How to measure a light year

Measuring the speed of light allows for a full appreciation for the size of the universe as well as the celestial objects within this phenomenal space. When thinking of a light year its important to remember that it refers to a measurement of distance rather than time.

Measuring a Light Year - read more! 

Types of nebulae

Learning the types of nebulae enhances any astronomer’s view of the universe as it’s currently known. These vast clouds, often measuring two hundred light years across, feature a differing characteristic that help define the various types.

Read more about the different types of Nebulae 

Dark matter and its implications

The Swiss astronomer Fritz Zwicky first invented the phase “dark matter” in 1934 after an exploration of the missing mass within the universe. In essence dark matter remains invisible, impossible to even touch or see.

Read more here... 

Speed of light and the size of the universe

The Speed of Light

The speed of light is used as a measurement in space. It is 186,000 miles-per-second (300,000 kilometres per second). If we look at Sirius the dog-star, it is the only star that appears to flicker different colours its distance is 8.6 light years from the earth.

The size of the Universe

The size of our Milky Way Galaxy is approximately 100,000 light years in diameter and contains 200-400 billion stars. It is estimated that there are up-to nearly 500 billion galaxies within the universe each containing hundreds of billions of stars. So you can see the math gets huge when talking about Astronomy.

Finally clear skies! a quick Astronomy scout

Well about time the skies cleared here in Darkest Essex.

Finally manged to get out and do a little star-gazing near my local dark-site. I managed to catch Canis Major and Canis Minor, the Andromeda Galaxy, the Orion Nebulae and the Open Cluster in Cancer.

All-in-all not bad trip and the new LED torch I bought for £1.99 worked a treat! So easy to read star maps with this little gadget. Of course it has been reddened-out to keep my eyes dark-adapted.


Local weather points to this weekend having clear skies too. Next time I go out I will have more specific missions for the objects I want to record.

Mastering Astronomy - Darkness and Cloud Cover with Stellarium use

As an Astronomer one of the things you will discover is that cloud cover can often cause problems. However here is my strategy for dealing with this irksome issue which afterall is really beyond our control.

Now to cut-to-the-chase I would leave my gear in its original set-up position and refer to my laptop. I use a great piece of software called Stellarium 0.10.5 which is like a virtual Planetarium, it is also FREE!

Polaris - How to find the North quick and easy (Northern Hemisphere)

To follow..