TGT #25A - Meteor Hits Canada - Looking for Planets Like Us - Bucket Lists - Sky Event Calendar
TGT 1/17/25: TCA--Mars Occultation and Bucket Lists; This Just In--Meteor Strike Recorded on Camera; Odds of an Earth or Jupiter Around M-dwarfs; Sky Planning Calendar--Comet! Look QUICK or Go South!!
Cover Photo - Meteor (Not the USA) Attacks Canada, Recorded on Security Camera
In This Issue:
TCA-Sky Lessons: Observational Bucket Lists? Try the Occult(ations)!
Cover Photo — Meteor (Not the USA) Attacks Canada, Recorded on Security Camera
Welcome to Issue 25A!
Sky Planning Calendar —
* Moon-Gazing - All Quiet on the Evening Front
* Observing—Plan-et - The Last Month to See Four Bright Evening Planets; Look Fast For Comet ATLAS (A New One)
This Just In —
* Meteor Striking Patio Recorded on Security Camera (Cover Story)
* Looking for Earth-like Planets—Are We Actually Not Alone? , Part 1
Welcome to The Galactic Times Newsletter-Inbox Magazine #25A!
Greetings, Galactic Timers!
Hope your holidays were cosmic and you celebrated the New Year (whichever one you liked) responsibly. Coming back myself straight into the American Astronomical Society (AAS) meeting this week before a rapidly accelerating book tour, the last of three, this winter and early spring.
In this issue our Towards Cosmic Awareness (TCA) column Sky Lessons starts us on a series(?) of articles on astronomical bucket lists. What are the kinds of observational collections you can do to reach a milestone and learn things besides? We start with images of the Moon passing all planets, and planetary occultations—the Moon passing over a planet, Mars in this case. Your comments are welcomed!
The next two weeks are still filled with four bright evening planets though none of them do anything particularly dramatic, like the recent occultation of Mars. But this begins the last month where Saturn and its rings are NOT edge-on and we see the northern side of the rings—gone soon, for 14 years. See the Sky Planning Calendar, and while there get the info of the very brief but very bright comet to be seen in our evening sky up North, Southern Hemisphere observers get a better show. The comet starts at magnitude -3, nearly as bright as Venus, but here no better than 5 degrees from the just-set Sun.
This Just In reports on a near-Sylacauga ‘hit a person’ event in Canada, and from the AAS meeting with Part 1 of 2 articles on the search for planetary systems, and planets like ours.
- - - -
* Not a Subscriber? Want to read this on the Web? Please hit the link..right… below:
Enjoy!
Publisher — Dr. Larry Krumenaker Email: newsletter@thegalactictimes.com
TCA-Sky Lessons: Observational Bucket Lists? Try the Occult(ations)!
During the semi-hiatus of the holidays I took my own advice and tried to watch the Moon pass by, or over, the four bright evening planets: Venus, Saturn, Jupiter, and Mars in that order (and a bonus, the Moon over the Pleiades star cluster). The highlight would be the Moon occulting Mars.
First up was the Moon passing Venus on the evening of January 3rd, or more likely, during the day. I didn’t try to spot Venus with the naked eye 1.4-degrees from the Moon during daylight. I’ve done that, successfully, in the past, but with younger better eyes.
Cell phone photographing the Moon and Saturn, 0.7-degrees apart also during day hours—occulted in another part of the world—much wider during the next, early evening, was harder. But I collected a reasonable but not admittedly decent shot of the Moon East of dim Saturn and bright Venus to the west of the Ringed Planet. In my photograph it is one-fifth of the way from Moon to Venus and slightly to the left of that line.
Cloudy or rainy skies hid the Moon-Jupiter and Moon-Pleiades events.
But that Mars-Moon meeting was most spectacular. In this case, the photography was tried by both holding the cell phone up to the sky as before and up to the eyepiece of an old 2.4-inch refractor at a low power. Because of the proximity of the two objects and the lunar brightness compared to Mars, the before-no optics photo is poor, the dot below the overexposed Moon.
The view of Mars just emerged from behind the Moon in the telescope was, if not properly exposed for the Moon, still better. You might even detect the slight orange color in the photograph. It was DEFINITELY a round, small and distinctly orange disk to the eye when it popped out from the Moon’s edge.
Okay, it was fun but what’s the point here? How about making an astronomical bucket list? Or lists?
