TGT #25I - Outreach in India - Measuring Light Efficiencies in your Neighborhood - Planet-Planet Conjunctions, & More!
TGT 6/1/25: TCA: Outreach Ideas on Seasons, Shadows, Spectra, Area Lighting; SPC: Two Planet-Planet Meetings, Moon-Star Meetings Galore.
Cover Photo - Zero Shadow Day (and Not Always the Solstice!)
In This Issue:
Cover Photo — Zero Shadow Day (and Not Always the Solstice!)
Welcome to Issue #25I!
TCA - Towards Cosmic Awareness —
* Astronomy Outreach Ideas from India (Cover Story)
* Measuring Area Lighting EfficienciesSky Planning Calendar —
* Moon-Gazing - The Moon Gets Ever Closer to Stars
* Observing—Plan-et - A Pair of Interesting Planet-Planet Conjunctions
Welcome to The Galactic Times Newsletter-Inbox Magazine #25I!
Greetings, Galactic Timers!
I’d like to say it was a month of rest after finishing up a book tour on the Marquis de Lafaytte….but rest would not be quite the adjective. One week in and I undertook an operation to fix a spine problem. Took three days to learn how to walk again, but hey, you always learn things quicker the second time around, right? Anyway, have reached a point where I can do SOME work each day, and rapidly improving on that.
In fact, my work time is now halved between an update to my existing Civil War historical travel book “Walking the Line” and TWO too-long-to-be-unfinished astronomy books. The first one of those is tentatively entitled “Learning Astronomy Under the Northern Stars” and is based on a set of 8 column-articles I wrote for the original color magazine The Classroom Astronomer (2009-2015). A possible subtitle is ‘The 365-Night Astronomy Resource Book.” But these eight columns (all still available in the individual issues, see https://www.classroomastronomer.com) will be updated somewhat, and will be augmented with about an equal number of extra “articles”, in book form. The idea is that to teach a variety of astronomical concepts at night you need those resources up in view no matter when your course or study takes place. January or July. The only such resources are (for most of you Readers of TGT) are the North Circumpolar Stars. Given appropriate celestial objects, one can learn about star brightnesses (magnitudes), angles and coordinates and constellations for locating them, astrophysics of stellar colors and spectra, galactic structure and objects beyond the rim, and stellar evolution, among many other topics. As long as they are visible whenever you need them, not just a particular month or season, this book will guide you.
I will start posting updates on this book, which I expect to come out in early Fall, in TGT but have not decided how yet.
Incidentally, these two new books, including one I did not describe above, are the first of a flurry of astronomy-related products, new and updated existing ones, that I expect to have out and available over the next twelve months. Stay tuned!
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The evening sky—pick a time and, except for an hour and a half in middle night, there are planets up, but mostly singly or duos. Two interesting pairings are Mercury and Jupiter passing each other in the low evening twilight, and a month-long pre-dawn conclave between Saturn and Neptune, with Neptune’s brightness-twin —Saturn’s moon Titan— nearby as well. See Observing—Plan-et.
The Moon has a parade of conjunctions, too, each one tighter than the previous one. See Moon-Gazing, both columns within the Sky Planning Calendar section.
Finally, ‘tis the season…..for online astronomy meetings. Just before this issue was sent out, yours truly attended a Global Science Communicators (Global SciComm) meeting and listened to a speaker from India talk about their public outreach in astronomy. 57,000 people in one year! I offer three activities or demos in an article from that group, and one of my own to go with them. See TCA. Articles based on material observed at two other upcoming big meetings will come in the next two months of issues.
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Enjoy!
Publisher — Dr. Larry Krumenaker Email: newsletter@thegalactictimes.com
TCA - Towards Cosmic Awareness
Astronomy Outreach in India
A group of astronomy educators, and science communicators, from India, the United Kingdom, Ghana, and the Netherlands met on Zoom for a Global SciComm Meeting to pass along information and advice. The two main speakers were a biology/environmental instructor for a public outreach group in Ghana, the other an astronomy outreach specialist out of the Inter-University Centre for Astronomy and Astrophysics of Pune, India, near Bombay (also called Mumbai).
