Naked eye observing
The Phases of the Moon
It takes some thinking to understand and visualize how the phases of the moon work and where the sun and moon are relative to each other.
The Planets
Mercury, Venus, Mars and Jupiter can all be easily seen in the night sky. The planets all lie in the same plane, known as the elliptic, which is close to the plane that the Moon is in. If you see something you think is a planet but it is not near the elliptic, it’s not a planet.
Mercury and Venus are always close to the sun and so can only be seen near the horizon at sunrise and sunset.
Mars does have a reddish hue.
Jupiter is fairly bright.
Saturn was known to the ancients and can certainly be seen with the naked eye but it is more difficult.
Constellations & Asterisms
Asterisms are groups of stars that make a pattern but are not official constellations. I’m going to refer to them all as constellations. A few constellations are quite obvious and easily learned by children. These include:
- The Big Dipper
- The Little Dipper
- Orion
- Taurus
- Cassiopeia
- Scorpius
- Leo
- Canus Major
There are 88 officially recognized constellations which partition the sky into regions that make easier to locate objects in the sky. For instance, the Beehive Cluster is in the constellation Cancer.
Many of the constellations are only visible in the southern hemisphere. In addition, the constellations remain fixed in the sky, while the earth orbits the sun. So, sometimes the sun is between the earth and the constellation. Then the constellation is overhead during the daytime and is not visible. Therefore, constellations are often known as winter constellations (such as Orion) or summer constellations (such as Hercules) because those are the seasons when those constellations are overhead at night.
Meteor showers
There is no other way to appreciate meteor showers than with the naked eye. Because meteors appear randomly in the sky and disappear quickly, instruments are not helpful.
Although a meteor may appear sporadically at any time, there are certain times of the year when named meteor showers produce meteors frequently enough to specifically watch for them.
Artificial satellites
It is fairly easy to see an artificial satellite in the sky. Because they are only visible due to reflected light from the sun, you should look for them within a couple of hours of sunset (or sunrise). They will be hidden by earth’s shadow in the middle of the night. Satellites can be differentiated from airplanes because they move quickly and they don’t blink.
There are resources (Heavens-Above) that allow you to identify which satellite you saw, or to known when a good time to see a specific satellite, such as the International Space Station, is.
Satellite flares
Next to an eclipse, a satellite flare is one of the coolest things to see in the night sky. There are multiple satellites which have large reflective surfaces. As these satellites orbit, they can reflect a bright light onto the ground. When they do, they produce a light that quickly grows in intensity and then fades. There are resources (ONLINE 3D SATELLITE AND FLARE TRACKING ) that will help you determine where and when to see an satellite flare.
Eclipses
Total solar eclipses are the most amazing thing to see in the sky. Partial and annular eclipses are also impressive, although you must wear eclipse glasses for these. (No naked eye observing).
Lunar eclipses are much more frequent and last longer than solar eclipses. They are less impressive but still worth seeing from time to time.
Sunset and sunrise
Sunrise and sunset is so common that we sometimes forget to appreciate them, especially from an astronomical point of view. Many of the phenomena that we see are interactions between the sunlight and the atmosphere, such as:
- sun pillars
- sun dogs
- crepuscular rays
- the belt of Venus
It is also worth noting the multiple types of dawn or twilight, including:
- civil dawn (twilight)
- naval dawn (twilight)
- astronomical dawn (twilight)
Stars
These are some of the brightest stars in the night sky. It is important to recognize them to help orient you and to keep from confusing them with planets. Many of these have interesting scientific and/or historical stories related to them.
- The North Star
- Betelguese
- Rigel
- Vega, Deneb, Altair
- Aldebaran
- Sirius
- Arcturus
- Capella
The Milky Way
The Milky Way is often unnoticed due to light pollution and getting a good view of the Milky Way is an indication of a good night sky for viewing other celestial objects.
Aurora Borealis
The northern lights are not typically visible at our latitude. However, during a geomagnetic storm, the lights can sometimes be seen in the northern part of the sky. Often, great pictures of them can be taken with a 3 second exposure on a phone camera, which brings out more color than can be seen with the naked eye.
Zodiacal light
Stellarium with additions by Bob King
The zodiacal light is best seen from mid-northern latitudes at the end of dusk from late winter through early spring. This is when the ecliptic — which represents the plane of the solar system — is most steeply tilted upward from the western horizon just after sunset. The faint dust that comprises the zodiacal light cloud lies within the same plane and straddles the ecliptic. From late February through April, it stands head and shoulders above the horizon haze, greatly enhancing its visibility.
Occultation of a star by the moon
This is a rather rare event (or at least, rarely witnessed) in which the moon passes in front of a star. This is most impressive when the moon is only half-full and the star suddenly becomes visible as the dark half of the moon moves to uncover the star. There are resources that will give you exact times to be watching for this.
With Binoculars
The Moon
The craters of the moon can be appreciated with binoculars much better than with the naked eye. The best place to observe is the terminus, the dividing line between the sunlit part and the dark part of the moon. This is where the sunlight is hitting at an angle and the three dimensional structure can best be discerned.
Jupiter’s moons
Four of Jupiter’s moons can be seen through binoculars. You will see Jupiter surrounded by 4 tiny specks of light lying in a line on either side of Jupiter. Due to the motion of these moons, the location of those tiny specks will change over time. Sometimes you will not see all 4, since they may be hidden by Jupiter. These are the 4 moons that were seen by Galileo.
The Pleiades
The Pleiades is an open star cluster that is visible with the naked eye but you will see a lot more stars with binoculars.
Mizar and Alcor
These are two stars in the middle of the handle of the Big Dipper. To the naked eye, they are just barely discernible as two stars, but they are easy to distinguish with binoculars. These are optical binaries and not gravitationally interacting with each other.
The Orion Nebula
The middle “star” in the sword of Orion is actually a nebula, which is easy to see with binoculars. It is best seen in the winter.
The Beehive Cluster
This is one of the closest and largest open clusters in the night sky, located in the constellation Cancer.
The Double Cluster
The Double Cluster is two open clusters located close to each other in the constellation Perseus.
M13
M13 is a globular cluster in the constellation Hercules. It is best seen in the summer.
The Andromeda Galaxy
The Andromeda Galaxy can be seen with the naked eye but better appreciated with binoculars.
Comets
Comets are visible from time to time, usually for a few weeks at a time. Although a few are visible with the naked eye, many more are visible with binoculars. Often details such as the tail are visible.
The International Space Station
Although the ISS can be seen with the naked eye, you can make out some details with binoculars.
Resources
Interactive sky chart (heavens-above.com)
Related pages
- Astronomy hub
- Terms and concepts to know for astronomical observing
CoMo Science 
Leave a comment