Friday, September 13
This Friday the thirteenth, let’s prepare for the upcoming spooky season by searching a ghost — particularly, Mirach’s Ghost.
Mirach is cataloged as Beta (β) Andromedae, whose magnitude 2.1 glow matches that of the Maiden’s alpha star, Alpheratz. It’s situated within the southern portion of the constellation, close to its border with Pisces and Triangulum.
By means of a telescope, Mirach seems noticeably orange, because of its comparatively cool temperature — notably in comparison with Alpheratz, which glows a scorching blue-white. However whenever you take a look at Mirach by means of your telescope, it’s possible you’ll discover an odd, ghostly object lower than 7′ northwest of the star.
This isn’t an inside reflection — it’s a Tenth-magnitude elliptical galaxy some 8,000 light-years away (far past Mirach, which sits simply 200 light-years from Earth). Cataloged as NGC 404, it seems roughly 4’ in diameter from that distance, mendacity simply past the boundary of our Native Group of galaxies. Like Mirach, the Ghost seems an orangey-red shade as properly, on this case as a result of it’s crammed with equally coloured growing older, cool stars.
Dawn: 6:39 A.M.
Sundown: 7:11 P.M.
Moonrise: 4:53 P.M.
Moonset: 12:51 A.M.
Moon Section: Waxing gibbous (75%)
*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, September 14
Tonight is Worldwide Observe the Moon Evening, with celebrations throughout the globe highlighting Earth’s pure satellite tv for pc. You possibly can go to NASA’s web page for the occasion to discover a gathering close to you, or just step outdoors by yourself this night to get pleasure from a take a look at our waxing gibbous Moon, now only a few days from Full — and an upcoming lunar occultation and eclipse, so keep tuned for extra particulars later this week.
In fact, Earth is much from the one planet with a pure satellite tv for pc, and in a single day tonight, one in every of Jupiter’s 4 massive moons (also referred to as the Galilean moons) is transiting in entrance of its disk. Yow will discover Jupiter within the constellation Taurus; the planet seems above the jap horizon starting round 11 P.M. native daylight time, to the decrease left of the Bull’s shiny crimson eye, Aldebaran. At magnitude –2.3, the planet far outshines the 1st-magnitude crimson large.
Lower than quarter-hour after midnight within the Midwest (1 A.M. EDT on the fifteenth), Io’s shadow seems on the planet’s southeastern limb. Io itself is about 20” behind it, farther east. Each shadow and moon are shifting westward, with Io crossing onto the disk round 2:30 A.M. EDT (once more on the fifteenth, however late on the 14th for these on the West Coast). The shadow continues throughout, leaving the disk round 3:20 A.M. EDT, with Io following at 3:41 A.M. EDT.
Additionally seen right now are Europa farther to Jupiter’s east, in addition to Ganymede and Callisto to the planet’s west, with the previous sitting nearer to the gasoline large than the latter.
Dawn: 6:40 A.M.
Sundown: 7:09 P.M.
Moonrise: 5:34 P.M.
Moonset: 2:03 A.M.
Moon Section: Waxing gibbous (84%)
Sunday, September 15
Let’s flip again to the Moon tonight to give attention to an space close to its western limb as daylight makes its approach throughout the floor. That daylight has now reached the southwestern fringe of Oceanus Procellarum, the Ocean of Storms, one of many largest of the Moon’s darkish maria.
Alongside that southwestern rim, look with a telescope for a easy, spherical, dark-floored crater — that’s Billy. Its ground consists of basaltic lava, which is what makes it so darkish. To Billy’s northwest is a pointy, straight valley known as Rimae Sirsalis, which seems to chop instantly by means of the terrain because it shoots away from Oceanus Procellarum’s rim. The rille stretches for some 205 miles (330 kilometers). Even farther northwest is the double crater Damoiseau M.
This complete area is lit with lengthy shadows, providing wonderful distinction this night. By tomorrow evening, that may have modified, because the Solar strikes overhead within the lunar sky and the shadows shorten, making it tougher to intently study the rugged terrain.
Dawn: 6:41 A.M.
