Kitt Peak Nightly Observing Program
Splendors of the Universe on YOUR Night!
Many pictures are links to larger versions.
Click here for the “Best images of the OTOP” Gallery and more information.
The Big Dipper (also known as the Plough) is an asterism consisting of the seven brightest stars of the constellation Ursa Major. Four define a “bowl” or “body” and three define a “handle” or “head”. It is recognized as a distinct grouping in many cultures. The North Star (Polaris), the current northern pole star and the tip of the handle of the Little Dipper, can be located by extending an imaginary line from Big Dipper star Merak (β) through Dubhe (α). This makes it useful in celestial navigation.
The Engagement Ring: Through binoculars, the North Star (Polaris) seems to be the brightest on a small ring of stars. Not a constellation or cluster, this asterism looks like a diamond engagement ring on which Polaris shines brightly as the diamond.
Constellation Ursa Minor is colloquially known in the US as the Little Dipper, because its seven brightest stars seem to form the shape of a dipper (ladle or scoop). The star at the end of the dipper handle is Polaris, the North Star. Polaris can also be found by following a line through two stars in Ursa Major—Alpha and Beta Ursae Majoris—that form the end of the ‘bowl’ of the Big Dipper, for 30 degrees (three upright fists at arms’ length) across the night sky.
Auriga is located north of the celestial equator. Its name is the Latin word for “charioteer”, associating it with various mythological charioteers, including Erichthonius and Myrtilus. Auriga is most prominent in the northern Hemisphere winter sky, along with the five other constellations that have stars in the Winter Hexagon asterism. Auriga is half the size of the largest constellation, Hydra. Its brightest star, Capella, is an unusual multiple star system among the brightest stars in the night sky. Because of its position near the winter Milky Way, Auriga has many bright open clusters within its borders, including M36, M37, and M38. In addition, it has one prominent nebula, the Flaming Star Nebula, associated with the variable star AE Aurigae.
Boötes has a funny name. Pronounced boh-OH-deez, this constellation’s name means sheepherder, or herdsman. It looks kind of like a kite, or a shoe. Some remember that “Boötes look like a boot” to help pick it out in the sky.
Cancer is one of the zodiac constellations, which means the ecliptic—or plane of the Solar System, runs through it. The Sun, Moon, and planets move along the ecliptic, and therefore, you can sometimes find these Solar System objects in Cancer. Cancer is a medium-sized medium-brightness constellation, located between Gemini and Leo along the ecliptic. You can find the notable open star cluster Beehive cluster (also known as M44 or Praesepe) within Cancer. In greek mythology, cancer was a crab that, under the instruction of Hera, latched onto Hercules’s feet while he was battling Hydra. Hercules and Hydra are also constellations, and Hydra borders Cancer.
Canis Major, the “big dog”, boasts the brightest star in the night sky—Sirius! Also known as The Dog Star because of the constellation it resides in, Sirius is a massive, hot, blue star—and it’s right next door! One of the reasons Sirius is so bright is that it is so close to us—only 8.6 light-years away. It’s name comes from Greek, and means “glowing” or “scorcher”.
Cassiopeia is widely recognized by its characteristic W shape, though it may look like an M, a 3, or a Σ depending on its orientation in the sky, and your position on Earth. However it’s oriented, once you’ve come to know its distinctive zig-zag pattern, you’ll spot it with ease. The plane of the Milky Way runs right through Cassiopeia, so it’s full of deep sky objects—in particular, a lot of open star clusters. Cassiopeia is named for the queen form Greek mythology who angered the sea god Poseidon when she boasted that her daughter Andromeda was more beautiful than his sea nymphs.
Draco the dragon lies close to the North polar point of the celestial sphere. Thus, it is best viewed from north of the equator. This celestial dragon has a long serpentine shape that winds around the constellation Ursa Minor (better known by the name Little Dipper), which is far fainter than it’s companion, Ursa Major. The tail of Draco separates these two constellations.
Gemini is a well known zodiac constellation. Zodiac constellations line up with the plane of the Solar System in our sky, an intersection known as the ecliptic. This means you will find planets passing through Gemini from time to time. Gemini is also grazed by the plane of the Milky Way, and therefore has a few deep sky objects within its boundaries. Gemini’s brightest stars get their names from twins Castor and Pollux of Greek mythology.
