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May's possible meteor storm offers chance to listen to 'shooting stars' on the radio – Space.com

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“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!

Related: Meteor shower guide 2022: Dates and viewing advice

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? 

Related stories:

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! 

Good luck, and good listening!

Joe Rao serves as an instructor and guest lecturer at New York’s Hayden Planetarium (opens in new tab). He writes about astronomy for Natural History magazine (opens in new tab), the Farmers’ Almanac (opens in new tab) and other publications. Follow us on Twitter @Spacedotcom (opens in new tab) and on Facebook (opens in new tab)

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See A Jaw-Dropping Crescent Moon, 50 Meteors And Hour And Our Billion-Star Milky Way: What You Can See In The Night Sky This Week – Forbes

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Each Monday I pick out the northern hemisphere’s celestial highlights (mid-northern latitudes) for the week ahead, but be sure to check my main feed for more in-depth articles on stargazing, astronomy, eclipses and more.

What To See In The Night Sky This Week: June 27-July 3, 2022

It’s not easy going stargazing in summer at this time of year in the northern hemisphere. The nights are just so short. The best reason to stay up late and go somewhere dark is the sight of the spiral arms of our Milky Way galaxy arcing across the night sky. Look to the southeast and south for that this month—and this week in particular, which will be largely moonless.

When our satellite does emerge from its New Moon conjunction with the Sun expect lush views of a slender crescent Moon. Who said summer was no good for stargazing?

Monday, June 27, 2022: Boötids meteor shower and a crescent Moon meets Mercury

The June Boötids meteor shower—occasionally called the June Draconids or Boötid-Draconids meteor shower—runs annually between June 22 and July 2, but peaks in the early hours of June 27, 2020.

If you are out stargazing late tonight keep an eye out for the 50 or so “shooting stars” per hour expected. The shower’s radiant point—the apparent source of the shooting stars—is the constellation of Boötes.

If you’re still up before dawn you might just catch the planet Mercury just 3.9º from an incredibly slender 2.6% crescent Moon, but be very careful if you use binoculars to help you because the rising Sun is NOT something you want in your field of view.

Tuesday, June 30, 2022: A super-slim crescent Moon and ‘Asteroid Day’

Today is Asteroid Day. With any luck there won’t be anything to see hurtling towards (or even smashing into) our planet, but it’s a good chance to consider the threat posed to Earth of incoming space rocks. What’s really going to change everything is the Vera Rubin Observatory, which from 2022 will deploy a wide-angle camera to map the night sky in real-time—and identify many thousands of hitherto unfound asteroids.

Friday, July 1, 2022: ‘Earthshine’ on a crescent Moon

You should get a much clearer view of a crescent Moon today. Now 8% illuminated, in a clear sky it will be a stunning sight, not least because you’ll be able to see sunlight being reflected onto the Moon by the Earth as “Earthshine” or “planet-shine.” It’s a subtle sight, but once seen cannot be unseen; look at the Moon’s darkened limb with your eyes, or better still, with a pair of binoculars, to appreciate this fine sight.

As a bonus it will be just 3.5° from the Beehive Cluster, though you’ll need a pair of binoculars to see its 30 or so easily visible stars.

Saturday, July 2, 2022: ‘Earthshine’ on a crescent Moon and Regulus

Tonight just after sunset look west for a 14% crescent Moon, once again displaying Earthshine. The stars around it will be those of the “sickle” in the constellation of Leo. The brightest, about 5º left of the Moon, will be Leo’s brightest star, Regulus. It’s one of the brightest stars in the night sky and about 78 light-years distant.

Object of the week: noctilucent clouds

This time of year the twilight seems to last forever at northerly latitudes so consider looking for a “ghostly” display of noctilucent or “night shining” clouds (NLCs). At their best in northern twilight skies during June and July (at latitudes between 50° and 70° north and south of the equator), NLCs are very delicate high altitude clouds of icy dust that form about 50 miles/80 kilometres up. Because the Sun is never too far below the horizon at these latitudes they get subtly lit up for a short time. They’re best seen with the naked eye or a pair of binoculars.

Wishing you clear skies and wide eyes.

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Astronomers Found a Crater From The Mystery Rocket That Smashed Into The Moon – ScienceAlert

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The Lunar Reconnaissance Orbiter (LRO) – NASA’s eye-in-the-sky in orbit around the Moon – has found the crash site of the mystery rocket booster that slammed into the far side of the Moon back on 4 March 2022.

The LRO images, taken May 25th, revealed not just a single crater, but a double crater formed by the rocket’s impact, posing a new mystery for astronomers to unravel.

Why a double crater? While somewhat unusual – none of the Apollo S-IVBs that hit the Moon created double craters – they’re not impossible to create, especially if an object hits at a low angle. But that doesn’t seem to be the case here.

