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Physics Photo of the Week

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May 9, 2025 Open Star Clusters - Astrophotos by Donald Collins, College View Observatory   Throughout the Milky Way Galaxy there are thousands of open star clusters.  One of closest open star clusters is the Pleiades - or "Seven Sisters" - featured in the lower left photo.  The Pleiades cluster is the closest cluster from the Earth - 440 light years distant.  The bright stars of the cluster form a small "dipper" asterism.  Star clusters are groups of stars within the spiral arms of a galaxy and have formed from relatively recent condensations from clouds of gas and dust within the galaxy.  The Pleiades are about 100 million years old, which is fairly young for star clusters.  The stars were formed from the gravitational condensation of gas and dust clouds into several hundred stars.  The Pleiades is easily seen with naked eyes throughout late fall through mid spring.  They are visible now (late April) in the western sky about halfway between ...

Physics Photo of the Week

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Physics Photo of the Week April 4, 2025 Galaxy M106 - Photo by Donald Collins - College View Observatory Galaxy M106 - the 106th entry in Messier's famous catalog of deep sky objects - lies about 20-25 million light years from Earth.  It is about 10 times further than the Andromeda Galaxy and about twice as far away as the recently featured Galaxy M87 .     As with most galaxies, M106 contains on the order of 100 billion stars , and most likely has a supermassive black hole lurking deep in its core.  Celestial south is up in this photo. This galaxy is interesting in that there are many star-forming regions within the spiral arms.  It's also rather "clumpy".  The clouds of dust and stars are not very evenly distributed.  The clumps of new young stars are the clumps that appear brighter and "bluer" in the photo.  The clumps of stars eventually will dissipate and result in open clusters similar to the Pleiades (Seven Sisters) star cluster in our own...

Physics Photo of the Week

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  Physics Photo of the Week Total Lunar Eclipse of March 14, 2025 Moon Photos by Donald Collins The weather improved last week for an excellent viewing of the total lunar eclipse.  The Moon was totally within Earth's shadow between about 2:30 am to about 3:30 am.  The Moon takes on this reddish color when totally within Earth's shadow.  The animation below consists of three frames: 1-Near the beginning; 2-near the middle of eclipse; 3-near the end of the hour-long totality.  If you look carefully you can see two stars in the right half of the images.  The stars are stationary relative to the tracked telescope.  In the hour-long totality the Moon has moved approximately one radius relative to the stars as the Moon orbits the Earth.  The Earth's shadow also moves due to the Earth moving in its orbit around the Sun, but the Earth's shadow is much slower than the Moon's motion.  Unfortunately, I did not get any partial phases of the Earth's shado...

Physics Photo of the Week

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Physics Photo of the Week March 7, 2025 Galaxy M81 - Bode's Galaxy - photos by Donald Collins T his galaxy, near the Big Dipper asterism in the sky, part of Ursa Major constellation, is one of my favorite galaxies to photograph at the College View Observatory.  Not only does it illustrate the definite spiral structure, but it also shows the predominant blue colors in the spiral arms. The "bluish" arms contrast with the bright reddish color of the broad nucleus or core of the galaxy. Galaxies have been around in the Universe since very close to the creation of the Universe according to the Big Bang theory.  The James Webb telescope has imaged countless galaxies at red shifts very close to the speed of light. This large redshift indicates that these most distant galaxies are 12 billion light years distant.  That is about 90 percent of the believed age of the Universe.   Will there be an ultimate limit to the distance of galaxies? This galaxy, Messier 81 in the famous c...

Physics Photo of the Week

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Physics Photo of the Week February 21, 2025 The Horsehead Nebula (IC 434) - Photo by Don Collins - College View Observatory The Horsehead Nebula in Orion is a famous icon of deep sky astronomy for it's unusual well-fitting image of a horse.  It is also unusual in that it is a dark nebula -  a giant cloud of dust suspended in the cosmos - rather than a luminous nebula.  The size of the horse's head is about 7 light years across.  The head appears as an extension of a larger cloud of dust and molecules in the constellation Orion.   This color photo was obtained with the CCD camera on the College View Observatory telescope over a span of one week in late January, 2025.  The process involves taking about an hours' worth of pictures in one night for several nights during the week.  Each night would concentrate on a single filter eventually obtaining a stack of white light monochrome photos and a stack of each of the red, green, and blue filtered images...

Physics Photo of the Week

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  Physics Photo of the Week February 7, 2025 The Flame Nebula  (or the "Burning Bush") Astrophoto by Donald Collins - the College View Observatory   This is "The Flame Nebula" - an interstellar dark cloud surrounding by a glowing cloud.  I like to compare to the Burning Bush that is described in the Bible.  The burning bush in the Bible appeared to Moses - a bush on fire, but not burning up.  A perpetual flame.  This cosmic burning bush likewise is not burning up, but appears to last forever. Ancient stories aside, the cosmic flame is not the burning up of stars.  On the contrary, the "burning bush" trunk and branches are cosmic clouds of dust particles as well as hydrogen gas.  Stars are actually being formed deep inside the dark clouds.  The glowing cloud in the astrophoto above is about 6 light years across calculated from the field of view of the camera-telescope system (18 arc minutes) and the approximate distance of the nebula fro...

Physics Photo of the Week

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Physics Photo of the Week January 24, 2025 The Moon - Mars Occult - Photos by Donald Collins A week ago Monday (January 13, 2025) the Moon actually passed over the planet Mars in the Sky - visible from about all of North America.  This happened in the evening of full Moon.  In this week's photo we can see the image of reddish Mars about 30 seconds before the Moon completely covered Mars.  This is an occultation of Mars by the Moon.  This is a somewhat rare event that happens once in about 14 years visible from a specific location on Earth.  Events like this are not very spectacular - no major changes in the sky brightness as opposed as happens when the Moon is eclipsed by the Earth's shadow, or the even more spectacular occultation of the Sun by the Moon during a total solar eclipse!  Relatively rare events involving interactions of Solar System bodies with each other or with the stars attract enthusiastic astronomy "nerds".  Solar System bodies' orbi...