Telescope Night Information

Possible Telescope Targets

The Ring Nebula (M57)

The Ring Nebula as seen in infrared light by the James Webb Space Telescope. In the eyepiece it will appear as a grey smoky ring and is best observed with peripheral vision (a.k.a using averted vision). Credit: ESA/Webb, NASA, CSA, M. Barlow, N. Cox, R. Wesson
The Ring Nebula (M57) is a huge tubular cloud composed mostly hydrogen and helium that once constituted the outer layers of a Sun-like star that died thousands of years ago. The star at the center of the nebula, which is responsible for illuminating the gas, is the core of the original star that will continue to cool over billions of years. This nebula, which is located about 2,300 light-years from Earth in the constellation Lyra, is known as a planetary nebula. This name is a misnomer – planetary nebulae have nothing to do with planets other than the more distant nebulae tend to look small and round, much like planets. Planetary nebulae are created when a smaller star runs out of fuel at its core, swells to become a red giant, and ejects its outer layers into space over thousands of years. This is the fate of our own Sun in roughly five billion years. The Ring Nebula is conveniently located almost directly in the middle of two bright stars of the parallelogram of the constellation Lyra, Sheliak and Sulafat, making it an easy target to find for anyone.
The Cat's Eye Nebula (NGC 6543)

The Cat's Eye Nebula as seen with Dyer Observatory's Seyfert Telescope. Credit: Billy Teets
Found among the snaking body of the constellation Draco, the Cat’s Eye Nebula, formally known as NGC 6543, is a grand example of a planetary nebula. Despite the name, this type of object has nothing to do with planets except for a somewhat similar appearance to some of the planets in a telescope. What we’re are actually seeing is the remains of a small star that has met its demise. Though many mistakenly believe that all stars explode when they expire, the majority of stars are too small to undergo supernova explosions in their final moments. Most stars, including our own Sun in five billion years, will go through a couple of stages of swelling to many times
their original size. At this point, the outer layers of the star are very weakly held by the gravity of the collapsing core and are gently lost to space over thousands of years. During this process, the white-hot core, known as a white dwarf, is exposed to space. The copious ultraviolet light emitted by the small core is absorbed by the expanding outer layers, causing them to fluoresce like a cosmic neon sign. The white dwarf, seen at the center of the nebula, is the size of our planet, but a spoonful of it on Earth would weigh as much as an elephant!
M13 - The Great Hercules Cluster

The Great Cluster in Hercules contains around 300,000 stars and is the farthest object visible to the unaided eye that is also part of the Milky Way. Credit: Martin Pugh
The Great Cluster in Hercules, also known as Messier 13 or M13, is one of 150 or so known globular clusters that mostly orbit the Milky Way. This cluster is densely packed with about 300,000 stars in a sphere 150 light-years wide. By comparison, there is less than one percent of this number of stars surrounding our Sun in the sphere of the same size. At an age of more than 10 billion years, globular clusters like M13 are some of the oldest objects known. When astronomers mapped the locations of globular clusters on the sky and incorporated their distances to determine their physical locations in space, they found that the clusters had a fairly spherical distribution and that our solar system was offset from the center of that sphere. It was deduced that the distribution’s center coincided with the center of the Milky Way galaxy, which gave us one of our first estimates of how far we were located from the center of our home galaxy. On a clear, dark night, M13 is visible without a telescope, appearing as a fuzzy star in the “keystone” of Hercules. At 25,000 light-years distant, it is the farthest object associated with the Milky Way that one can see with the unaided eye.
The Double Double

Epsilon Lyrae, also known as the "Double Double," appears as a single star to the naked eye and as a pair of stars in binoculars or small telescope. Medium size telescopes will reveal that each star is actually a pair of stars. Credit: Julian Zoller
Appearing as a single star by eye and a pair of stars with binoculars or low-magnification telescopes, Epsilon Lyrae is a multiple-star system that lies just to the north of the bright star Vega in the constellation Lyra. The system is better known as the “Double Double” because high-magnification reveals that each of the two stars (ε1 and ε2) is in fact a pair of stars. One pair takes nearly two millennia to complete one orbit while the other pair takes a mere 720 years to complete an orbit. The stars of each pair are separated by about 120 astronomical units (about four times the Sun-Neptune distance). The pairs’ apparent angular separation and known distance of approximately 160 light-years from Earth mean the duos are separated by roughly 0.16 light-years. Even at this great distance, they are gravitationally bound to one another, completing an orbit in the span of hundreds of thousands of years.