Astronomer Bill Gray, who first discovered the object and predicted its lunar demise back in January, explains that the booster “came in at about 15 degrees from vertical. So that’s not the explanation for this one.”

The impact site consists of an 18-meter-wide eastern crater superimposed on a 16-meter-wide western crater. Mark Robinson, Principal Investigator of the LRO Camera team, proposes that this double crater formation might result from an object with distinct, large masses at each end.

Before (2022-02-28) and after image (2022-05-21) of the Moon. (NASA/GSFC/Arizona State University)

“Typically a spent rocket has mass concentrated at the motor end; the rest of the rocket stage mainly consists of an empty fuel tank. Since the origin of the rocket body remains uncertain, the double nature of the crater may help to indicate its identity,” he said.

So what is it?

It’s a long story. The unidentified rocket first came to astronomers’ attention earlier this year when it was identified as a SpaceX upper stage, which had launched NASA’s Deep Space Climate Observatory (DSCOVR) to the Sun-Earth L1 Lagrange Point in 2015.

Gray, who designs software that tracks space debris, was alerted to the object when his software pinged an error. He told The Washington Post on January 26 that “my software complained because it couldn’t project the orbit past March 4, and it couldn’t do it because the rocket had hit the Moon.”

Gray spread the word, and the story made the rounds in late January – but a few weeks later, he received an email from Jon Giorgini at the Jet Propulsion Lab (JPL).

Giorgini pointed out that DSCOVR’s trajectory shouldn’t have taken the booster anywhere near the Moon. In an effort to reconcile the conflicting trajectories, Gray began to dig back into his data, where he discovered that he had misidentified the DSCOVR booster way back in 2015.

SpaceX wasn’t the culprit after all. But there was definitely still an object hurtling towards the Moon. So what was it?

A bit of detective work led Gray to determine it was actually the upper stage of China’s Chang’e 5-T1 mission, a 2014 technology demonstration mission that lay the groundwork for Chang’e 5, which successfully returned a lunar sample to Earth in 2020 (incidentally, China recently announced it would follow up this sample return mission with a more ambitious Mars sample return project later this decade). 

Jonathan McDowell offered some corroborating evidence that seemed to bolster this new theory for the object’s identity.

The mystery was solved.

Except, days later, China’s Foreign Minister claimed it was not their booster: it had deorbited and crashed into the ocean shortly after launch.

As it stands now, Gray remains convinced it was the Change 5-T1 booster that hit the Moon, proposing that the Foreign Minister made an honest mistake, confusing Chang’e 5-T1 with the similarly named Chang’e 5 (whose booster did indeed sink into the ocean).

As for the new double crater on the Moon, the fact that the LRO team was able to find the impact site so quickly is an impressive feat in itself. It was discovered mere months after impact, with a little help from Gray and JPL, who each independently narrowed the search area down to a few dozen kilometers.

For comparison, The Apollo 16 S-IVB impact site took more than six years of careful searching to find.

Bill Gray’s account of the booster identification saga is here, as well as his take on the double crater impact. The LRO images can be found here.

This article was originally published by Universe Today. Read the original article.

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New Zealand Says It's Set to 'Star' in NASA's Return to the Moon – BNN

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(Bloomberg) — New Zealand is trumpeting its role in a plan to return humans to the Moon, saying it is set to star in NASA’s Capstone mission that will test the orbit for a lunar space station.

Rocket Lab has announced it will launch a satellite from Mahia, New Zealand, to test the lunar orbit for Gateway, a planned Moon-orbiting outpost that will provide astronauts with access to the lunar surface. Separately, New Zealand’s government said Monday it has signed an agreement with NASA to conduct new research to track spacecraft approaching and orbiting the Moon.

“The New Zealand space sector is set to star in NASA’s Capstone Moon mission,” said Andrew Johnson, manager of the New Zealand Space Agency. Launching into lunar orbit from New Zealand is “a significant milestone,” while the new research “will be increasingly important as more countries and private actors send spacecraft to the Moon,” he said.

NASA’s Artemis Program plans to return humans to the lunar surface as early as 2025, renewing human exploration of the Moon and progressing toward the exploration of Mars. It plans to land the first woman and first person of color on the Moon and explore more of the lunar surface than ever before.

Rocket Lab said it could launch the CubeSat satellite as soon as Tuesday, with the launch window open through July 27.  

New Zealand’s agreement with NASA will see a University of Canterbury-led research team, which includes contributors from the University of Auckland and the University of New South Wales in Australia, attempt to track spacecraft from observatories in Tekapo and Canberra. 

The scientists intend to validate their observations and algorithms to predict spacecraft trajectories enroute to the Moon and within their lunar orbits against NASA’s Capstone mission data.

©2022 Bloomberg L.P.

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