 Hubble Deep Field -image courtesy NASA In this article, I will discuss the subject of Stellar Magnitudes. The magnitude system is very old, developed by the Greek astronomer, Hipparchus, (c. 190 - 12O B.C.) In these ancient times, stars were classified by how bright they appeared to human eyes, since many centuries would pass until the invention of the telescope and more sophisticated astronomical instruments. The brightest stars were called "first magnitude," the next brightest "second magnitude", all the way to "sixth magnitude," the limit of the unaided eye. We now call such descriptions apparent magnitudes, because they compare how bright different stars appear in our skies. Professional astronomers also employ a system of absolute magnitudes, which describe the luminosity of a star, which is the actual power output of that star. For the backyard amateur astronomer, knowing the apparent magnitude is enough for our purposes. In our time, the magnitude system has been further refined. A difference of five magnitudes represents a difference in brightness of exactly 100, so a magnitude 1 star is 1OO times brighter than a magnitude 6 star. Notice that the system seems to work backwards; that is, the higher the number, the dimmer the star. That's just the way it was defined all those years ago, and it stuck! Modern star charts or atlases often designate magnitudes by the size of the dot or circle representing the star, with an accompanying key.  Sirius -image courtesy NASA It was recognized, as time has gone by, that some objects have apparent magnitudes of zero or minus numbers, such as the brightest star in the night sky, Sirius, with an apparent magnitude of about minus 1.4. That is because they are brighter to our eyes than the originally-defined plus 1 to 6th: magnitude stars. An extreme example of minus magnitude objects is our own star, the Sun, with an apparent magnitude of minus 26.7. Going in the opposite (or dimmer) direction, the Hubble-Space Telescope has imaged distant objects with an apparent magnitude of plus 30 !  The "Seven Sisters" Pleiades - Wikipedia One way of testing your ability to see stars with the unaided eye is to view the Pleiades (or Seven Sisters) open star cluster (a group of stars that were all born about the same time), which may contain 500 stars. However, depending on light pollution, the visible naked eye number may be as low as 4 or 5 stars, perhaps up to 1O or more in dark skies. Most of the time, only 6 can be reliably seen. So, why the "Seven Sisters"? An ancient myth says the seventh Sister was kidnapped by Mizar, one of the seven "brothers" of the Big Dipper asterism. The brightest star, Alcyone. in the Pleiades, has an apparent magnitude of plus 2.9 . The cluster is still visible in early March in the western sky, about 9:00 p.m., near the constellation Taurus. References: May you have clear skies!! George Drake, M.D. ETHOS Innovation Center Volunteer, Michiana Astronomical Society Member
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  Image source: NASA Go outside about 9:00 p.m., weather permitting (cloudless night), early February, and look directly south. There, you will behold the most easily recognizable winter constellation, Orion, the Hunter. In Greek mythology, Orion was a gigantic hunter and is mentioned in Homer's Odyssey and Iliad and other Greek writings. He was described by several other historic world cultures, with rich mythic stories to describe his heavenly origins. He is mentioned three times in the Bible. Orion's form is that of an hourglass asterism. An asterism is a pattern, or group of stars that may outline a constellation, such as Orion, or be part of a larger constellation. The Big Dipper is an asterism in the constellation of Ursa Major (the Great Bear), for example. Orion straddles the celestial equator, so it is visible in both the Northern and Southern Hemispheres.  Image source: Wikipedia Four stars, Rigel (the sixth brightest star in the night sky), Betelgeuse (the ninth brightest), Bellatrix and Saiph, outline his upper and lower body. Betelgeuse is Orion's right shoulder, Bellatrix the left shoulder, Saiph the right foot, Rigel the left foot. Each of these four stars are giant, or supergiant stars. (We'll discuss star sizes and masses in a later article.) Orion's "Belt" lies in the center of the asterism and consists of threeEars: Alnitak, Alnilam and Mintaka. These are all supergiant stars. Hanging down from his belt is Orion's Sword, a pattern of three stars. The middle "star" is not a star at all, but is the Great Orion Nebula. Here, although some gas covers the entire constellation, it is 'unmasked' in the Orion Nebula by the incredibly intense light of young, hot stars. In other words, we are looking at a stellar nursery. Some of these stars are only a