Key Points of Interest

The map below will provide locations for key points of interest in the observatory. If you have any questions, please don't hesitate to ask a staff member or volunteer.

Garland Collection - Many of the original astronomy instruments obtained by Chancellor Landon Garland in the 1870s for use in the first physics and astronomy classes of Vanderbilt University.
Star Model - An interactive model that displays information and positions of the 100 nearest and 100 brightest stars in the night sky as well as information about our own star, the Sun.
Fused-Quartz Mirror Disk - One of two original, uncoated test mirrors for the 200" Mount Palomar Observatory that were given to Vanderbilt University. One was originally intended to be used in a new telescope of Vanderbilt University.
Seyfert Telescope - On clear nights, the 24" Seyfert Telescope will be viewing a selected target. On cloudy nights, the doors will be open for visitors to see and learn about Dyer's largest telescope.
Hallway Images - Large infographics about galaxies, the Milky Way, and the life cycles of stars. On the opposite wall is a high-resolution panorama of the Milky Way with constellations and deep-sky objects highlighted.
HST Model & Planetarium Dome - Learn about the Hubble Space Telescope with the 1/5th scale model suspended in Dyer Observatory's original planetarium dome and experience the dome's acoustics.
AstroCantus - A combination of art and science, AstroCantus is a series of chimes that sound as the stars pass overhead. NOTE: The chimes may be muted - ask a volunteer.
ViewSpace Presentation - A presentation from the Space Telescope Science Institute. The program consists of continuous presentations ranging in length from five to 20 minutes and covering a variety of topics. Visitors may come and go as they please during the presentation.
Meteorites & Tektites - A collection of various types of meteorites and tektites.

Sky Chart for May 9, 2025

To use this sky chart, hold it up to the sky so that the direction labels are aligned with the cardinal directions. If you want to see what is in one particular direction, hold the chart out in front of you and rotate it so the label for the direction you are facing is at the bottom. For example, if you are looking north, then you will turn this chart upside down so that the “N” is at the bottom of the page.

The sky shown in the chart is what one would observe at the following dates and times:

June 5th – 11:00PM CDT
June 20th – 10:00PM CDT (The Moon/planets are shown for this date)
July 5th – 9:00PM CDT

Deep Sky Objects

The objects listed in red are some of the brighter deep sky objects – objects that are outside of our solar system and aren’t single stars. These are just a few of the 109 Messier objects – bright “fuzzy” objects that Charles Messier noted positions of as he was scanning the sky for comets during the late 1700s and early 1800s. The 109 objects, each of which has a number preceded by a capital “M,” consist of star clusters, different types of nebulae (emission, planetary, and supernova remnants), and galaxies. These are among the brightest and most easily observed objects by both amateur and professional astronomers.

Stars and Constellations

This sky chart only shows a couple hundred stars that are visible to the unaided eye under dark conditions. Some of the brightest stars have their names shown in bold. Many others have names that were given to them by ancient astronomers, while others simply carry a catalog name/number. The apparent size of the dot representing a star tells you about its brightness – the brighter the star, the larger the dot. Sirius is the brightest star in the night sky.

The fall-winter sky contains a number of famous constellations that are visible from Tennessee. Many, such as Orion, Taurus, and Gemini, have Greek mythologies behind them. To the south are some not-so-familiar constellations, such as Antlia and Pyxis, which represent an air pump and mariner’s compass, respectively. In all, 15 of the southern constellations that are recognized by the International Astronomical Union (IAU) were established by French astronomer Nicolas-Louis de Lacaille during his expedition to the Cape of Good Hope in 1750.

