The Summer Night Sky

It’s summer. It’s hot and it gets dark late, but there are still some wonderful objects to view in the night sky this time of year. Here are some notes adapted from two earlier FAS Astronomer Blogs.

The Night Sky

In the Summer, look for Scorpius the Scorpion, with its orange heart Antares. Scorpius really does look like a scorpion. Folks living in Hawaii can see Scorpius, but they don’t have scorpions. They see it as a big fish hook. Have you heard of Maui’s hook?

Scorpius is followed by Sagittarius the Archer low in the horizon. Note the “teapot” shape of Sagittarius.

Higher in the sky and to the east is the Summer Triangle consisting of Altair (Aquila the Eagle), Vega (Lyra the Harp) and Deneb (the tail of Cygnus the Swan). Find the yellow/blue “double star” Albireo at the head of the Swan.

Hercules is visible in the summer when looking south. It is, however, from this vantage point it, upside down. Draw a line from the center star of Cygnus (wings and body) through Vega to Hercules. Find the Keystone with four stars representing his body and the Hercules Globular Cluster (M13) on the far side of the keystone from Vega. Hercules is upside down and is kneeling with his other foot on the head of Draco the Dragon.

Turn around toward the north and find the Big Dipper to the east (left). Follow the two stars at the end of the bowl to find Polaris (the North Star) at the end of the tail of the Little Dipper. Notice that the Little Dipper is always found curved in toward the Big Dipper. You might see the queen Cassiopeia off to the west (right) looking like a big W or M. Nearby is the faint King Cepheus resembling a child’s drawing of a house.

Between the Big and Little Dippers is the tail of the dragon, Draco. Draco is a long winding constellation. It body stretches through the northern sky until you find his head under the foot of Hercules. When viewed from the north, Hercules is right side up.

See our webpage about The Night Sky for a few suggested smart phone and tablet apps and links to various star maps including Stellarium Web. The Astronomical League has monthly sky charts (see below). You might also visit the new Kaleideum Digital Dome Planetarium for their sky tours (general museum admission rates apply).

The Deep Sky

There are several objects in and around Scorpius and Sagittarius (aka the “teapot”). To find them use these stars.

  • Shaula/Lambda Scorpii, the Scorpion’s “stinger”.
  • Kaus Media/Delta Sagittarii, the upper right corner of the teapot.
  • Phi Sagittarii, the upper left corner of the teapot.
  • Nunki/Sigma Sagittarii, the top outside of Sagittarius’ handle.
  • Kaus Borealis/Lambda Sagittarii, the tip of the teapot’s lid.
  • Alnasi/Gamma Sagittarii, the tip of the “spout” of the Sagittarius teapot”.

The Ptolemy Cluster [M7] is between the constellations Scorpius and Sagittarius. It is around ½ way between Shaula and Alnasi. The Butterfly Cluster [M6] is close by The Ptolemy Cluster. Draw a line from Nunki to Kaus Media. Extend it out the same distance and just below Alnasi toward Scorpius.

The Lagoon Nebula [M8] is to the right and above the teapot lid. Draw a line from Nunki to Kaus Borealis and extend it out about the same distance to the nebula. The Trifid Nebula [M20] is just above the Lagoon Nebula. To find it, draw a line from Kaus Media through the Lagoon Nebula and extend it just a bit further and slightly to the left.

Well above Kaus Borealis is an open cluster [M25], the Swan/Omega Nebula [M17] and the Eagle Nebula [M16]. Draw a vertical line perpendicular to the base of the teapot and Phi Sagittarius. Extend it around two times to M25, three times to the Omega Nebula, and 3 ½ times to the Eagle Nebula. Look for the Pillars of Creation near the center of the Eagle Nebula.

A globular cluster [M22] is found to the left of Kaus Borealis and above Phi Sagittarii. A smaller globular cluster [M28] is found above and just to the right of the Kaus Borealis.

The Ring Nebula [M57] is a planetary nebula found between Sulafat/Gamma Lyrae and Sheliak/Beta Lyrae (the two bottom stars of Lyra the Lyre/Harp). Despite its low magnitude, it can be found with a small telescope.

The Dumbbell Nebula [M27] is a planetary nebula resembling a dumbbell found in the constellation Vulpecula. This constellation is very difficult to find, so draw a line from Rotanev/Beta Delphini (right star of the Daphnis “diamond”) toward Albireo (the head of Cygnus). The nebula is just over ½ way between the two. It is also just above and ¼ of the way on a line from Eta Sagittae (the point of Sagitta’s arrow) toward Albireo.

The Wild Duck Cluster [M11] is an open cluster Shaped like a V (flock of ducks). This one might also be challenging to find. It is technically found in the constellation Scutum but use Aquila to find it. Draw a line from Altair to Delta Aquilae (what might be considered the bottom of a diamond forming Aquila). Extend the line around 1 ¼ times farther to the cluster. It is down and just to the right of Lambda Aquilae (the end of Aquila’s tail).

The Cooling Tower Cluster [M29] (not shown in the diagram below) is just off to the right of Sadr and near the right wing of Cygnus. Follow the right wing for a very short distance and then slightly forward toward Albireo.

Three more difficult objects (not shown on the diagram below) can be found around the constellation Cygnus.

  • Not too far from the star Deneb is the North American Nebula [C20 / NGC 7000] with the distinct Cygnus Wall.
  • Between the North American Nebula and Deneb and slightly toward Albireo is the Pelican Nebula [IC 5070].
  • Near the right wing of Cygnus is the Eastern Veil Nebula [C33 / NGC 6992] and Western Veil Nebula [C34 / NGC 6960].
  • Near the star Sadr at the center of the Northern Cross and toward Albireo is the Crescent Nebula [C27 / NGC 6888].

Another one of my favorite objects is the Hercules Globular Cluster [M13]. This is the brightest globular cluster visible from the Northern Hemisphere. It is found on the side of the Hercules Keystone facing away from Vega and toward Arcturus and Corona Borealis. It is approximately 1/3 of the way from Eta Herculis (the corner of the Keystone near his “kneeling leg”) and toward Zeta Herculis A (Hercules’ upper left shoulder and the lower right corner of the Keystone).

There is another globular cluster [M92] found in the constellation Hercules. It is located approximately ½ of the way between the top middle of the keystone (between Pi Herculis and Eta Herculis) and Iota Herculis (near the head of Draco).

For these directions, we assume Hercules is upside down as it appears when viewing it looking south.

A Few References

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