April 2026 Calendar
At any moment of the day, countless awe-inspiring celestial events are unfolding in the sky. With a universe of options, it can be hard to pin down what to observe. The purpose of this calendar is to provide a peek into what’s happening in the sky and in the world of astronomy in general and provide a quick list of highlights that can jump start your own explorations.
April 3 – Mercury at Greatest Western Elongation
Mercury will be a bright presence in the pre-dawn sky — especially for those in the Southern Hemisphere — as the planet achieves a prime position for early morning viewing. Because it is always so close to the Sun, Mercury is usually lost in its glare. But on this day, it will be at its greatest western elongation or at its furthest point to the west of the Sun, which means it will rise well before the Sun in some places. A clear sunrise horizon is essential for viewing Mercury. While this often-elusive planet will be visible to the naked eye, a pair of binoculars or a small telescope could provide additional details.
April 6 – Moon near Antares
The waning gibbous Moon and the red supergiant Antares will be making a close pass on April 6. Even though they do not really share celestial real estate, it will seem like they do as they move closer together in the southeast sky until they are visually separated by mere degrees. Antares, which means “Rival of Mars” in Greek, is often mistaken for Mars due to its similar reddish hue. Generally identified as the 16th brightest star in the sky, Antares is an irregular variable with a red-orange glow that makes it truly pop. Closer observations with a moderate telescope could reveal its blue companion star, which can be highly challenging to discern.
Astrophotographer Christopher Sullivan captured this image of the Leo Triplet galaxy group with the aid of an Explore Scientific f/3.9 N208-CF Newtonian and HR Variable Coma Corrector.
All month: Leo's Galactic Offerings
Observers wanting to make the most of a mild April night can find an abundance of brilliant stars and inspiring galaxies in the Leo constellation as it prominently prowls the celestial ecliptic. Among its impressive list of observing treats, one of the most popular is the Leo Triplet Galaxy Group, which consists of the intermediate spiral galaxies Messier 65 and Messier 66 as well as the edge-on unbarred spiral galaxy NGC 3628, which has a distinct band of dust. The Leo constellation is also home to the barred spiral galaxy Messier 95, which has a distinct ring-shaped star-forming region surrounding its core; the intermediate spiral galaxy Messier 96, the elliptical galaxy Messier 105 and the Leo Ring - a cloud of helium and hydrogen gas that is orbiting two galaxies.
April 12 - Yuri’s Night: World Space Party
When it comes to space exploration, April 12th has long held profound significance. It was on that date in 1961 that cosmonaut Yuri Gagarin became the first human in outer space after he blasted off for a 108-minute flight aboard the Soviet space program’s Vostok 1 spacecraft. Although brief, this journey was a monumental milestone that ignited an international passion for space exploration. To commemorate this historic event and ensure that passion continues to thrive, organizers held the first Yuri’s Night on April 12, 2001, and, it has grown every year since. Dubbed a World Space Party, the event is a “global celebration of humanity’s past, present and future in space.” Although the anniversary of Yuri Gagarin’s flight is the foundation of the celebration, it also coincides with another April 12th milestone - the 1981 inaugural launch of NASA’s Space Shuttle, which was the world’s first reusable spacecraft and a catalyst for international cooperation. For more information or a schedule of the hundreds of related parties across the globe, visit www.yurisnight.net.
April 13-20 – International Dark Sky Week
Perfectly timed to coincide with Global Astronomy Month, International Dark Sky Week will kick off its annual campaign to shine a figurative light on the very real problem of light pollution on April 13. Held each year since 2003, the week-long awareness event was the idea of Jennifer Barlow, a high school student on a mission to preserve the wonder of the night sky for future generations. The goals for the week are fairly simple: Celebrate the beauty of the stars, raise awareness about the negative effects of light pollution and embolden people to act to reduce the problem. Organizers encourage individuals around the globe to mark the week in a range of ways such as hosting star parties, sharing their thoughts about the issue on social media, participating in an IDSW activity or simply visiting the website to find out more about the topic and what changes they can make. For more information on International Dark Sky Week and its associated events, visit idsw.darksky.org.
April 22 - Waxing Moon and Jupiter
Two of the brightest celestial objects will pair up in the night sky as Jupiter reaches conjunction with the waxing crescent Moon on April 22. Although both will lie in the constellation Gemini, they will not be close enough to observe together in a telescope’s field of view. However, the pairing can be easily enjoyed by the naked eye. With the naked eye, Jupiter will manifest as a bright point of light, but a modest telescope may reveal the giant planet’s impressive cloud belts, its turbulent Great Red Spot or any of the four Galilean moons.
