FRIDAY, MAY 1
■ Full Moon; exactly full at 1:23 p.m. EDT. The Moon, in Libra, rises in the east-southeast in twilight 30 or 40 minutes after sunset, depending on your location (in North America).
Once the sky is dark enough, find Spica about two fists upper right of the Moon, and brighter Arcturus about four fists to the Moon’s upper left.
■ Meanwhile Venus shines in the western sky in twilight. Now it’s above Aldebaran and the delicate Pleiades, as shown below. Watch as they each come into view in their order of brightness: Venus is magnitude –3.9, Aldebaran is 80 times fainter at magnitude +0.9, and the brightest star of the Pleiades (Alcyone) is six times fainter than Aldebaran at mag. +2.8. Later in the week the Pleiades will become very low and even harder to see.
■ And low in brightening dawn, Saturn and Mars continue to pull farther apart as shown below. On Saturday morning April 26th they were 4° apart. Now on the morning of May 2nd they’re separated by 8°. A week later on the 9th they’ll be 13° apart. The change is almost entirely due to Saturn moving up and right with respect to your dawn horizon, while Mars appears to stay at nearly a fixed height.
SATURDAY, MAY 2
■ A gigantic asterism you can easily trace out is the Great Diamond, some 50° tall and extending over five constellations, as shown below. It now leans left in the southeast after dusk, over the Moon tonight.
Start with Spica, its bottom. Upper left from Spica is bright Arcturus. Almost as far upper right from Arcturus is fainter Cor Caroli, the Diamond’s 3rd magnitude top. A similar distance lower right from there is Denebola, the 2nd-magnitude tailtip of Leo. And then back to Spica.
The bottom three of these stars, the brightest, form an equilateral triangle. The late Sky & Telescope columnist George Lovi may have been the first to name this the “Spring Triangle,” paralleling those of summer and winter.
The Great Diamond (Spica – Arcturus – Cor Caroli – Denebola) and the Spring Triangle tilt left in the southeastern sky after dark in late April and early May. The Diamond is a huge 50° tall.
Its stars diminish in brightness as you go counterclockwise from Arcturus, the brightest. Arcturus is magnitude 0, Spica is 1st mag, Denebola is 2nd, and Cor Caroli is 3rd. (To be exact: -0.1, 1.0, 2.1, 2.8.)
If you have a dark sky or binoculars, look almost halfway from Cor Caroli to Denebola for the very large, sparse Coma Berenices star cluster. It spans some 4°, about the size of a ping-pong ball held at arm’s length. Its brightest central stars form an upside-down Y.
Work through more of the Coma Star Cluster as seen in binoculars with Matt Wedel’s “Binocular Highlight” column in the May Sky & Telescope, page 43.
SUNDAY, MAY 3
■ Summer is still seven weeks away, but the Summer Triangle is beginning to make its appearance in the east, one star after another. The first in view is bright Vega. It’s already visible low in the northeast as twilight fades.
Next up is Deneb, lower left of Vega by two or three fists at arm’s length. Deneb takes about an hour to appear after Vega does, depending on your latitude.
The third is Altair, which shows up farther off to their lower right by midnight.
■ Late tonight the bright waning gibbous Moon roses in the company of orange Antares and the rest of upper Scorpius, as shown below.
MONDAY, MAY 4
■ This is the time of year when nightfall catches Leo the Lion walking horizontally at his highest across the south. At the end of twilight, face south-southwest and look very high up from there. The brightest star you’ll encounter is Regulus, Leo’s first-magnitude forefoot. Regulus is also the bottom of the Sickle of Leo: a backward question mark about a fist and a half tall that outlines the lion’s leading foot, chest, and mane.
As the evening proceeds, Leo starts walking downslope toward the west, on his way to departing into the sunset in early summer.
TUESDAY, MAY 5
■ These spring evenings, the long, dim sea serpent Hydra snakes almost level far across the southern sky. Find his head, a rather dim asterism about the size of your thumbprint at arm’s length, in the southwest. It’s a little more than halfway from Regulus to Procyon. Left or lower left of Hydra’s head, by about a fist and a half, is 2nd-magnitude Alphard, Hydra’s lonely orange heart.
Hydra’s dim, irregular body and tail stretch from there almost all the way to Libra rising in the southeast. He carries Crater and Corvus on his back.
Hydra’s star pattern, from forehead to tail-tip, is 95° long. That’s more than a quarter of the way around the celestial sphere. No other constellation does that. Even the star pattern of the river Eridanus is only 66° from end to end.
