Near-Earth objects and close calls

Two views of the recent fireball in Bulgaria!
July 12, 2023, Wednesday // 08:23

A bright light falling in the sky was noticed by hundreds of people in Sofia, Vidin, Lom, Ikhtiman, Plovdiv and other cities and villages in the country minutes before 10 p.m. last night. Users on social networks also published footage from security cameras showing a ball of bright light, which is supposed to be a meteorite.

"So far we have information that it is a fallen meteorite that has been seen in almost every city in the country. People are reporting a bright light in the sky, turning night into day, which ended with a violent rumble. Where exactly the meteorite fell still we don't know yet," Meteo Balkans reported.

bTV reports that at this stage the Bulgarian Academy of Science (BAS) and the observatory in Rozhen do not confirm the information, there is no official information from the National Institute of Meteorology and Hydrology either. According to information from BNT, teams of the Regional Directorate of the Ministry of Internal Affairs - Vidin, conducted an inspection after reports of a strong explosion, there are no reports of casualties or material damage. According to the Romanian authorities, it was a meteorite that exploded in the air.

"Between 25,000 and 30,000 meteorites fall to earth every year. Their total average weight reaches 10 tons. Between 6 and 12 meteorites per year are the size of a washing machine," commented Nikola Petrov from the observatory in Rozhen.

Footage of the phenomenon was captured and distributed on social networks by Alexander Zahariev.

Scientist about the fallen meteorite: Bolide, explodes in the atmosphere, does not reach the Earth

"The phenomenon we observed last night was the fall of a very bright meteorite called a bolide. These bodies explode in the atmosphere before they touch the Earth", explained on Nova TV, Pencho Markishki, a physicist at the Institute of Astronomy of the BAS.

At 10 p.m. on Tuesday, a loud rumble was heard on the territory of the Vidin region and a bright light was seen falling. The phenomenon was also observed in Sofia, Lom, on the Black Sea. The Romanian authorities reported that it was a meteorite that exploded in the air.

At the end of July, two meteor showers are best observed - the Southern Delta-Aquariids and Alpha-Capricornids. The body itself came from the south-southwest. This is an explosion in the atmosphere, several tens of kilometers from Earth. The chance of debris reaching Earth is not high, the scientist said.

According to him, this phenomenon repeats in a smaller version the Chelyabinsk meteorite explosion of February 2013.

"This is a protective function of our atmosphere. All meteor bodies that enter the earth's atmosphere obliquely are heated until they explode and this explosion occurs at a height of several tens of kilometers. In this way, the atmosphere protects us from such phenomena", Markishki said.

The scientist explained that it is not possible to specify the exact size of the meteorite, which can be from a few centimeters to a meter.

The body entered the Earth's atmosphere at a low speed because it reached the Earth on the orbital path, which is the reason for this slow motion. People have watched it for 3-4 seconds, some even 5 seconds. Most meteorites end up in the Earth's atmosphere and burn up completely, but large pieces of rock, or pieces containing metals, can explode lower and debris can reach Earth. There have been bigger cases, such as the Tunguska meteorite of 1908, whose sound wave traveled around the world several times and caused a very serious explosion, but luckily for us such phenomena are rare, the physicist said.

"Meteor showers are very easy to predict because they occur at the same time of the year. The maximum of the Perseid meteor shower is around August 12-13, but we cannot predict how large bodies will enter the atmosphere, especially when it comes to sporadic meteors like the one we are talking about right now. They are unpredictable. If the body is several meters in size, a large laboratory can detect it. But such cases are rare. When it comes to bodies below 10 meters or 1-2 meters, their movement is impossible to predict", the BAS scientist explained.

The Ministry of the Interior on the fallen meteorite: It is a natural phenomenon, the experts will say

"Regarding the loud rumbling - it is not an accident, but a natural phenomenon, the experts will say. There is no tension on the territory of the Vidin region, everything is calm. Already last night, all available forces of the regional directorate were directed to go around the region - to search for people who were injured. There were no fires or material damage," Senior Commissioner Petar Kotsin, director of the Regional Directorate of the Ministry of Internal Affairs in Vidin, said at a briefing.

According to him, there was a single report from the village of Gomotartsi that a loud rumble was heard near an outbuilding.

"There is also information from colleagues in Romania that it is a natural phenomenon," added Senior Commissioner Petar Kotsin.

