Affiliated with ReflectionsReflections The Newsletter of the Popular Astronomy Club ESTABLISHED 1936 February 2021 President’s Corner February 2021 the speed of light, this means the object is Welcome to the Febru- trapped in the black hole. ary edition of Reflec- The escape velocity for a planet is the speed at tions. We are in the which an object (like a rocket) would have to middle of winter, which be launched from the surface of the planet so should be obvious to that it would fly up and completely escape Page Topic everyone and especially from the planet and never fall back down for astronomers. We again. A rocket could orbit a planet at a slightly 1-2 Presidents have had very few op- slower speed and never fall back to the Corner Alan Sheidler portunities to view ce- planet’s surface, but in that case, the rocket 2-4 Announcements lestial objects and when would not have escaped, it would have been 5-10 Contributions we have, it has been too cold or snowy for trapped in an orbit around the planet. 11 Astronomy in most of us to get out under the stars. Print We can calculate the escape velocity for the For many of us, this is a time when we take a 12-13 Skyward Earth and other solar system objects using the vacation from observing and do other things 14 Upcoming Events fairly simple equation below. For those of you (like buy new telescopes or plan observing 15 Sign-Up Sheet not wanting to bother doing the math, I creat- sessions when the weather improves this 16 Astronomical ed the following table showing the escape ve- spring). For me, this is the time when my Calendar of locities for several solar system objects. mind gets to wandering. Events Earth’s escape velocity is slightly more than 17 Sky Views Over the last couple weeks, I became inter- 25,000mph (11.18km/s). Recall in 1968, Apol- 18 Planetary ested in black holes and in particular, about lo 8 reached this speed in order to escape from Alignments the size of black holes. In reality, a black Earth to reach the Moon. The escape velocity 19 Deep Sky hole is simply an object that has a gravita- for the Sun is nearly 1,382,000mph (618km/s) Wonders tional field strong enough to curve nearby and for Deimos (one of the two Martian 20 February space so drastically that nothing, not even moons) it is only 14mph. If you are a fast run- Night Sky light, can escape. It is difficult to imagine ner, you could escape from Deimos simply by 21 Golf on the how strong gravity has to be for this to hap- running! Moon pen. But essentially light is affected by gravi- 22 Spotlight I won’t bore you with the math, but if you are ty in the same way that physical objects are. 23-24 Landing on Mars good with algebra, you can solve the escape 25-29 News Links So, if one could shine a light beam up from velocity equation for r. Using the velocity of 29-41 Member the “surface” of a black hole, the beam light for the escape velocity and solving for r, Observations would eventually be curved back down by you can find the size of a black hole corre- 42 Paul Castle the black hole’s gravity. Simplistically, we sponding to any planet’s (or star’s) mass. The Observing can think of a black hole as having an escape radius r of a black hole is called the Schwarz- Sessions velocity equal to or greater than the speed schild Radius. For the Sun, this is just under 3 43 January Meeting of light. The “surface of the black hole” in km. In other words, if you could crunch the this case is a boundary known as the event Sun down to less than 6 km in diameter, it horizon. If anything passes inside the black would be a black hole! hole’s event horizon, that object would have It would take a lot of pressure to do that! In- to travel faster than the speed of light to be terestingly, if you could compress the earth able to escape and since nothing can exceed (Continued in next column) (Continued on next page) 1 (Continued from previous page) ANNOUNCEMENTS / INFO Popular down to the size of a penny, it would also be Astronomy a black hole! I’m not going to lay awake at NCRAL Club night worrying about this happening, but it Officers gives us a way to imagine the stupendous Seasonal density of a black hole. Messier PRESIDENT - Alan Sheidler Recently, astronomers were able to obtain Marathon 3528 56th Street Court, Moline, an image of the super massive black hole at Program IL, 61265 the center of super giant elliptical galaxy Phone: (309) 797-3120 M87. The mass of this black hole is estimat- NCRAL’s Seasonal Messier Marathon VICE PRESIDENT – Dino Milani ed at 6.5 billion times the mass of our Sun. I observing program is NOT designed 2317 29 1/2 Street, Rock Island, will leave the math to