FTV: The Sky is Falling
When the old Marquette Monthly paper ceased publishing some years ago, we lost The Night Sky feature. The Night Sky was the brainchild of Marquette Astronomical Society member Craig Linde of Palmer, MI. With his kind permission, we ran his monthly compilation of astronomical events in both The Ontonagon Herald and Andy Hill’s Wakefield News / Bessemer Pick & Axe for many years. When MM folded, we missed a month or two of The Night Sky before deciding the only way to find a replacement was to do it ourselves. Thus was born the monthly AstroCal feature we began publishing in both papers mentioned above and on our WOAS-FM website www.woas-fm.org. I recently noticed that MM has begun publishing again (although I can not say when they restarted), but found no evidence that Craig had resumed writing The Night Sky. Craig does post regularly on the MAS facebook page as does D. Scott Stobbelaar, the former director of the Shiras Planetarium in Marquette, but we have not found TNS on the MAS site, either. With that said, I would like to expand on the May 2022 AstroCal column where our readers were introduced to the American Meteor Society, or AMS for short (www.amsmeteors.org).
The AMS is a non-profit scientific organization formed in 1911 to “inform, encourage, and support research activities of both amateur and professional astronomers who are directly interested in meteoric astronomy.” A quick scan of the links provided on the menu page at the beginning of their website lead to a host of information about meteors and fireballs. By definition, a ‘fireball’ is a very bright meteor (usually brighter than magnitude -4, which is about the same magnitude as the planet Venus). A fireball will oftentimes leave a visible trail that may last several seconds after the object creating it passes from view. On April 9, 2022, my son and I observed just such a fireball while driving home from the Houghton area. We duly reported our observation to the AMS site under a link labeled ‘Report a Fireball’ (naturally).
We were about five miles outside of Greenland, MI traveling SW on M-26. At first glimpse, I saw a fast moving object in the upper left corner of the windshield. My first thought was, “airplane”. By the time I called attention to it, the object was halfway across our field of view. When it disappeared from our view behind the tree line to our right, it was trailing a bright streak that covered half of the open sky ahead of us. The ‘head’ of the streak seemed to be widening as if the meteor itself was starting to break apart as it disappeared from our view. The path seemed to be about 30 degrees in elevation and mostly parallel to the horizon in front of us. After a few seconds, the bright trail it left behind faded. A quick look at the dashboard clock told us it was 9:40 p.m. EDT. Noting the SW direction we were traveling, my first impression of the meteor’s direction of travel was toward the NW.
As soon as we got home, I looked up the AMS site and clicked on the ‘Report a Fireball’ link. The system they use for reporting observations has been greatly simplified in the last decade so anyone familiar with filling out on-line forms or surveys can easily navigate this site. The form begins by instructing you the kinds of things one should NOT report (events lasting more than 30 seconds (fireballs do not last that long), items that blink, etc). It then asks if you have a photo or video of the event (we did not). When asked for the location the observation was made, I entered ‘M-26, Greenland, MI 49929’. This produced a Google Map with a ‘person’ icon located in the middle of downtown Greenland. I was able to move the icon down M-26 to the approximate location we were driving when we saw the fireball.
The site walks you through specific questions about your observation. Each section provides very clear instructions about the information they are seeking so one does not need a PhD of any kind to provide the answers requested. When the log form information has been entered, the site informs you the observation is now PENDING and will be published in their ‘fireball log’ after it has been verified and compiled.
By the next morning, there had been over thirty observations of this fireball recorded from Iowa, Minnesota, Wisconsin, Illinois, and Michigan (including ours from Greenland). By late afternoon, the number of recorded observations had climbed to more than 300. The map provided (showing little ‘people’ representing all the reporting sites) was so cluttered with icons it was impossible to see the ‘trajectory arrow’ that had been calculated. Filtering out all but six of the locations uncovered the arrow and gave us a bit of a surprise. From our vantage point, we had guessed the meteor may have crossed the western part of Lake Superior. The combined observations showed it first appeared where the southern border of Minnesota meets the western border of Wisconsin (roughly 250 miles as the crow flies from Greenland) and was indeed traveling in a northwesterly direction but well west of Lake Superior. One can visit the AMS site and find the information about this event in their ‘fireball log’. If you click on the ‘person icon’ in the upper right, it will provide the information we reported about the whole event.
