FRIDAY, MARCH 19
■ The Moon this night shines with Mars and Aldebaran, which look nearly similar as proven beneath.
The waxing Moon shines with Aldebaran and Mars on Friday night the 19th, then between the horn-suggestions of Taurus on the 20th (for night within the longitudes of the Americas).■ Pollux and Castor in Gemini cross almost overhead round 7 p.m. this week for those who stay on this planet’s mid-northern latitudes. They go smack overhead as seen from close to latitude 30° north: Austin, Houston and the US Gulf Coast, in addition to northernmost Africa, Tibet, and Shanghai.
The “twin” heads of the Gemini figures are fraternal twins at finest. Pollux is visibly brighter than Castor and pale orange. And as for his or her bodily nature? They’re not even the identical species.Pollux is a single orange big. Castor is a binary pair of two smaller, hotter, white important-sequence stars, a high-quality double in newbie telescopes. If Pollux had been a basketball, Castor A and B can be a tennis ball and a baseball about a half mile aside.
Moreover, every Castor star is intently orbited by an unseen crimson dwarf — a marble in our scale mannequin simply a foot or so from every of the two vibrant primaries.And a very distant tight pair of crimson dwarfs, Castor C, is seen in newbie scopes as a single, 10th-magnitude speck 70 arcseconds south-southeast of the principle pair. In our scale mannequin, they might be a pair of marbles about three inches aside at least 10 miles from Castor A and B.
Read extra in Fred Schaaf’s “Gemini’s Like and Unlike Twins” within the March Sky & Telescope, web page 45.
SATURDAY, MARCH 20
■ Now the Moon shines between the horn suggestions of Taurus, Beta and Zeta Tauri, as proven above. These two stars type a lengthy rectangle with Mars and Aldebaran: a momentary asterism particular to mid-March 2021.
■ Earth crosses the March equinox level on its orbit at 5:37 a.m. EDT on this date. This when the Sun crosses the equator (each Earth’s equator and, equivalently, the celestial equator), heading north. Spring begins within the Northern Hemisphere, fall within the Southern Hemisphere. And no, eggs do not steadiness at the moment any higher than they normally do, in case somebody tries to inform you that.
SUNDAY, MARCH 21
■ First-quarter Moon. The Moon shines within the ft of Gemini, excessive above Orion in early night.
■ The brightest asteroid, 4 Vesta, continues creeping throughout the rear flank of Leo this week at a binocular-straightforward magnitude 6.1. Use the finder chart with the article about Vesta within the March Sky & Telescope, web page 48.
MONDAY, MARCH 22
■ Now the Moon, simply previous first quarter, shines excessive below Pollux and Castor in early night. Far beneath the Moon is the large Winter Triangle: Procyon on the left, orange Betelgeuse on the precise in Orion’s shoulder, and good Sirius beneath them.
TUESDAY, MARCH 23
■ After darkish look proper of the Moon for Pollux, then Castor. Farther beneath the Moon is Procyon, the Little Dog Star. Even farther beneath Procyon is vibrant white Sirius, the unique Dog Star itself.
WEDNESDAY, MARCH 24
■ The vibrant gibbous Moon shines higher proper of Leo’s Sickle asterism in early night, as proven beneath.By 10 or 11 p.m. the Moon shines on to the precise pf Leo.
And now the waxing gibbous Moon works its method throughout Leo, on its technique to full on the 28th.■ Algol shines at its minimal brightness in early night, whereas it is nonetheless pretty excessive within the northwestern sky, for the Mountain and Pacific time zones of North America. Its mid-eclipse is predicted for 7:55 p.m. Pacific Daylight Time. In one other month Algol shall be primarily gone for the season.
THURSDAY, MARCH 25
■ This night the gibbous Moon shines at the Sickle of Leo, roughly between Regulus to its decrease proper and Algieba (Gamma Leonis) to its higher left, as proven above (relying in your location).This line of three turns vertical, with the Moon nonetheless close to its center, by about 1 a.m.■ Also this night, a line drawn from Aldebaran by way of Mars factors straight to Capella far past.