Screenshot 2023-07-13 at 04-57-54 American Meteor Society.png


 

Airplane-sized asteroid found 2 days after brush by Earth​


Asteroid hidden by sun’s glare​

On July 15, 2023, the ATLAS (Asteroid Terrestrial-impact Last Alert System) observatory in South Africa discovered an asteroid up to 200 feet (60 m) in size two days after it passed closest to Earth. NASA calls an asteroid of this size airplane-sized. Compare 2023 NT1 to the asteroid that hit Arizona some 50,000 years ago, leaving the large, famous Barringer Crater: That destructive asteroid may have been just a bit smaller, at about 160 feet (50 m) in size. The newly discovered asteroid, named 2023 NT1, passed within only 1/4 the distance to the moon. 2023 NT1 came closest to Earth on July 13, 2023, at 10:12 UTC.

Fortunately for us, it was not a threat to Earth. Why didn’t one of our observatories pick it up sooner? Because the asteroid came at us from the direction of the sun. This is a known weak spot in our defense against space rocks. But the European Space Agency (ESA) has a plan for that.

A plan to detect asteroids by the sun​

ESA has a planned mission called NEOMIR that will detect asteroids coming from the sun’s direction. The NEOMIR mission will orbit between Earth and the sun at the first Lagrange point (L1). It’ll act as an early warning system for asteroids – 65 feet (20 m) and larger – that instruments on Earth’s surface cannot see. The downside is that the launch of NEOMIR is not until 2030.

Another notable asteroid that headed toward Earth from the sun’s direction was the Chelyabinsk meteor. This asteroid broke up in the atmosphere on February 15, 2013, over Russia. Scientists estimate it was 65 feet (20 m) in size. It exploded in the atmosphere and created a shockwave that damaged thousands of buildings, breaking windows and injuring roughly 1,500 people from flying shards of glass. Moreover, it was the largest asteroid to strike Earth in over a century.



 
The driver of a car captured with a camera attached to the windshield the moment a green meteorite illuminates and burns over the night sky of the United States, over the border of the states of Louisiana and Mississippi.

According to the American Meteor Society, several sightings were captured in the state of Louisiana around Lake Charles, Houma, Metairie and New Orleans.

 
By Brett Tingle, published about 10 hours ago Video

Screenshot 2023-07-21 at 09-58-57 Interstellar meteor fragments found Harvard astronomer's cla...png
Avi Loeb is back.

The former chair of the Harvard Astronomy Department recently returned from an expedition to the Pacific Ocean near Papua New Guinea that dragged a magnetic sled across the seafloor in an attempt to find fragments of what Loeb claims is the first-known interstellar meteor, what he refers to as "IM1."

This space rock, measuring roughly 1.6 feet (0.5 meters) in diameter, exploded above the Pacific Ocean on Jan. 8, 2014. By following the path of the meteor with the sled, Loeb hoped to find fragments of the rock, which could then be analyzed to determine if their chemical composition could confirm them as being interstellar in origin.

As it turns out, the expedition turned up dozens of tiny metallic spheres, or spherules, less than a millimeter in diameter. In a July 3 blog post titled "Summary of the Successful Interstellar Expedition," Loeb stated definitively that "we did it." The discovery of these spherules, Loeb wrote, "opens a new frontier in astronomy, where what lay outside the solar system is studied through a microscope rather than a telescope."

While Loeb believes he has found evidence of the first interstellar meteorite, others have their doubts. And the debate is turning ugly.

Related: 'Galileo Project' will search for evidence of extraterrestrial life from the technology it leaves behind

Screenshot 2023-07-21 at 10-03-47 Interstellar meteor fragments found Harvard astronomer's cla...png

To find any possible fragments from the airburst that landed on the seafloor, Loeb's expedition dragged its magnetic sled along the path of the meteor, and did the same in a control region outside of that path. In the July 3 blog post, Loeb claims that the composition of the spherules found inside the path of the meteor "are consistently from the same source, whereas the background spherules from the control region had a different morphology and composition." This, Loeb claims, shows that these tiny spheres trace back to the 2014 fireball that reportedly came from interstellar space.

In both public statements and an interview with Space.com, Loeb suggests that the basis for his expedition, which was funded exclusively by cryptocurrency entrepreneur Charles Hoskinson, was a 2022 memo from the United States Space Command stating that data available to the Department of Defense (DOD) is "sufficiently accurate to indicate an interstellar trajectory" for the 2014 meteorite

Screenshot 2023-07-21 at 10-05-34 Interstellar meteor fragments found Harvard astronomer's cla...png
A 2022 memo published by U.S. Space Command asserting that Department of Defense data indicate an interstellar trajectory for the January 8, 2014 fireball over the Pacific Ocean. (Image credit: U.S. Space Command)

However, some say that making the leap from that memo to the spherules Loeb recovered isn't possible. Phil Metzger, a planetary scientist at the University of Central Florida, wrote in a July 16 Twitter post that "connecting that meteor to a few tiny balls of metal taken from a vast area of ocean floor isn’t a capability of the Space Command."

