Time to dispel jargon myths with a bit of a telescope glossary. The larger a telescope’s aperture (the size of its main lens or primary mirror) the more light is collected and more fine detail is revealed. For example, a 200 mm aperture collects four times more light than a 100 mm telescope. Under ideal conditions, a 100 mm telescope reveals stars down to magnitude +11.8, while a 200 mm telescope will show stars down to magnitude +13.3.
The comet will gradually fade and become more challenging to observe as it continues its journey away from the Sun. All you need is a view of the sky and a pair of eyes, although binoculars and affordable telescopes can enhance the experience. Concise and self-contained, this textbook gives a graduate-level introduction to the physical processes that shape planetary systems, covering all stages of planet formation. Discover the best telescope for adults right here. provides a self-contained account of the modern theory of planet formation and, for more advanced readers, carefully selected references to the research literature, noting areas where research is ongoing. Astronomy in Action’s Universe is a program supporting concepts from upper level science courses such as Physics, Chemistry, Environmental Science, and Earth & Space Science. Perhaps surprisingly, you note that the stars create the same patterns from Mars as they do from Earth.
If there is only one matching location, SkySafari will use it. When you are orbiting another star, SkySafari only displays stars in the Hipparcos catalog, and nearby stars whose distances are well known. SkySafari does not display faint Tycho or Guide Star Catalog stars, because their positions in three-dimensional space are unknown. Therefore their apparent positions when seen from outside our Solar System cannot be accurately depicted. Make sure your two alignment stars are at least 10 degrees apart; 90 degrees apart is ideal.
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All of which means it has a slow f/10 focal ratio, ideal for high magnification and tighter fields of view which are what you need to see intimate details on a planet’s surface. The aperture is 6″, the same as the Dob featured above but this model is a compound telescope, a mix of lens and mirror which is specially configured to give a long focal length in a small tube. If you choose to upgrade your eyepieces from the cheap 25mm and 10mm provided (which we recommend you do) it would be easy to see this as a telescope for life. Dobsonian telescopes are really simple to setup and use, and this is no exception. You will need to collimate the mirror from time to time to keep your focus sharp, but that’s easy to do with our guide. Maksutov-Cassegrain (MKC) telescopes are perhaps ‘the daddy’ of telescopes for viewing the planets.