Astronomy viewing Hints and FAQ
Starting out and viewing the night sky
When you first start out in this hobby, it is commonplace that you look to immediately getting a telescope to start enjoying the wonders of the night sky. However many astronomers would say this is not essential at the start. Although a telescope will open up access to the planets and many deep sky objects, there is still plenty to see and do with simply your naked eye or a half decent pair of binoculars. Here are a few examples...
Naked eye viewing
There are many things you can look out for just by going outside and looking up. whether its finding the well known 'plough', the 'summer triangle' in the summer or finding the distinctive constellation of Orion and Orion's belt in the winter months. Its very rewarding recognising the patterns made by the stars night by night. Also, at least 4 of the planets are easily visible to the naked eye if you know where and when to look. In order to know what to look for you need to use either a planisphere or planetarium software. They both sound rather technical things, but both are simple to use and will soon get you looking in the right place. (more info on software below).
Even some deep sky objects can be easily seen with the naked eye like the Pleiades star cluster (better known as the seven sisters), The beehive cluster or The Andromeda galaxy. The Andromeda galaxy is the only galaxy (with the exception of our own) that can be easily seen with the naked eye. This also makes it the most distant object visible to the human eye.
Objects visible and ideal for Binoculars
-The Moon
-Andromeda Galaxy
-Pleiades cluster
-Beehive Cluster
-Constellation of Cygnus (for sheer star numbers)
-Orion Nebula
-Perseus Double Cluster
-Alcor & Mizar double star
The Milky Way
The milky way is the galaxy that we live in. For this reason its very large and stretches across the whole sky from horizon to horizon. A collection of billions of stars and dust making it look like a giant thin cloud sweeping across the heavens. The only problem is its large, faint and diffuse so in order to see this spectacular sight you need a certain set of conditions. First and foremost, you cannot view it anytime around full moon. Our closest neighour can be the worst light polluter of them all and its brightness simply washes out the milky way in the sky. Ideally, the best time for viewing are the days nearer to new moon. Also, you must be out of light pollution as best you can. The milky way can be seen from smallish towns but its beauty is somewhat diminished. Finally, but quite importantly, the milky way is not even visible at certain times of the year. During the equinoxes it hugs around the horizon, making it almost impossible to see. The best time of year is during late summer when stretches straight up above us in the sky and when the nights start to get dark again. The best month of them all is August as you do not have to wait until unearthly hours for the night to get completely dark (and it can be reasonably warm outside!)
How to learn where to look
Now that you know just how much is up there, how do you know where to look? Well there are a number of ways. Its down to personal preference. For me, I prefer software. The best software I can recommend is stellarium. Its easy to use, very realistic and best of all free to download! It can re-create the sky at any given location on Earth at any time showing the position of all the planets, most well known deep sky objects and stars. A useful too for naked eye, binocular and telescopic viewing. Another tool is a planiasphere, a handheld card showing the sky which can be adjusted to show the sky at certain times of the year. As a third option, there are a number of astronomy magazines available from WH Smith or good magazine stores. These always have star charts and guides to the months observing
Object finder guides - use these guides to find these popular sky objects
Where to find Polaris (the Pole Star)
Where to find the Albireo double star
Where to find the Double Cluster
Where to find the 'Double Double'
Where to find the Hercules Cluster (M13)
Where to find the Andromeda Galaxy (M31)
Where to find the Orion Nebula (M42)
Where to find the Whirlpool Galaxy (M51)
Where to find the Ring Nebula (M57)
Asterism's, what are they? and examples
An 'Asterism' is a star pattern that is not a constellation. It may be part of a constellation or have more than one constellation within it. Some of them are well known by the general public and some are not so well known. However, viewing an asterism will clearly reveal why it has its given name.
The Plough (aka The Big Dipper)
The little Dipper
The Summer Triangle
The Winter Triangle
The Coathanger
Frequently Asked Questions
Beginners Questions...
Q: How far away is the Sun?
A: About 93 million miles (or 150 million kilometers). Travelling at the speed of light it would take 8 minutes and 20 seconds to get there (Also meaning it takes this long for it's light to reach Earth)
Q: What is the closest star to us apart from the sun?
A: The closest star apart from the sun is Proxima Centauri It has a much brighter companion called Alpha Centauri making it a double star system. It lies approx 4 light years away (if you where travelling at the speed of light it would take 4 years to get there!)
Q: How come the closest star (excluding the sun) is not the brightest?
A: The stars take many different forms and sizes, the closest star does not shine very brightly and is also very small in size when compared to all the other known stars.
Q: What is the brightest star (apart from the sun)?
A: Sirius (aka The Dog Star). It has a visual magnitude of -1.44 making it twice as bright as the next brightest star. The only objects in the sky that are brighter are The Sun, Moon, Venus, Mars and Jupiter.
Q: What is the closest planet to Earth?
A: This can depend on what time/date it is. The planet that gets the closest at any one time is Venus. It's orbit around the Sun is within ours. However at other times Mars can be closest if Venus is the opposite side of the sun and Mars' orbit comes next to the Earth's.
Q: What is the brightest planet?
A: Venus, it has a maximum visual magnitude of around -4.4 and is easily the third brightest object in the night sky (the other two objects being the sun and moon). Venus can only be seen just after sunrise or just before sunset as it always stays relatively near the sun. Venus always looks brilliantly bright and is often mistaken for planes with landing lights on or UFO sightings. In the right conditions it can cast faint shadows. It is rarely seen in a completely black sky.
Q: Where and what is the milky way?
A: 'The Milky Way' is actually the galaxy that we are inside. It's a strange name quite different from the others like 'Andromeda' etc. The milky way can be seen as large faint 'milky' cloud stretching across the whole sky from one horizon to the other (hence it's name). Filled with countless stars, clusters and nebulae in the right viewing conditions it can be an inspiring sight. It can be hard to spot in light polluted urban area's and many people living in cities and towns hardly ever see the very galaxy we live in! The best time to view it is during the summer months when it stretches right overhead.
Intermediate Questions...
Q: The moon orbits the Earth every 27.3 days, how come we can only ever see one side of it?
A: The moon actually does rotate as well as orbit the Earth but it happens to take exactly the same amount of time to rotate once as it does to orbit the Earth once. So one side of the moon is fixed in a position to always faces us.
Q: How come there are lots of great pictures of Nebulea and Galaxies showing lots of colour but through a telescope I see no colour?
A: Camera's taking long exposures are much better at capturing colour at low light levels than the human eye. Our eyes cannot pick up colour from such low light levels so the object looks simply gray. A very good example being the Orion Nebula.
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