Hercules is named for the famous hero of Greek mythology by the same name. It’s one of the larger constellations, but its stars are of only moderate brightness. The Keystone is a well known trapezoid-shaped asterism (association of stars that are not an official constellation) within Hercules. This constellation is host to M13 (Messier 13), a globular star cluster. Otherwise known as the Hercules Globular Cluster, M13 is home to 300,000 stars, and is just over 22,000 light-years away.
Leo is a fairly well known constellation, because the plane of the Solar System runs through it. Such constellations are called Zodiac Constellations. Leo has some notable, bright stars, in it to boot. The brightest of these, Regulus is at the bottom of a series of stars arrayed in the form of a sickle, or a backwards question mark. This constellation does look more or less like the side profile of a lion lying on the ground, with its head up.
Orion is a famous constellation, well known especially for the Belt of Orion—three stars in a line at what seems to be the waste of a human figure. The bright stars Rigel and Betelgeuse are two of the brightest stars in the sky. Between the Belt and Rigel you can see the Orion Nebula—the closest star forming region to our Solar System. A beautiful object in a telescope or binoculars, you can also just make out the nebula naked-eye.
You can look to Taurus, the bull, to find the two closest open star clusters to our Solar System. The Pleiades (or, Seven Sisters) is the second closest at 444 light-years away. It’s an obvious cluster to even the naked eye. The Pleiades is named for the seven daughters of Atlas and Pleione of Greek Mythology. To the left of the pleiades, the Hyades (siblings to the Pleiades in mythology) is the closest open star cluster to Earth at 153 light-years away. The Hyades has a characteristic V shape to help identify it.
Ursa Major, or, the Big Bear, is one of the best known and most well recognized constellations, but you might know it by a different name. Contained within the boundaries of the constellation Ursa Major is the Big Dipper, which is not a true constellation, but an asterism. The Big Dipper is useful for finding both the North Star and the bright star Arcturus. Follow the curve of the handle to “arc to Arcturus” and use to two stars in the dipper opposite the handle to point to the North Star.
Ursa Minor, the Little Bear, is much fainter than it’s companion the Big Bear, Ursa Major. Within Ursa Minor is the well known asterism The Little Dipper. The end of the tail of the bear, or the end of the handle of the dipper, is a star called Polaris—the Pole Star, or the North Star. This special star happens to sit at the point where the Earth’s axis of rotation intersects the sky
Virgo’s brightest star Spica is found by following the curve of the handle of the Big Dipper (“arc to Arcturus, in Boötes, then spike to Spica”).The rest of the constellation isn’t particularly bright, but Virgo lies along the ecliptic—the plane of the Solar System, so bright planets pass through occasionally.
M13 Hercules Globular
M13, the “Great Globular Cluster in Hercules” was first discovered by Edmund Halley in 1714, and later catalogued by Charles Messier in 1764. It contains 300,000 stars, and is 22,000 light-years away. Light would need over a century to traverse its diameter.
The ecliptic is a path in the sky, forming a great circle around the Earth, which the Sun and other planets of the Solar System move along. It is formed where the plane of the Solar System intersects with the Earth’s sky.
Human technology! There are almost 500 of these in Low Earth Orbit (we can’t see the higher ones). We see these little “moving stars” because they reflect sunlight.
The twinkling of star light is a beautiful effect of the Earth’s atmosphere. As light passes through our atmosphere, its path is deviated (refracted) multiple times before reaching the ground. Stars that are near to the horizon will scintillate much more than stars high overhead since you are looking through more air (often the refracted light will display individual colors). In space, stars would not twinkle at all. Astronomers would like it if they could control the effects of this troubling twinkle.
The Green Flash
What we call “The Green Flash” is not so much a flash as a flicker of green color, seen on the top of the sun as it sets (or rises). This rare event needs just the right atmospheric conditions.
The “Double Cluster” (NGC 884 and NGC 869) is a pair of two open star clusters that are a treat for binoculars and telescopes alike. Each is a congregation of many hundreds of stars, around 50-60 light-years in diameter. These clusters are both about 7,500 light-years away.
