Monolith149 Daily

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Buying a Telescope - Part 3

Day 27

Some parting thoughts.

Magnification

There’s a common misconception that telescopes are all about magnification. One sure sign of a questionable telescope is one that puts its magnification up front. Worse is one that advertises 200x, 300x, and more.

Buying a Telescope - Part 2c

Day 26

Recommendations continued.

The 2.4-inch Refractor

I always recommend binoculars as a good way to start observing. However, if you’re a kid who wants a telescope, binoculars might be a disappointment. Many astronomers would scoff at the old 2.4-inch standard but I think this is a fine telescope to start with. It’s the lowest cost beginner scope and you can use it to see the beginner objects.

Farewell Tom Magliozzi 1937-2014

Day 25

I don’t know when or how I first happened to hear the show Car Talk but I quickly became a huge fan. When I couldn’t listen to the show live, I got a subscription through Audible and would download MP3s of the show and burn them onto CDs to listen to.

Click and Clack were hilarious, their personalities were infectious, and their ability to diagnose car problems preceeded and exceeded Dr. House’s corresponding ability at playing the medical Sherlock Holmes.

Probably like most listeners, it was a while before I learned that they were actually both MIT graduates, Tom had a Ph.D., and that they both played Bluegrass music.

I haven’t been a listener for a few years but I’ve always remained a fan.

This is one of my favorite videos. Martin Guitar presents Click and Clack with a special Car Talk edition guitar. Then they perform.

Martin Guitar Presentation

Articles

From the Car Talk Blog
Wall Street Journal
NPR
Boston.com

Buying a Telescope - Part 2b

Day 24

Recommendations continued.

Binoculars

The first recommendation is always binoculars. They are two telescopes instead of one. They are the most portable telescopes you can get and you get two, one for each eye.

The investment is around $100. It’s a good investment because, regardless of how serious you become as an astronomer, you always have a need for binoculars. There are some objects that don’t look as good in a telescope. A total lunar eclipse is an example. When I was a serious deep sky observer, I often found objects or at least the stars surrounding their location using binoculars.

Buying a Telescope - Part 2a

Day 23*

Recommendations.

Orion

Since the planetarium days, I’ve favored Orion Telescopes as an excellent and reliable source of reasonably priced and good quality telescopes. Their telescopes are well-made, of outstanding quality, and not the absurdly overpriced telescopes you find at your nearest big store.

What we used to call those “department store” telescopes, which typically were of poor quality and vastly overpriced. The classic starter telescope is a 2.4-inch (60-mm) refractor on an altazimuth mount. I’ve seen the “department store” versions of these for $250, even $400. The are often advertised as 400X or 300X magnification (which is absurd and meaningless). That same telescope, of higher quality, outstanding and appropriate accessories at Orion is $100.

I’m not going to cover all of the different types of telescopes but just refer you to the web for that. You should read about refractors and reflectors. Equatorial mounts and altazimuth. Dobsonian, Newtonian and Schmidt-Cassegrain, Maksutov and catadioptric telescopes in general. It sounds like a lot, but the basic ideas are not complicated.

*Posting Day

I wrote this post while away from home on Sat 2014-11-01 and didn’t actually post it on day 23 but after midnight at 1:14 on day 24. I don’t actually have a way to post entries when away from home so I can only write them and then post them later. So, in fact, I didn’t actually do any of the work on this post on day 23.

Orion telescope.com

Buying a Telescope - Part 1

Day 22

Back in the planetarium days I was frequently asked about buying a telescope, especially around Christmas. Over the decades since then people still ask me from time to time and still ask more often around Christmas. I had a pretty well-formulated answer eventually and I’ve written it up a number of times. (I’m not sure if I know where any of those old write ups are).

We’ll start with the basics, what’s important when it comes to telescopes: aperture, mounting and portability.

SQRL!

Day 21

For several months now Steve Gibson of GRC.com and Security Now has been working on a new authentication protocol he named SQRL, the Secure Quick Reliable Login. On his web site he describes what happens when you log into a site, say Amazon, using SQRL (assuming Amazon adopted it).

The website displays a QR code, described as a “SQRL code,” beside the usual userid and password login prompt.