Sundown: 7:08 P.M.
Moonrise: 6:07 P.M.
Moonset: 3:20 A.M.
Moon Section: Waxing gibbous (92%)
Monday, September 16
Rising larger within the northeast in the course of the early hours of the morning, the constellation Lynx holds our goal in the present day. We’re in search of 10 Ursae Majoris — however don’t let the title idiot you, as a result of this star sits squarely inside the boundaries of the Lynx (not less than, as of late).
Additionally cataloged as HR 3579 Lyncis, this 4th-magnitude star sits about 8.5° northwest of Lynx’s Third-magnitude alpha star. Alternatively, you possibly can drop 5.5° due south of 4th-magnitude Kappa (κ) Uma to seek out it as properly.
10 Uma is a double star with elements that shine at 4th and sixth magnitude. They’re each barely extra large than the Solar and orbit one another each 22 years, showing simply ½” aside on the sky. That’s too shut to separate visually, however they are often tracked by finding out the sunshine from the seemingly singular star for shifts towards the crimson or blue finish of the spectrum because the elements orbit, known as Doppler shifts.
When you’re in search of a binary pair you can cut up, slide your gaze north into Ursa Main correct, to the binary system Struve 1321, some 3° west of Theta (θ) Uma. This method incorporates two crimson dwarf stars, each eighth magnitude, which might be simply cut up utilizing an 8-inch scope with a magnification of 100x, or larger magnification on a smaller scope. Each stars ought to seem an orangey-yellow shade.
Dawn: 6:42 A.M.
Sundown: 7:06 P.M.
Moonrise: 6:36 P.M.
Moonset: 4:39 A.M.
Moon Section: Waxing gibbous (97%)
Tuesday, September 17
At the moment the Moon really takes middle stage, starting early within the morning when the almost Full Moon occults (passes in entrance of) the planet Saturn in Aquarius for observers within the western U.S. (together with Hawaii) and Canada.
The occasion begins round 5 A.M. MDT, when the Moon and Saturn are simply 10° excessive within the west within the Mountain time zone and 10° larger for these on the West Coast (and it’s an hour earlier, 4 A.M. PDT). Zoom in on Saturn with a telescope to look at the planet slowly slip behind the vanguard of the Moon over the course of roughly half a minute. Be aware that as a result of the Moon is so shiny, the planet and notably its rings will seem fairly faint. The Worldwide Occultation Timing Affiliation’s web site lists the timing from numerous cities, because the second Saturn will disappear is closely dependent in your location.
These within the jap half of the U.S. and Canada received’t see the occultation, however you possibly can nonetheless watch the Moon closing in on Saturn because the pair units within the west shortly earlier than dawn. There, the Moon passes 0.3° due north of Saturn at 6 A.M. EDT.
However the Moon isn’t carried out dazzling us but. Full Moon happens at 10:34 P.M. EDT, bringing us the September Corn Moon. However this Full Moon has a lot extra in retailer: It’s additionally the Harvest Moon, the title given to the Full Moon that happens closest to the autumnal equinox (which is subsequent week, on the twenty second). Plus, it’s a Tremendous Moon, the title for a Full Moon that happens across the similar time as when our satellite tv for pc reaches the closest level to Earth in its barely elliptical orbit — a place often known as perigee, which the Moon will hit tomorrow morning.
And at last, this Full Moon additionally precedes the upcoming annular photo voltaic eclipse October 2, bringing us a partial lunar eclipse because the celestial geometry will get lined up.
The eclipse begins at 8:41 P.M. EDT, which is shortly after the Moon rises for these within the Midwest. As first umbral contact approaches at 10:12 P.M. EDT, take a look at our satellite tv for pc’s northern limb to see whether or not you discover it beginning to flip a bit duskier because the eclipse progresses. At most eclipse (occurring at 10:45 P.M. EDT), simply 8 p.c of the Moon shall be lined, however it would final for simply over an hour. The eclipse then continues in reverse, with the northern limb of the Moon rising slowly brighter till the occasion ends at 12:47 A.M. EDT (on the 18th for these within the Jap time zone solely).