April 22-23 – Lyrids Meteor Shower
This week one of the oldest meteor showers on record is taking its annual turn in the skies. The Lyrids, which are caused by the Earth’s passage through debris left behind by Comet Thatcher, are set to peak in the predawn hours of April 22nd with an average hourly meteor count between 10 and 20. Especially favorable for the northern hemisphere, the Lyrids appear to radiate from a point near the bright star Vega in the Lyra constellation. However, observers should look at a dark patch of sky about 90 degrees away from the radiant point to see the most meteors. To view the Lyrid meteors, which have been known to briefly leave behind glowing dust trails, all you need is your naked eye and a good place to lie down under an open sky.
April 25 – Moon Pairs Up With Regulus
Near the end of the month, the waxing gibbous Moon will occult Regulus - the brightest star in the Leo constellation - for millions of observers in the Americas. During an occultation, one celestial object visually passes in front of another object – briefly blocking our view. For many observers, the occultation will begin in daylight, so they will miss Regulus disappear behind the Moon but will witness its reemergence in twilight. Millions of observers outside of the occultation zone will be treated to a close conjunction of the two celestial treats. Boasting an apparent visual magnitude of 1.35, the blue-white Regulus anchors the sickle-shaped asterism that defines the head of the lion and is said to represent the beast’s heart. Although it appears as a single point of light to the unaided eye, Regulus is a multiple star system that can be at least partially resolved with large aperture binoculars.
Astrophotographer James Gossage captured this image of the Southern Pinwheel Galaxy (Messier 83) with the aid of an Explore Scientific FCD100 Series ED102 Air-Spaced Triplet Refractor.
CONSTELLATION SPOTLIGHT: Hydra
April is an ideal time to view the massive Hydra Constellation, which winds its way across southern skies as a celestial incarnation of the water snake. As the largest and longest of the 88 constellations, Hydra covers a 1,303 square degree area in the sky.
Defined by 17 stars, it is visible from 83° South to 54° North. In terms of stars, its brightest is Alphard (Alpha Hydrae), which is a barium-rich giant star with an orange hue and an apparent visual magnitude near 2. The constellation also offers R Hydrae - a pulsating variable star that experiences intense changes in magnitude; Epsilon Hydrae - a multiple star system that includes a spectroscopic binary; Gamma Hydrae - a yellow giant; V Hydrae - a carbon star that is one of the reddest visible stars; and U Hydrae - a carbon star that can be seen with the unaided eye.
Even though Hydra is not as packed with observing targets as one might expect, it still has several notable deep sky objects. One of the easiest to spot is Messier 48, an open cluster that can be seen as a hazy patch with the naked eye or resolved into dozens of brilliant stars with a pair of binoculars. Messier 68 is a stunning globular cluster with a round appearance that puts on a great show in a larger telescope. The constellation also contains Messier 83. Known as the Southern Pinwheel Galaxy, this deep sky treat is one of the closest and brightest barred spiral galaxies. Home to six known supernovae, this active galaxy gloriously displays its spiral arm structure when viewed through a moderate to large telescope. Beyond the Messier catalog, Hydra also boasts an intriguing planetary nebula known as the Ghost of Jupiter. This feature has a bluish hue and can be easily examined through a telescope.
WANT TO NAVIGATE THE NIGHT SKY WITH EASE?
The Tirion Double-Sided Multi-Latitude Planisphere is a comprehensive sky map for northern hemisphere stargazers located between the equator and latitude 60° north that makes it easy to identify what constellations and major celestial objects are up in your night sky based on the date and time.
This night sky guide, which features maps crafted by noted celestial cartographer Wil Tirion, uses a double-sided design to minimize the distortion that is inherent to any polar-centered projection. This design choice means observers can see truer representations of the constellations located outside the equator (noted by a green line) by simply flipping the planisphere over.
In addition to showcasing constellations, this planisphere indicates the location of notable variable stars, open clusters, nebulae and galaxies. Other features include a line representing the ecliptic, a faint blue band for the Milky Way and a magnitude scale that indicates the brightness of the stars that are shown.
This astronomy planisphere is made of durable plastic that easily wipes clean, and the rotating components are secured with sturdy brass rivets for smooth manipulation. Guidance for using your sky map is printed on the device for quick reference.