That last person was Samir Dhurde, who talked about Low Cost and Large Scale outreach efforts. In terms of Large Scale, in 2019 they facilitated with 57,000 people! Still, that’s a small fraction of the 1.4 billion Indians. But they try to 1) “inculcate a science interest in students, especially the underprivileged, 2) Motivate talented students to take up science research, and 3) Inform the public and promote astronomy.”
The IUCAA offers traditional lectures, summer programmes, public visits. More interesting to Readers here might be what they do off their campus, with workshops for students, the public and teachers, mobile planetarium shows and outreach to the far larger population who are in rural sites as opposed to the cities.
Two activities among those for the outside campus projects that can be duplicated cheaply and outside of India follow here….
One is their annual Zero Shadow Day, where the southern half of India, which lies in Earth’s Tropical Zone south of latitude N. 23.5 degrees, put out common cylindrical objects to see that the Sun truly ON THAT DATE goes truly, really overhead and objects have no shadow. [See the Cover Photo.] Common objects used include toilet paper rolls and soda cans, mimicking the Syene wells that were reported to the ancient Greek scientists Erastosthenes as having no shadow and the Sun going straight down into the well this one day. In subtropical sites not at the Tropic of Cancer or Capricorn, there are actually two dates each year that this happens at those locations. Above the Tropic of Cancer, there are no such days. But…..
For those not in tropical zones the group sets up Least Shadow Days. This occurs on the Solstice, June 20, a date rapidly approaching! When possible they try to coordinate with a group outside of the Tropical Zone to reproduce Erastosthenes’ experiment and actually measure the Earth’s size.
The other activity is viewing spectra with a definitely “least cost” spectroscope, using a small box and a cut piece of excess CD or DVD disk. Having a narrow slit on one end and view door open on the other, spectra of various light sources can be observed by an auditorium-filled room of hundreds or even thousands at a time!
Also shown, an interesting way to show how white light is all the colors at once was done with bicycles, something very common in this most populous nation! The wheels spin, the colors disappear into a white reflection!
Find out more about their programs at their website, scipop.iucaa.in .
Measuring Your Area’s Light Efficiency
I believe that science demos should be more than just an academic learning experience. It should relate more to the real world. Let me contribute an example using spectroscopy, whether using Dhurde’s spectroscope boxes or just diffraction gratings. The above illustration comes from both a Classroom Astronomer Magazine article and an out-of-stock-for-now Hermograph product, one of two Spectrum Viewers with photographs of spectra on both sides and a built-in large-windowed diffraction grating. I developed these years ago; the other lets you identify gas tubes as found in physics or chemistry classes and is still available in the online Hermograph Press store (https://www.hermograph.com/store/product/elements-mixtures-and-molecules-viewer/).
In this exercise, the lights in an area are inventoried—how many fluorescents are visible, LED lights, regular tungsten bulbs, Mercury vapor lamps, etc. Use the spectra above to be sure you know what kind of light each one you see really is.
Then use the numbers on their individual energy efficiencies on the right-most column in the above table in the following manner:
(A) Multiply the TCA efficiency per lamp by the number of the lamps in your sample. [ Example, 10 incandescents → 10 x 10 = 100; 4 LEDs → 4 x 3460 = 13,840 ]
(B) Add all the (A) values for all the lamps together. [ 100 + 13840 = 13940 ]
(C) Multiply the TOTAL number of lamps seen by 3460. [ 14 x 3460 = 48440 ]
(D) Divide (B) by (C) and then multiply that by 100 to get your area energy efficiency value as a percentage. [ 13940 / 48440 = .288 (rounded) x 100 = 28.8% area’s efficiency ]
Many will find their area average is usually far less than 100%. When I did this when teaching, students made a report and gave their values to their schools. Other times it was done at home and we compared neighborhoods and reported this to the utilities to get better lighting and less light pollution.
If you use these photos please credit ©Hermograph Press.
Would you like Spectrum Viewer lighting cards with diffraction gratings built in to use for your classrooms? Hit this link to let us know YES and how many. If there is sufficient call, more will be produced again.
Sky Planning Calendar
Moon-Gazing
Moon passages by a star, planet or deep sky object are a good way to find a planet or other object if you’ve never located it before.
