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Posts Made By: Fred Lusk

October 16, 2018 05:00 AM Forum: Solar System Observing

Observing Pluto

Posted By Fred Lusk

Update on M31-G1:

This weekend my wife and I camped two nights at Convict Lake, which is on the east side of the Sierra Nevada about 6 miles south of the town of Mammoth Lakes.  The elevation is about 7600'.  I brought my 11" for personal observing and to entertain the rest of our group, which consisted of about a dozen co-workers from several of our California offices, none of whom I had met before and only one I had talked to before.  The campground is dark…if you ignore the two nearby restrooms with interior lights shining through gable windows, nearby campfires, and vehicles driving around.

On Saturday night around 9:45 p.m., with transparency excellent, seeing ranging from good (modest wind) to great (calm), and the temperature in the mid 30s, I spotted G1 with direct vision using three eyepieces:  41 mm Panoptic, 13 mm Ethos, and 8 mm Delos.  I thought the 13 Ethos gave me the best view.  I duplicated this observation an hour later with the temperature down to 32°F.  The second view was a little better because Andromeda had climbed another 15°.  A few minutes before the second observation, and with the Milky Way still high in the sky, I recorded an average SQM reading of 21.39 mag/sq-arcsec.

Fred

October 16, 2018 05:33 PM Forum: Solar System Observing

Observing Pluto

Posted By Fred Lusk

Triton is a good one.  I've seen it several times in the 11", but never in the 8" even though it is within range.  I also spotted three of Uranus's moons (Titania, Oberon, and Ariel) the same night as one of my Triton observations, but they weren't easy.  In a friend's 20" Obsession that night, I easily saw four of Uranus' moons (adding Umbriel).

Another fun one is Hadley Rille, where Apollo 15 landed.  I've seen it in the 8" and the 11".  The moon phase needs to be just right so that one wall is still in shadow, while the other wall is getting direct sunlight.  The scene is then gray-white-black-gray.  IIRC, it's best seen about one or two days past first quarter.

November 10, 2018 07:30 PM Forum: Politics

An Inconvenient Truth For The NRA

Posted By Fred Lusk

To follow up on Richard's statement about the gun violence crisis not actually being a crisis, I wrote the following last year to debunk a similar claim made by one of my cousins.  She tries to present herself as a "mainstream liberal," but she's actually a Bernie clone.  Her ridiculous response to my essay was, "Well, those are YOUR statistics."  I guess she didn't see that I sourced every one of them.  She has a masters degree, but logic is not and never was her strong suit…just like the rest of the Left.

So, here goes:

In 2016, private citizens in the United States legally owned an estimated 326 million firearms ("legal guns" ).  This number is based on the estimated ownership rate of 101 legal guns per 100 population listed in https://en.wikipedia.org/wiki/Estimated_number_of_guns_per_capita_by_country times the total estimated population of 323,000,000.

In 2016, approximately 11,000 people were murdered with a gun.  See https://ucr.fbi.gov/crime-in-the-u.s/2016/crime-in-the-u.s.-2016/tables/expanded-homicide-data-table-4.xls.

Of those murders in 2016, an estimated 20% were committed with legal guns and the remaining 80% or so (including most of the multiple murders) were committed with illegally obtained firearms (“illegal guns”).  See https://www.washingtonpost.com/news/wonk/wp/2016/07/27/new-evidence-confirms-what-gun-rights-advocates-have-been-saying-for-a-long-time-about-crime/?utm_term=.ea61a03f8477.

So, 20% of 11,000 is 2,200.  If we conservatively assume one murder per legal gun, then the upper bound for murders committed by legal guns as a percentage of total legal guns is 0.000675%.  I do not wish to minimize the tragedy of each of these murders, but 0.000675% is statistically insignificant.  We have a huge population and 2,200 is a very small number in comparison.

Here is another way to look at this:  99.999325% of legal guns were NOT used to murder someone.

It should by now be painfully obvious, even to those on the Left, that legal guns, and in fact guns in general, are NOT the problem.  If guns were the problem, we would have a statistically significant number of murders committed by those 326 million legal firearms, perhaps several million per year or maybe tens of millions.

The problem is, primarily, thugs and crazies with illegal guns and no amount of additional gun control legislation is going to fix that. This is a human problem, not a gun problem.

If y'all on the Left refuse to believe the facts, then you are willfully in the wrong.