Dawn: 6:43 A.M.
Sundown: 7:04 P.M.
Moonrise: 7:03 P.M.
Moonset: 5:58 A.M.
Moon Section: Full
Wednesday, September 18
The Full Tremendous Moon passes 0.7° north of Neptune at 4 A.M. EDT. When you’re nonetheless up after watching the eclipse, search for the pair because the area units within the west as sundown approaches. Regardless of the Moon’s shiny gentle, you would possibly nonetheless be capable of spot the celebs of Pisces’ Circlet asterism, with the Moon standing some 5° to the left of Lambda (λ) Piscium, the southeasternmost star within the group.
Neptune would require a telescope to identify, additionally 5° from Lambda, to that star’s southeast. When you can, wait so long as potential for the Moon to tug farther away from the planet to keep away from dropping its faint, tiny disk among the many glare. Distant Neptune glows at magnitude 7.7 and its disk stretches simply 2” throughout; the ice large will attain opposition in simply two days’ time, so we’ll actually return to it after the Moon has moved away only a bit and we are able to catch the blue-hued world at its greatest.
Nonetheless totally illuminated, the Moon reaches perigee, the closest level to Earth in its orbit, at 9:22 A.M., when it stands some 227,007 miles (365,332 km) away. This month’s Tremendous Moon is the second of 4 such Tremendous Moons this 12 months, beginning with the August Full Moon final month and ending with November’s.
Dawn: 6:44 A.M.
Sundown: 7:03 P.M.
Moonrise: 7:28 P.M.
Moonset: 7:16 A.M.
Moon Section: Waning gibbous (99%)
Thursday, September 19
Mercury reached a wonderful apparition earlier this month; now it’s shortly “falling” out of sight, its distance from the Solar shrinking daily because it heads for superior conjunction on the finish of September.
Though it has been brightening — the planet now shines at magnitude –1.3 — Mercury can also be rising later every morning. At the moment it reaches an altitude of simply 3° above the horizon half an hour earlier than dawn, which means observers ought to take care to set an alarm for a number of minutes earlier than dawn from their location, which can differ from the instances given under.
You’ll doubtless want binoculars to identify it in any respect within the rising twilight. By means of a telescope, the innermost planet’s disk spans 5″ and is sort of totally illuminated, with some 93 p.c of its floor in daylight.
As twilight grows, see how lengthy you possibly can observe a couple of of the opposite shiny factors of sunshine within the sky: Blazing Jupiter in Taurus now acts as a morning star excessive within the south, whereas the brilliant stars Sirius in Canis Main and Procyon in Canis Minor might also stay seen, hanging under the planet within the southeast.
Dawn: 6:45 A.M.
Sundown: 7:01 P.M.
Moonrise: 7:55 P.M.
Moonset: 8:34 A.M.
Moon Section: Waning gibbous (96%)
Friday, September 20
The distant planet Neptune reaches opposition tonight at 8 P.M. EDT. Situated in Pisces, you’ll discover it hanging under magnitude 4.5 Lambda Psc because the constellation rises within the east this night. The Moon has now moved to Aries; our satellite tv for pc remains to be shiny however there’s a brief darkish window after sundown to search for Neptune in a moonless sky.
An hour after sundown, Neptune is 10° excessive and lies 5° southeast of Lambda Psc. Now some 2.7 billion miles (4.3 billion km) from Earth, it glows at magnitude 7.7 and requires binoculars or a telescope to select up. The planet’s disk will seem as a spherical, “flat” star among the many background pinpricks of sunshine, spanning simply 2” throughout. Chances are you’ll discover the disk’s distinctive bluish hue.
Don’t mistake close by Saturn for Neptune — the latter is in Pisces and never seen to the bare eye, whereas the previous, in Aquarius, glows at magnitude 0.6 and is seen with out optical assist.
Dawn: 6:46 A.M.
Sundown: 6:59 P.M.
Moonrise: 8:24 P.M.
Moonset: 9:53 A.M.
Moon Section: Waning gibbous (90%)
Sky This Week is delivered to you partly by Celestron.
