What’s Up in the Sky – May, 2021

Things Are Looking Up

With all the safety precautions, vaccine news, and conflict over COVID-19, it’s nice to think about a truly non-partisan topic, and astronomy is just that. Most people simply enjoy the night sky without arguing about it. This month offers a number of opportunities to enjoy some peaceful time.

Let’s begin with some planetary observing. Venus and Mercury are visible near the western horizon after sunset with Mars higher above them. Jupiter and Saturn are visible in the southeastern pre-dawn skies, and with sunrise occurring after 6:00 a.m., it is not that difficult to see them if you are an early riser.

The evening planets are not as easily spotted due to their close proximity to the horizon so binoculars are a must. Since a clear view of the horizon is necessary, the best viewing will be along Lake Michigan, and even though Venus will easily be visible to the naked eye, binoculars will be needed to spot Mercury. Look for Mercury alongside the crescent Moon 40 minutes after sunset on May 13. At the same time on Friday and Saturday, the 14th and 15th, you’ll see that the Moon is now higher in the sky and on the later date will be right next to Mars which forms a right triangle with Castor and Pollux, the twins of Gemini.

Keep following these celestial players through the end of the month. Watch as Venus and Mercury reunite on Friday, May 28, when the separation between them will be less than the size of a Full Moon. Speaking of which, on the night of May 25-26, there will be a “Supermoon”, the closest Full Moon of the year.

For those more experienced amateurs who do most of their observing through a telescope, this month is a good opportunity to check out some double stars. Some excellent candidates for telescopic observing include Algieba (Gamma Leonis), Izar (Epsilon Bootes), Kuma (Nu Draconis) and Iota Cancri. For you neophytes, the scientific names of stars are determined by a distinct set of rules. The Greek letter indicates the relative brightness of the star compared to others in a particular constellation and is followed by the Latin plural name. So the well-known star Alpha Centauri is the brightest star in the constellation Centaurus. There are some exceptions where Beta may be brighter than Alpha, but the designation is usually consistent with this rule.

My favorite double star is Epsilon Lyrae, easily split with binoculars, but not conveniently located until later in the summer so keep it in mind. If you’re just starting to observe double stars, you might want to wait a month or two to observe it. I will let you discover why it’s called the “double-double”.

There are two basic types of double stars: binary stars, which orbit each other, and visual doubles, which appear close to each other but are actually far apart, one behind the other. Distinguishing between the two is not easy and requires measuring their actual distances. Look at the Big Dipper and you will notice that the star in the middle of the handle (Mizar) has a slightly dimmer companion right above it (Alcor). That is an optical double as Alcor is actually three light years farther from us than Mizar is. What makes this so interesting is that both are also binary stars, easily viewed up in the sky.

This month in history:

May 05: Alan Shepard becomes first American in space – 1961
May 06: NASA announces that Canada will build the shuttle robot arm – 1975
May 11: First geostationary weather satellite launched – 1974
May 14: Skylab is launched – 1973
May 20: Pioneer-Venus 1 launched – 1978
May 25: President Kennedy gives speech challenging nation to land astronaut on Moon before the end of the decade – 1961
May 29: First experimental test of Einstein’s General Theory of Relativity performed during total solar eclipse – 1919

What’s Up in the Sky – April, 2021

An Historic Mission on the Red Planet

As winter turns to spring, the “Winter Hexagon” and the popular constellations of Orion and Taurus sink lower in the west, leaving an arc of stars formed by Procyon, Pollux, Castor, and Capella. All month the planet Mars is easily visible, appearing between the two constellations. In the coming months, Mars, along with all its neighbors, will continue to sink lower in the west. If you have trouble picking out which “star” is actually Mars, the planet appears a little brighter than Pollux and a little dimmer than Castor and has a distinct, reddish tone. By the middle of April, the two will be in a straight line with and half way between Betelgeuse and Capella.

Since Mars will soon be out of sight it seems appropriate to recall and reflect on some highlights of events that got the planet in the news recently.

This past February saw three spacecraft from Earth arrive at the red planet: NASA’s Perseverance rover, the United Arab Emirates’ Hope orbiter, and China’s Tianwen-1 orbiter. Recently a friend asked why, with three spacecraft at Mars, are we only hearing about Perseverance, and not the others. The reason is that Perseverance is the only one on the ground, so to speak. The other two are still in orbit around Mars.

The Hope satellite was meant to stay in orbit and has no landing capabilities. It will remain in orbit and study the planet’s climate and atmosphere and how they change over time. China’s Tianwen-1 (“questions to heaven”) is an orbiter and rover mission currently still in orbit. Its rover will land sometime in the next few months.

Perseverance (aka Percy) landed on February 18, making it the fifth rover on the surface of Mars. It landed in the 45 km-wide Jezero Crater, site of a suspected ancient river delta and lake. NASA has named the site in honor of Octavia E. Butler, the award winning American science fiction writer.