FRIDAY, MARCH 26
■ Now that spring is below method, Orion has taken up his early-spring posture within the southwest throughout night. He’s tipping westward, and his three-star Belt is popping horizontal.When does Orion’s Belt seem precisely horizontal? That depends upon the place you reside east-west in your time zone, and in your latitude. How nicely are you able to time this occasion? If you are close to your time zone’s normal longitude, anticipate it round 8:40 this night (daylight-saving time). . . roughly.
SATURDAY, MARCH 27
■ The Moon this night is lower than a day from being precisely full. After darkish, look far to its decrease left, by three or 4 fists at arm’s size, for vibrant yellow Arcturus making its method up the japanese sky.By 9 or 10 p.m. daylight-saving time, look two or three fists beneath the Moon for Spica now on the rise.
■ Meanwhile on the opposite aspect of the sky, the signature fall-and-winter constellation Cassiopeia retreats down after darkish. Look for it pretty low within the north-northwest. It’s standing roughly on finish.
For skywatchers at mid-northern latitudes and above, Cassiopeia is circumpolar, by no means going away fully. After midnight it is at its lowest due north, mendacity not fairly horizontally.
This Week’s Planet Roundup
Mercury has sunk out of sight into the glow of dawn.
Venus is out of sight along with the Sun.
Mars (magnitude +1.2, in Taurus) shines excessive within the west after darkish. Mars is almost the dual of Aldebaran to its decrease left, in each brightness and in shade. Mars this week is passing north of Aldebaran, giving it a huge 7° berth for a number of days working. They’re closest (6.9°) on March 20th.
In a telescope Mars is a mere 5½ arcseconds huge: a tiny vibrant blob too small for any floor element.
Jupiter and Saturn have been slowly rising into daybreak view for the final three weeks. Look low within the east-southeast about 50 or 40 minutes earlier than your native dawn time. Saturn is the upper of the 2, but it surely’s a lot dimmer at magnitude +0.7. Jupiter shines at magnitude –2.0 (not counting the atmospheric extinction for one thing so low); search for it some 11° to Saturn’s decrease left. That’s about a fist at arm’s size.
Uranus (magnitude 5.8, in western Aries) is sinking away low within the west proper after the tip of night twilight.
Neptune is hidden within the glare of the Sun.
All descriptions that relate to your horizon — together with the phrases up, down, proper, and left — are written for the world’s mid-northern latitudes. Descriptions that additionally rely on longitude (primarily Moon positions) are for North America.
Eastern Daylight Time, EDT, is Universal Time minus Four hours. Universal Time is also referred to as UT, UTC, GMT, or Z time. For all of the down-and-soiled particulars see Time and the Amateur Astronomer.
Want to change into a higher astronomer? Learn your method across the constellations. They’re the important thing to finding all the pieces fainter and deeper to hunt with binoculars or a telescope.
This is an outside nature interest. For a simple-to-use constellation information overlaying the entire night sky, use the massive month-to-month map within the heart of every subject of Sky & Telescope, the important journal of astronomy.
Once you get a telescope, to place it to good use you may want a detailed, giant-scale sky atlas (set of charts). The primary normal is the Pocket Sky Atlas (in both the unique or Jumbo Edition), which reveals stars to magnitude 7.6.
The Pocket Sky Atlas plots 30,796 stars to magnitude 7.6, and a whole lot of telescopic galaxies, star clusters, and nebulae amongst them. Shown right here is the Jumbo Edition, which is in onerous covers and enlarged for simpler studying outside by crimson flashlight. Sample charts. More concerning the present editions.Next up is the bigger and deeper Sky Atlas 2000.0, plotting stars to magnitude 8.5; almost 3 times as many. The subsequent up, as soon as your method round, are the even bigger Interstellarum atlas (stars to magnitude 9.5) or Uranometria 2000.0 (stars to magnitude 9.75). And you’ll want to learn the way to use sky charts with a telescope.
You’ll additionally need a good deep-sky guidebook, comparable to Sky Atlas 2000.0 Companion by Strong and Sinnott, or the larger (and illustrated) Night Sky Observer’s Guide by Kepple and Sanner.
Can a computerized telescope exchange charts? Not for newcomers, I do not suppose, and never on mounts and tripods which might be lower than high-high quality mechanically, that means heavy and costly. And as Terence Dickinson and Alan Dyer say of 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.”
Audio sky tour. Out below the night sky with yourearbuds in place, hearken to Kelly Beatty’s monthlypodcast tour of the 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.” — John Adams, 1770