half-million years old, which in astronomical terms are infant stars. With good eyesight, you can see the nebula without the aid of a telescope. In my experience, it looks like just a slightly "fuzzy" star. Obviously, a telescope brings out details, with its wispy, ghostly form taking on ever greater beauty as the telescope aperture is increased. All stars form from the effects of gravity on clumps of gas and dust between the stars (interstellar gas and dust). Compared to the rest of the Hunter's body, the head of Orion is a tiny triangle of three stars. The topmost star of the triangle (Meissa) is also a giant star. I should- probably mention that these stars are called "giant" or "supergiant" because they are so much bigger than the Sun, our closest star. Nevertheless, they still appear as tiny points of light to our unaided vision, or even in large telescopes, because they are so far away! Once you recognize this beautiful winter constellation, you are not likely to forget it. A planisphere can help you locate objects in the night sky, like Orion, without the need of a computerized (GoTo), or clock-driven (equatorial-mounted) telescope, and they are inexpensive. Next time, we will talk about magnitude scales. a way to classify stars by their brightnesses. References: Advanced Sky Watching Bunham, Dyer, Garfinkle, George, Kanipe and Levy. Time-Life Books 1997 Backyard Guide to the Night Sky Schneider, H. National Geographic 2009 The Night Sky (trademark) Planisphere (for 40 - 50 degrees north latitude) David Chandler Company 2014 365 Starry Nights Raymo, Chet Fireside 1982 Wikipedia (search) 01/13/2021 George Drake, M.D. ETHOS Innovation Center Volunteer Michiana Astronomical Society Member
  This article will attempt to shed some light on the complicated subject of optical lenses, particularly, those used in astronomical instruments. I will discuss the science involved and then describe application for telescopes used in “backyard” astronomy. Lenses are designed to take advantage of what happens to light when it hits curved surfaces. Because light consists of electromagnetic waves (tiny electric and magnetic fields), it interacts with the tiny fields that are also found in matter. When light, traveling in the vacuum of space in a straight line, hits something else (like earth’s atmosphere), it slows down as it interacts with the tiny fields composing the material it hits. This process results in bending of the light, or refraction (that’s why the sky is blue). If you recall the first two articles in this series, one of the three telescope types I discussed, namely the refractor, utilizes this property of light exclusively. The reflector and catadioptric scopes depend on mirrors and lenses (in their eyepieces) as well, to create a magnified image for our eyes to transmit to the optical lobes of our brains, where the “seeing” will actually occur.  A lens is a transparent object (a disc of glass) that makes an image it takes from an object that is a source of light rays. It has curved surfaces that take advantage of refraction, to the extent that all the light rays entering the lens can all be brought to the same place, called the focal point, or focus. When the image is focused for our eyes, it can be magnified by a second lens (known as the eyepiece). The amount of magnification can be controlled by the focal length of the eyepieces. The focal length is the distance between the lens and the focal point, usually designated in millimeters (mm.) Because of the physics of light and lenses, the shorter (lower millimeter number) the focal length of the eyepiece, the higher the magnification. In practice, astronomical lenses are never quite this simple; as multiple lenses are often combined in eyepieces to improve the quality of the observed images. Refractor scopes depend entirely on lenses in the main body of the telescope as well as in the eyepieces. The cost of this type of equipment to the consumer increases as the scope’s aperture increases, due to costs of manufacturing larger and larger lenses. With refractors, the cost is also related to correcting errors (or, aberrations) in the lenses that are natural, or inherent properties of glass. Those aberrations can interfere with the sharpness of the image (especially at the edge of the image).  Another practical point regarding magnification and eyepiece focal lengths is this: as the magnification increases by using lower (shorter) focal length eyepieces, a point is reached at which the focus (sharpness) of the image begins to diminish, because you are magnifying everything between the end of the telescope and the sky object you are observing (turbulence in the atmosphere, dust, light pollution, etc.,). In addition, our eyes also have limits to their ability to resolve smaller and smaller details.
