Star Gazing Guide

May 22-28, 2020

Bare Dark Sky Observatory

Greetings Fellow StarGazers!

It’s hard to believe we’re closing in on summer. The nights are getting warmer, which makes for even more motivation to get outside under a star-filled night sky. The Bare Dark Sky Observatory is still six weeks away from re-opening, but our initial July 10 & 11 community evening events are filling up fast. While we usually allow a capacity of up to 25 people per event, we have opted to cap them at 20 for the time being. At that number we believe that we can safely adhere to the social distancing guidelines. Click HERE for access to BDSO tickets through Eventbrite.

What’s Up

Most seasoned amateur astronomers will tell you that May is kinda one of those transitional months. The planets aren’t coming into view until the wee hours, and the most fun deep sky objects require a telescope. However, a pair of binoculars and a comfortable lawn chair can definitely make for some memorable star and constellation hopping. Side note: Finding objects by “jumping off” nearby stars is called star hopping, and is a great way to learn the night sky without a computerized telescope. We suggest you keep your favorite night sky app or sky map close at hand. The good news is it looks like we’re in for a special treat …

Comet Swan Update

In last week’s Star Gazing Guide we mentioned the arrival of Comet Swan (pictured below) as it continues to make its visible journey into the northern hemisphere. Hopefully, several of you will make an effort to check it out. Our first best opportunity to see Comet Swan may be an hour after sundown beginning Monday, May 25 as it cruises through the Perseus constellation towards Auriga in the northwest sky. On May 27 Swan will reach its perihelion (closest point to our Sun – 40 million miles) and will supposedly reach its optimal brightness. If you miss seeing it in the early evenings, try catching it about an hour before sunrise in the north-northeast sky. Hopefully, you will see a nice green fireball with a long blue-green coma or tail of gas and dust. We would love to hear about any sightings and see any photos that you can share. As a heads up, comets are very unpredictable and Swan may deliver a surprise or two. In other words, it could brighten beyond expectations or quickly fizzle out on us. While telescopes and binoculars should provide easy viewing of Comet Swan, we’re hopeful for some rare magnitude 4 or 5 naked eye vistas. The last naked eye comet sighting in our area was Hale-Bopp back in 1997.

STAR CLUSTERS

One major class of deep sky objects is star clusters. Star clusters are basically groups of stars that come in two distinct types: openclusters and globularclusters.

Open Clusters are loose groups of several thousand stars or less. Many can be easily seen with the naked eye, like Pleiades (M45), and the Beehive (M44) (pictured below) in the constellation Cancer. Some are so easily seen that our BDSO guests will notice them before we even point them out. Those with telescopes usually find that viewing open star clusters with lower power eyepieces is preferable to higher power eyepieces because the wider field of view helps us see the most stars. Furthermore, binoculars help us more easily see the entire star cluster.

The stars in an open cluster are similar in age since they form out of the same stellar nursery within giant molecular clouds. So far, over a thousand open clusters have been discovered. One open star cluster (which is actually a constellation) you might want to check out with your binoculars is Coma Berenices, located next to Leo the Lion. The story behind Berenices is worth looking up since she was an actual Egyptian queen whose beautiful blond hair was sacrificially cut off to make good on a promise when her husband returned victorious from a war against Syria. Folklore has it that it was Berenices’s locks of hair that Zeus supposedly decided to display in the night sky for all time.

Globular Clusters are immense groups of stars tightly bound by gravitational attraction. Besides Saturn, Jupiter, Moon craters, and the Milky Way, viewing globular clusters is also a major crowd-pleaser at BDSO. Although several theories exist, the origin of globular clusters still remains a mystery. Many globular clusters can be spotted through binoculars, though very few with the naked eye. Since these clusters contain from ten thousand up to several million stars, without the magnification of a telescope most resemble blurry fuzz balls.

Our favorite, which is pictured below, the Hercules Great Globular (M13), is considered by many to be the most spectacular globular cluster visible in the northern hemisphere. It is only second in popularity to Omega Centauri, the largest globular cluster in the Milky Way which is only visible from the southern hemisphere. If you can find the Hercules constellation, either with a sky map app or otherwise, then M13 is pretty easy to locate. It sits about one-third of the way between two bright stars in the easily recognizable “keystone” trapezoid-shaped asterism, often referred to as Hercules’s head. Currently, M13 is in the top side of the keystone, but because everything moves over the course of the year it can be helpful to remember that M13 is always on the westernmost side.

As we close this edition, we leave you with this thought: Every star you gaze at in the night sky has incredible stories, mysteries, and histories to tell. As your eyes dance from one star’s point of light that left in 50 B.C. while Cleopatra sailed a moonlit Nile, to another star that winked at you from the 15^th century as Leonardo da Vinci was painting The Last Supper … remember to seize the moment with awe and wonder.

The renowned writer, Alan Moore, has suggested, “All we ever see of stars are their old photographs.” You think about that …

Keep Looking UP! 

Jeremy & Steve

BDSO Staff

website: mayland.edu/observatory

email: observatory@mayland.edu

Star Gazing Guide

May 15-21, 2020

Bare Dark Sky Observatory

Pictured: Heart Nebula. Photo Credit: Jeremy Bare

Greetings Fellow StarGazers!