The other thing that surprises me each time I visit the AMS site is the volume of observations they collect. It is estimated that some 25 million meteoroids, micrometeoroids, and other space debris enter the Earth’s atmosphere each day. This amounts to about 15,000 tons of material. Many are too small to create an observable streak and those falling during daylight hours or in remote areas are not usually seen. With that said, there are still an amazing number of meteors of significant brightness to result in dozens of reports recorded on the AMS site every day. I have seen a lot of meteors over the years, but the April 9, 2022 fireball was only the third ‘brighter than run of the mill’ meteor observations I have witnessed.
Back in 1981, John Fischer and I were filling in a summer’s worth of band gigs when Mark Bobula found himself short of help with The Easy Money Band. After one wedding reception held on a hot August night, we were lounging in our living room having a post gig brew. From my seat facing east over the Ontonagon Golf Club, I happened to notice a bright ‘star’ about 45 degrees up from the horizon. I asked John, “Is Jupiter visible right now?” and we stepped out onto the back porch to get a better look. By then, the object in question had grown twice its original brightness and appeared to be trailing a growing plume of illuminated matter. By the time it went below our horizon, the flowing plume actually appeared to be a tail of flames. We quickly ruled out a comet (comets have tails but do not move that fast) but could not decide if it was a natural or man-made object we saw burning up in the atmosphere.
A few days later, the newspaper (no internet or AMS website was available yet) reported this phenomenon had been seen from Michigan all the way to the Atlantic coast over New England. It was attributed to the Soviet Union who had recently launched a satellite. What we observed was one stage of the launch vehicle burning up as it re-entered the Earth’s atmosphere. These days, one only needs to do a quick internet search or watch CNN to see video of objects burning up as they enter the atmosphere. Seeing something like this in person is not a common occurance and to this date, it is the only observance of a re-entering man-made object I have witnessed.
The second great fireball I observed took place in the early 2000s. My next door workmate and I would make it a point to catch a pre-school breakfast downtown a couple of times a month. It was nearing 7 a.m. and it appeared he had not seen me pull into his driveway. I knocked on the door and was admiring the first rays of light creeping up from the eastern horizon. Had I been facing the door, I would have missed it entirely. In the still relatively dark sky directly to the south, a bright , blue-green object caught my eye. It was between 40 and 50 degrees above the horizon and moving in a west to east direction. Like the April 2022 fireball, it was bright and forming a long tail that covered about one third of the sky. Just as the trail faded, the door behind me opened and I commented, “Man, you are five seconds late!” as I recounted what I had just seen.
At this hour of the morning, I wasn’t sure how many reports of this fireball would be turned in to the AMS site. As it turned out, there were two other reports; one observer near Milwaukee, WI and another just north of Grand Rapids, MI. I was corresponding then with my cousin Wally down south so I sent him the details. He responded about the siting twice. The first thing he said was, “When I was much younger, I was at camp on the west shore of Lake Gogebic one spring weekend. In the morning, I found a bunch of spots on the lake ice that had been punched by fragments of what I assumed was a meteorite. Each hole had let enough water flow up on the ice that there were numerous round patches of clean ice sitting on top of the old ice. I never thought to go back later and see if I could find any of the fragments.”
Wally was an engineer by trade so he took the data from the three recorded sightings and put his math skills to work. He was able to calculate a trajectory for the fireball I had seen using the elevation and direction data from the AMS observations. He sent me a map with an arrow drawn across the top of Lake Michigan. It started near Green Bay and passed across the top of the lake between the Upper and Lower Peninsulas. It was aimed at the Mackinac Bridge, but it would be hard to tell if it punched any holes in Lake Michigan or Lake Huron. Had it hit the bridge, I am pretty sure that would have made the news. The AMS site now generates these maps automatically from their collected data.
Reports like the ones compiled on the AMS site are often used by meteorite hunters. If a meteor vaporizes, there isn’t anything to search for. When an object makes it to Earth (at which point it is now a meteorite), it is possible to do Wally-like computations and locate its possible landing footprint. Many meteorite hounds will identify a possible impact area and then do some good old boots-on-the-ground detective work interviewing anyone who may have witnessed a meteorite fall in their area.