Next time, Orion, the Hunter, a beautiful Winter “object”. May you have clear skies! George Drake, M.D. ETHOS Volunteer Michiana Astronomical Society Member References: Physics II for Dummies Holzner, Steven Wiley Publishing, Inc. 2010 astrofarmfrance.com ( Searched 11-11-20)   ETHOS Innovation Center is proud to announce a $170,000 grant award by the Community Foundation of Elkhart County. The funds will support Science Technology Engineering Mathematics (STEM) activation in all schools in Elkhart County and beyond. The grant allows ETHOS to expand professional development programming, including the hiring of a new Director of STEM Education position to provide auxiliary support to area schools in science education, inquiry-based curriculum, and educator resources for teachers.
To meet the needs of a growing demand for STEM-skills related jobs, ETHOS has partnered with the Community Foundation of Elkhart County to deploy subject-matter experts to develop professional development programming, reinforced by evidence-based learning materials like Science Kits and e-learning modules to elevate STEM literacy in our community, and our region. We are confident the investment in top of mind, subject matter expertise in inquiry-based, argument-driven teaching methodologies are key to advancing STEM education and elevating our local talent as the future workforce. The staff and leadership of ETHOS Innovation Center are grateful to the extraordinary leadership and foresight of the Community Foundation of Elkhart County for investing in the future of our community through STEM Education and skills-based training to support the jobs of tomorrow. As a result of these special funds, and the generous support of our wonderful donors, we are proud to announce the following positions will be added to our team: Director of STEM Education and Science Teacher. If you or someone you know are qualified and interested in fulfilling our mission, please refer to the job descriptions for information on applying. We are so grateful to the Community Foundation of Elkhart County and grateful for our donors who are contributing to our year-end fundraising efforts through the Full STEM Ahead campaign to make this happen. If you have not yet contributed, we urge you to join this movement and make a year-end gift toward this initiative during this season of joy and giving.  Educational gifts and specifically, ones focused on developing S.T.E.M. (science, technology, engineering, mathematics) knowledge are not only great surprises to unwrap but can also play a large role in the development of your child.
Toys that focus on shapes, puzzles, and open-ended, active play help children develop important skills that help them later down the line when they are encountering complex concepts like math or science. ETHOS hand-selected a list of the top 28 S.T.E.M gifts for the curious young minds in your life: Book "How to Survive Anything" $12This illustrated guide teaches your child how to navigate some of nature’s wildest experiences like volcanoes, tornadoes, or even thin ice. The group at National Geographic created this book to help young adults face any obstacle. 3-D Engineering Puzzle $40This precisely made, laser cut wooden engineering set is the DIY kit to look into for some hands-on work with mechanical concepts like gears and interlocking mechanisms. Rainbow Nesting Puzzle $17This rainbow jigsaw is ideal for toddlers and kids being introduced to colors, shapes, and sizes for the first time. This puzzle cultivates imagination and helps your child take the first step into thinking abstractly. 6 Space Explorer Craft Projects $26Made for kids that are interested in the world beyond our planet Earth. This space explorer kit touches on our solar system, constellations, and rockets as well as many other fun space topics. Clean Science Mini Water Filtration $14Contribute to your child’s understanding of chemistry and the environment with this clean water science kit. This kit teaches your child the basics of water filtration and desalination. National Geographic Mega Gem and Fossil Kit $25National Geographic’s home learning kit for budding archaeologists includes 15 real fossils just waiting to be excavated by your curious scientist. Potato Clock Experiment Kit $14Bring science into the kitchen with this experimental kit that teaches children the power of green science. Spend the afternoon building clocks from grocery store potatoes and challenge your child’s imagination. Book "Awesome Science Experiments for Kids" $12For those with kids that are always exploring, this book covers over a hundred experiments and goes in-depth as to why and how they work. Written