In this first case, occultations are common, especially for fainter stars or objects, but not so much for planets or bright stars. A bucket list can include a photographic series seeing the planets and photographing them or drawing them. Or the Moon passing by a planet, one by one. But another list could be catching the Moon OVER planets. With such observations you really get to see activity—motion—in the sky, something most normal sky views, like constellation collecting, don’t do. This is probably the first time I’ve seen Mars dance with the Moon, but I have memories of a Saturnian emergence—partially blocked by a dark lunar edge! I don’t recall any Jovian occultations but I might have seen a Venusian one, the twin crescent phases in view together. I’m going to keep a watchful eye for future occultations, to photograph them all, to complete the collection, adding in Mercury as well.
Such bucket lists need to be done over time, however. Years, even. This year 2025 has six planetary occultations: three of Saturn, two of Mars, and one of Venus. Only the recent Mars one is easily viewable in North America. The others are in various places not easily accessible—the Arctic, for example. Some are in bright skies.
Secondly, adding to the fun, I observed the Mars event simultaneously with a friend a thousand miles away from me in Massachusetts. As we exchanged photos and text with our phones, it became quite apparent that latitude made a BIG difference in what we were seeing. Mars slipped behind the Moon 20 minutes earlier here than there. It emerged almost 40 minutes later up north than down south. Imagine having a collection of friends observing the same event but having time or visual observations differ because of the location. That does not happen with all astronomical events, for example, Lunar Eclipses; when you observe for the start or end of totality or shadow crossings of specific craters, it happens at the same moment everywhere. The occultations don’t.
What other 'astronomical bucket lists’ besides solar system selfies, planetary occultations and constellation ‘collecting’ can you think of? How about a photo or drawing from a telescope view of one of every kind of celestial object—spiral galaxy, open star cluster, binary and triple stars, etc. Leave a comment to this newsletter issue, or a suggestion in Notes to my posting there.
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.
January 20 The Moon occults the bright blue star Spica around 11 PM Central Time. Otherwise you can find Spica only a tenth of a degree (1/5th Moon diameter) away from the nearly Last Quarter Moon. The Moon is also at its smallest apparent size because it is at its Apogee, its farthest orbital point.
January 21 Last Quarter Moon.
January 24 In the dawn find the red giant summer star Antares not quite as close as Spica was, 0.3-degrees. In Australia and New Zealand it is 0-degrees close, i.e. behind the Moon.
January 29 The first New Moon of 2025.
January 31-February 1 Saturn is 1.1-degrees South of the Moon, and occulted by the Moon if you are in SE Asia, China, Japan and Pacific Russia. Closest approach occurs at 11 PM Central Time on the 31st so most North Americans will see this in January, Europeans in February. Venus nearby will be passed by the Moon a few hours later on the 1st.
Observing---Plan-et
==New Naked Eye Comet Briefly Visible==
Mercury still almost has the dawn to itself, with only reddish Mars up on the opposite western side of the sky. But after the 20th, Mercury begins to exit stage left. It rises 40 minutes before sunrise on that date but increasingly shorter times — with its lack of visibility increasing, too—until it gets too deep in the solar twilight and then reaches solar conjunction right after month-end.
Venus reached its maximum distance from the Sun, and rides (finally!) high over the western horizon at almost the same distance through month end, after which it will first slowly then rapidly dive into solar conjunction in the coming weeks. Venus, we hardly saw ye.
It sets after 9 PM local time even as the Sun begins to stay up later than in December. It has a nice 2-degrees-apart conjunction with Saturn on the 19th-20th.
Mars is in its glory, a red-orange world at its largest apparent diameter for the year. It is visible all night from now until early February. Take out those Christmas telescopes and observe its dark surface features and a white polar cap.
Jupiter is visible all evening but sets between 3:30 and 4:30 AM local time.
Saturn sets two hours after evening twilight ends at the start of this period, and only an hour after that at month end. Catch it now before it vanishes into the twilight glow. As stated in the last issue, the thin rings you see in your telescope are getting thinner….because of perspective. As we will have our Equinox in March, when the Sun goes from South of our Equator to North, so does Saturn, relative to Earthly views. In March the rings go edgewise to Earth and we will no longer see the Northern side of the Rings of Saturn—for the next 14 years.