If you want to enjoy the last views of our winter and spring night sky objects, you had better get outside early these next few evenings. With sunset around 8:30 pm, and civil twilight ending around 9:15, you can still catch Venus bright in the western sky before she says good-bye until next year. Also, Orion, Perseus, Andromeda, Cassiopeia, Taurus, and all the winter hexagon constellations are going down quickly until late autumn. That’s okay because we still have the Big & Little Dippers, Leo, Virgo, Bootes, Lyra, and several others to observe and enjoy.

Once upon a time, the comings and goings of our constellations were how farmers knew what crops to plant and when. While we no longer need to depend on those signs, we know that the arrival of certain constellations and planets earlier in the eastern night sky means summer and warmer weather are on the way. We have included the Evening Sky Map link below so you can check out what night sky objects are most easily viewed with the naked eye, binoculars, and telescope for May.

EVENING SKY MAP LINK

COMET SWAN

One highlight over the next few weeks will be Comet Swan as it graces our night sky. While Comet Atlas broke apart and didn’t quite live up to expectations, we’re fairly certain Swan is going to deliver an incredible show. Currently, Swan can be seen with the naked eye at around magnitude 5 rapidly moving into the pre-dawn eastern sky (through Pisces) of our southern latitudes (Florida). Reminder: magnitude refers to brightness. The lower the number, the brighter the object. Our naked eye sees magnitude 6 objects and under.

By May 21, Swan should hit a peak brightness of magnitude 2.8 and will become visible in our North Carolina pre-dawn sky. Through the rest of May until June 10 we should easily see (magnitude 5) Swan in the early evening northern sky as it moves toward Capella through Auriga. (See map below). Keep in mind that as Comet Swan moves towards our Sun, the solar wind will cause its tail to become brighter and longer and always pointing away from the Sun. Swan’s cape should present us with spectacular viewing, especially in binoculars and telescopes.

WHAT ARE NEBULAE?

First time viewers of a nebula through a telescope are often disappointed because they expect to see the incredibly colored nebulae that photography delivers. Instead, we generally see shades of white because our eyes are not as sensitive to color as cameras are. Nevertheless most astronomers will agree that nebulae are some of the coolest objects you can look at through a telescope. Nebula in Latin means “cloud” or “fog” and true to name it does often look rather like a “space cloud.” Unlike the clouds on Earth which are made of water vapor, nebulae are clouds of dust, hydrogen, helium, and other gases. Originally astronomers also referred to galaxies as nebulae before they realized the difference. The Andromeda Galaxy was once even called the Andromeda Nebula. Below are basic explanations of different types of nebulae.

Diffuse Nebula – These nebulae have no well defined boundaries. Some of them are “stellar nurseries” where the gas and dust of the nebula begins to clump together until it collapses under its own gravity and ignites forming a star. One of most photographed is the Orion Nebula (M42), which at magnitude 4 can be seen with the naked eye.

Planetary Nebula – These nebulae are formed when stars shed their outer layer leaving behind the core as a white dwarf star. The shed outer layer becomes a shell of gas around the star and radiation from the star causes a glow that allows us to see it. They form in many different shapes and some show significant amounts of color when viewed in a telescope. A BDSO favorite is the bluish colored Ring Nebula (M57) located in Lyra at about magnitude 9.

Supernova Remnant– When a particularly large star uses up the hydrogen fuel at its core, it reaches the end of its life and begins to collapse in on itself. The star’s gas can be heated by the collapse and rebound in a massive stellar explosion called a supernova. The scattered material from this explosion can form a particular type of nebula called a supernova remnant. At magnitude 8.4, the Crab Nebula (M1) was the first nebula to be recognized as a supernova remnant. In fact, the supernova that created it was recorded by Chinese astronomers in 1054. As often as we hear about the possibility of witnessing a supernova, such sightings are quite rare indeed.

The way that we see nebula is another way to classify nebula:

Emission – We see these nebulae because the gas inside it is excited by radiation causing it to glow and emit its own light; kind of like a neon sign.

Reflection – These nebulae have stars inside that are illuminating the surrounding gas and dust which get reflected, allowing us to see them.

Dark – We can’t actually see these nebulae directly. But we can tell they are there because they block our view of something behind it. The biggest dark nebulae are quite prominent and can be seen with your naked eye as when you look at the Milky Way on a clear night. The huge darker patches are where dark nebulae are blocking our view of some of the stars. The two main ones are called the Great Rift and the Coalsack Nebula.

As we close this edition, we want to thank those of you who have sent us words of encouragement and affirmation. We especially love hearing your stories of stargazing with family and friends. Definitely let us know if there is a particular astronomy subject you would like us to cover. We’ll do our best!

Quite often we are asked, “Do you think there is intelligent life out there?” We like Arthur C. Clark’s answer: “Two possibilities exist: Either we are alone in the Universe, or we are not. Both are equally terrifying!”

Keep Looking UP! 

Jeremy & Steve

BDSO Staff

website: mayland.edu/observatory

email: observatory@mayland.edu