■ The Eta Aquariid meteor shower, usually the best shower of the year for the Southern Hemisphere, should be near its peak early Wednesday morning. However, the sky will be washed with bright waning gibbous moonlight. And even under ideal circumstances, we mid-northern observers see little of this shower.
WEDNESDAY, MAY 6
■ Jupiter’s darkest-surfaced big satellite, Callisto, transits across Jupiter’s bright face tonight from 10:33 p.m. to 2:41 a.m. Eastern Daylight Time. (Convert these times to your own time zone. For observers in eastern North America ,Jupiter sets while the transit is in progress.)
Callisto is having one of its infrequent transit seasons. Its surface is dark enough that Callisto can mimic the shadow of a Jovian moon crossing Jupiter’s bright face, at least once it’s well inside of Jupiter’s dimmer edges. For more about this see the extended caption for the image of Jupiter — with Callisto in transit — below in “This Week’s Planet Roundup.”
While Callisto’s transit is under way, Europa will disappear behind Jupiter’s western limb at 11:36 p.m. EDT, followed by Io doing the same at 2:35 a.m. EDT. Jupiter’s Great Red Spot should transit Jupiter’s central meridian around 12:11 a.m. EDT.)
THURSDAY, MAY 7
■ The high spring constellation Canes Venatici offers the well-known bright double star Cor Caroli as its Alpha, and it also bears the 8th-magnitude spiral galaxy M94, type Sab. But there’s more here too for amateur telescopes, as told by Ken Hewitt-White in his Suburban Skygazer column “Night of the Bloodhounds” in the May Sky & Telescope, page 53.
FRIDAY, MAY 8
■ Spot Venus, the Evening Star, shining bright white in the west-northwest. It’s almost as high now as it’s going to get during this rather low 2026 apparition.
As twilight fades look for Beta Tauri coming in to view above Venus, and Aldebaran coming into view almost twice as far below Venus. Binoculars will help. This evening Venus sits right on the line between those two stars. Tomorrow it will have visibly moved off the line.
■ And to the upper left of Venus the second brightest planet, Jupiter, shines in Gemini as shown below. The sky will have to get good and dark for all the stars of the Twins’ pattern to come into view.
■ Last-quarter Moon tonight (exactly last quarter at 5:10 p.m. EDT on this date. The Moon rises a few hours later, around 2 a.m. local daylight-saving time Saturday morning. By that time maybe you can see that it’s no longer perfectly half lit. It’s in the center of dim Capricornus.
SATURDAY, MAY 9
■ Three zero-magnitude stars shine after dark in May: Arcturus high in the southeast, Vega much lower in the northeast, and Capella in the northwest. They appear so bright because each is at least 60 times as luminous as the Sun, and because they’re all relatively nearby: 37, 25, and 42 light-years from us, respectively.
SUNDAY, MAY 10
■ The Arch of Spring spans the western sky in late twilight, highlighted by Jupiter near its top. Pollux and Castor, lined up roughly horizontally, form the Arch’s top. Watch for them to come out in the fading twilight less than a fist above or upper right of Jupiter. Look far to their lower left for Procyon, and farther to their lower right for Menkalinan and then bright Capella.
This Week’s Planet Roundup
Mercury is hidden low in the glow of sunrise.
Venus (magnitude –3.9) shines bright white in the west-northwest during evening twilight. It now stays in view low above the horizon for about 40 minutes after full dark.
As the stars begin to come out in that part of the sky, look for Beta Tauri above Venus and Aldebaran ever lower below it. Venus crosses the line between them on May 8th.
Mars and Saturn very low in bright sunrise. You’ll need binoculars at least. See the illustration for May 2 near the top of this page.
Jupiter, magnitude –2.0, is the next brightest planet after Venus. It shines high in the west in twilight about 35° to Venus’s upper left. Jupiter sinks all evening and sets around midnight or 1 a.m. on the west-northwest horizon.
Watch Jupiter and Venus close in toward each other for the next six weeks! At their conjunction on June 9th, they’ll pass just 1.6° apart.
In a telescope Jupiter is down to 35 arcseconds wide, nearly as small as we ever see it. Earth is carrying us around toward the far side of the Sun from slow-orbiting Jupiter.
I’ve certainly been fooled! Once when I was using my 12.5-inch reflector and knew the situation beforehand, dark Callisto did seem to look a little grayer than a shadow might. But in astronomy, contrast can sure play tricks. The opposite effect happens when you see our own dark-surfaced Moon sunlit against a darker sky. It looks brilliant white.
For a timetable of all the doings of Jupiter’s moons in April and May, good worldwide, see the May Sky & Telescope, page 51.