The lander took little time getting to work. It has already taken many photos, explored the nearby terrain, and collected samples for geological study. The most exciting event so far, however, has been the launch of Ingenuity Helicopter. Built to actually fly unaided on the surface of Mars, it has made the first powered flight through the atmosphere of another planet. To me, that’s about as cool as it gets. Some folks at NASA apparently agreed with me because a piece of fabric from the wing of the Wright Brothers 1903 airplane, the Wright Flyer, considered to be the first controlled flight on Earth, has been carried to Mars, tucked safely away aboard Ingenuity.

With an extremely successful landing and first few weeks of work getting set up, doing systems checks and launching the Ingenuity Helicopter, Perseverance appears to be ready to further expand our knowledge and understanding of Mars, which is, of course, up in the sky.

This month in history:
April 01: Comet Hale-Bopp nearest Sun – 1997
April 02: First photograph of Sun taken – 1845
April 09: NASA selects original seven Mercury astronauts – 1959
April 12: Yuri Gagarin becomes first human in space – 1961
April 12: Columbia is first space shuttle to be launched – 1981
April 17: Apollo 13 returns to Earth – 1970
April 25: Deployment of Hubble Space Telescope – 1990
April 28: Eugene Shoemaker is born – 1928

What’s Up in the Sky – February, 2021

What’s Up With Betelgeuse?

Last month we focused on one of the most prominent and popular constellations, Orion. Now, as if bright nebulae, stars of all sizes and colors, and a sword and belt recognizable by all weren’t enough, Orion’s brightest and most famous (they named a movie after it) star, Betelgeuse, is once again in the news.

Most readers are familiar with Betelgeuse and its position as Orion’s right shoulder as well as its reddish color (hence the designation, “red giant”). Some might even be aware that the star’s brightness varies periodically over a span of 420 days and this is what made some headlines in January and February of 2020. During that time the drop in brightness was 50% greater than the previous year, making the star appear noticeably dimmer. And astronomers both amateur and professional did take notice. In fact, amateurs are the main source of variable star data and they were astonished as well as being jolted into action.

Since the first observations, scientists have been collecting a plethora of data of all types in order to understand the causes of the star’s dimming. The two main theories are: a rapid increase in new dust in the star’s outer shell, or a rare drop in the temperature of its surface. There were some questions about the possibility of the star going supernova and astronomers aren’t certain about that. Chances are pretty good that it won’t be in our lifetimes.

One thing that is certain this month is that some of the best stars and constellations for observing will be visible, assuming clear skies, and Orion is right in the middle of it all. Find Orion’s belt and follow it down and to the left where you will spot Sirius, the most brilliant star in our sky. Known as the Dog Star, it lies in the constellation Canis Major, the Big Dog. Above and to the left of Sirius is the star Procyon (PRO-see-on) in the constellation Canis Minor, the Little Dog. Procyon and Sirius are known as Orion’s hunting dogs. You’ll notice that Canis Minor consists of only two visible stars. Think of them as the dog’s tail. Procyon, Sirius, and Betelgeuse form the Winter Triangle, which needs no further explanation.

This area is also the home of the Winter Hexagon formed by the stars Sirius, Procyon, Castor and Pollux, Capella, Aldebaran, Rigel and back to Sirius. It also contains nine of the 15 brightest stars visible from our latitude north. Observe the Winter Triangle from a dark location and you will see that the Winter Milky Way flows between Sirius and Procyon and just above Betelgeuse.

So whether you use your naked eye, binoculars or a small telescope, there’s much to enjoy up in the sky.

This month in history:

Feb 1: Shuttle Columbia breaks apart during reentry killing all 7 astronauts – 2003
Feb 7: First untethered spacewalk made by Bruce McCandless – 1984
Feb 14: Voyager 1 looks back to take photo of solar system – 1990
Feb 18: Pluto discovered – 1930
Feb 20: John Glenn is first American to orbit Earth – 1962
Feb 23: Light from supernova 1987a reaches Earth – 1987
Feb 24: Detection of first pulsar (by Jocelyn Bell in 1967) is announced – 1968

What’s Up in the Sky – January, 2021

Welcome Back Winter Constellations

Most people probably don’t consider January to be a time for going out and enjoying the wintry sky. After all, it’s usually cold and cloudy and often snowing. But on those rare occasions when the sky is clear, it is definitely worth the effort to step outside and enjoy the sights that the sky has to offer.

Part of the reason is because some of the year’s most beautiful and interesting constellations and stars are in view, conveniently located, and out at convenient times. Let’s start with Orion, the Hunter, one of the most easily recognizable patterns in the sky. As with most sky observing, timing is important, but not critical. If you go out tonight right after dark, it will be a challenge because Orion will just be rising low near the eastern horizon, and won’t be easily visible until about nine o’clock. As the month progresses though, it rises earlier until, by the end of the month, not only Orion, but also his friends will be dominating the southern sky.

