye Galaxy.
Yow will discover the pair about 7° southwest of 4th-magnitude Beta (β) Comae Berenices. They are going to seemingly match simply into the sphere of view of a medium-power telescope eyepiece. M64 is a bit fainter than Olbers; the comet has been not too long ago noticed at magnitude 7.7, whereas the galaxy glows at magnitude 8.5. Examine the 2 — Olbers might seem rounder and extra compact than the fuzzy galaxy, which stretches roughly twice so long as it’s huge, some 10′ by 5′.
What gave the Blackeye Galaxy its unusual title? Look first for its brilliant nucleus, then study the encompassing fuzz for a darkish dust lane blotting out a number of the galaxy’s gentle on one facet, which makes half of the galaxy seem a lot fainter than the opposite.
Dawn: 6:21 A.M.
Sundown: 7:43 P.M.
Moonrise: 10:26 A.M.
Moonset: 12:15 P.M.
Moon Section: Waning gibbous (69%)
Sunday, August 25
The Moon passes 4° north of Uranus at 8 P.M. EDT. The pair rise about an hour earlier than native midnight, so are finest noticed within the early-morning sky.
First let’s examine in with them early this morning — say round 4 A.M. native daylight time. The Moon now lies in japanese Aries and is a few 60 % lit. To its decrease left is the Pleiades open cluster, additionally cataloged as M45, in western Taurus. Uranus is a few 5.3° south-southwest of the Pleiades and glows at magnitude 5.8. Particularly with the brilliant Moon close by, you’ll want binoculars or a telescope to find the dim, distant planet. Search for an apparently “flat,” disklike “star” some 4″ throughout, sitting 1° west-southwest of the magnitude 5.7 star 13 Tauri.
By 11:30 P.M. native daylight time this night, the Moon has moved to a place east of the Pleiades and is simply over 50 % lit (it’ll attain Final Quarter phase in just a few hours). The Moon has pulled away to a place northeast of Uranus, standing about 5.5° from the planet at 11:30 P.M. CDT and persevering with to extend the space between itself and the ice giant because the hours progress.
Dawn: 6:21 A.M.
Sundown: 7:42 P.M.
Moonrise: 11:02 P.M.
Moonset: 1:31 P.M.
Moon Section: Waning gibbous (58%)
Monday, August 26
Final Quarter Moon happens this morning at 5:26 A.M. EDT.
An hour and a half earlier, Dwarf planet 1 Ceres reaches its stationary level at 4 A.M. EDT. The largest physique in the primary belt is presently situated in Sagittarius, glowing at magnitude 8.4. You’ll discover it not within the early-morning hours however within the night sky, hanging some 20° excessive within the south round 9 P.M. native daylight time.
The best technique to discover Ceres is to first find Delta (δ) Sagittarii, the Third-magnitude star that marks the place the highest of the Teapot asterism’s spout joins its physique. Ceres is just below 3° southeast of this star, and tonight additionally stands some 1.5° north-northeast of the magnitude 7.6 globular cluster M69.
Dawn: 6:22 A.M.
Sundown: 7:40 P.M.
Moonrise: 11:45 P.M.
Moonset: 2:44 P.M.
Moon Section: Waning crescent (47%)
Tuesday, August 27
The Moon passes 6° north of Jupiter at 9 A.M. EDT this morning. Eleven hours later, our satellite passes 5° north of Mars at 8 P.M. EDT.
Lastly, simply earlier than midnight EDT, at 11 P.M. Jap time, Mercury is stationary in Leo the Lion.
We’ll examine in with the solar system’s smallest planet in just a few days; for now, let’s follow the early-morning sky to observe Jupiter’s largest moon, Ganymede, disappear in an occultation behind the planet.
Like Mars, Jupiter remains to be in Taurus, situated to the decrease left of the Bull’s alpha star, Aldebaran. At magnitude –2.2, Jupiter outshines anything on this area of the sky. Whether or not or not you’ll be able to catch Ganymede disappearing behind the planet’s northern pole depends upon your location — the moon, transferring from west to east, slips behind Jupiter’s northwestern limb simply minutes earlier than 2 A.M. EDT, when the planet is barely 5° excessive within the Midwest and has not but risen farther west. So, solely observers within the japanese half of the U.S. can watch as the big moon slowly disappears behind the planet.
It takes Ganymede virtually precisely two hours to cross behind Jupiter and reappear, beginning round 3:55 A.M. EDT. Now the planet is sort of excessive for observers within the japanese half of the nation and has risen even for these on the West Coast. Like its disappearance, it could take a number of minutes for Ganymede’s massive form to completely emerge from behind Jupiter’s northeastern limb.
