For a short time this month, Taurus will seem to have two eyes as Mars (higher left) strikes northwest of Aldebaran (beneath heart), as on this 2023 photograph. Comet C/2022 E3 (ZTF) can also be seen right here, to Aldebaran’s decrease left. Credit score: Alan Dyer
The planets are spreading out this month. Mercury and Venus lie within the night sky; after midnight the following set of planets rises one after the opposite, led by Saturn. It’s adopted into the early-morning sky by Neptune, Mars, Uranus, and Jupiter. Saturn particularly is gorgeous, with the rings at their narrowest for the yr.
First to set after the Solar on July 1 is Venus. It’s a difficult object to seek out, disappearing inside half-hour of sundown. When you’ve got a really clear western horizon, search for the magnitude –3.9 planet in shiny twilight, standing solely 2° excessive quarter-hour after sundown.
Attempt once more on July 6, when the crescent Moon seems 7° excessive about 20 minutes after sundown. Venus lies 5° beneath it and as soon as once more units shortly.
By the tip of July, Venus is sort of 16° east of the Solar however nonetheless hugs the horizon from northern temperate latitudes. It stands 3° excessive half-hour after sundown, and people scanning the horizon with binoculars would possibly spot 1st-magnitude Regulus, Leo’s brightest star, 5° east of the planet. Mercury can also be current, on the similar altitude as Venus and 4.7° south of Regulus, shining at magnitude 0.9.
Rewinding a bit, Mercury shines within the night sky at magnitude –0.6 on July 1. A wholesome 18.5° from the Solar, it stays 7° excessive half-hour after sundown. Because the sky darkens, Mercury will likely be a simple object to catch. Look ahead to Castor and Pollux, Gemini’s pair of 1st-magnitude stars, which stand on the similar altitude above the horizon northwest of Mercury.
Mercury slides away from the pair of stars shortly and by July 7, the waxing Moon stands 3° above Mercury — an attractive sight in twilight. Search for earthshine illuminating the darkish hemisphere of the Moon.
Mercury fades because it will increase its distance from the Solar and reaches its biggest jap elongation of 27° on July 22. It has now dimmed to magnitude 0.5 and stands inside 3° of Regulus. The planet has change into tougher to seek out. Mercury stands 5° excessive 40 minutes after sundown, a great time to identify it.
As a result of low angle of the ecliptic to the horizon within the Northern Hemisphere, this isn’t as favorable as elongations that happen in March. Southern Hemisphere observers could have a greater view.
Saturn rises at midnight on July 1, situated in northeastern Aquarius simply 2.1° from Phi (ϕ) Aquarii. It’s straightforward to identify at magnitude 0.9. The ringed world barely strikes at first, then slowly progresses alongside its retrograde path and ends the month inside 1.5° of Phi.
On July 24, a waxing gibbous Moon stands about 7° west of Saturn. Later within the day for areas in Africa, Asia, and Indonesia, the Moon occults Saturn. The planet brightens to magnitude 0.7 by the tip of July in preparation for September’s opposition.
The rings seem very high-quality and practically edge-on via a telescope, tilted by solely 2° to our line of sight. Its disk spans 18″ and the huge axis of the rings stretches roughly 41″ throughout. By way of the tip of the yr, the rings will widen earlier than closing once more and showing edge-on in March 2025.
Now that the ring airplane is nearly edge-on, Saturn’s satellites cross in entrance of or behind the planet. Titan, the brightest moon at magnitude 8.5, orbits each 16 days. The moon is occulted by Saturn July 8 round 2:40 a.m. EDT (not seen within the Pacific time zone). It takes a number of minutes to vanish, so start watching 10 to twenty minutes earlier. A second occultation happens July 24 round 1:30 a.m. EDT (not seen in Mountain or Pacific time zones).
On July 16, Titan begins a transit throughout Saturn simply earlier than 2:30 a.m. EDT (once more, not seen on the West Coast). The transit lasts practically 4 hours, with egress occurring round 4:20 a.m. MDT (in daylight for the East Coast and practically dawn within the Midwest).
The transit beginning July 31/Aug. 1 at 1:15 a.m. EDT is the primary simply seen from the Mountain time zone, though Saturn is at an elevation of solely 13°.
Dione begins a transit an hour later, led by its shadow, which seems behind Titan on the cloud tops — a rare alignment. Dione is a small moon that shines at Tenth magnitude, so it’s troublesome to see in opposition to the intense background of Saturn. It’s simpler to seize utilizing high-speed video and image-refining methods.
A number of moons additionally skim the sting of the rings as seen from Earth, though these are additionally troublesome to watch. Once more, high-resolution imaging can catch these occasions.
Iapetus orbits at a a lot larger distance from Saturn each 79 days. It strikes 1′ north of Saturn on July 6, reaching inferior conjunction because it heads towards western elongation on the twenty seventh. Between early July and this date, Iapetus brightens from about eleventh magnitude to magnitude 10.2.
