January 2009 - Utah-Astronomy - mailman.xmission.com

Re: [Utah-astronomy] Threads that never had a chance on Utah-astronomy
by zaurak＠digis.net 26 Jan '09

26 Jan '09

Seriously, I remember a RTMC where a lot of people had Day-Star H-Alpha filters, I brought the one belonging to SLAS. An individual had a DayStar with similar set-up of the one SLAS owns, it was completely powered by solar panels that doubled as a sun shade. I was first class, we should do something similar for our DayStar Solar Scope. Charlie Green's 29" was sturdy (heavy) enough that a wind powered telescope drive could have been feasible. One of our innovative SLASers had a sand powered drive. Erik --- chuck.hards(a)gmail.com wrote: From: Chuck Hards <chuck.hards(a)gmail.com> To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] Threads that never had a chance on Utah-astronomy Date: Mon, 26 Jan 2009 11:25:24 -0700 Think "Green": Solar-powered telescope drive Wind-powered telescope drive Bio-diesel-powered telescope drive Ice scraper for refractors _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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Threads that never had a chance on Utah-astronomy
by Chuck Hards 26 Jan '09

26 Jan '09

Visual supernova hunting with 30mm binoculars A solar toaster attachment that replaces the secondary mirror on the Grim scope Forensic Astronomy Burning ants with the Bogdan refractor SLAS streetlight BB gun night Hand-guide while imaging with that alt-az mount "Spot the commie" AAVSO certificate for right wing astronomers Can you find Jesus in your telescope? What's your favorite Rap music to play loudly at star parties? How come we can't get as many volunteers for the Boy Scouts, as we do for the Girl Scouts? Official club hat: Tin foil

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New M-1 shot
by Patrick Wiggins 26 Jan '09

26 Jan '09

I finally got around to processing, assembling and posting images of M-1 I took a few nights ago. Posted is the clear, red, green and blue images and the color which I made by adding the others together. The clear is a compilation of 30 one minute exposures. Each of the color files are compilations of 15 one minute exposures. As before I'm happy to email anyone who asks for the FIT versions (the ones online are JPG) so they can try their hand at making their own color image. http://www.slas.us/gallery2/main.php?g2_itemId=68&g2_page=2 Clear skies (please), patrick

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Chuck Hard's List
by rcfry＠comcast.net 26 Jan '09

26 Jan '09

Chuck all great ideas but why not add a "BLACK-HOLE MARATHON" ? Because they are inherently dark, we could schedule this on a full moon night thus giving more contrast. For that matter, we could have this in the middle of the day to add even more contrast. Who knows, don't knock it until you try it! Rodger Fry

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Re: [Utah-astronomy] Threads that never had a chance on Utah-astronomy
by JayLEads 26 Jan '09

26 Jan '09

Star Party near the SLC Airport with green lasers to point out constellations SLC Astro Tubing Party at Solider Hollow using your Dob Tube Build a voodoo doll activity for your neighbor who never shuts off their porch light(s) On 2009-01-26 06:09, Chuck Hards wrote: > Visual supernova hunting with 30mm binoculars > > > A solar toaster attachment that replaces the secondary mirror on the Grim > scope > > > Forensic Astronomy > > > Burning ants with the Bogdan refractor > > > SLAS streetlight BB gun night > > > Hand-guide while imaging with that alt-az mount > > > "Spot the commie" AAVSO certificate for right wing astronomers > > > Can you find Jesus in your telescope? > > > What's your favorite Rap music to play loudly at star parties? > > > How come we can't get as many volunteers for the Boy Scouts, as we do for > the Girl Scouts? > > > Official club hat: Tin foil >

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Re: [Utah-astronomy] Threads that never had a chance on Utah-astronomy
by zaurak＠digis.net 26 Jan '09

26 Jan '09

Good night all, The only white dwarf I know well is my dog, she is surely the Sirius B variety. I am relieved that I got her brown emissions picked up before the latest snow. Erik --- chuck.hards(a)gmail.com wrote: From: Chuck Hards <chuck.hards(a)gmail.com> To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] Threads that never had a chance on Utah-astronomy Date: Sun, 25 Jan 2009 23:18:24 -0700 Observing while white-water rafting Olfactory Astronomy Shotgun-powered telescope drive Astronomy for sleep-walkers _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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Re: [Utah-astronomy] White dwarfs and YOU
by zaurak＠digis.net 25 Jan '09

