July 2024 is full of amazing celestial events you won't want to miss. It all kicks off on July 1st with the peak brightness of Comet 13P/Olbers and the breathtaking view of the open star cluster IC 4756. Then, on July 13th, the Moon will put on a show as it passes in front of Spica, creating a mesmerizing lunar occultation.
Mid-month, mark your calendars for the beautiful Full Buck Moon on July 21st. On the same night, you'll get a rare chance to see Mercury at its greatest eastern elongation. Just a couple of days later, on July 23rd, Pluto will be at opposition, making it visible for most of the night.
The month wraps up with a bang, featuring two spectacular meteor showers: the Southern Delta Aquariids on July 29th and the Alpha Capricornids on July 30th. These will offer dazzling displays of meteors and bright fireballs. Get ready for an unforgettable month of stargazing!
8 Celestial Events You Can't Miss in July 2024
- July 1: Comet 13P/Olbers
- July 1: Open Star Cluster IC 4756
- July 13: Lunar Occultation of Spica
- July 21: Full Buck Moon
- July 21: Mercury's Eastern Elongation
- July 23: Pluto's Opposition
- July 29: Southern Delta Aquariids Meteor Shower
- July 30: Alpha Capricornids Meteor Shower
July 1st
A Rare Celestial Visitor: Comet 13P/Olbers to Light Up the Sky
Mark your calendars for July 1st, 2024, because Comet 13P/Olbers is set to dazzle us with its peak brightness. On this night, it will be about 1.18 AU (Astronomical Units) from the Sun and 1.93 AU from Earth.
A Bit of History
Comet 13P/Olbers has a pretty cool backstory. It was discovered by Heinrich Wilhelm Olbers on March 6, 1815. What makes this comet special is that it's a periodic comet, which means it swings back into our part of the solar system every 69 years. This makes its appearances rare and super exciting for astronomers and sky watchers alike.
Why Comets Are So Unpredictable
One of the fascinating things about comets is how unpredictable they are when it comes to their brightness. Their glow comes from sunlight reflecting off the dust in their coma and tail. As the Sun heats up the comet’s nucleus, it turns ice into gas and releases dust. The amount of dust can vary a lot, even from one visit to the next, making it tricky to predict how bright a comet will get.
While astronomers can pinpoint where a comet will be, figuring out its brightness is a lot harder. For most comets, we don't even try to guess how bright they'll be. But for Comet 13P/Olbers, we have data from the British Astronomical Association (BAA), which often updates its estimates based on what amateur astronomers observe.
What to Expect on July 1st
According to the latest info from the BAA, Comet 13P/Olbers might reach a magnitude of around 6.1 on July 1st, 2024. This means it won’t be visible to the naked eye, but you should be able to spot it with a decent pair of binoculars.
How to Spot Comet 13P/Olbers
Here’s how you can find Comet 13P/Olbers on July 1st:
- Right Ascension: 08h 36m 20s
- Declination: 42° 23' N
- Constellation: Lynx
- Magnitude: 6.1
July 1st
Graff's Cluster: A Stellar Delight in the Serpens Cauda Constellation
On July 1st, the open star cluster IC 4756, also known as Graff's Cluster, will be perfectly positioned for evening viewing, reaching its peak around midnight local time. Found in the constellation Serpens Cauda, IC 4756 shines with a magnitude of 4.6, offering a spectacular sight for anyone who loves the night sky.
Discovering IC 4756
IC 4756 is situated at a declination of 5°27'N, making it visible from most parts of the world, from latitudes 75°N to 64°S. While it’s too faint to see with the naked eye unless you're in a very dark area, you can easily spot it with binoculars or a small telescope.
This star cluster is about 1,300 light-years away and is roughly 800 million years old. It's a loose collection of several hundred stars bound together by gravity, creating a stunning and expansive pattern in the sky. Discovered by German astronomer Max Wolf in the early 20th century, IC 4756 has become a favorite target for both professional and amateur astronomers.
The Beauty and Significance of IC 4756
Part of the Milky Way's rich tapestry, IC 4756 offers a glimpse into our galaxy's past. The stars in this cluster are thought to have formed around the same time from the same molecular cloud. This makes IC 4756 a fascinating object of study, providing insights into stellar evolution and the dynamics of star clusters.
How to Find IC 4756
Here’s where to look for IC 4756 on July 1st:
- Right Ascension: 18h 38m 50s
- Declination: 5° 27' N
- Constellation: Serpens Cauda
- Magnitude: 4.6
July 13th
Celestial Ballet: Witness the Moon's Dance with Spica
The Moon will glide in front of Spica (Alpha Virginis), creating a stunning lunar occultation on July 13th. This event will be visible from parts of the world, including the contiguous United States, Mexico, eastern Canada, and Nicaragua. If you're in the contiguous United States, you can catch this celestial spectacle between 10:36 PM and 12:55 AM ET.
