August 19, 2017

Review: AstroMags.

 

Two of the leading competitors for your astro-dollar!. (Photo by Author).

Two of the leading competitors for your astro-dollar!. (Photo by Author).

 

  If you’ re like us, the modern electronic era has seen our magazine subscriptions dwindle over the last decade. Gone are the piles of magazines threatening to take over our attic or garage, as we consume more and more of our information digitally. No field changes quicker than astronomy, and up to the minute info is what we all seek on the new comet or solar flare activity that may or may not be eminent. But is there still room for astronomy magazines in our ever-dwindling astro-budget? [Read more...]

Review: The Telescope by Geoff Anderson.

Few inventions are as near and dear to our hearts as that of the telescope. Before its invention, astronomy was scarcely better than its pseudo-science companion of astrology in its knowledge of predicting the universe as it truly is. In this week’s review, we’ll look at The Telescope by Geoff Anderson out from Princeton Press as it traces the history of this noble instrument, its origins, the theory of optics, and our present day understandings and the exciting realm of telescopes yet to come.

Out from Princeton University Press!

Out from Princeton University Press!

Think you know everything about telescopes? The Telescope will take you through designs from classical refractors to Coudè focus complexities. This would serve as a good 101 for anyone thinking of building or even purchasing a telescope, as a lot of the optical basics are discussed. You can even skip through chapters, and the author even suggests that you don’t have to struggle through chapters on interferometry (but of course we did!) unless you really want to.

Stately Flandrau Observatories' 14"... (Photo by Author).

The stately Flandrau Observatory 14-inch. (Photo by Author).

The study of how early astronomers actually functioned always personally fascinates me. We all know the discoveries of Galileo, but just how did he make those refractors in a renaissance era work shop? The absurdity of some of the focal lengths used was astounding; this was required to overcome the fringes on chromatic aberration until 2-element crown and flint objectives were perfected. And don’t forget, they had to handcraft eye-pieces, as well. Just how many modern day telescope makers do that?

The 7 1/2" Merz Refractor of Quito Observatory. (Photo by Author).

The 7 1/2″ Merz Refractor of Quito Observatory. (Photo by Author).

The evolution of site selection and observatory construction is also discussed; it’s a generally underappreciated fact that seeing and turbulence makes up about 90% of your ultimate astronomical success. Early telescope users were content to perch their tubes on the ledge of a study window. It’s only been in the last century or so that site selection prior to observatory construction has really matured. In the modern era, the effects of encroaching light pollution also has to be accounted for. Telescopes have gone from backyard curiosities to behemoths of national significance.

One mother of a scope; OWL. (Credit: ESO).

One Mother of a scope… OWL. (Credit: ESO).

The modern era of scopes is also traced, from the Hale and Keck telescopes to the Hubble Space Telescope, which is appropriately given its own chapter. The chapter “When Good Telescopes go Bad” is particularly illuminating, as it demonstrates the engineering challenges that seem to plague every great instrument. It’s been said that it’s never truly a great scientific or engineering breakthrough until someone has had a nervous breakdown, and building cutting edge telescopes is certainly a case in point.  The author also addresses the innovative methods the have been developed to squeeze as much information as possible out of every photon of light. Just think, we can know speed, direction, composition and more just from “tasting” starlight. This was first developed by the breakthrough of spectroscopy, and further refinements such as interferometry and adaptive optics have pushed the envelope even further. adaptive optics itself used to be classified, as it was used primarily to peek at Russian payloads in low-Earth orbit. Some of this technology is truly amazing; for example, did you know it’s possible to “record” a conversation in a room just by measuring via laser the vibrations imparted on the windows? To this effect, the Oval Office actually employs “shakers” on its outer panes, probably not much different than the vibrate mode on your cell phone.

An "backyard" scope that would have been the envy of many of the astronomers of yore... (Photo by Author).

A “backyard” scope that many earlier astronomers would have been envious of… (Photo by Author).

A look at the key discoveries of the telescope and some of the more bizarre and unusual telescopes is also given treatment; two of our favorite are the use of liquid metal (mercury in a precisely rotated dish!) telescopes, and of course, the Laser Interferometry Gravitational wave Observatory, a “telescope” used to hunt for gravity waves.

And that’s just the beginning. The future of telescopes will see the James Webb Space Telescope, mega observatories such as the Thirty Meter Telescope (TMT) and the 100-meter OverWhelmingly large telescope (OWL) and perhaps even more exotic arrays such as the Terrestrial Planet Finder or a large crater-based instrument on the Lunar far-side.

Do give the Telescope a look if you are thinking of buying, building, or just have a passion for these grand old instruments. Telescopes represent the cutting edge of human technology, and never fail to inspire. And as astronomers, observatories are the closest thing to a cathedral to the stars that we possess!

A modern day wonder! (Photo by Author).

A modern day marvel! (Photo by Author).