Saturday, September 5
The
gas giant Jupiter is known for its otherworldly weather. And right now, it’s putting on a show. Every few years, Jupiter experiences outbreaks of brilliant white storms in its Northern Temperate Belt, or NTB. Although the next outbreak wasn’t expected until 2021, it’s happening early — storms burst onto the scene August 18 and were first detected separately by two frequent
Astronomy contributors: Damian Peach and Martin Ratcliffe. It was reported shortly after by Japanese amateur astronomer Isao Miyazaki.
Since then, a second outbreak has occurred, starting early September 2, and more may follow. To catch sight of the storms, you’ll need a telescope with an aperture of 8 inches or larger and a dark, steady sky. Jupiter rotates in just under 10 hours, meaning its features change relatively quickly, even over the course of a single night. Currently, the magnitude –2.5 gas giant is visible in the evenings, already above the southern horizon at sunset and setting around 2 A.M. local time. If you’re an experienced imager, the British Astronomical Association is
requesting images of the storms.
Even if you don’t have a large scope or imaging capabilities, Jupiter — and nearby Saturn, about 8.3° to its east — are great targets within the constellation Sagittarius. The two planets and several of their moons are visible in small scopes and even binoculars, so don’t feel you’re missing out on a great sight without a larger instrument.
Sunrise: 6:32 A.M.
Sunset: 7:24 P.M.
Moonrise: 9:23 P.M.
Moonset: 9:37 A.M.
Moon Phase: Waning gibbous (89%)
Sunday, September 6
The Moon passes 0.03° north of Mars at 1 A.M. EDT. They’re close enough to appear in the same field of view of binoculars and small scopes. You’ll find them together in the southeastern corner of Pisces the Fish. The bright Moon, less than a week past Full, will likely wash out the dim stars of the constellation, but magnitude –1.9 Mars will still be easy to pick out.
For observers in central South America, North Africa, and southern Europe, the Moon and Mars will do more than make a close approach. You’ll see the Moon completely occult, or pass in front of, Mars. Check the
International Occultation Timing Association’s page on the event for occultation times (given in Universal Time, or UT) from the location nearest you. In some places, the occultation will begin and end late on the 5th.
The Moon reaches apogee, the farthest point in its orbit from Earth, at 2:29 A.M. EDT. At that time, our satellite will be 252,032 miles (405,606 kilometers) from Earth.
Sunrise: 6:33 A.M.
Sunset: 7:23 P.M.
Moonrise: 9:48 P.M.
Moonset: 10:35 A.M.
Moon Phase: Waning gibbous (82%)
Monday, September 7
The Moon passes 3° south of Uranus at midnight EDT this morning. You’ll find the pair about 15° above the eastern horizon in Aries the Ram. Uranus is roughly halfway between Aries’ bright star Hamal and Menkar in Cetus. The waning Moon may make it hard to spot the ice giant’s magnitude 5.7 glow, but spend some time in the region with binoculars or your scope, and you may spot the “flat”-looking grayish disk.
Saturn’s two-faced moon Iapetus reaches superior conjunction today. You’ll find the planet and its system of moons — the largest in the solar system — in Sagittarius. Jupiter lies nearby, to Saturn’s west. They’re visible for a few hours after midnight, and again after sunset.
Once you’ve focused in on the planet, look for Iapetus 63" due north of Saturn. The small moon shines at magnitude 11. Because its two hemispheres have vastly different albedos — one is dark, reflecting little light, while the other is brighter and reflects more light — the moon swings between magnitudes 10.5 and 11.7, depending on which hemisphere (or combination of the two) is facing Earth. At superior conjunction, 50 percent of each side is pointed toward us, leaving it roughly in the middle of the two extremes.
With a telescope capable of reaching magnitude 11, you’ll also see several of Saturn’s other moons: Rhea, Tethys, and Dione (all 10th magnitude), as well as magnitude 8 Titan. Once you’ve spotted these small points of light, take some time to admire Saturn’s rings, which extend about 40" from end to end. You may even spot the shadow of the planet falling on the rings’ eastern side.
Sunrise: 6:34 A.M.
Sunset: 7:21 P.M.
Moonrise: 10:14 P.M.
Moonset: 11:34 A.M.
Moon Phase: Waning gibbous (75%)