June 1 Two conjunctions today, 16 hours apart. First, Mars is found 1.3-degrees South of the Moon. Hours later, you’ll find the Moon 1.7-degrees North of the bright star Regulus. The first might be glimpsed with Mars low to the ground early the evening before, or on the other side of the Earth this day in their earlier evening hours. The latter is very much a North American evening event.
June 2 First Quarter Moon.
June 6 The bright star Spica is just one Moon-apparent-diameter (1/2-degree) North of Luna. But that’s not the closest the Moon gets to a star this fortnight.
June 7 Actually, the Moon will be slightly smaller than this average Moon size because tonight is the time of Apogee, when the Moon is farthest from the Earth this month. A Micro-Waxing Gibbous Moon anybody?
June 10 Antares wins! This star is not only a mere 0.3-degrees from the Moon’s edge here in the Northern Hemisphere but in Australia it is actually 0.0-degrees from the Moon, occulted, behind the Moon! Not sure about this red giant star? The Moon will be to the right of it on the 9th and to the left on the 10th.
June 11 Full Moon.
Observing---Plan-et
==It (Mercury) might be best spotted on the 8th when Mercury and Jupiter pass each other by 2-degrees and at nearly at the same brightness. Jupiter to the left (west and south of Mercury) is the brighter, at magnitude -1.8. Mercury will shine at magnitude -1.2. ==
==Planets widely spread, Mercury and Jupiter in the dusk, Mars in the evening, Saturn in the pre-dawn, Venus from the start of twilight.==
==Saturn (with Titan) has an easy close conjunction with Neptune.==
Mercury, especially for Southern Hemisphereans, is entering into a good evening appearance. For Northerners it will be visible all month but low. Being most easily visible when it is up in the sky 45 minutes or more after Sunset, start looking at that time after the 3rd of the month. It might be best spotted on the 8th when Mercury and Jupiter pass each other by 2-degrees and at nearly at the same brightness. Jupiter to the left (west and south of Mercury) is the brighter, at magnitude -1.8. Mercury will shine at magnitude -1.2. In fact, Mercury has a rare Double Greatest Brilliancy during an apparition, the first on the 1st and again on the 30th! It is all a matter of geometry and perspective, how close to Earth it is AND how much square area of lit-up Mercurian surface shines towards us.
That surface will be shining towards us until into July, but never too far from the Sun or horizon or in near-darkness.
Venus, having only recently been in solar conjunction, reaches its greatest distance-elongation from ol’ Sol, 46-degrees. Despite that, it rises only just barely before morning twilight begins, within 0 - 30 minutes before, depending on your date. It also is shrinking and getting fuller in phase so in a telescope it isn’t very impressive.
Earth begins is solstice period with a bunch of “earliests”. The earliest of those is on the 14th, with the earliest Northern Hemisphere sunrises. More in the latter part of the month.
Mars is the last planet glowing, after Mercury and Jupiter set. For an hour and a half on the 1st there will be no planets once Mars sets around 1:30AM Daylight Savings Time. That drops to an hour by midmonth, the end of the planet-free time being the rising of Saturn. Mars is closing in on Regulus, with both star and planet being near the Moon on the 1st. Star and planet are closest to each other just after this fortnight ends, on the 16th, when both are the same magnitude, +1.4, but of (hopefully obvious) different colors.
Brilliant and interesting Jupiter does it disappearing act now. It will be still be visible for more than 40 minutes after sunset only until the 11th, when it just gets too much lost in the evening twilight glow. Your last good chance to find it is in the LOW west-northwest horizon near almost-as-bright Mercury on the 8th and a few days either side. They pass two-degrees (4 Moon diameters) from each other, Mercury doing most of the passing, away from the Sun. Jupiter will reappear in the dawn twilight in about a month or so.
Saturn is the brightest night-time planet, and the only one up once it rises around 1:30 AM until just before dawn begins. Saturn, still close to ring-less, has an interesting conjunction this month….with Neptune. It passes about 1-degree from the farthest planet, the latter notably visible as a slightly greenish star and a very tiny disk in medium to high telescope powers. Both move so slowly that that distance hardly changes all month. Interestingly, Neptune is a faint magnitude +7.9 but Saturn’s brightest moon, Titan, nearby, is nearly identical at +8.3. At its farthest from Saturn’s disk, Titan is easily visible in even small scopes, such as a 2.4-inch refractor commonly available in stores.