25 Jan '09

Chuck and Kim, My experience has been that O3 filters are of little help with many planetary nebula, a consensus on wether it helped with the Helix did not occur at SPOC with many experienced SLAS observers last year. It is kind of large for the Grims' general field of view. The best views come from smaller lower magnification scopes (IE <32"). In the case of the helix, I read (from a google search) that expelled gases from the red giant can travel at different rates and have different temperatures, so they become illuminated by mixing gases of different temperatures, and form some comet like patches that could perhaps from pluto size objects. The Helix is the closest of the planetary nebulas, so I imagine more subtle illumination can be seen. It does seem the very definition of a planetary is an emission nebula with its primary illumination coming from a White Dwarf. Erik --- kimharch(a)cut.net wrote: From: "Kim" <kimharch(a)cut.net> To: "'Utah Astronomy'" <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] White dwarfs and YOU Date: Sun, 25 Jan 2009 20:51:55 -0700 Like you, Chuck, I haven't had the time to do any immediate research, but I seem to recall that the radiation energy (what radiation I can't say - I'm no physicist, either) that causes the pn to be visible is ionizing radiation causing the pn to emit light from O3 emissions - therefore, not merely a reflection phenomena, but I’m certain that could also be a component. Kim -----Original Message----- From: utah-astronomy-bounces(a)mailman.xmission.com [mailto:utah-astronomy-bounces@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Sunday, January 25, 2009 8:18 PM To: Utah Astronomy Subject: Re: [Utah-astronomy] White dwarfs and YOU No, I didn't mention that. Jerry was the one who posted about the visibility of white dwarfs in a cataclysmic variable system, not Bishop. I was attempting to distance that from Bishop and try to underline the differences. In my post, Bishop's comments were in quotes, mine were not. Sorry for the apparent confusion. Also, I need to research this, but I'm not sure that planetary nebula are illuminated by the central star, but by the expelled material colliding with material ejected previously. These are glowing, ionized nebula, not merely reflection nebula. On Sun, Jan 25, 2009 at 8:05 PM, <zaurak(a)digis.net> wrote: > You also mention that he is talking about white dwarfs from cataclysmic > double stars. Perhaps in the case of planetary nebula (I believe most of > these are not from cataclysmic doubles), that there is nothing to see until > the "life" of White Dwarf is turned on, to illuminate the gases expelled > from the red giant. Simply the intermediate period is before the nebula is > visible. Again, I imagine most white dwarfs are not the product of double > star systems gone wrong. > > _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com No virus found in this incoming message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.13/1914 - Release Date: 1/24/2009 8:40 PM No virus found in this outgoing message. Checked by AVG. Version: 7.5.552 / Virus Database: 270.10.13/1914 - Release Date: 1/24/2009 8:40 PM _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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Re: [Utah-astronomy] White dwarfs and YOU
by zaurak＠digis.net 25 Jan '09