Two patterns of stars stand out when viewing the Hunter – the four bright stars that form his torso and the three stars lined up to form his belt. Take this opportunity to scan the belt and sword with binoculars. See if you can tell which of the sword “stars” is not really a star at all, and which one appears to be a double star.

The two most famous and easily recognizable stars in Orion are Betelgeuse and Rigel, upper left and lower right of the four that make up his body. Betelgeuse is a red giant star that, if located where our Sun is, would extend out beyond Earth’s orbit. Rigel is a white giant 50 times bigger than the Sun. It will likely cool and expand and after tens of thousands of years until it too becomes a red giant.

Closer examination of the sword reveals that the middle “star” is actually the Great Orion Nebula, a complex and fascinating region of young, forming stars and glowing clouds of gas 20,000 times larger than our entire solar system. Embedded in the heart of the Great Nebula is the beautiful multiple star system known as the Trapezium, consisting of four hot young stars in a tight trapezoid-shaped cluster. Although the nebula itself is visible to the naked eye, you will need binoculars or a small telescope to see the Trapezium.

Just below the easternmost belt star lies a dark cloud of gas and dust silhouetted against a brighter region of glowing interstellar gas heated by the surrounding stars. Known as the Horsehead Nebula (it takes its name from its shape), its enormous size is almost beyond comprehension – you could fit a billion solar systems inside it. And the Horsehead is a tiny part of an even larger cloud that is only visible with the aid of large, specialized equipment. It is best seen by Googling online images.

So spend some time scanning Orion with binoculars and familiarizing yourself with this region of the sky. Next month I will guide you around Orion’s neighbors and visit nearby sights up in the sky.

This month in history:
Jan 1: Asteroid Ceres discovered by Giuseppe Piazzi – 1801
Jan 4: NASA cancels further production of Saturn V rockets – 1970
Jan 13: Galileo discovers Ganymede, moon of Jupiter – 1610
Jan 19: New Horizons spacecraft launched on its journey to Pluto – 2006
Jan 27: Apollo 1 astronauts Chaffee, White and Grissom die in fire in capsule – 1967
Jan 28: Seven astronauts killed when Space Shuttle Challenger explodes during launch – 1986

What’s Up in the Sky – December, 2020

Planets Put on a Great Show
Although I often write about things that end up being hidden by clouds, this month offers a very good chance to witness a very rare sight.

If your gaze has drifted toward the southwestern evening sky lately, you have hopefully noticed the scene I described at the end of last month’s column, Jupiter shining brightly with faint Saturn to its upper left. Since Jupiter is the brightest thing in the sky that’s not the Moon, you may have missed Saturn, which appears only one tenth as bright. Hold two fingers at arm’s length. That’s how far apart the two planets appear to be.

And that’s the key, their separation. They look pretty close now, but by December 21, they will be so close together that a pencil at arm’s length won’t fit between them. Their pairing is the closest since 1623 and until another in 2080. Unfortunately, no one saw the 1623 event because the Sun was in the way and in 2080 you’ll have to get up before sunrise to see them.

That’s another reason to make an effort to observe the two giants, you will probably never have another chance, although teenagers stand a chance of being able to say they saw it twice sixty years from now. So again, each clear day at six o’clock, check out the southwestern sky for the “stars” of the show.

For those with a small telescope or binoculars (preferably on a tripod) be sure to observe the planets as close to December 21 as possible. When the planets are at their closest, they should both be visible together in a single field of view in such devices. For those with a smart phone, zoom in on the scene to view it in real time. Take it all in and enjoy it because you probably will never have another opportunity.

In addition to that celestial show, this month also has a meteor shower to offer. The night of Sunday, December 13th could be called the night of the shooting stars for on that night you’ll have an opportunity to witness the most reliable, prolific, and brightest annual meteor shower, the Geminids (showers are named after the constellation from which they appear to streak).

Not long ago, August’s Perseids were considered the top shower. But over the past few decades, the Geminids have intensified and are now in first place. Their popularity is hampered by the lousy weather that usually accompanies them.

But if the 13th does turn out to be clear, find a dark spot facing east, bundle up more than you think is necessary, break out the summer recliner, take along a thermos and an extra blanket or insulated sleeping bag and enjoy what’s up in the sky.

This month in history:
Dec 3: Pioneer 10 spacecraft makes closest approach to Jupiter – 1973
Dec 4: Mars Pathfinder is launched – 1996
Dec 11: Annie Jump Cannon is born – 1863
Dec 14: Gene Cernan, Apollo 17 astronaut, is last human to walk on Moon – 1972
Dec 16: Last two Saturn V moon rockets donated to museums – 1976
Dec 24: Apollo 8 astronauts give us inspirational moment from lunar orbit – 1968
Dec 25: Isaac Newton born – 1642