Neptune is in southwestern Pisces, some 5° southeast of Lambda (λ) Piscium within the Circlet. It rises round midnight and reaches a great top within the jap sky by 2 a.m. native daylight time. As you scan with binoculars, search for a parallelogram of 4th- to Fifth-magnitude stars. The northernmost shiny one is 29 Psc; a lot dimmer Neptune lies practically 2° to its north. Neptune shines at magnitude 7.7.
On July 25, the waning gibbous Moon stands about 4.5° southwest of Neptune two hours after rising. By daybreak they’re lower than 3° aside. Neptune reaches its stationary level early in July and the planet barely strikes all month.
The following planet up is Mars, rising simply after 2 a.m. native daylight time on July 1 with a waning crescent Moon. The Purple Planet shines at magnitude 1 in southeastern Aries, 15° from the Pleiades (M45). Mars strikes into Taurus by July 12.
Mars is closing in on Uranus, additionally in western Taurus, they usually’re simply over 2° aside on the twelfth. Look once more on July 15, when Mars and Uranus stand solely 0.6° aside. Binoculars will reveal the dim, greenish-blue-hued disk of Uranus due north of Mars. Uranus shines at magnitude 5.8. The pair now stand 6° southwest of the Pleiades. Examine every consecutive night time as Mars pulls away from Uranus, transferring about 0.7° east per day.
On July 20, Mars stands 4.8° due south of M45. By the twenty second, it’s brightened to magnitude 0.9. Mars continues eastward and on the finish of July stands 5.5° northwest of Aldebaran, matching the star in magnitude. For a time, Taurus the Bull seems to have two eyes. A waning crescent Moon joins Mars a day earlier, on July 30. Together with M45 and Jupiter, additionally in Taurus, the view is spectacular.
By way of a telescope, Mars is a difficult 6″ throughout and stands 30° excessive within the east as twilight begins on July 31.
Uranus stays close to the western fringe of Taurus all month. Its disk spans solely 3″ via a telescope, difficult to see until circumstances are glorious. As soon as Mars has left the scene, you may spot Uranus in binoculars 2° west of a pair of Sixth-magnitude stars, 13 and 14 Tauri, that are lower than 0.4° aside and about 4.5° due south of the Pleiades.
Jupiter’s visibility improves every day because it climbs increased within the pre-dawn sky. The gas giant rises round 3:30 a.m. native daylight time on July 1, north of the Hyades star cluster in Taurus. A waning crescent Moon joins it July 3. By the thirteenth, Jupiter stands 5° due north of Aldebaran. The crescent Moon once more joins Jupiter July 30 and 31. The planet begins the month at magnitude –2 and brightens by 0.1 magnitude by July 31, now rising earlier than 2 a.m.
By way of a telescope, Jupiter spans 35″ and is joined by the 4 Galilean moons, Io, Europa, Ganymede, and Callisto. Catching a transit or occultation is a good way to begin a summer season morning.
Early on July 4, Ganymede transits Jupiter’s south polar area. The occasion is underway as Jupiter rises within the western U.S. Ganymede slowly exits the disk round 5:50 a.m. MDT in twilight, whereas it’s nonetheless darkish within the Pacific time zone.
Io and Europa placed on a pair of occasions the morning of July 6. Europa’s transit begins at 4:42 a.m. EDT, seen from the jap U.S. The moon’s shadow is already practically accomplished with a transit, approaching the western limb. As Jupiter rises farther west, Io’s shadow begins to transit at 5:15 a.m. CDT, as twilight encroaches on the Midwest. Observers within the western U.S. will see Io start its transit at 5:02 a.m. MDT, with Europa exiting the disk minutes later, round 5:12 a.m. MDT.
Ganymede’s enormous shadow crosses Jupiter’s south polar area July 11 between 4:52 a.m. and 6:40 a.m. MDT. (The exit happens in daylight for the Mountain time zone however twilight within the Pacific time zone.) Europa’s shadow crosses the disk July 13, beginning round 5:15 a.m. EDT, as Europa closes on Jupiter’s jap limb and begins its personal transit round 5:30 a.m. MDT.
Probably the most fascinating occasions of the month is the transit of Io with its shadow as Ganymede reappears from eclipse on July 22. The primary pair of occasions is healthier noticed throughout the jap half of the U.S. Io’s shadow begins a transit at 4:31 a.m. EDT (when Jupiter is just 10° excessive within the Midwest). Ganymede is occulted by Jupiter’s northwestern limb seven minutes later. In the meantime, Io is approaching the jap limb and begins to transit at 5:31 a.m. EDT. Ganymede passes behind Jupiter and reappears round 4:36 a.m. MDT, in shiny twilight for the Midwest.