with step-by-step instructions, this book is easy for kids to follow along with and conduct experiments of their own. Water Rocket Kit $21Teach your child about the power of water pressure with this bottle rocket kit. This is especially great for those interested in space flight and engineering. Solar Thirsty Plant $6This kit helps kids make sensors that will let them know when their plant needs water and introduces them to concepts of solar power and electrical circuits. Mechanical Robot Coding Kit $35This is a great starter robot for young engineers who are just getting into the world of design and coding. This robot is capable of kicking, drawing, and throwing, making it a rewarding project for first-time engineers. 800-Piece Construction Straws $35This construction toy comes with 800 modeling pieces and connectors that help kids build upon their construction skills and creativity. Binoculars $17Compact, waterproof binoculars help your child explore the world around them. Non-slip grip keeps it safe in your kid’s hands while the design allows your child to see objects from 100 yards away. Book "Paper Airplanes" $15This book explores different paper airplanes design that your child can create with plenty of extra paper and clear instructions to walk them through each design. Marble Run Set $26This interactive toy challenges kids to think about shapes and directions by having them build race tracks for their marbles. It’s great for teaching logical thinking and hand-eye coordination. Wooden Geoboard $22A great toy and tool for practicing fine motor skills and visual skills, this wooden geoboard gives your child the option of piecing together pre-designed patterns or the freedom to make their own creative shapes, letters, or designs. Brain Teasers Jigsaw Block Puzzle $10This jigsaw puzzle is a real-life game of Tetris for your children to experiment with. Fit the pieces together to fill the surface or let them create their own designs. LEGO Chain Reactions Kit $19This set of moving balls, modules, and string takes LEGO pieces to the next level. Get your child’s thinking cap on through building moving machines. Snap Circuits Exploration Kit $54This circuits kit helps your child explore the world of physics. Using wires, switches, resistors, and capacitors, your child can build fun, working projects like lamps, radios, and many others. Hand-Operated Drone $30This drone uses infrared sensors to avoid running into obstacles and is controlled completely by your hands. It changes direction based on the placement of your hands and can be flown in a variety of settings. Suspend Family Game $14This family-friendly game is perfect for developing hand-eye coordination, cognitive skills, and interpersonal skills. This balancing game helps children with important developmental skills. Flakes Interlocking Building Blocks $17These building blocks are a creative and educational alternative to traditional building block sets. Brain Flakes can be used to build plants, cars, and animals simply by connecting pieces together. Physics Laws Building Set $26This kit helps kids explore the laws of physics through six experimental assemblies. Walk your kids through theory testing and physical concepts and help turn complex concepts into fun and educational experiences. Vehicle Building Toy $23Aimed at teaching kids knowledge while developing their S.T.E.M. skills, this vehicle building toy comes with a variety of builds that challenge and excite the most innovative of learners. Bridge Structure Construction Model $33This structure kit comes with nine building models that teach kids all of the facts and theories behind bridges and why they are able to work the way they do. These models let them explore the science behind bridge building and the forces supporting massive amounts of weight. AmScope Metal Body Microscope $90This set helps kids investigate the microscopic world around them and includes brine shrimp eggs that let them observe the life cycle of tiny ocean creatures. Fisher-Price Code-a-Pillar $35This caterpillar is an early learning tool for future coders and computer geniuses. There are 1,000+ different combinations for caterpillar’s movement, making for hours of visual, audio, and mental stimulation. Construction and Engineering Building Blocks $30This construction and building set covers a wide range of basic tools like nuts, bolts, and wheels and uses your child’s imagination to create different tools while using logical thinking and engineering skills.  For this article, I'm turning our subject from instruments to look at the sky, to the sky itself, for a very special event. More specifically, to the planets Jupiter and Saturn.
