“Shooting stars” from the tau Herculids meteor shower may be visible late this month, but you might want to listen for them instead.
Excitement among meteor enthusiasts is building as we get closer to the much-anticipated meteor outburst that might be produced by a concentrated trail of dusty debris from the nucleus of comet Schwassmann-Wachmann 3 (SW 3) late Monday night into early Tuesday morning (May 30 to 31).
Even if you can’t get a good view of the show because of clouds or light pollution, you can “observe” the meteor shower a different way: by listening to it on the radio!
Under certain conditions, meteors can reflect radio waves in the same way the ionosphere propagates transmissions between widely separated ham-radio operators. The ionosphere usually reflects frequencies below 30 megahertz (MHz), but it’s transparent to higher frequencies, such as the FM broadcast band (88 to 108 MHz).
Such high-frequency (short-wavelength) radio signals generally pass unimpeded through the atmosphere in straight lines; they cannot follow the curvature of the Earth to reach a listener beyond the horizon. Yet when certain layers of the upper atmosphere become ionized, they can reflect the signals back to the ground far away. The lowest such layer, 60 to 70 miles (96 to 112 kilometers) up, is called the E layer of the ionosphere, and that’s the altitude where most meteors are seen.
So, as a meteoroid vaporizes as it passes through Earth’s atmosphere, it briefly ionizes air molecules along its path. Forming an expanding column or cylinder several miles or more in length, these ions can scatter and reflect radio waves, in much the same way a high-altitude jet reflects sunlight and leaves a glowing contrail against the darkening sky after sunset. But because the ion trails disperse rapidly, the reflected radio waves generally last only a few seconds.
Tiny particles tend to vaporize at the bottom of the E layer. Large particles, in contrast, begin to flame higher up. And predictions for the particles shed from comet SW 3 suggest that a majority of these will be large. Such meteors produce longer-lasting ionization, and because they start to “flame on” higher up, they can reflect signals from more distant transmitters.
On the ground, the meteor’s presence is signaled by the momentary enhancement of FM reception from a distant station.
How to listen for meteors on the radio
For this radio method to work, find a frequency where no nearby FM station is broadcasting. You will have a better chance of success by scanning the low-frequency end of the FM band, below 91.1 MHz. Why there? Because that’s where the lower-power stations, chiefly run by colleges, are found, and they’re usually free from local interference from the high-power commercial stations. In fact, unless you live in a very unpopulated region of the country, your chances of finding an open frequency free of interference above 91.1 MHz is rather small, so you’ll need to tune to a distant station on a clear frequency below 91.1 MHz.
FM Atlas, published from 1970 to 2010, provided listings of all FM stations in North America, with the unique feature of frequency-by-frequency maps. Bruce Elving, publisher of the FM Atlas, was a longtime proponent and expert in all things FM. He died in 2011, but as a tribute to his love and dedication to FM radio, the 21st and final edition of FM Atlas (2010) is available for free, courtesy of AmericanRadioHistory.com. You can also see a complete listing of AM and FM stations in the 2010-2011 edition of the M Street Directory.
What do meteors sound like?
Normally, when you’re tuned in to an “empty” radio frequency, you just hear a hissing noise. But as meteors zip through the atmosphere, a distant or silent station will abruptly “boom in” for anywhere from a fraction of a second to several seconds. You might also hear what initially sounds like a “pop” or a whistle, and then as the ionization trail dissipates, the station will quickly fade away. Because of their height, meteors best reflect signals from stations 800 to 1,300 miles (1,300 to 2,100 km) from you.
When should you listen for meteors?
The best time to listen is when the radiant is 45 degrees above the horizon as seen from a point midway between you and the transmitter. At the predicted peak time for Tuesday morning’s potential meteor outburst, parts of Maine and the Canadian provinces of New Brunswick, Nova Scotia and Prince Edward Island will have the radiant close to that preferred altitude, while eastern New York, New England and southern Quebec will not be far behind, at about 50 to 55 degrees.
Also, it is best to tune to a station located in a direction perpendicular to the radiant. Because the SW 3 radiant will be near the brilliant orange star Arcturus in the constellation Boötes, which will be toward the western part of the sky, the better listening directions will be to the north and south of you.
Most meteors are heard but not seen
If you are watching for meteors while monitoring your radio, most of the time, you will hear a “ping” of reception, but you won’t see a corresponding meteor streak in the sky. Recall that most of the meteors you hear are roughly halfway between you and the radio station — about 400 to 650 miles (650 to 1,050 km) away. So they are occurring either near the horizon or just below it. Back in the 1970s, members of the Nippon Meteor Society in Japan who made extensive records of radio meteors noted that only 20% to 40% of meteors heard on the radio were simultaneously observed visually.
What if you can’t find a clear frequency?
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Particularly in large metropolitan areas, finding a clear or empty FM frequency may be all but impossible, even below 91.1 MHz. In many ways, finding a clear frequency seems to go hand in hand with trying to find a dark sky free of light pollution. You’ll probably have a much better chance in rural or country locations.
But if you can’t find a clear FM frequency, don’t despair. You can still listen for meteors on livemeteors.com. A Yagi antenna in the Washington, D.C., metro area constantly detects 55- or 61-MHz analog TV signals in Ontario reflected off of meteor trails. When a meteor passes over — ping! — there is an echo. It’s the next best thing to having free access to a giant government radar!
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
