Product reviews: 32mm SP-Series Super Plossl eye-piece
By: Matt Kelly
Plosslscan be considered as the work horses of the eyepiece world, very prevalent, hard working and versatile. Plossl refers to the way in which the eyepiece is designed, traditionally only 4 or 5 lenses are used which minimises any aberrations or scattered light that a...
Product reviews: Dual Speed Crayford Focuser for Skywatcher refractors
By: Matt Kelly
A good focuser is of the utmost importance to the visual observer as well as the astrophotographer. After all, what use are the best optics in the world if you can't bring them to pin sharp focus easily and effectively. This dual speed Crayford from...
Product reviews: Celestron Omni 6mm eye-piece
By: Matt Kelly
The Celestron Omni 6mm is a Plossl design. Traditionally Plossl eyepieces contain 4 or 5 lenses. The Omni 6mm is typical in this regard and contains 4 lenses. The lenses are arranged in a symmetrical fashion, being 2 goups of 2 lenses closely spaced. The...
What is astronomy's explanation for the Star of Bethlehem
By: D. Vogt
Searching for a scientific explanation (i.e. an astronomical explanation) for the Star of Bethlehem would, to many skeptics, be putting the cart before the horse - it's much easier for people who do not believe the gospel narratives to say that the Star of...
Overview of how planetary stars die
By: D. Vogt
Since planetary stars (stars with planets) are essentially the same as other stars, they die the same way. All stars die when they run out of sufficient hydrogen in their cores, and the manner of their death is determined by their size. Essentially, the larger...
Product reviews: Pentax XW 14mm 1.25 inch eye-piece
By: Matt Kelly
Pentax have long been synonymous with quality and as with anything else in this world quality does have it's price. In the XW 14mm's case it's a rather hefty £250 price tag. That may seem an extortionate amount to pay for an eyepiece but...
Product reviews: Celestron X-Cel 5mm eye-piece
By: Matt Kelly
The Celestron X-Cel 5mm is a high powered eyepiece for planetary and Lunar viewing. The 5mm focal length makes for a high magnification whichever telescope it'sbeing used with. Unlike the majority of eyepieces out there Celestron have used 6 lenses (or elements as they're known)...
By: Tarek Musslimani
Stars usually maintain a state of equilibrium with zero net forces acting on them. The main force that acts on the stars is the gravitational force which tends to shrink the size of the star and forces it to collapse. The other opposing force to...
Product reviews: 12.5mm SP-Series Super Plossl eyepiece
By: Matt Kelly
Skywatcher make a wide array of eyepieces from the extravagantly expensive right down to what could be considered the budget range. Their sp plossl series falls squarely into the latter category. A low cost eyepiece that can be used on a plethora of astronomical objects...
Legends about the stars
By: Gary Wonning
Sirius, the Dog StarSirius, more commonly known as the Dog Star is located just east of Orion's Belt in the southern sky. It is known as the Dog Star because it is part of the constellation known as the hunter and Sirius represents the head...

 

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