What is a Lunar Occultation?
A lunar occultation occurs when the Moon passes in front of a star or planet, temporarily hiding it from view. Because the Moon is so close to Earth, its position in the sky can vary by up to two degrees depending on your location. This means that the occultation is only visible from certain areas.
Why It Matters
These events are not just visually impressive—they also help astronomers learn more about the Moon and the stars it covers. Historically, occultations were used to measure distances and refine our understanding of celestial mechanics.
During the occultation on July 13th, the Moon will be six days past new moon, making it 52% illuminated. Spica, one of the brightest stars in the night sky, will disappear behind the dark side of the Moon and reappear from the bright side. This spectacular sight highlights the contrast between Spica’s brilliant light and the dark edge of the Moon.
How to Watch
Here’s where to look for Spica at the time of the occultation:
- Right Ascension: 13h 25m 10s
- Declination: 11° 09' S
- Constellation: Virgo
- Magnitude: 1.1
July 21st
Bask in the Glow of July's Full Buck Moon
Keep an eye out for Sunday, July 21st, when the full Buck Moon will light up the night sky. It will reach peak illumination at 6:17 AM Eastern Time. Although it will be below the horizon at that exact moment, make sure to look southeast after sunset to see it rise gloriously into the sky.
Why is it Called the Buck Moon?
The name "Buck Moon" comes from The Old Farmer’s Almanac, which pulls from Native American, Colonial American, and European traditions. Historically, these full Moon names were used for the entire lunar month in which they occurred. July’s full Moon is called the Buck Moon because male deer, or bucks, are growing their antlers during this time. Bucks shed and regrow their antlers each year, with each set becoming larger and more impressive.
Understanding the Full Moon
A full Moon happens when the Moon is directly opposite the Sun in the sky, as seen from Earth. Even though the exact moment of fullness won’t look any different to the naked eye, you can enjoy the Buck Moon’s beauty throughout the night. On July 21st, when the Moon reaches its full phase, it will appear in the constellation Capricornus, and positioned about 229,000 miles from Earth.
How to Enjoy the Full Buck Moon
Here are the coordinates for the Moon at its full phase:
- Right Ascension: 20h 08m 00s
- Declination: 25° 01' S
- Constellation: Capricornus
- Angular Size: 32' 17"
July 21st
Chasing Mercury: Catch the Dazzling Planet at Its Best
July 21st is a special date for sky watchers because Mercury will be at its greatest eastern elongation. This marks its farthest separation from the Sun during its evening apparition from June to August 2024. On this night, Mercury will shine brightly at magnitude 0.3, providing one of the best chances to see this elusive planet.
Understanding Mercury's Elongation
Mercury, the smallest planet in our solar system, orbits closest to the Sun. Because of its proximity, it always appears near the Sun in our sky and is often lost in its glare. It’s observable only during brief periods around its greatest elongations—when it reaches its maximum distance from the Sun in the sky. These moments happen roughly every 3-4 months, alternating between the morning and evening skies depending on whether Mercury lies to the east or west of the Sun.
What to Expect on July 21st
During the June-August 2024 evening apparition, Mercury will reach a maximum separation of 26° east of the Sun. This means it will be visible in the western sky after sunset, shining in the constellation Leo. After this point, Mercury will quickly fade as it heads toward inferior conjunction. At inferior conjunction, Mercury passes between Earth and the Sun, turning its unilluminated side towards us and appearing as a thin, barely visible crescent. Since Mercury can only be observed during twilight, it becomes particularly challenging to find when it's in this crescent phase.
How to Find Mercury
Here are the details for spotting Mercury at its greatest elongation:
- Right Ascension: 09h 53m 10s
- Declination: 11° 51' N
- Constellation: Leo
- Magnitude: 0.3
- Angular Size: 7.8"
For comparison, here are the Sun’s coordinates at the same time:
- Right Ascension: 08h 06m
- Declination: 20° 15' N
- Constellation: Cancer
- Magnitude: -26.7
- Angular Size: 31' 29"
July 23rd
Discover Distant Pluto: Witness the Dwarf Planet at Opposition
On July 23rd, Pluto will be at opposition. This means Pluto will lie directly opposite the Sun in the sky, making it visible for most of the night. Located in the constellation Capricornus, Pluto will reach its highest point around midnight local time.
What Happens During Opposition?
At opposition, Pluto is also at its closest approach to Earth, known as perigee, making it appear at its brightest. However, given that Pluto orbits at an average distance of 39.45 AU (Astronomical Units) from the Sun, its brightness doesn't change much between opposition and solar conjunction.