Living in the Great Lakes region, we are blessed with several factors that make this prime meteorite hunting territory. First, there were the periods when continental glaciers covered the area. Many meteorites survived their impact with these massive ice sheets and were left for us to find once the last ice retreated from our area some ten thousand years ago. When the glaciers melted away, they left the land surface covered in debris, or glacial till. Meteorites landing in areas of deep glacial till also stand a pretty good chance of surviving. The next time you pass through beautiful downtown Nisula, stop at the cemetery next to the former St. Henry’s Lutheran Church. On the west side, there is a large irregular headstone marking the final resting place of Lena Simi. The grave marker was unearthed in a farm field by her husband. Word of this unusual rock led to it being examined by geologists from Michigan Tech University in Houghton. They confirmed the classic tear-drop shape and fusion crust (the smooth, shiny appearance created when the meteor was heated by friction with the air) marked it as a meteorite. Rumor has it Farmer Simi was offered a good deal of cash for his find but told the MTU bunch he would rather keep it. He said he would find something to do with it. I can not confirm the rumored conversation, but having stopped to look at this headstone with my classes on many field trips, it does have all the classic characteristics of a meteor. Depending on how steeply it fell through the atmosphere, the original meteor may have been five to ten times larger than the fragment that survived.
In my school archives, I kept a volume from a formal group of meteor hunters. The stories they shared about their detective work finding and collecting meteorite samples were fascinating. My favorite by far was that of a geology professor from Illinois who spent his summers tracking down meteorites. He found one lodged in the frame of an antique car after noticing a hole in a farmer’s garage roof. He and the farmer investigated and found the hole continued through the roof and back seat of the antique car parked inside. They discovered the fragment had finally been stopped by the car’s frame. The professor got lucky in this instance, but looking for holes in garage roofs was not his normal routine.
The professor would drive around the countryside of the surrounding midwestern states looking for rock piles lining farm fields. Farmers in glaciated areas routinely take the numerous glacially deposited rocks from their fields and pile them where they won’t damage their plows. The professor would knock on the door, identify himself, and ask if it would be okay to look through the farmer’s rock piles. No doubt the farmers did not care how many of these pesky rocks the professor hauled away. Among these rock piles, he would look for rocks with unusually high metal content and/or a fusion crust (mentioned above in reference to the Simi Meteorite). To my knowledge, he never offered to pay for his services ridding the farmers of these pesky rocks. In these midwest states previously covered by continental glaciers, there were farms aplenty to search and no doubt the farmers didn’t much care what he did with his finds (though they may have thought the professor was a bit loopy).
When the professor passed away, his wife donated the entire collection to the University of Illinois college system. The state of Illinois cataloged and appraised the collection before distributing it to the various branches of the university system across the state. In the end, they deemed it to be the most valuable private collection of meteorites to be found anywhere in the world. One rarely finds a hobby as lucrative and challenging as meteor hunting.
The most recent major meteorite find came from a fall over Mississippi on May 4, 2022 at 8:30 a.m. CDT. One piece recovered was about a foot long and weighed some 80-90 pounds, but was way too small to have done much damage or to cause the house rattling retorts reported across the state. The fireball observed was ten times brighter than the full moon and generated a shock wave equivalent of 3 tons of TNT. This was a much smaller event when compared to the impact that took out the dinosaurs. They were done in by a six mile wide rock that struck the Earth near the present day Yucatan Peninsula in Mexico. Could it happen again? Certainly. Are spending enough working on preventative measures to keep it from happening? NASA currently devotes less than 1 percent of its total budget ($150 million out of a $21.5 billion budget) – not even close to what we should be spending! Should you lay awake at night worrying about one of these things crashing through your roof? If the odds were that good, you would be a lottery winner by now. The sky will continue to fall, so you might as well look up and enjoy the view. Just don’t waste your time fretting about it. The odds are still in our favor.
Top Piece Video: Okay, Kohotek was a comet and not a fireball, but give me a break . . . it is astronomical! Journey performs the song in Osaka in 1980 and yes, it was inspired by the comet.