you, but if you do it, to qualify observers for the Astro- IL, 61201 you find the Schwarzschild radius of M87’s nomical League’s Messier Observing program; the two programs are unre- Phone: (309) 269-4735 black hole is 127 Astronomical Units (127 lated and observing requirements are times the Earth-Sun distance). That’s BIG! quite different. In the NCRAL pro- SECRETARY - Terry Dufek gram, the main requirement is to 2812 W. 65th Street, Davenport, Anyway, you see what happens when my quickly observe and essentially check IA, 52806 Phone: (563) 386-3509 mind gets to wandering. Let’s hope for a off items from one of four seasonal break in the weather and keep looking up! lists of Messier objects as noted in the section to follow. TREASURER – Dale Hachtel Al. 1617 Elm Shore Drive, Port Byron NCRAL recognition will consist a suit- IL, 61275 able printed certificate and a 3⁄4-inch Phone: (614) 935-5748 enameled star pin (a different color for each season). There will be no ALCOR – Roy E. Gustafson direct cost to the membership for participating in the award program; 11 Deer Run Road, Orion, IL, the cost of the program (pins, certifi- 61273 cates, mailers, postage) will be borne Phone: (309)526-3592 by the Region as a benefit of affilia- tion. Relevant program documents DIRECTOR OF OBSERVATORIES - are linked below Rusty Case 2123 W. 16th Street, Davenport, NCRAL Seasonal Messier Marathon Pro- IA, 52804 gram Rules Phone: (563) 349-2444 NCRAL WINTER Seasonal Messier List PAST PRESIDENT - Wayland Bauer NCRAL SPRING Seasonal Messier List 3256 Pleasant Drive, Bettendorf, IA., 52722 NCRAL SUMMER Seasonal Messier List Phone: (563) 332-4032 NCRAL AUTUMN Seasonal Messier List NEWSLETTER EDITOR - Terry Dufek 2812 W. 65th Street, Davenport, IA, 52806 Phone: (563) 386-3509 Contact for Information or questions here: This image of a black hole—the first ever popularastronomy- taken— was captured by an international [email protected] team of researchers in April 2017. The black hole in located in the center of Galaxy M87. 2 ANNOUNCEMENTS / INFO READY FOR MEMBERSHIP OR TO RENEW? LOOKING FOR OLDERLOOKING ISSUES FOR OF OLDER For PAC Documents REFLECTIONSISSUES OF REFLECTIONS Use NEWSLETTER?NEWSLETTER? “Enrollment Form” Click HERE HISTORY OF PAC? HISTORY OFClick PAC? HERE SUBMISSIONS If you have an article or photos to submit or Popular Astronomy Club items of interest, we encourage you to send Popular Astronomyon Facebook? Club them in by the 25th of the month. Links to on Facebook?Click HERE stories are welcome also. Thank you! Astronomical League Observing Programs The Astronomical League provides many different Observing Programs. These Observing Programs are designed to provide a direction for your obser- vations and to provide a goal. The Observing Pro- grams have certificates and pins to recognize the observers’ accomplishments and for demon- stratingstrating their their observingobserving skills skills withwith a avarie- variety of in- ty of instrumentsstruments and and objects objects Check out the Astronomical Click Here League ONLINE! Check out the North Central Region of the Astronomical League (NCRAL) online 3 ANNOUNCEMENTS / INFO Ever wonder Where New Horizons is right now and what it is up to ? 4 CONTRIBUTIONS Conjunction of Jupiter & Saturn, December 2020 You Tube Video by al Sheidler 5 CONTRIBUTIONS Make a Moon Phases Calendar and Calculator – NEW 6 CONTRIBUTIONS I wanted a close up picture of the Orion Nebula, so I went there in my Space Suit! Seriously, people can download an App called “NASA Selfies”, put themselves in a space suit, and chose a bunch of backgrounds and save the images. Might be something our members can do when they are home because of COVID-19. 7 CONTRIBUTIONS 8 CONTRIBUTIONS The habitable zone will move as the Sun ages. It will move so far that the Earth will not be in this zone in a few billion years. Jupiter and Saturn will be so, I am selling land deeds on some of their satellites now - buy now and avoid the rush and the price increase!! Contributed by Roy Gustafson (contact for purchasing info) 9 VIDEO CONTRIBUTIONS Some You Tube videos for you to view while being home bound Geminid Meteor Shower 2020 through the Northern Lights - real-time HD Interview: Is there life beyond Earth? I Left the City to Photograph the Andromeda Galaxy A Journey to the End of the Universe This Decade Will Be Remembered For Deep-Sky Astrophotography During a Full Moon? The Starlight Xpress Oculus all-sky camera These are the asteroids to worry about My CALIFORNIA NEBULA Project is DONE! (CANON EOS Ra) 10 ASTRONOMY IN PRINT SKYWATCH is closest to the sun Mercury s approximately 36 million miles from the sun.