Rich-field (or wide-field) reflectors are a type of Newtonian reflector with short focal ratios and low magnification. The focal ratio, or f/number, is the focal length divided by the aperture, and relates to the brightness of the image. They offer wider fields of view than longer focal...
Rich-field (or wide-field) reflectors are a type of Newtonian reflector with short focal ratios and low magnification. The focal ratio, or f/number, is the focal length divided by the aperture, and relates to the brightness of the image. They offer wider fields of view than longer focal...
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The canal you see today is an upgraded version of the original, as the waterway underwent a multibillion-dollar expansion finished in 2016 to accommodate NeoPanamax vessels, the supersized container ships and bulk carriers unheard of in the early 1900s but now increasingly common on the high se...
A rendering of the Wonder of the Seas, which is the world's largest cruise ship. Royal Caribbean “We’re excited to introduce guests across the world to Wonder of the Seas and its world-class features after a six-year-long process,” Mark Tamis, senior vice president of hotel opera...
Find out how PADI is spearheading a plan to reduce diving's environmental impact while fostering its reputation as a regenerative activity.
Despite these differences both fisheries fulfil requirements of Blue Growth as they are highly profitable and also considered to be ecologically sustainable. This is a very rare combination in fisheries, considering that many fish stocks worldwide are in decline. In what follows these two cases will...
used to leaving houses. as the son of a british diplomatic service officer, he spent his entire childhood globetrotting, but it was his time as a kid in japan in the 1980s—an era when the country was the worldwide epicenter for electronic innovation—that set him on a path toward tech...
When you get tired of homework several minutes’ walk in a nearby green park helps you relax at once. Or you may stand facing the lake or the seas. They will calm (not to be excited or nervous) you just like the green plants. Wonder why? Color is a key part of the answers. ...
Global warming should be taken more serious as it can result in a number of disastrous consequences.To give a clear example, the melting polar ice caps have not only caused a loss of habitat for polar bears but are also threatening seas levels worldwide. ...