25 Jan '09

Chuck, I imagine a black dwarf would be very difficult to observe, he must think the Universe is very young. I think there was mention that some planetary nebula gases are excited enough by a "very cool white dwarf" (they have a wide range of temperatures) that can't be observed, hence its a "black" dwarf. In essence some nebulas outlive (or at least cease to exist at the same time of) the white dwarf. Her explanation was that it is the heat from the white dwarf that illuminates the nebula. As Dan has pointed out amateurs commonly have the need equipment to see white dwarfs in nebula, but to see difficult companion stars not so much. You also mention that he is talking about white dwarfs from cataclysmic double stars. Perhaps in the case of planetary nebula (I believe most of these are not from cataclysmic doubles), that there is nothing to see until the "life" of White Dwarf is turned on, to illuminate the gases expelled from the red giant. Simply the intermediate period is before the nebula is visible. Again, I imagine most white dwarfs are not the product of double star systems gone wrong. Erik --- chuck.hards(a)gmail.com wrote: From: Chuck Hards <chuck.hards(a)gmail.com> To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] White dwarfs and YOU Date: Sun, 25 Jan 2009 19:17:50 -0700 Yes, the pressure remains constant, independant of temperature, as does gravity, which is dependent on mass; the dwarf stays the same size as it cools. As to why the star continues to shine post-fission, here is Bishop's explanation: "Because of their immense thermal energy and small surface area, white dwarfs cool extremely slowly. The universe is not yet old enough for any white dwarf to have cooled sufficiently to become a "black dwarf"." He continues, "Also, white dwarfs are intrinsically very faint; thus only those close to the solar system can be seen. *Only one white dwarf is easily observable with a small telescope*." This supports the idea that for distant white dwarfs that are part of cataclysmic binary systems, it's the infalling matter that is seen and not the dwarf itself. But, like Kim I'm curious as to the details of the intermediate stage between the formation of the planetary nebula (the asymptotic giant star throwing-off its outer atmosphere), and true "white dwarf" status, after the nebula has faded. It could be that fusion doesn't turn off quickly, but slowly peters-out, in fits and starts, during the same time-frame as the lifespan of the nebula itself. I wonder... All the argument about the definition of "easily observable" and "small telescope" is superfluous and unnecessary, especially when we begin bringing things like averted vision into the argument. On Sun, Jan 25, 2009 at 6:14 PM, <zaurak(a)digis.net> wrote: > Kim, I am quoting from the article I posted earlier. > > "Under the extreme conditions which prevail within a white dwarf, the laws > of quantum mechanics become important. Quantum mechanics is the study of how > subatomic particles (such as electrons, protons, and neutrons) behave. > Subatomic particles do not always obey the same laws as large objects. > Hence, the laws of quantum mechanics sometimes seem contrary to common > sense. > > One rule of quantum mechanics (known as the Pauli exclusion principle) is > this: > Two identical electrons, located in the same region of space, cannot have > the same velocity. > In a dense white dwarf, where the electrons are packed close to each other, > some of the electrons are forced to have high velocities, and hence provide > a high pressure. In a degenerate object such as a white dwarf, the > fast-moving high-energy electrons provide a pressure which is independent of > temperature. Even as the temperature of a white dwarf falls toward absolute > zero, the Pauli exclusion principle demands that the high-velocity electrons > keep moving at the same speed. Hence, the pressure exerted by the electrons > remains constant as the temperature falls." > > > _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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Re: [Utah-astronomy] White dwarfs and YOU
by zaurak＠digis.net 25 Jan '09

25 Jan '09

Or that we know very little about the "true" nature of the Universe. Theory should match observation, I suspect a few thesis needed to defend why their observations did not match current theory. --- chuck.hards(a)gmail.com wrote: From: Chuck Hards <chuck.hards(a)gmail.com> To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] White dwarfs and YOU Date: Sun, 25 Jan 2009 20:40:57 -0700 Erik, read my last post. You are assuming that stars that evolve into white dwarfs formed from the universe's first poplulation of stars. I'm not so sure. On Sun, Jan 25, 2009 at 8:38 PM, <zaurak(a)digis.net> wrote: > > > That was what the professor form Ohio States' Astronomy Department stated. > Again I am no Phd, but Perhaps the idea that the Universe is 13.5 billion > years old needs rethinking or perhaps that it takes 13 billion years for > white dwarfs to exhaust themselves, I read mention that in some cases it > takes 2 billion. > > > _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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Re: [Utah-astronomy] White dwarfs and YOU
by zaurak＠digis.net 25 Jan '09

25 Jan '09

What did they value it at? Did they know who John Bevis was? --- chuck.hards(a)gmail.com wrote: From: Chuck Hards <chuck.hards(a)gmail.com> To: Utah Astronomy <utah-astronomy(a)mailman.xmission.com> Subject: Re: [Utah-astronomy] White dwarfs and YOU Date: Sun, 25 Jan 2009 20:25:19 -0700 Coincidentally, on Antiques Roadshow tonight, they displayed a page from a Bevis star atlas. On Sun, Jan 25, 2009 at 8:20 PM, Jim Gibson <jimgibson00(a)yahoo.com> wrote: > Yeah, > Wikipedia says: > The Crab Nebula was first observed by John Bevis, and corresponds to a > bright supernova recorded by Chinese and Arab astronomers in 1054 > > > _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy(a)mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://gallery.utahastronomy.com Visit the Wiki: http://www.utahastronomy.com

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