When Pluto is at opposition, it rises as the Sun sets and sets as the Sun rises. Despite being at its closest point to Earth, Pluto remains so distant that it appears as a tiny, star-like point of light, even through a telescope. At the time of opposition, Pluto will be about 34.05 AU from Earth with a peak brightness of magnitude 15.0.
A Brief History of Pluto
Pluto was discovered in 1930 by Clyde Tombaugh and was long considered the ninth planet of our solar system. However, in 2006, the International Astronomical Union reclassified it as a dwarf planet. This change reflects our growing understanding of the diverse bodies that inhabit the Kuiper Belt, the region of the solar system where Pluto resides.
Pluto's orbit is highly elliptical, taking it from 30 to 49 AU from the Sun, and it takes 248 Earth years to complete one orbit. Despite its great distance, observing Pluto offers a fascinating glimpse into the outer reaches of our solar system and the objects that populate this distant frontier.
How to Find Pluto
Here are Pluto's celestial coordinates at the moment it passes opposition:
- Right Ascension: 20h 15m 20s
- Declination: 23° 06' S
- Constellation: Capricornus
- Magnitude: 15.0
July 29th
Spectacular Southern Delta Aquariids: Peak Meteor Shower Viewing
Get ready for a celestial show as the Southern Delta Aquariids meteor shower peaks on the night of July 29th into the early hours of July 30th. This meteor shower is active from July 18th to August 21st, 2024, and is best viewed from the southern tropics. However, northern skywatchers can still catch a glimpse, though the radiant will be lower in the southern sky, resulting in fewer visible meteors.
What to Expect
The Southern Delta Aquariids are known for their faint meteors, which usually lack persistent trains and fireballs. Despite this, they still put on a good show, with peak rates occurring during the week centered around the maximum night. The shower has an expected Zenithal Hourly Rate (ZHR) of 25 meteors per hour, with meteors traveling at a moderate velocity of 25 miles per second (40 km/s).
The Parent Comet
The parent object of the Southern Delta Aquariids is believed to be comet 96P/Machholz. This adds an extra layer of interest for comet enthusiasts, linking the meteors we see to a specific celestial body.
Viewing Conditions
In 2024, moonlight will be a minor factor thanks to a waning crescent moon that will rise in the early morning hours. On the peak night, the moon will be 30% full, which means it won’t significantly interfere with your meteor viewing experience. If the moon is above your horizon while you’re observing, try looking more toward the southwestern sky to avoid its glare.
How to Watch the Southern Delta Aquariids
Here are the details for the Southern Delta Aquariids:
- Radiant: Right Ascension 22h 42m, Declination -16.3°
- ZHR: 25 meteors per hour
- Velocity: 25 miles/sec (40 km/sec)
- Parent Object: 96P/Machholz
For the best viewing experience, find a dark spot away from city lights and let your eyes adjust to the darkness for about 20-30 minutes. Lie back, look up, and enjoy the show as the meteors streak across the sky. Whether you’re an experienced stargazer or just love watching shooting stars, the Southern Delta Aquariids promise a night of spectacular sights.
July 30th
Bright Fireballs Await: Alpha Capricornids Peak
The Alpha Capricornids meteor shower lights up the sky from July 7th to August 15th, 2024. The peak will be on the night of July 30th into the early hours of July 31st. Although this shower typically produces around five meteors per hour, it’s famous for its bright fireballs that are sure to impress both seasoned stargazers and casual observers.
What to Expect
The Alpha Capricornids are known for their spectacular fireballs—brilliant, long-lasting meteors that can light up the night sky. Even though there are fewer meteors compared to other showers, the ones you do see will likely be memorable. This meteor shower is equally visible from both sides of the equator, making it a perfect event for everyone to enjoy. The meteors are slow-moving, traveling at a leisurely 14 miles per second (22 km/s), which makes them easier to spot and admire.
Viewing Conditions
On the peak night, the moon will be only 20% full, providing mostly dark skies that are ideal for meteor watching. The Alpha Capricornids have a "plateau-like" maximum, meaning you’ll have a good chance of seeing meteors throughout the night, not just at the peak.
Key Details for the Alpha Capricornids
- Radiant: Right Ascension 20h 26m, Declination -9.12°
- ZHR: 5 meteors per hour
- Velocity: 14 miles/sec (22 km/sec)
- Parent Object: Comet 169P/NEAT
How to Enjoy the Meteor Shower
To make the most of your meteor shower experience, follow these tips:
- Find a Dark Spot: Get away from city lights and let your eyes adjust to the darkness for about 20-30 minutes.
- Look Up: Lie back and gaze at the sky. No special equipment is needed, just your eyes and some patience.
- Be Comfortable: Bring a blanket or a reclining chair, some snacks, and maybe some company to enjoy the spectacle with.