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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...
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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...
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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...
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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...
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Physics Photo of the Week

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Physics Photo of the Week December 20, 2024  Galaxy M33 - Color photo by Donald Collins, College View Observatory Several weeks ago I published a monochrome image of the Galaxy M33 . The gray scale of astronomical photos are rather dull compared to the photos printed in color.  The color in astro photos also reveal much more about the physics of the astronomical objects - especially galaxies.  In this deep sky image of the galaxy that is several million light years distant from our planet Earth, all the discrete stars that we see in the image are foreground stars that exist rather close to us within our own Milky Way galaxy.  The billions of stars in the distant galaxy are so far away and so numerous that they blend together to resemble clouds.  Notice that the clouds of stars in the outer spiral arms of Galaxy M33 appear bluish, while the star clouds near the core of the galaxy are more reddish.  These colors mainly refer to the average temperatures of th...
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Physcis Photo of the Week

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Physics Photo of the Week December 6, 2024 Wake in clouds from mountain peak - satellite photos composed by D. Collins   The satellite image above shows the northeastern US in mid-winter (February 2024).  The left half of the image shows the many snow-covered lakes in the Adirondacks of northern New York.  The middle section shows snow-covered mountain ridges of Vermont that run north and south.  The mid right-center section shows a interesting piece of New Hampshire and a small gap in the clouds running southeast of a special white spot.  The white spot is the snow-capped summit of Mt. Washington breaking through the clouds and illuminated by the rising Sun. The zoomed-in image at right shows the effect.  Mt. Washington's summit, at 6288 ft. above sea level, is the highest mountain point in the northeastern US*.  The summit has p enetrated the cloud layer that was blowing towards the southeast.  The downstream part of the clouds show a wake in...
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Physics Photo of the Week

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Physics Photo of the Week November 22, 2024 Galaxy M33 - The Triangulum Galaxy The Triangulum Galaxy (M 33) is located in the Triangulum constellation fairly close to the more famous Andromeda Galaxy in the sky, and is about the same distance from the Earth (between 2 million and 3 million light years).  The Triangulum Galaxy,  is smaller (less massive) and fainter than the Andromeda Galaxy, but it appears more delicate and seems to show more discete clouds of stars and a number of large clusters in its spiral arms.   At right is a photo of the Andromeda Galaxy, but taken with a smaller focal length telescope.  The Andromeda galaxy covers a much larger proportion of the sky (about 3 degrees across) compared with the angular size of the Triangulum galaxy (about 1/3 degree across).  Short focal length telescopes show a larger field of view than long focal length telescopes, hence the Andromeda appears smaller than the Triangulum in these telephotos.  The...
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