Uranus is lost in the sunset.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world’s mid-northern latitudes. Descriptions and graphics that also depend on longitude (mainly Moon positions) are for North America. Eastern Daylight Time (EDT) is Universal Time minus 4 hours. UT is also known as UTC, GMT, or Z time.
Want to become a better astronomer? Learn your way around the constellations. They’re the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
This is an outdoor nature hobby. For a more detailed constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential magazine of astronomy.
For the attitude every amateur astronomer needs, read Jennifer Willis’s Modest Expectations Give Rise to Delight.
Once you get a telescope, to put it to good use you’ll want a much more detailed, large-scale sky atlas (set of charts). The basic standard is the Pocket Sky Atlas, in either the original or Jumbo Edition. Both show all 30,000 stars to magnitude 7.6, and 1,500 deep-sky targets — star clusters, nebulae, and galaxies — to search out among them.
Next up is the larger and deeper Sky Atlas 2000.0, plotting stars to magnitude 8.5; nearly three times as many, as well as many more deep-sky objects. It’s currently out of print, but maybe you can find one used.
The next up, once you know your way around well, are the even larger Interstellarum Deep-Sky Atlas (with 201,000+ stars to magnitude 9.5 and 14,000 deep-sky objects selected to be detectable by eye in very large amateur telescopes), and Uranometria 2000.0 (332,000 stars to mag 9.75, and 10,300 deep-sky objects).
For the necessary tricks, read How to Use a Star Chart with a Telescope. It applies just as much to electronic charts on your phone or tablet — which many observers find handier and more versatile, if sometimes less well designed and contextualized For the necessary tricks, read How to Use a Star Chart with a Telescope. It applies just as much to electronic charts on your phone or tablet — which many observers find handier and more versatile, if sometimes less well designed and contextualized — as it does to charts on paper.
You’ll also want a good deep-sky guidebook. A beloved old classic is the three-volume Burnham’s Celestial Handbook. It was my bedside reading for years. An impressive more modern one is the big Night Sky Observer’s Guide set (2+ volumes) by Kepple and Sanner. The pinnacle for total astro-geeks is the new Annals of the Deep Sky series, currently at 11 volumes as it works its way forward through the constellations alphabetically. So far it’s up to H.
Can computerized telescopes replace charts? Well, I used to say this:
“Not for beginners, I don’t think, unless you prefer spending your time getting finicky technology to work rather than learning how to explore through the sky yourself. As Terence Dickinson and Alan Dyer say in their Backyard Astronomer’s Guide, ‘A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand and a curious mind.’ Without these, ‘the sky never becomes a friendly place.’ “
But things do change. The technology has continued to improve and become more user-friendly — particularly with “plate solving” software that can now recognize any star field to determine exactly where the telescope is pointed — finally bypassing all aiming imperfections in the mount, tripod, gears, bearings and other mechanics, or in the user’s skill in setting up.
The latest revolution is the rise of small, photography-only “smartscopes.” These take advantage of not only today’s pointing technology, but also the vastly better capabilities of imaging chips and image processing compared to the human retina and visual cortex. The most sophisticated image stacking and processing can come built right in. The result is decent deep-sky imaging from shockingly small, low-priced units. The image may be viewable on your phone or computer as it builds up in real time. Some can directly enable contributions to citizen-science projects.
Smartscopes are changing the hobby at the entry level. For more on this revolution see Richard Wright’s “The Rise of the Smart Telescopes” in the November 2025 Sky & Telescope. And read the magazine’s review of this especially small one.
If you get a larger, more conventional computerized scope that you can look through, make sure that its drives can be disengaged so you can swing it around and point it readily by hand when you want to, rather than only slowly by the electric motors (which eat batteries).
Audio sky tour. Out under the evening sky with your
earbuds in place, listen to Kelly Beatty’s monthly
podcast tour of the naked-eye heavens above. It’s free.
“The dangers of not thinking clearly are much greater now than ever before. It’s not that there’s something new in our way of thinking, it’s that credulous and confused thinking can be much more lethal in ways it was never before.”
— Carl Sagan, 1996 , The Demon-Haunted World: Science as a Candle in the Dark
“Facts are stubborn things; and whatever may be our wishes, our inclinations, or the dictates of our passion, they cannot alter the state of facts and evidence.”
— John Adams, 1770, in the summation of his defense of British soldiers in the Boston Massacre trial
“Truly, whoever can make you believe absurdities can make you commit atrocities.”
— Voltaire, 1765, Questions sur les miracles