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Posts Made By: Hugh Bartlett

March 19, 2012 05:15 PM Forum: Global Warming - REAL or NOT

Clouds misrepresented in most climate models

Posted By Hugh Bartlett

It is important to recognize that clouds and atmospheric water vapor are two distinct actors affecting global climate. Here is the latest on how poorly some climate models account for the masking effect of clouds.

http://www.physorg.com/news/2012-03-climate-effects-clouds-earth.html

March 19, 2012 09:36 PM Forum: A Day in the Life of the Administrator

Trying to submit a review but it keeps bouncing ba

Posted By Hugh Bartlett

Four times today, I tried to submit a review on the new Hubble Optics 16" Ultra Light Dobsonian Structure. I've tried with and without compressed photos, but it bounces back every time. Even a simple inquiry bounced back. Is there something wrong with your server today? Please advise via personal message.

March 26, 2012 05:06 PM Forum: Global Warming - REAL or NOT

Good News: Lower Climate Sensitivity to CO2

Posted By Hugh Bartlett

Here's a recent article, albeit by someone AGW'ers will call a denier, that cites several peer-reviewed scientific articles examining and debunking the IPCC estimates of AGW:

http://www.masterresource.org/2012/03/lower-climate-sensitivity-estimates/

November 14, 2012 05:00 AM Forum: Equipment Talk

Is going from 16" Dob to 17.5" worth it?

Posted By Hugh Bartlett

I thought I had solved aperture fever by getting the biggest mirror I could get and still keep my feet on the ground, but here I go again.

My choice is between sticking with a 16" above-average 1.625"-thick f/4.5 mirror with so-so coatings, to using the same structure for a new 17.5" f/4 1"-thick mirror with excellent figure and coatings. Considerations are improved cool-down time, lighter weight, better resolution, and 20% light gain on size alone, probably more like 30% factoring in the quality of the mirror. There's a fair amount of tinkering with the hardware to make it work, but I live for that kind of challenge.

My general rule is that one has to move up 2 aperture classes to get a "Wow! That was worth it!" difference. That would put me into a 20" as my next scope. Any opinions?

December 2, 2012 12:25 AM Forum: A Day in the Life of the Administrator

Why is Ad Location blank on email notifications?

Posted By Hugh Bartlett

It would be really helpful if the seller's location could be sent with the email notification supporters are entitled to. There is always a heading in the email for it, and it is always blank.

December 6, 2012 05:30 AM Forum: Global Warming - REAL or NOT

Bill Nye takes on Marc Morano

Posted By Hugh Bartlett

This was too much fun not to pass on:

http://www.youtube.com/watch?feature=player_embedded&v=gWT-EWKIR3M

December 16, 2017 07:06 PM Forum: Global Warming - REAL or NOT

Sun is firing blanks

Posted By Hugh Bartlett

I'm not disputing the fact that human activity has a warming effect on climate, but just think we need to acknowledge the Sun's influence as well. Here is some perspective from NASA:

As the sunspot cycle plunges toward its 11-year minimum, NASA satellites are tracking a decline in total solar irradiance (TSI). Across the entire electromagnetic spectrum, the sun's output has dropped nearly 0.1% compared to the Solar Maximum of 2012-2014....A change of 0.1% may not sound like much, but the sun deposits a lot of energy on the Earth, approximately 1,361 watts per square meter. Summed over the globe, a 0.1% variation in this quantity exceeds all of our planet's other energy sources....


January 23, 2003 02:27 AM Forum: Equipment Talk

Slides

Posted By Hugh Bartlett

The Astronomical Society of the Pacific (ASP) has a 25 slide solar system set for $35 (AS 420). Their website is www.astrosociety.org

December 5, 2004 05:23 AM Forum: Equipment Talk

Where can I purchase a quality Red Laser

Posted By Hugh Bartlett

I use a Radio Shack Executive Laser Pointer (Red) to extinguish the street light in front of my house. It's a little more money ($32), but is brighter and has a greater range than the smaller $19 model.

My situation is unique, and might not fit yours. Our street is on a hill, so I can position the laser only about 5 feet lower than the photo sensor on the street light, which is important in my case because the Cobra head light fixture tilts a little back toward the pole, somewhat hiding the north-facing light sensor from view at ground level. Our street is also fairly narrow, so the distance from the laser to the light sensor is only about 50 feet.

My set-up includes attaching the laser pointer to an old finder scope, and mounting that on a photo tripod. You need some way of keeping the momentary contact switch on the pointer in the "on" position. A clothes pin could do the trick, but I made a sliding collar out of an electrical connector for running Romex into an electrical box.

The good news is that it works well for when I am doing some "sidewalk astronomy" in front of our house.

Hugh Bartlett
Oakland, CA

December 6, 2004 08:38 PM Forum: Equipment Talk

Telescope for a 12 year old?

Posted By Hugh Bartlett

I like your approach: a pair of wide angle binoculars and H.A. Rey's book "The Stars: A New Way to See Them" would be my recommendation.

However, if the little guy has his heart set on a telescope, I'd suggest either the 4.5" Orion StarBlast or an Orion SkyQuest XT4.5 Dob. Neither would break the bank, and be light years ahead of a comparably-priced department store refractor his parents probably have in mind.

Hugh Bartlett
Oakland, CA