One other set of occasions happens July 29. Ganymede enters Jupiter’s prolonged shadow west of the planet simply earlier than 4:40 a.m. EDT, adopted by Europa simply over an hour later, shortly earlier than dawn within the Japanese time zone. Then, Io’s shadow begins a transit on the jap limb at 5:25 a.m. CDT. Inside minutes, Ganymede exits the shadow nonetheless northwest of Jupiter at 5:28 a.m. CDT, a course of that takes a couple of minutes. Watch it brighten as Io’s shadow strikes onto the cloud tops. Io itself begins to transit round 5:30 a.m. MDT, now in shiny twilight throughout the Mountain time zone however effectively seen in Pacific states.
Rising Moon: Rack up the balls
A lazy, hazy summer season night time is the right time to loosen up your scientific gaze and let your thoughts wander, your eyes meandering slowly alongside the day-night lunar zone we name the terminator. You’ll have seen the extra well-known Lunar X or V, examples of a clair-obscur impact — when the play of sunshine and shadow call to mind a letter, quantity, animal, face, or different object. However will you see a rack of pool balls July sixteenth, simply west of the crater Delisle?
In actuality, this can be a clump of peaks left over from the large affect that carved out Mare Imbrium, towering above the plains of lava that welled up afterward. But our earthbound brains crave familiarity in a international land. A few hours later, one other area west of Mons Gruithuisen Gamma suggests an upturned sink or bathtub to some observers.
If this pareidolia tickles your fancy, do a seek for “Moon clair-obscur lunarism” to seek out dozens of blogs and movies with dates and instances that concentrate on these options. Mike Rowles has compiled a listing of 99 such lunarisms — some you may see two nights in a row, others fleetingly for an hour or two. Relive that childhood enjoyment of seeing shapes in clouds.
Meteor Watch: A broad peak
July begins quietly on the meteor bathe entrance, with charges growing towards the tip of the month because the early Perseids start and the Southern Delta Aquariid bathe reaches its peak. The latter is lively from July 12 via Aug. 23 and peaks on July 31, though exercise is pretty broad throughout a couple of days on both aspect of this date.
The radiant is close to the star Skat in Aquarius, which reaches 30° elevation round 3 a.m. native daylight time, leading to noticed charges of about half the expected zenithal hourly fee of 25 meteors per hour. The waning crescent Moon could have some impact on the visibility of fainter meteors.
The Southern Delta Aquariids are the results of Comet 96P/Machholz. That is 1 of 8 showers associated to the comet, which has a 5.3-year orbital interval.
Comet Search: In your mark, get set, go!
The very best two comets of the night time are sinking beneath 15° altitude by sundown, so be on the right track as darkness arrives. Head straight south of Leo’s tail to get to C/2023 A3 (Tsuchinshan-ATLAS). On observe to blow our socks off in October, it at the moment glows at a modest Eighth magnitude and may sport a faint eastward tail if skies are darkish and clear sufficient. Approaching Mars’ orbit, the carbon atoms launched with its dust are simply turning on for imagers to catch a traditional inexperienced coma. By the tip of July, the comet is swallowed by twilight — see you in three months!
Rapidly swing northwest to the toes of Ursa Main, the place 13P/Olbers is touring via Lynx and Leo Minor. It reached perihelion June 29 and can give us three extra months of telescopic viewing. Binocular observers, problem your self to seek out the Eighth-magnitude glow. Push the magnification previous 100x and word that Olbers ought to be lopsided in comparison with spiral galaxy NGC 2841, some 9° to the north on July 8. Whose core is sharpest and brightest?
Want an in a single day comet? Deliver alongside a great chart that will help you navigate the forest of Seventh-magnitude stars between Cepheus and Draco to get to the difficult Tenth-magnitude C/2021 S3 (PanSTARRS).
Finding Asteroids: Sweetening the (tea)pot
Inside attain of binoculars from the suburbs, dwarf planet 1 Ceres offers us a pleasant and straightforward asteroid search this summer season. Stargazers acquainted with the guts of the galaxy know the gathering of stars referred to as the Teapot of Sagittarius. Magnitude 2.6 Zeta (ζ) Sagittarii anchors the bottom of the Teapot’s deal with and will likely be our signpost to seek out Ceres.
The big dwarf planet (roughly 600 miles throughout) displays probably the most daylight at opposition on the Fifth, elevating it to magnitude 7.3 and leaving it largely uncontested within the eyepiece by the legions of fainter stars towards the galaxy’s hub. You’ll be able to observe its nightly shift in opposition to the background by penciling three or 4 stars onto a logbook sheet and returning a night or two later to substantiate the purpose that moved.
On the twentieth, Ceres is sliding away from a trapezoid of stars (fainter than the limiting magnitude beneath); when you keep up late you would possibly discover its tiny shift. For fun, are you able to see it on the nineteenth, a mere two lunar diameters south of the nearly Full Moon?