========================

It is also useful to compare gun murders against the darling of the Left, namely abortions.  In 2016, approximately 880,000 babies were "legally" murdered via abortion (see http://www.johnstonsarchive.net/.../ab-unitedstates.html).

That is 80 times the total number of murders with all guns and 400 times the number of murders with legal guns.  How can y'all on the Left not see this?

Since the 1973 Roe v. Wade decision, approximately 60 million babies in the United States have been murdered via abortion (see http://www.numberofabortions.com/).

And, this toll has fallen most heavily, by percentage, on the black community.  However, this stands to reason, since Margaret Sanger, the founder of Planned Parenthood—America’s largest abortion provider by a large margin—was a racist who specifically targeted blacks (see, among many others sites, https://www.americamagazine.org/.../margaret-sanger-was...).

If the Left really cared about human life, they would focus first on the far bigger problem of abortion.  But, the Left is all about control of the citizenry and does not care at all about human life.

December 1, 2018 07:35 AM Forum: Comets

Comet 46P/Wirtanen

Posted By Fred Lusk

Even under the Bortle Class 6 to 7 skies of Fresno, CA, I was able (barely) to spot Comet 46P at about 10:00 p.m. tonight with handheld 15x70 binoculars.  Fortunately, it rained over the past couple days and the seeing and transparency were both much better than average.

The comet was right where it was supposed to be, which I confirmed with the star field shown in a detailed finder chart from SkyTools 3.  The comet is bright (~m3.4), but so large (~1.5°) that its surface brightness is low and that's a killer under my suburban skies.  The core was slightly brighter than the rest of the comet, which made it easier to spot.

Next Saturday, if conditions permit, I will be observing with my 11" SCT at 6,500 ft in Kings Canyon National Park and Comet 46P is in my observing plan.

January 21, 2019 02:41 PM Forum: Film Astrophotography - Imaging and Processing

Today's 35mm film off the shelf

Posted By Fred Lusk

Brian…

I still shoot 35 mm sometimes.  For years I used Kodak EliteChrome 200 and 400 and Fuji Provia 400, mostly for star trails and wide-field piggybacked images.  The two EliteChromes have been off the market for a while, so what little I still do is with Provia 400.  All three slide films pick(ed) up red nebulas very nicely (unlike the color print films I tried) and have/had excellent reciprocity characteristics.

Here is a 10°x15° swath of the summer Milky Way that I shot in about 2004.  IIRC:  Olympus OM-1N pickybacked on a Celestron C5+/Orion SkyView Pro combo, 135-mm f/3.5 Zuiko lens @ f/5.6, EliteChrome 200, 23 minutes.  The Fuji would have produced similar results, but required a shorter exposure.

Fred

January 21, 2019 02:44 PM Forum: Film Astrophotography - Imaging and Processing

Today's 35mm film off the shelf

Posted By Fred Lusk

....and here is a 4h40m star trail.  My notes are hard to get to at the moment, so IIRC:  Olympus OM-4T on tripod with locking cable shutter release, 24-mm f/2.8 Zuiko lens @ f/8.0, Fuji Provia 400.

BTW, I took both shots at our club's high-elevation observing site:  Courtright Reservoir in eastern Fresno County, elevation 8200 ft ±.

Fred

January 22, 2019 01:43 PM Forum: Film Astrophotography - Imaging and Processing

Today's 35mm film off the shelf

Posted By Fred Lusk

Brian…

Slides work for me because I have a Nikon CoolScan V slide scanner.  It does a nice job on astrophotos, in fact better than the local service I used to use before I got the scanner (c.2005).  I am slowly working my way through scanning >8,000 slides I took over the years (mostly non-astro), but finding time can be difficult.  One slide takes about 1.5 minutes and I like to do a roll at a time (either 24 or 36 slides).

Regarding my comment above about reciprocity failure....
If you're not familiar with the term, here is an explanation:  https://filmphotographyproject.com/content/howto/2011/10/what-reciprocity-failure/

In short, back in the day, the linear exposure model for photography would break down at exposures as short as a few seconds up to several tens of seconds.  For daylight exposures, this wasn't a problem.  But it was/is a big problem for astrophotography.