On December 21,202O, about forty-five minutes after sunset, the two planets will stand about 14 degrees above the southwestern horizon and will appear to be much less than 1 degree apart in the sky! Your pinkie-finger, held up against the sky at arm's length, is 1 degree, and the span between your pinkie-finger and your pointer (index finger) is roughly 15 degrees, again with your outstretched arm held against the sky That's not far above the horizon, so you might want to find a spot with a clear view of the horizon (around Michiana, Lake Michigan would be an ideal spot, weather permitting). This celestial event is known as a conjunction (more precisely a non-solar conjunction, since neither of the objects is the sun). Two non-solar objects are in conjunction if they have the same Right Ascension. Right Ascension corresponds to longitude on earth, but instead is reckoned on the celestial sphere. Another term for locating objects in the sky is Declination, which corresponds to latitude on the earth. Through a telescope at moderate magnification, both Jupiter and Saturn (and their brighter moons) will fit into your eyepiece's view. According to one Steve Albers, the last conjunction of these two planets that was closer and readily observable occurred in the year 1226, (nearly 800 years ago). Of course, though they appear so close together in the sky, they are, in fact, about 4O3 million miles apart. Jupiter orbits the sun at an average distance of 484 million miles and takes about twelve years to go around the sun once, and Saturn averages 887 million miles from the sun and its orbit around the sun takes about 29 1/2 years. So, though they are physically separated in space by nearly a half- billion miles, they still line up in the sky visually "every once in in a blue moon" (oops, the Moon's not involved!). Happy Holidays!! George Drake, M.D. ETHOS Volunteer Michiana Astronomical Society Member References: 1. Observer's Handbook 2O2O The Royal Astronomical Society of Canada 2. The Backvard Astronomers Guide 3.d ed. Dickinson and Dyer, Firefly books 2008 3. Solar Slzstem: A Visual Exploration Of The Planets. Moons. And Other Heavenly Bodies That Orbit Our Sun Chown, Marcus, Black Dog and Leventhal Publishers, Inc. 2016 4. Sky and Telescope American Astronomical Society Vol 140, No.6, December, 2O2O Learn more about conjunctions at 1 Degree of SkyTime: https://youtu.be/DILtQlBPF_4  In my first article on telescopes (see ETHOS September, 2020 E-Newsletter), I stated: “There are many things to consider when contemplating the purchase of a backyard telescope, not the least of them, the cost (in dollars).” In this article, I will make the argument that just going out and buying a “department store” telescope is not the best value for your money and might even turn you off to the hobby. Kids often receive these relatively inexpensive scopes as Christmas/Holiday gifts, so, if you are contemplating such a purchase, read on!  The typical department store telescope is often advertised as having extraordinary magnification power. As explained in the September, 2020, article, aperture of the scope (light-gathering power) should be the focus (pun-intended) of your investment, because you are trying to see (relatively) dim objects in the sky. Additionally, the mount for the scope is another investment to consider, since a good scope can be rendered useless if mounted on a rickety altazimuth or equatorial mount(see explanation to follow) that shakes or wobbles in the slightest breeze. At this point, let me make another pitch for attending a meeting of (or joining) your local astronomy club. There, you will find a wide range of experience in the hobby, from novices to seasoned veterans (who often own several types of scopes, may have built their own scopes, and, importantly, learned from beginners’ mistakes). Most club members love helping people new to amateur astronomy. In the remainder of this article, I will delve a little further into what you can expect in different price ranges for scopes and mounts. A telescope in the range of $150.00 to $450.00 (some reflectors, some refractors) will get you started. These include 4.5 to 6-inch reflectors and 70 – 130 mm refractors, which will allow reasonable views of the moon, planets and the brighter deep-sky objects. Some of these may offer GoTo (computerized) control, but for the same money, you can get more aperture with a non-GoTo scope. Purchase a good star atlas and learn to “star-hop” (by learning the constellations that contain the stars). For approximately $500.00 and up, “the sky is the limit” in terms of scope type, aperture and accessories. The catadioptrics mentioned in my first article, increase the price at each aperture level.
