Maximize your planetary pleasure and get re-acquainted with Earth’s siblings during the June 29th dawn planet parade.

Planet parade
See five of the eight planets plus the last quarter Moon in a nicely-spaced lineup at the start of morning twilight on June 29th.

Earlier this month the online universe was buzzing with news about the "parade of the planets." Maps showed Mercury, Venus, Jupiter, Mars, Saturn, and the Moon shoulder-to-shoulder at dawn. Would that it were true! Planet lineups are wonderful sights, but this prediction was, to put it kindly, overly optimistic.

From mid-northern latitudes, Mars and Saturn have been the sole planets visible at dawn since April. They've only come into their own in the past month, climbing high enough to put up a good fight against the growing light. Come the end of the June, Jupiter and the waning Moon will join the crew. With improved visibility of Uranus and Neptune, the stage will soon be set for a proper planetary alignment on June 29th at dawn. Earth's a given, of course, making for six planets and numerous moons strung across the eastern sky like tiki lamps. (Venus and Mercury can't attend because they're too close to the Sun in the evening sky to see from mid-latitudes.)

Ever since Jupiter departed the evening sky in April, I've missed seeing Earth's siblings. I'm eager to get re-acquainted. Let's see what each planet has to offer telescopic observers.


Jupiter June 29, 2024
Io's shadow will transit Jupiter on the morning of June 29th. Time shown is 4:30 a.m. CDT. North is at upper left.

The gas giant climbs to 12° altitude about 45 minutes before sunrise — high enough for observers across much of North America to discern Io's shadow transiting over the South Equatorial Belt (SEB) from 8:21-10:31 UT (4:21-6:31 EDT). The other three Galilean moons will also be visible.

Jupiter spends this year in Taurus and comes to opposition on December 7th. Its high declination will make it a riveting sight during the fall and winter months.


Uranus June 29, 2024
If you seek Uranus early, binoculars will suffice. Come mid-twilight you'll need a small telescope. The 5.8-magnitude planet stands 10° high about 90 minutes before sunrise. The Pleiades and nearby bright field stars will help guide you there. The position shown here is for June 29th with stars to magnitude 7.

With an apparent diameter of 3.5 arcseconds, Uranus appears only a little smaller than Mars. Thanks to its fortuitous location near the Pleiades star cluster it should be relatively easy to find in binoculars.

Given its relatively low altitude at twilight, though those eager to see the planet's brightest moons, Titania and Oberon, will have to wait till another day.


Mars in spring 2024
Despite its tiny size in June, Mars's more prominent features are detectable, including the South Polar Cap and the thumb-shaped volcanic plain Syrtis Major.
Paul Maxson (left) and Frank Melillo (right)

Just a teeny thing at 5.4 arcseconds across, and looking gibbous-y at 91% illuminated, most of us will see little more than the Red Planet's phase in a telescope. Observers blessed with excellent seeing can look for the most prominent surface markings with the help of S&T's Mars Profiler and magnifications of 300⨯ or more.

It's currently summer in the planet's southern hemisphere with the South Polar Cap in rapid retreat. Look for the feature while you can — the North Polar Cap will be tipped our way during the planet's upcoming opposition on January 16, 2025.

Waning Moon

When was the last time you got a good look at the third-quarter Moon? Many of us don't, because it rises around 1 a.m. local time. When I do make the effort, the Moon looks strangely unfamiliar, because I usually see it during the lunar afternoon. Light falls at a different slant and reveals a host of details not seen during evening observation.

Last quarter moon June 29, 2024
Lunar eye candy awaits observers who rise for the late-June planet parade. Clavius is one of the largest craters (231 km) on the near side and hosts a conspicuous chain of smaller craters on its floor.
Virtual Moon Atlas

On June 29th the Moon will be just shy of half-lit and shine high in the southern sky. Lots of great sights cluster along the day-night line, called the terminator, where the mix of sunlight and shadow creates a ravishing landscape. I've highlighted above a few special craters and mountains worth checking out. The most dramatic will be Tycho, an 85-kilometer-wide, relatively fresh crater with a prominent central peak that stands 2 kilometers (6,562 feet) high. Low-angled sunlight should make the summit pop!


Neptune on June 29, 2024
Here are two suggested paths to find Neptune, located in Pisces 10.5° northeast of Saturn. Stars are shown to magnitude 8.0. Both Uranus and Neptune move slowly, so their positions are still good for a couple mornings on either side of June 29th.

With the Moon nearby, 7.9-magnitude Neptune will be the most challenging planet to see in binoculars. On the plus side, it's high enough to observe in a dark sky around 3 a.m. local time, shortly before the start of dawn. If you have an 8-inch or larger instrument, look for the planet's largest and brightest moon, Triton, near greatest elongation about 15″ north of Neptune. A magnification of 250⨯ should nab it.


Saturn on June 29, 2024
Saturn's moons form nearly a straight line on either side of the planet. This view shows them around 4 a.m. CDT on June 29th. North is up.

Saturn's rings are tilted just 1.95° in late June, close to their minimum for the year, so they look more like a skewer than a disk. The narrow inclination makes it easier to ferret out dimmer moons that would otherwise be lost in the rings' glare. Five line up near the planet on Saturday morning, June 29th. The brightest are Titan (8.5) and Rhea (9.9).

Titan transit simulated and real
Titan is Saturn's largest moon with an apparent diameter of 0.76″. The top view depicts the moon over the planet's southern hemisphere on June 30th at 4 a.m. CDT. The bottom image shows the real thing on June 14th at 5 a.m. CDT.
Stellarium (top), Matt Smith (bottom)

Our near-level view of the planet also means the return of Titan transits. There have been several since May, but the best to date occurs on the morning of June 30th from 7:37-12:22 UT (3:37-8:22 EDT). Two more follow on the mornings of July 16th and August 1st.

Titan's shadow transit season begins in November and continues into 2025. While shadow transits are obvious in a small telescope, seeing Titan's disk against Saturn's pastel globe takes a little more concentration and magnification.

Wishing you success all around — and a very festive parade!


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