General Information About the Sky

The ecliptic is the imaginary line that the Sun follows through our sky. In reality, this line is dictated by the orbit of the Earth. Since all of the planets of the solar system lie in nearly the same plane, one will observe the planets positioned very close to or on this line as well. Because the Moon’s orbit is tilted just a bit more than five degrees to this line, the Moon will not stray far from the ecliptic either. Some objects, such as comets, will not stay around the ecliptic. The constellations through which the ecliptic passes are the 12 famous zodiac constellations. There are, however, 13 constellations through which the Sun passes. For the first two weeks of December, the Sun is located in the constellation Ophiuchus, the serpent bearer.

There are 88 official constellations that cover the entire sky. Some are never visible from Tennessee as we are too far north; however, some, such as Ursa Minor and Camelopardalis, are circumpolar – they never get low enough in the sky to disappear below our horizon. The rest of the constellations are seasonal and visible in the evening sky for certain months of the year. Constellations are not just the stick figures we sometimes imagine connecting the brighter stars but are instead entire areas of the sky – everything is in a constellation. Objects outside of our solar system (stars, nebula, clusters, galaxies) remain in constellations, but the Moon, Sun, planets, comets, and asteroids all move through the constellations over time. Some famous star formations, such as the Big Dipper, Little Dipper, and Great Square of Pegasus, are not constellations – they are very recognizable parts of constellations known as asterisms. The Big Dipper, for example, is just a part of the constellation Ursa Major, the great bear.

Our Sun is just one of about 300 billion stars that make up our home galaxy, the Milky Way (shown in light grey in the sky map). In the late evenings of winter and summer, the Milky Way can be seen overhead. In the late summer, we are looking towards the center of the galaxy, which appears somewhat brighter. In the late winter, we are looking away from the center. Our solar system is situated on its side about halfway out from the center of this barred spiral galaxy.

When the Milky Way is easily visible, we have an opportunity to see many examples of the different types of objects found in the disk of a spiral galaxy. Spiral galaxies contain large amounts of dust and gas from which stars can form. As these clouds of material, known as nebulae, begin to collapse, denser pockets within the nebulae collapse faster to produce stars. When the stars begin to shine, they illuminate the clouds from which they formed. A prime example for late autumn to early spring is the Great Orion Nebula (M42), which forms the second “star” in the sword of Orion, the hunter. As time goes on and star formation uses up the remaining material of a nebula or disperses it, all that will eventually remain is a cluster of a few hundred to several thousand stars. These clusters, known as open clusters, are dominated by hot, blue-white stars and highlight the spiral arms of galaxies like our own. The Pleiades Cluster (M45), also known as “Subaru” or the “Seven Sisters,” is a beautiful example of such a cluster. The proximity of the cluster makes about six of its members easily visible to the unaided eye, but a low-power telescope will show dozens more.

The more massive a star is, the shorter its life will be. Massive stars therefore do not have enough time to venture far from the disk of the galaxy before ending their lives in spectacular supernovae. One such star, which was observed to explode in 1054 A.D., formed the Crab Nebula (M1). Most stars, however, are not massive enough to die explosively; instead, they puff up to become red giants and then gradually shed their outer layers over thousands of years. Once the core of the dying star is exposed, its ultraviolet light causes the shed layers to fluoresce, producing a beautiful planetary nebula. These nebulae have nothing to do with planets, rather their shape sometimes resembles the outer planets. Excellent examples of planetary nebulae are the Ring Nebula (M57), Clown Nebula (NGC 2392), and Cat’s Eye Nebula (NGC 6543).

During the late spring and autumn, the Milky Way appears closer to the horizon. Our galaxy, like all spiral galaxies, is shaped like a disk and is fairly thin compared to its width. As a result, when we see the Milky Way near the horizon, we are able to look up and out of our galaxy relatively easily to see objects outside of it. These include other spiral galaxies, like the Whirlpool (M51) and Andromeda (M31) galaxies, and spherical- to football-shaped galaxies known as elliptical galaxies, such as M87. Orbiting around these galaxies are globular clusters such as the Hercules Cluster (M13) and the Pegasus Cluster (M15). These clusters contain anywhere from a few hundred thousand to over a million stars in a small volume.