The three different Galilean moons are additionally seen: Callisto lies far to the west, with Io nearer to Jupiter, additionally to the west. Europa is alone to the east.
Dawn: 6:23 A.M.
Sundown: 7:39 P.M.
Moonrise: —
Moonset: 3:51 P.M.
Moon Section: Waning crescent (36%)
Wednesday, August 28
The planet Mars stands simply 1.5° northeast of the well-known Crab Nebula this morning. Additionally cataloged as M1, the primary object on Charles Messier’s checklist of “not-comets,” the Crab is a supernova remnant left by an enormous star whose dying throes have been noticed right here on Earth in 1054. The brilliant “new” star lingered within the sky for months, outshining even Venus, and left behind a tangle of fuel and dust that when sat inside and across the progenitor star. On the very middle of the nebula is a pulsar, a quickly spinning neutron star whose poles shoot out beams of radiation that sweep over Earth each time it rotates.
Let’s begin at magnitude 0.8 Mars, which is straightforward to find within the early-morning sky. It’s in Taurus, close to the Third-magnitude star Alheka, which marks the tip of one of many Bull’s two horns. Don’t mistake Mars for brighter, magnitude –2.2 Jupiter, which lies to Mars’ higher proper and is nearer to the brilliant purple large Aldebaran, the Bull’s eye.
When you’ve discovered Mars and Alheka, the Crab varieties the third, westernmost level in a triangle with them. Merely sweep barely southwest of Mars or northwest of Alheka to seek out the small smudge of sunshine that marks the nebula’s place on the sky. It may be fairly faint, so attempt for it earlier within the morning moderately than later, when the sky is darkish however Taurus is effectively above the japanese horizon. Averted imaginative and prescient may help to find it — when you assume you’ve obtained it centered in your eyepiece, attempt wanting off to the facet of the sphere of view to see whether or not it pops out in your peripheral imaginative and prescient.
Dawn: 6:24 A.M.
Sundown: 7:37 P.M.
Moonrise: 12:36 A.M.
Moonset: 4:49 P.M.
Moon Section: Waning crescent (26%)
Thursday, August 29
Lacerta the Lizard is a small, faint constellation — actually, you could not have ever heard of it. However it’s in a chief viewing location this night, hanging within the east above the better-known constellations Andromeda and Pegasus within the hours after sundown.
Lacerta didn’t seem on constellation charts till practically the 18th century, and it homes no brilliant stars or Messier objects. Its alpha star shines at magnitude 3.8 — you’ll discover it 19° under the brighter, well-known star Deneb in Cygnus early this night.
Close to Alpha (α) Lacertae are two of the constellation’s solely deep-sky objects: open clusters NGC 7243 and NGC 7209. Glowing at magnitude 6.4, NGC 7243 spans roughly 21′ and is situated 2.7° west of Alpha Lac. Relying on the dimensions of your scope, you may even see anyplace from 30 to 50 cluster members. On the very middle of the cluster is its brightest star, which shines at magnitude 8.
From NGC 7243, drop simply lower than 4° southwest to land on fainter, magnitude 7.7 NGC 7209. This cluster is barely bigger, spanning about 25′ on the sky and that includes 4 brilliant stars that glow yellow-gold, in distinction to the extra quite a few blue members of the group.
Dawn: 6:25 A.M.
Sundown: 7:36 P.M.
Moonrise: 1:36 A.M.
Moonset: 5:37 P.M.
Moon Section: Waning crescent (18%)
Friday, August 30
Let’s examine in with Mercury because the small planet reaches magnitude 1 within the morning sky, rising a bit of greater than an hour earlier than the Solar.
Some half-hour earlier than dawn, Mercury is 8° excessive within the east, under and a bit of to the left of the slim crescent Moon, which itself hangs beneath the brilliant stars Castor and Pollux in Gemini. These stars — together with just a few different brilliant close by suns reminiscent of Betelgeuse, Rigel, and Sirius — will slowly fade within the rising gentle of the oncoming daybreak.
By way of a telescope, Mercury now spans 9″ — that’s bigger than magnitude 0.8 Mars, far above it in Taurus the Bull. Mercury just isn’t totally lit, however will exhibit a crescent phase simply 22 % illuminated. Examine that to the Moon’s crescent, which is now 12 % lit.
Mercury will rapidly brighten within the coming days, shrinking in total obvious dimension at the same time as its phase grows, reaching half-lit inside per week.
Dawn: 6:26 A.M.
Sundown: 7:34 P.M.
Moonrise: 2:40 A.M.
Moonset: 6:15 P.M.
Moon Section: Waning crescent (11%)
Sky This Week is dropped at you partially by Celestron.
