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Astronomy viewing Hints and FAQ
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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