An unexpected comet, with a name similar to a naked eye comet last Autumn, ATLAS C/2024 G3, is making an appearance bright to the naked eye but albeit briefly for Northern Hemisphere observers. A much better show for TGT’s Southern Hemisphere readers. For Northern Hemisphereans, the comet that passed perihelion on the 13th only briefly gets away from the Sun in our sky, setting at most 30 minutes after sunset, thus requiring at least binoculars. If you try with binoculars or a telescope, please absolutely wait until the Sun has completely dropped below the horizon, to protect your eyes! Retina burns are permanent.
As the above map indicates the comet only barely stays north of the Sun before it dives straight south out of view for Northerners. While there are reports of daylight observations of the comet with the naked eye and a roof blocking off the Sun, and some photographs in the low twilight, yours truly has not been able to find it.
The above, made with Stellarium on the Web, shows the comet’s best position for Northerners and this is from Alabama! It will be harder the more North you get. It is highest above the just-set Sun (this is an unrealistic view 30 minutes after sunset, there will be no stars in the sky to see in reality!). But if you noted where on the horizon your Sun set, look only about 5 degrees up around 5PM with binocs (no Sun up!). It may well be naked eye in brightness but very buried in twilight glow. Southern Hemisphere readers, TGT would LOVE some photos! You may find it in your morning skies the next week. By the 20th it will be gone from evening view up North.
This Just In
Meteor Striking Patio Recorded on Security Camera
A very lucky Canadian left his patio two minutes too early to become the next Ann Hodges, a person hit by a meteor. Instead his security camera recorded the impact, the sound of it (sharp and loud, like a bullet hit) and in reviewing the video the actual meteor can be seen falling rapidly to Earth in a few frames before the hit.
Spotted this story in the New York Times front page on the 16th, but this YouTube link is from a Canadian weather channel.
Can you imagine what panic would have been created if some people were sitting on the patio, and ducking for cover??
Looking for Earth-like Planets—Are We Actually Not Alone? (Part 1)
Yours truly was attending virtually the American Astronomical Society winter meeting. Two interesting plenary sessions at the Winter AAS meeting at first glance have nothing really to do with each other. Yet they do. They highlight the multiple methods we are using to look for Earth-like planets around other stars, and the probabilities they exist. Do they? Are they inhabitable? How do we know?
For Context…
The Earth is a terrestrial world orbiting close to a spectral type G star. We have water on the surface (and elsewhere) and oxygen in the atmosphere. Other terrestrials in the solar system have the same Sun but obviously not the same constituents. Did they ever?
Oh, and things change. The Earth didn’t always have O2 in the atmosphere or even a nitrogen atmosphere. And both technology and biology take part in those changes, and leave their fingerprints behind for the changing. There’s been no success whatsoever in finding technology biosignatures—calling Earth!—but in our solar system there are biosignatures, or lack of them, that tell the story that one out of four planets here are terrestrial and have lifeforms.
One more thing. At all star temperatures there is a distance from the star, with a maximum and a minimum distance, where the temperature of the planet will be just right for liquid water. These make the so-called Habitable Zone, or the Goldilocks Zone, where things are not too hot or too cold but just right for water and life. For hotter stars, such as spectral types O, B, A and maybe F (from hottest blue and white stars to just warmer than the Sun in a lighter yellow), the star zone is much much farther away. For cooler stars, types K and M, the stars are redder and the Zone is very close to the star. Additionally, the first types of stars use up their fuel much faster leaving little time for life to develop and evolve to human level. For the latter type of star, the star is miserly with its fuel and lasts a long time, but may not get to the point of developing viable life because of the nearness and color of the star.
The logical place to search would be stars like the Sun, plus or minus. F, G and K type stars. We do search for exoplanets there, but there are some issues. Some folks are searching amongst the M stars, particularly the long-lasting M dwarf stars, smaller than the Sun, not anywhere near the M giant types of stars like Antares or Aldebaran. These are regular stars that have expanded and cooled, are brighter and huge at the near-end stages of their lives. M dwarf stars never get to grow up into giants, and last billions of years longer.
