FRIDAY, APRIL 17
■ Vega, the Summer Star, already twinkles low in the northeast these April evenings. Find it five or six fists at arm’s length lower left from Arcturus, the brightest star shining high in the east. They’re both magnitude 0.
How high or low will Vega shine for you after dark? That will depend on your latitude. The farther north you are, the earlier Vega rises. If you live in the latitudes of the southern U.S., you’ll have to wait longer for Vega to make its appearance.
■ New Moon (at 7:52 a.m. EDT on this date).
SATURDAY, APRIL 18
■ Low in the west-northwest in twilight, a hair-thin crescent Moon, just 1½ days old, hangs 4° or 5° to the right or lower right of Venus. Binoculars should give a lovely view of earthshine softly illuminating the Moon’s whole night landscape. Venus and the Moon both set soon after complete dark.
SUNDAY, APRIL 19
■ Now the crescent Moon is 2½ days old and about 11° above Venus. Between them as twilight darkens, watch for the Pleiades to come out. As shown above.
Venus will pass by the Pleiades on April 23rd and 24th, missing them by 3°.
■ Saturn is barely emerging from deep in the sunrise glare to join Mercury and Mars as possibly visible extremely low as dawn gets bright. Bring binoculars or a wide-field telescope. On Monday morning the 20th the three planets form a tight line, only 1.7° long, as shown below. Good luck.
MONDAY, APRIL 20
■ Now the thickening crescent Moon hangs about halfway between Venus and Jupiter at nightfall. These are the three brightest objects in the early-evening sky.
WEDNESDAY, APRIL 21
■ Once again we’re in the days of the month when the Moon forms changing quadrilaterals with Jupiter, Pollux, and Castor, as shown below. No two of these shapes are ever alike
This time, the Moon is approaching first quarter when it happens.
TUESDAY, APRIL 22
■ The Moon and Jupiter shine only 3° or 4° apart this evening, as shown above. Over them, I can picture Pollux and Castor as the pinpoint eyes of an invisible being looking down on them. He doesn’t seem friendly.
Jupiter is 2,200 times farther than the Moon this evening, and it’s 40 times larger in diameter than the Moon. Your internal visual experience that the Moon and Jupiter are actually close together is as different from external reality as my experience of Pollux and Castor as the eyes of an invisible creature.
To get a true sense of the reality, look at Jupiter and its lineup of four Galilean satellites with binoculars or a telescope. Each of those moons of Jupiter is similar in size, more or less, to our own Moon so close in the foreground.
THURSDAY, APRIL 23
■ First-quarter Moon (exactly so at 10:32 p.m. EDT tonight). Its curved side points toward Jupiter, Pollux, and Castor after dark, as shown in the twilight scene above.
■ Venus in late twilight is passing its closest by the Pleiades today, as shown below.
■ A Venus-Uranus challenge: Right near the end of twilight this evening, try using optical aid to pick out the tiny, 6th-magnitude dot of Uranus dot ¾° to Venus’s left or lower left (for evening in North America). Their separation is about an eighth the width of a typical binocular’s field of view, or nearly the width of a typical 60x eyepiece’s field in a telescope. No stars in the area are bright enough to misidentify as Uranus.
FRIDAY, APRIL 24
■ The Moon will occult 1st-magnitude Regulus for most of North and Central America today. Regulus will vanish behind the Moon’s dark limb during twilight for the much of the Eastern Seaboard, but in late afternoon’s broad daylight for observers farther west. Your telescope may be able to show Regulus through a clear blue sky! For full details, open Bob King’s See the Moon Hide Regulus.
The Moon in these scenes is always drawn about three times its actual apparent size, and its placement is exact for an observer at latitude 40° N, longitude 90° (in Illinois near the population center of North America).
SUNDAY, APRIL 26
■ As night descends, look up in the west for Pollux and Castor lined up almost horizontally (depending on your latitude). These two stars, the heads of the Gemini twins, form the top of the enormous Arch of Spring. To their lower left is Procyon, the left end of the Arch. Farther to their lower right is the other end, formed by 2nd-magnitude Menkalinan (Beta Aurigae) and then brilliant Capella. The whole thing sinks in the west through the evening.
Modern skywatchers are not alone in seeing the Arch of Spring as one big asterism. Extend it down past Procyon to add Sirius, and you’ve got the Hawai‘ian Canoe-Bailer of Makali‘i. Looks big enough to bail the whole ocean.
This Week’s Planet Roundup
Mercury, Mars, Saturn and Neptune are very low in the brightening glow of sunrise. Using binoculars or a telescope at low power, you might try for them just a few degrees above the horizon almost due east about 20 minutes before sunrise.
Your best chance will be for Mercury, the brightest at about magnitude –0.3 (before atmospheric extinction). Saturn and Mars are only magnitudes +0.9 and +1.2, and forget 8th-magnitude Neptune. In fact, good luck with any of them.
On Monday morning April 20th the three will form a small, diagonal line a little less than 2° long, as shown under April 19 above.
Venus, bright at magnitude –3.9, gleams low in the west-northwest in evening twilight, just a bit higher each week. An hour after sunset you’ll find it still about a fist at arm’s length above horizontal. Venus sets a half hour after twilight ends.
This week Venus passes the Pleiades, always a lovely pairing. Venus is in conjunction with the Pleiades, 3° lower left of them, on Thursday the 23rd.
Jupiter, magnitude –2.0, is next brightest after Venus. It shines high toward the west at nightfall some 50° to Venus’s upper left. Jupiter moves lower through the evening and sets around 1 or 2 a.m. on the west-northwest horizon.
Watch Jupiter and Venus close in toward each other for the next seven weeks! They’ll pass 1.6° apart at their conjunction on June 9th.
Looking much closer, watch Jupiter approaching little Delta Geminorum (Wasat) this week, magnitude 3.5. On Friday the 17th it’s still 1.7° east of Jupiter. By a week later on the 24th they’ll be down to 1.0° apart. They’ll pass closest, 0.6° apart, on April 30th. “The Moon may be able to circle the entire sky in one sidereal month,” writes Gary Seronik in the April Sky & Telescope, page 47, “but Jupiter won’t buzz Wasat again until 2037.”
In a telescope Jupiter is down to 37 arcseconds wide. It’s shrinking and fading as Earth pulls farther ahead of it in our faster orbit around the Sun.
On this side of Jupiter, the north edge of the North Equatorial Belt currently shows a few large “waves,” three of which send tan festoons trailing into the bright North Tropical Zone. More such waves with festoons are waiting to rotate into view around Jupiter’s eastern limb. Contrast them with the larger, familiar blue festoons in the Equatorial Zone.
Blue features are gaps in the high clouds showing clear blue atmosphere below. The “air” on Jupiter is mostly hydrogen and helium, but it’s blue for the same reason we have blue skies on Earth.
Jupiter’s limb looks lightly bluish too. Here we’re peering a long way (at a low angle) through Jupiter’s uppermost clear air above the clouds.
Uranus (magnitude 5.8 in Taurus) is a faint “star” passing in the background of Venus. They’ll be in conjunction, ¾° apart, on April 23rd, but they’ll be very low by the time the sky becomes dark enough. See April 23 above.
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, than 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, imaging-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
“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
“Truly, whoever can make you believe absurdities can make you commit atrocities.”
— Voltaire, 1765