5 planets will align on March 27 and you won't want to miss it. Here's where to look.
On Mar. 27, a cosmic parade of five planets, the moon and a star cluster will line up in the night sky. Here's how to see the special event.
Science & Tech
On March 27, a planetary parade made up of Mercury, Jupiter, Venus, Mars and Uranus will march across the sky.
At this particular time of the year, amateur astronomers are participating in the Messier Marathon. Originally conceived by the late comet hunter, Don Machholz, it takes place around the time of the new moon, and within a week or so of the Vernal Equinox.
It is during this particular time of year, that all 110 of the various deep sky objects cataloged by the French astronomer, Charles Messier, come into view. Those with telescopes and a good knowledge of the sky, will stay up from dusk to dawn, looking for and logging as many Messier objects as they can. Sometimes, there are organized marathons scheduled, such as at the recent International Star Party in Flagstaff, Arizona. Even for assiduous amateur astronomers, the Messier Marathon poses a significant observing challenge
A different type of challenge will be posed for sky gazers on the evening of March 27. Maybe we could echo the 1986 hit song by The Bangles, for that night will truly be a "Manic Monday" as there will be an opportunity to catch sight of five planets, a famous star cluster and the moon all in one evening.
But like the Messier Marathon bagging all of these objects is going to be a challenge, especially with some of the planets.
In fact, I would strongly suggest that you stake out an observing site with a clear and unobstructed view of the western horizon if you hope to see two of these distant worlds. Make sure you do not have any tall objects — buildings or trees — in that direction. Your best option is looking out over a westward-facing shoreline that is perfectly flat and wide open with nothing to block your view.
And also make sure to have a good pair of binoculars, as they will be extremely beneficial in your making a sighting. The best kind is either 7 x 35 or 7 x 50. The first number refers to magnification — in both cases, "7 power." The second number refers to the size of the objective lens — the large lens at the front of the binocular — measured in millimeters.
If you're hoping to catch a look at the planetary parade, our guides to the best telescopes and best binoculars are a great place to start. If you're looking to snap photos of the night sky in general, check out our guide on how to photograph the moon, as well as our best cameras for astrophotography and best lenses for astrophotography.
Interestingly, our first two planets are studies in contrast. One is the smallest planet (Mercury) and the other is the largest (Jupiter).
Once you have found a proper viewing site, and with binoculars in hand, wait until approximately 20 to 25 minutes after the sun has set. And your viewing time is going to be short. Both planets will set beyond the horizon only 25 to 30 minutes later.
Both planets will be shining brilliantly, Mercury will glow at magnitude -1.4, which is just a trifle dimmer than Sirius, the brightest star in the sky. Jupiter will appear even more dazzling at magnitude -2.1, which is twice as bright as Mercury. But what will make a sighting problematic will be that both may be very difficult to see through the bright evening twilight.
And that's where your binoculars come in.
Your best chance to pick both planets up is initially to slowly sweep low along the western horizon with the binoculars; then after you hopefully have found them, seek them out with your naked eye. Mercury will be to the right of brighter Jupiter. On the evening of March 27, they will be separated by just 1.3 degrees (just over one-finger width at arm's length.)
If you sight them, congratulate yourself. It is no mean feat to catch two planets positioned so close to the setting sun. Within just a day or two, Jupiter will disappear from view into the glare of the sun. Mercury, on the other hand, will be moving away from the sun's vicinity and will become a bit easier to see during the next couple of weeks.
In contrast to Mercury and Jupiter, the third planet on our list will be very easy to see: dazzling Venus, the so-called "Evening Star" (although "Evening Beacon might be a better term). It's the first planet to look for when the sun goes down. Venus is becoming increasingly prominent as it slowly gets higher in our western evening sky with each passing night. Right now, it's setting around 10:15 p.m. local daylight time. But two months from now, Venus will be noticeably higher in the west-northwest sky about an hour after sunset, and not setting until close to midnight.
A planet racing away
The fourth planet on our list is Mars. Several months ago, Mars shone brilliantly because it was relatively close to Earth; back on Nov. 30 it was 50.6 million miles away from us and appeared like a very bright fiery hued star, shining with a steady glow. A week later, like two racing cars going around on a track, we passed Mars in our respective orbits — Earth on the inside and Mars on the outside. And ever since then, we've left Mars far behind — in our side view mirror, preverbally speaking.
On March 27, Mars will be 131.4 million miles (211.4 million km) from Earth — more than 2.5 times more distant than it was late last fall. It has correspondingly faded, appearing only 1/13th as bright compared to early in December. Yet it is still fairly conspicuous because it still ranks among the 21 brightest stars in terms of brightness.
And you can make an instant identification of it, by simply looking up at our fifth celestial object of the evening, the moon. On this night, our natural satellite will resemble a fat crescent phase. And if you look off to the moon's upper left, that bright yellow-orange "star" will be Mars.
Have a Life Saver!
Now, use the binoculars again, and look just off to the left of Mars and you'll catch sight of M35, a star cluster in the constellation of Gemini the Twins. It ranked fifth among my list of personal deep-sky favorites in the wintertime sky. Long-time deep-sky columnist for Sky & Telescope, Walter Scott Houston wrote: (opens in new tab) "I feel that M35 is one of the greatest objects in the heavens. Observers with small telescopes will find it a superb object. The cluster appears as big as the moon and fills the eyepiece with a glitter of bright stars from center to edge. With 15x65 binoculars it was like a fat Life Savers candy, all white and glistening."
Seventh planet from the sun
Our fifth and final planet is the next-to-last out from the sun: Uranus.
Barely visible to the unaided eye on very dark, clear nights, use Venus as a benchmark to find it. On Monday it will be just three degrees — roughly equal to one-third of the width of your clenched fist held at arm's length — to the upper left of that dazzling planet. Again, use your binoculars to scan this region of the sky. What you'll be looking for is a faint star, but the tipoff will be its pale greenish tint. That will be the third largest planet and next to the planet Neptune, the most distant planet from the sun.
There you have it: five planets, a famous star cluster and the moon. Think you'll be able to sight all seven? As we've noted, a few will be easy but others will be more difficult. If skies are clear Monday evening, good luck and good hunting!