In simple terms, finding exoworlds involves mostly looking for changes in the stars brightness from the planet blocking out small portions of the surface of the star while passing in front of the star. A mini-eclipse, with very tiny light changes, but periodically. This is called a transit. A smaller subset of exoworlds happen because we detect changes in the bright stars’ speeds towards and away from us, very small but also periodic. We rarely have detected exoworlds by actually seeing them in orbit around the star. The reflected starlight off the world is millions of times dimmer than the star, and the planet is vastly smaller, so it is currently just too difficult a method.
The search for life is a more complicated. Among other things, you have to detect an atmosphere during these transits. Then, simplistically, life like us will make changes from the way the planet first was constituted. We want to look for those changes.
The two plenaries covered the searches among M dwarf stars and future searches among more solar type stars. The results are thought-provoking. Here’s a report on the first one.
Mmmmmm Stars….
David Charbonneau of Harvard reported on a search for terrestrial worlds around Low Mass Stars, i.e M dwarfs. The very first question to ask was could the James Webb Space Telescope and the very large telescopes built or being built detect Oxygen, Carbon Dioxide, Methane and water in the atmosphere of a transiting exoplanet? These are the molecules involved in biosignatures.
In our solar system, only one out of four terrestrial worlds are habitable. Whether two others once were is yet to be determined. They also are the four closest planets to the Sun and are small, rocky iron in a mantle of silicates. Is this the standard for all exoplanetary systems?
Charbonneau’s search has limits. The farther away the star, the fainter it and the planet will be. The dimmer the planet, the harder it will be to see the planet’s spectrum, and the closer the star and planet will be in a telescope. Furthermore, the stars had to be no more than 30% of the Sun’s radius. If larger then the spectroscopes can’t detect the lines of the molecules properly. His search among M dwafs, cooler than our Sun, was within a sphere of 15 parsecs around us (essentially a 50 light year radius for a bubble of space). The research group identified 413 M dwarf stars in the bubble.
The goals were to measure the rate of occurrence of transiting exoplanets around these types of stars, measure the rate of gas giants, as opposed to terrestrials, and characterize the magnetic activities of the stars and for how long they are active. The last causes various environmental conditions on the exoworlds, not all positive for life.
The schematic above represents three possible distributions of terrestrials and gas giants in any star system. The red one is our solar system, where the Earth-sized ones numerically are in the max and smaller ones in smaller numbers. Or would the norm be the blue line where gas giants dominate the system? The green line is the idea that there are many very small worlds and fewer and fewer ones as the size of the planets get larger.
So far, the search has determined that one Earth-sized (1-1.5Rearth) exists for every other M dwarf, about 50% of all M dwarfs is the inference. And every fourth M star would have an Earth sized world in the habitable zone.
They also found 7 such worlds. Statistically the distribution in radius is peaked at one Earth-radius. Like us.
What about the Jovian-sized worlds? It is believed that at least here Jupiter especially ‘sculpted’ the distribution of matter, and resulting planets and Jupiter et all weren’t always where they are today. (See figure below.) Jupiter started at just bit over half its current distance and much of the inner solar system was all small matter. Jupiter and Saturn rapidly migrated inwards, disrupting the inner material and the more numerous than today small worlds, then all four gas giants migrated outwards and allowed the inner material to coalesce into the four terrestrials, a leftover debris field of minor planets and not much left of the outer debris. We would have started out like the green line, but the mass distribution overall resembles the blue line today.
But another finding was that low-mass M dwarfs lack many Jupiters at all! In fact, less than 1.5% of them have Jovians. M dwarf systems are more like the red line as we are today than blue or green lines hypotheses on the first graph.
This means that M dwarf planets may not have been as diversified, and modeled like our solar system. Or as likely a site for habitable worlds.
The Habitable World Observatory
The Habitable World Observatory, not set to launch for at least another decade, will look among F, G and K stars for not only habitable worlds, but inhabited worlds. We’ll report on those plans in the next issue of The Galactic Times!
A Patreon account has been set up for The Galactic Times. Right now, the one tier is simply a $2.50 monthly support for your kindness, since The Galactic Times is an otherwise free newsletter now. But we can use the help. There are plans afoot for some additional benefits —outreach info, education resources—to be set up there for paid members, resource materials that can’t be housed on Substack. Yours truly plans to move a lot of The Classroom Astronomer newsletter articles over to the Patreon site, for paid Patrons; that Newsletter will then be shut down and taken off Substack.
To support TGT, please head over to our Patreon for The Galactic Times site.‘