My first few tries with color print film showed me that reciprocity failure (and the inability to pick up red nebulas) would be a problem.  However, the three slide films I mentioned above solved the problem.  It turns out that as film was dying, some of the best films ever were being produced.  Back in the early 2000's I did an experiment with the EliteChrome 200 at our Courtright site.  I pointed my piggybacked camera at Cygnus and took a series of exposures:  1 s, 1 min, 2 min, 4 min, 8 min, and 16 min.  The 1 s exposure got the Northern Cross and little else..  The 1 min exposure picked up the brightest part of the Milky Way and the North America Nebula.  The best part was that the succeeding doubling of exposures produced a doubling of the light gathered on the film (at least it looked that way to my untrained eye).  My guess is that the EliteChrome 200 would keep gathering light up to maybe 20-30 minutes.  My results with the EliteChrome 400 and the Provia 400 leads me to believe that they have similar excellent reciprocity characteristics.

Fred

March 16, 2019 11:27 PM Forum: Equipment Talk

Portable scope for BOTH Terrestrial and Celestial viewing and simple photography

Posted By Fred Lusk

A used Celestron C5+ or the current C5 spotter would be good choices.  I have the former, my son has the latter.  We both use ours for terrestrial and celestial viewing, although I don't use mine as much as I used to for celestial viewing because I have two larger scopes.  For portability, the C5+ on the table-top wedge is a great choice.  For celestial viewing and astrophotography, I also have the Celestron Advanced VX mount.

March 25, 2019 04:11 AM Forum: Politics

No surprises here

Posted By Fred Lusk

Richard…

I need to correct your spelling.  It's "Newsweak".  smile

Fred

August 5, 2019 05:44 AM Forum: Solar System Observing

Did I see the Grace-FO satellites this weekend?

Posted By Fred Lusk

I'm usually not very interested in tracking satellites, but I spotted something unusual (to me) this weekend and would like some help figuring out what I saw.

First, some background:

I am a long-time member of Central Valley Astronomers in Fresno, California.  I spent Friday and Saturday night at my club's high elevation observing site near Courtright Reservoir in the Sierra Nevada mountains east of Fresno (37°04'54" N, 118°57'47" W, elevation 8140 ft ±....and primitive camping).

At about 00:50 on August 3 (i.e. very early yesterday morning), I was attempting to find asteroid (15) Eunomia.  My SkyTools 3 observing plan gave a location of RA 21h32m15.8s / DE -05°40'33" (JDATE at the transit time of 01:42).  The SkyTools 3 finder chart I printed gave a location of RA 21h30m03.5s / DE -05°55'48" (J2000 at 01:00).

I was using a Celestron CPC-1100 HD and a 41mm Panoptic eyepiece, which gives a calculated FOV of 59.7 arcminutes.  I entered the JDATE coordinates into the hand controller (appropriate since the mount was aligned on stars that themselves are at JDATE coordinates) and found the exact star field shown in the J2000 finder chart.  I always find this match to be encouraging. smile

I marked on the finder chart about two dozen of the brighter stars (and a few fainter ones) that I saw in the eyepiece, including Beta Aqr.  However, I didn't spot the asteroid, which at magnitude 8.4 would have been brighter than about half of the stars I marked.  Unfortunately, sometimes a SkyTools 3 finder chart for an asteroid completely misses the mark, even with updated orbital elements.  It's happened to me maybe 6 times out of 100.  Also, most of the time, the asteroid that is plotted in the center of the FOV is based on "extrapolated orbital elements" and a second version of the asteroid is plotted nearby that is based on a recent epoch for the orbital elements (in this case 2017.13).  I have found that the "off center" version of the asteroid is almost always where I actually see the asteroid when I look, so my current practice is to recenter the finder chart to the latter version of the asteroid.

Now, what I saw:

As I was marking stars on the finder chart (some as faint as 13th magnitude) I spotted a faint, equal brightness "double star" that wasn't on the finder chart.  I roughly estimated both "stars" to be about 11th magnitude and the separation to be maybe 45 arcseconds.  Then I noticed that the "double stars" were moving....in a south-to-north direction....very nearly through the center of the FOV....at about the speed that I have seen other polar satellites move.  Intriguing.

When I got home this afternoon, I did a Google search for "twin polar satellites" and the only thing that came up were the Grace and Grace Follow-on missions.  The Grace satellites are no longer in orbit, while the Grace-FO satellites were launched in May 2018 and are still active.

Except for ISS, I have limited experience tracking satellites.  The satellite tracking app on my iPhone has at least 100 satellites, but Grace-FO isn't included.  There is probably something on the Internet that would allow me to translate the ground track into the sky for my location, time, and FOV, but I don't know where to start.  I did a few Google searches using relevant terms, but didn't find anything that would allow me to verify which satellite pair went through my FOV.

So, Astromart experts, any ideas?  Thanks in advance.