5 Types of Night Sky Objects
Have you ever marveled at the night sky and wondered how insignificant we are in the grand scheme of things? We are just dots in this massive Earth and our planet itself is a dot in the solar system. Our solar system is a dot in the Milky Way Galaxy and there are billions of such galaxies in the universe.
We can see only a tiny portion of this universe with our naked eye or telescopes. This is an attempt to classify and make sense of all the objects that we see in night sky.
The 5 Types of Night Sky Objects
1. Solar system planets and moons
3. Meteor showers and fireballs
4. Stars and constellations
5. Deep Sky Objects
1. Solar System Planets and Moons
There are 8 planets in our solar system since Pluto is no longer considered a planet. Out of these, we can see 5 planets with our naked eye. The five naked-eye planets are Mercury, Venus, Mars, Jupiter and Saturn. Uranus and Neptune can be viewed with the help of powerful telescopes only if you know where to look.
Mercury and Venus
I have seen all the 5 planets with naked eye. I am yet to spot Uranus and Neptune. Mercury and Venus are called inferior planets in relation to earth. Their orbits are closer to sun than that of our Earth. Because of this reason, these two planets would always stay closer to Sun. These two planets could be seen either in the west after sunset or in the east before sunrise when they are visible.
Venus has phases similar to Moon and one should attempt to watch the crescent Venus through a telescope. Mercury is a difficult planet to spot for city dwellers as it is visible only for a few weeks in a year. But it can be bright and is easy to spot. We get our best chance to spot Mercury on 15th December 2018 as it rises an hour before sunrise. As a bonus, we can also see the bright Venus whose crescent is visible when viewed through a small telescope.
Jupiter, Mars and Saturn
Jupiter is the second brightest planet in the night sky and the fourth brightest object overall. A small telescope can help one see Jupiter's four moons. Mars is called the red planet because of its red tinge. Saturn is another bright planet visible to naked eye. A medium or large telescope is needed to view the famous rings of Saturn.
It has been my wish to spot a comet from my childhood. During my school days, there was a buzz that the Haley's comet would appear in night sky. I knew it was my last chance to spot as it has a periodicity of 76 years. I stayed awake for several nights to glimpse this periodic comet but I failed. It is possible I did not know where and when to look.
In 2013, there was too much hype around comet ISON as it was predicted to become the comet of the century. But it fizzled out and I could not have a glimpse of the same. The comet was predicted to become as bright as Full Moon but that did not happen as the comet disintegrated during its close encounter with Sun.
Comet C/2014 Q2 Lovejoy
In Jan 2015, I was lucky enough to spot Comet C/2014 Q2 Lovejoy using my modest pair of binoculars from my home. It was not bright, but it was still a special moment for me as this was my first observation of a comet.
3. Meteor Showers and Fireballs
Shooting stars are streaks of light we see once a while across the night sky. I am fortunate to have seen many shooting stars in night sky. Most of this have happened several decades ago during my childhood.
Meteor showers represent the specific periods in a calendar year when the meteor activity peaks. This is when our planet crosses the path taken by comets and the debris left behind by the comets impact our atmosphere as shooting stars. These shooting stars are tiny particles entering earth's atmosphere. They get burnt up when they enter the earth's atmosphere.
What happens when a large meteoroid enters our planet that may not be large enough to impact the planet? This creates a more fantastic sight referred to as a fireball. The fireball is also a shooting star, but it appears spectacular and fiery.
I was fortunate enough to spot one such fireball in the year 2012 a while after sunset. It so happened when I looked up, the fireball came in my line of sight. It might have lasted just a second yet it had created a lasting impression on my mind.
4. Stars and Constellations
The visible stars in night sky belong to milky way galaxy. All these stars sit in the same spiral arm where our solar system is located. We can identify some distinct patterns formed by stars known as constellations. The constellations help us in navigating the night sky.
List of Prominent Stars
1. Sirius, the brightest star in the night sky.
2. Betelgeuse, a bright red star in Orion constellation
3. Polaris or the North star that is almost stationary in the sky
4. Pleiades or Seven sisters, the brightest star cluster visible to naked eye.
List of Prominent Constellations
2. Ursa Major (containing the famous asterism - Big Dipper)
3. Canis Major
A nova represents a violent explosion of a dying star. I was able to spot a Nova that happened in Sagittarius constellation using my modest telescope. The Nova appeared like a new star in a place where there was none before. It helped me cross one more milestone in observational astronomy. Have you heard of Betelgeuse that could go supernova in sometime? If this star explodes, it could rival Moon in brightness for a few days.
5. Deep Sky Objects
The 3 Major Types of Deep Sky Objects
2. Star clusters
Nebulae and Star Clusters
Orion Nebula is visible to naked eye and through a good telescope, it reveals many details. Pleiades or seven sisters is the star cluster visible to naked eye. There are also many star clusters around Sagittarius constellation that can be spotted using a basic telescope.
Andromeda is the brightest galaxy at a distance of 2.5 million light years. The apparent size of this galaxy is six times the radius of full Moon! Still most of us would not have seen this galaxy because it gets washed away by the light pollution. A pair of binoculars will help you see Andromeda Galaxy even from moderately light polluted skies.
Milky way cannot be seen from the light-polluted city skies. I was lucky enough to spot this once from a remote area in Nagaland, India. It was visible to unaided eye since the surroundings were pitch dark and the milky way arm occupied half the sky. It was one of my best moments in night sky watching.
- James Mullaney. (2006, August 8). 111 Deep Sky Wonders for Light-Polluted Skies [Blog post]. Retrieved from https://www.skyandtelescope.com/observing/111-deep-sky-wonders-for-light-polluted-skies/
- John Pickrell. (2006, September 4). Top 10: Comets [Blog post]. Retrieved from https://www.newscientist.com/article/dn9975-top-10-comets/
- Jamie Carter. (2018, July 17). A beginner’s guide to meteor showers [Blog post]. Retrieved from https://www.skyatnightmagazine.com/advice/a-beginners-guide-to-meteor-showers/
- Nancy Atkinson. (2015, November 25). Order Of the Planets From The Sun [Blog post]. Retrieved from https://www.universetoday.com/72305/order-of-the-planets-from-the-sun/
- Glenn Chaple. (2008, March 10). Learn the constellations [Blog post]. Retrieved from http://www.astronomy.com/observing/astro-for-kids/2008/03/learn-the-constellations