  • The user can tap or click directly on the SQRL code to login, or launch their smartphone’s SQRL app, and scan the QR code.
  • For verification, SQRL displays the domain name contained in the SQRL code.
  • After verifying the domain, the user permits the SQRL app to authenticate their identity.
  • Leaving the login information blank, the user clicks the “Log in” button… and is logged in.

The approach is highly secure, difficult to attack, easy to implement, and easy to use. He describes details at his site.

This is an elegant solution to the problems that come from dealing with passwords and I hope it continues to climb since it’s taken off!

SQRL at GRC.com
Security Now
Episode 424 on SQRL
Sqrl.pl Illustrated Guide

Are Quasars Dying?

Day 20.1

From The Daily Galaxy.

“We have been able to confirm that, indeed, apart from the highly energetic and rapidly evolving quasars, there is another population that evolves slowly. This population of quasars appears to follow the quasar main sequence discovered by Sulentic and colleagues in 2000. There does not even seem to be a strong relation between this type of quasars, which we see in our environment and those ‘monsters’ that started to glow more than ten billion years ago”, says Ascensión del Olmo another IAA-CSIC researcher taking part in the study.

They have, nonetheless, found differences in this population of quiet quasars. “The local quasars present a higher proportion of heavy elements such as aluminium, iron or magnesium, than the distant relatives, which most likely reflects enrichment by the birth and death of successive generations of stars,” says Jack W. Sulentic (IAA-CSIC). “This result is an excellent example of the new perspectives on the universe which the new 10 meter-class of telescopes such as GTC are yielding,” the researcher concludes.

Rocket Explodes

Day 20

From New Scientist.

The Orbital Sciences Antares rocket…

…flying cargo to the International Space Station exploded just 14 seconds after lift-off last night, creating a spectacular fireball and shockwave as the fully fuelled rocket crashed back down onto its launch pad.

No one was hurt when the uncrewed spacecraft was destroyed, but the loss will dent attempts by the spacecraft’s builder, Orbital Sciences Corporation of Dulles, Virginia, to build confidence in its ability to supply ISS cargo services to NASA.

The 19-Inch Rack

Day 19

Last night, while driving home, I stopped at an intersection where work was being done on the traffic signals. Looking at the open control box I suddenly realized it was just a 19-inch rack inside the silver box. I think I even saw a network switch in there and a surprising number of mounted devices. That makes sense.

I’ve worked around the standard 19-in racks in data centers for a long time. Even before that, when I was in school, it was common for a physics lab to have a row of several 19-in racks. They were usually filled with instruments, controllers and maybe even an occasional computer though microcomputers, small enough to fit in a rack, were just beginning to appear on the scene.

Even large telescopes will have the standard racks mounted right on the back of the telescope, like the 120-inch telescope here at the Lick Observatory on Mount Hamilton.

Where did they begin? An on-line article “Audio-Video Equipment Racks” credits Westinghouse.

The origins of rack mounting dates to the days of industrialist George Westinghouse way back in 1890. Westinghouse had first designed 19-inch shelving to house relay gear used in his railroad industry. Eventually, early telephone companies also adopted this 19-inch width.

For that reason they are sometimes called “relay racks.” Wikipedia says the relay rack name came from telephony and then appeared in railroad signaling by 1911.

The Electronic Industries Alliance (EIA) “standardized them in its 310-D standard, first published in 1965.” That standard included the 1.75-in rack space height and the 19-in width (482.6 mm).

Wikipedia says,

The 19-inch rack format with rack-units of 1.75 inches and holes tapped for 12-24 screws with alternating spacings of 1.25 inches and 0.5 inch was an established standard by 1934. The EIA standard was revised again in 1992 to comply with the 1988 public law 100-418, setting the standard U as 44.5mm (15.9mm + 15.9mm + 12.7mm), making each “U” officially 1.752 inches.

19-inch rack at Princeton.edu/~achaney.
Audio-Video Equipment Racks – Part 1 in the Practical Home Theatre Guide.
19-in Rack on Wikipedia.

Photo credit: US National Oceanic and Atmospheric Administration.
Lick photo: by the author.