A quick lesson in mounts: Most beginner scopes come with an altazimuth (alt-az)-type mount (“alt” for altitude and “azimuth” for movement in a circle, following the horizon) [left-above]. Basically, they allow for up-and-down and turning movements. The Dobsonian-type mount is also an altazimuth mount [center-above], but much cheaper to buy, or construct, allowing for more aperture at each price point. German Equatorial-type mounts [above - right] are more complicated (thus, more expensive) and allow tracking of objects as the sky (actually, the earth) turns, without having to move the scope by hand. Each of these types can be purchased with computer (GoTo) controls, but at added expense and the missed opportunity to learn the sky!
May you have clear skies!! References: The Backyard Astronomer’s Guide 3rd ed. Terence Dickinson and Alan Dyer, Firefly Books, 2013 George Drake, M.D. ETHOS Innovation Center Volunteer Michiana Astronomical Society Member
 The Ecliptic is the apparent yearly path of the Sun and the approximate path of the Moon and planets. The ecliptic is tilted at an angle of 23 1/2° degrees from the celestial equator and intersects the equator at two points called the "equinoxes" (see diagram). The Sun passes the equinoxes around March 21 and September 21. This year (2020), the Spring or "Vernal Equinox" occurred on March 19. This point in the sky is called the "First Point of Aries," but is now actually in the constellation of Pisces. The "Autumnal Equinox" will occur at 9:31 EDT (1331 UT, or "Universal Time") on September 22, 2020.
My hope is that these astronomical offerings will interest youth in STEM and participation in our local opportunities, such as ETHOS and MAS (Michiana Astronomical Society). George Drake, M.D. ETHOS Volunteer MAS Member Sources: Burnham's Celestial Handbook, 1978 Dover Publications Observers Handbook 2020 The Royal Astronomical Society of Canada   A telescope is a tool for observing objects in the distance, either in the sky or across land and sea. In this article, we will talk about telescopes for observing objects in the sky, to their natural beauty and to understand more about the nature of the universe in which we live. It is useful to think of telescopes as "light buckets", whose main purpose is to gather as much light from a particular region of the sky as possible and to b.ing it into focus. For backyard astronomers, we are interested in observing sky objects in wavelengths visible to the human eye, that is, with an optical telescope (there are telescopes which observe other forms of light radio waves, microwaves, infrared, ultraviolet, x-rays and gamma rays, used by professional astronomers.). There are two basic types of optical telescopes: reflectors and refractors, that are used by backyard astronomers. A third type, known as catadioptric combines the two. To keep things simple, a reflector uses a curved mirror to collect the light and bring it to a focus at an eyepiece (see first figure at top of page). A refractor uses a lens, or a series of lenses, to focus the light at the eyepiece (see second figure at top of page). Combining the two types allows for a more compact telescope (shorter tube), but is a more expensive option (see figure at bottom of page). There are many things to consider when contemplating the purchase of a backyard telescope, not the least of them, the cost (in dollars). For those interested in buying a telescope that is worth the expense, I refer you to the references at the end of this article. A basic principle is to use your money on aperture (the size of the light-gathering mirror, or lens), rather than on magnification: seeing dim objects in the sky depends upon how much light is gathered. There are natural limits to magnification-at a certain point details, or resolution. exceeds the limits of the telescope equipment and our visual equipment (our eyes). May you have clear skies! [References: Night Watch: A Practical Guide to Viewing the Universe Revised 4*' Ed. Terence Dickinson Firefly Books 2013 (Basic) The Backyard Astronomy's Guide 3'd Ed. Terence Dickinson and Alan Dyer Firefly Books 2013 (More Advanced) George Drake, M.D. ETHOS Innovation Center Volunteer Michiana Astronomical Society Member  |
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