M37 Salt & Pepper Cluster
M37, the “Salt and Pepper Cluster” is one of three bright open star clusters in the constellation Auriga. It is the brightest and richest of the three. It lies about 4,500 light-years away, contains about 150 stars, has a diameter of about 25 light-years, and is 450 million years old.
M41 is an open star cluster located just below the brightest star in the night sky, Sirius. It contains about 150 stars spread out over 25 light-years, and is 2,300 light-years away.
M44 The Beehive
M44, the “Beehive Cluster,” and also known as “Praesepe,” is a large, bright, diffuse open star cluster containing about 400 stars. It lies fairly close, at a distance of under 600 light-years.
Jupiter is the largest planet in the Solar System, a “gas giant” 11 Earth-diameters across. Its atmosphere contains the Great Red Spot, a long-lived storm 2-3 times the size of the Earth. The 4 large Galilean satellites and at least 63 smaller moons orbit Jupiter.
The same side of the Moon always faces Earth because the lunar periods of rotation and revolution are the same. The surface of the moon is covered with impact craters and lava-filled basins. The Moon is about a fourth of Earth’s diameter and is about 30 Earth-diameters away.
Castor (α Gem)
Castor (α Geminorum) is a multiple star in the constellation Gemini, the twins. Through the telescope, a close pair of bright white stars and a more distant red dwarf companion are visible, but these are each spectroscopic binaries, making Castor a six-star system. Castor is about 50 light-years away. The bright components orbit each other with a period of about 450 years.
2.1 Meter Telescope and Robo-AO
The 2.1 Meter telescope has an 84″ primary mirror made of Pyrex, that weighs 3,000 lbs. The telescope became operational in 1964—one of the first operational reserach telescopes on the mountain. As part of the National Optical Astronomy Observatory (NOAO) for many decades, it is an important part of the history of the mountain, and has made many important contributions to astronomical research. Despite its significant role within the National Observatory, by 2015 the time came to pass the telescope on to new tenants, so NOAO could focus its efforts on its newer, more advanced telescopes. The Robo-AO team stepped in, and installed their state-of-the-art robotic adaptive optics system on the 2.1 Meter. Adaptive optics allows telescopes to nearly eliminate the distorting effects of the atmosphere, greatly increasing the resolution of the telescope. Thanks to its new tenants, suite of instruments, and the dark skies of Kitt Peak, the 2.1-meter continues to make important contributions to astronomical research.
Mayall 4 Meter Telescope
The Mayall 4 Meter Telescope was, at the time it was built, one of the largest telescopes in the world. Today, its mirror—which weighs 15 tons—is relatively small next to the mirrors of the world’s largest telescopes. Completed in the mid-’70s, the telescope is housed in an 18-story tall dome, which is designed to withstand hurricane force winds. A blue equatorial horseshoe mount helps the telescope point and track the sky. A new instrument called DESI (Dark Energy Spectroscopic Instrument) will soon be installed on the 4-meter. Once installed, DESI will take spectra of millions of the most distant galaxies and quasars, which astronomers will use to study the effect of dark energy on the expansion of the universe.
The Mayall 4 Meter is named for Nicholas U. Mayall, a former director of Kitt Peak National Observatory who oversaw the building of the telescope.
McMath-Pierce Solar Telescope
The Mc Math Pierce Solar Telescope is actually 3 telescopes-in-one. It was, at the time of its completion in the 1960s, the largest solar telescope in the world. It will remain the largest until the completion of the Daniel K. Inouye Solar Telescope (DKIST) in 2018. The Solar Telescope building looks like a large number 7 rotated onto its side. The vertical tower holds up 3 flat mirrors, which reflect sunlight down the diagonal shaft—a tunnel which extends 200 feet to the ground, and another 300 feet below ground, into the mountain. At the bottom of this tunnel are the three curved primary mirrors, which reflect the light of the Sun back up to about ground level, where the Sun comes into focus in the observing room.
Your Telescope Operator and Guide. Thank you for joining me this evening! See you soon!!
The web page for the program in which you just participated is at
Nightly Observing Program. Most of the above images were taken as
the Overnight Telescope Observing Program. For more information on this unique experience please visit Overnight Telescope Observing Program.
Copyright © 2018 Kitt Peak Visitor Center