Not all amateur astronomers have binoculars or a telescope. Some folks might be interested in watching by the naked eye, some might not have money enough to purchase a telescope, some might be looking for the right instruments for him/herself. Whatever the reason is, the fact is that not everybody owns a telescope or binoculars. What if they try to observe from a crowded city, say New York or Tokyo? They probably suffer from artificial lights, right? Could they have any changes to observe better without changing their location? Oh yes, they could use the good old black tube!

One of the oldest and most simple tools people have used to help skywatching is a black tube. The black tube is a useful tool for observing dim objects of deep space. The idea using of a black tube is that it prevents additional light entering your eyes. When the eyesight is narrowed it is much easier to search dim objects.

There are two types of tubes: one with diameter of 3-5 cm. and one with diameter of 10-15 cm. The first one is used with one eye while the other one is used with both eyes. The bigger one is better because two eyes can see dim objects better than one eye. The tube can be plastic or even wooden. The important thing is that inside it is painted black in order to minimize reflections. What should be the length of a black tube? A good length is about one meter which provides pretty much the same eyesight as 7×50 binoculars.

A black tube can also be used in hunting planets. It is a great and easy to use tool, and what’s the best, in practice it costs nothing. You can use whatever tube you find, such as water pipes of cardboard tubes. The only important thing is that it is at least close the the mentioned sizes and you paint it black inside (if not black already). Make yourself a black tube and see the night sky better than by plain naked eye!