Echoing that, Matthew Genge, a planetary scientist at Imperial College London who specializes in meteorites, said that connecting the spheres with the 2014 fireball — or any meteorite fragments with any other meteor — is impossible. "Meteorite ablation debris has been found, but not from an instrumentally observed fireball," Genge told Space.com via email. "There never has been a micrometeorite derived from a specific fireball event, and never will be, since it is an impossibility."

Peter Brown, an astronomer at the University of Western Ontario, agreed with Genge. If the meteor did in fact enter Earth's atmosphere at the speeds reported, Brown said, it would have been vaporized into fragments much smaller than the spherules Loeb's expedition discovered.

"There has never been a meteorite recovered from any object that hits the atmosphere moving at more than 28 kilometers a second [62,600 mph]," said Brown, who studies meteors and small solar system bodies such as asteroids. "Any solids that would remain would be essentially aerosol-size." (In a 2022 paper in The Astrophysical Journal, Loeb claimed that IM1 was moving between 52 and 58 km per second, or 116,000 to 130,000 mph.)

Uncertain data

Aside from the difficulties in connecting the fireball event to the spherules found on the ocean floor, there are significant doubts about the accuracy of the data that underpin Loeb's claims to begin with.

For one, all sensors, whether ground-based or in space, have margins of error or uncertainty. For many scientific instruments, these levels of uncertainty are known, allowing scientists to take them into account when analyzing the data they produce.

When it comes to the sensors the DOD used to measure the speed and trajectory of the alleged interstellar meteorite, those uncertainties aren't published publicly due to the fact that the U.S. government does not disclose the capabilities of many of its space-based assets.

However, there are public data sets that incorporate measurements from these sensors that can be compared with those made by other sensing stations, allowing researchers to have a rough estimate of the levels of uncertainty in these U.S. government sensors.

That's according to Brown, the co-author of a recent paper accepted for publication in The Astrophysical Journal that calls into question the data supporting an interstellar origin for the 2014 fireball that Loeb claims is responsible for the spherules he recovered from the ocean floor.

Brown told Space.com that, as a result of the finite sampling rate of U.S. government systems such as those used to measure the velocity of the fireball, speed estimates are "systematically overestimated, particularly at higher speeds."

Brown pointed out that in the light curve recorded by the U.S. government (a graph of luminosity over time), the January 2014 fireball displayed four distinct flares as it entered the lower atmosphere, but there was "no evidence earlier in the record of any sort of luminosity."

"And this is a key point," Brown said. "It's very difficult to get an object that purportedly is moving 45 kilometers a second [100,700 mph] down to 18 kilometers [11 miles] altitude, without producing lots of light higher up. It's in fact almost impossible, unless you have something that's extremely strangely shaped. It would have to be very aerodynamic, very low drag, very high density  —  not iron  —  and then you have to explain why it suddenly detonates into small particles at 18 kilometers altitude."

All of these assumptions would be incredibly difficult to reconcile at once, Brown said  — unless the direction and/or speed measurements reported by the U.S. government have similar error levels that are consistent with the larger data sets produced by the same sensors. In that case, the meteor's speed could be considerably lower than Loeb's estimate. And if that's true, Brown said, "the object becomes bound. It's no longer interstellar."

Loeb, however, told Space.com that Brown's paper and the criticism of his claims within it are likely just academic mudflinging. The composition of the spherules alone, he says, prove that they stem from the fireball.

"And now this paper comes out on the day that I'm back from the expedition and says, 'No, the government is wrong. And by the way, the composition shows this object is not interstellar. Its speed was miscalculated, or not measured well, and it's actually three times slower, and it cannot be made of iron,'" Loeb said.

"Yet I hold in my hand the vials with the spherules from this meteor, because most of them were from the meteor path, and then they show the composition is mostly iron," he added. "So that's, you know, that is the kind of pushback from people that are preferring to have an opinion before looking at or seeking evidence."

Screenshot 2023-07-21 at 10-08-06 Interstellar meteor fragments found Harvard astronomer's cla...png

'Betraying the profession'

Aside from disagreements about the accuracy of data, Loeb's claims have been controversial for other reasons. His expedition has drawn criticism for essentially stealing the fragments by not securing the proper permits from the government of Papua New Guinea. In addition, no women were present on the expedition.

Some astronomers also see Loeb's bold claims as an embarrassment for their field. In a blog post dated July 18, Pennsylvania State University astronomer Jason Wright, director of the Penn State Extraterrestrial Intelligence Center, wrote that Loeb's "shenanigans have lately strongly changed the astronomy community's perceptions of him" and that "Loeb's work is unambiguously counterproductive, alienating the community working on these problems and misinforming the public" about the search for possible extraterrestrial intelligence.

For his part, Loeb finds the criticism odd. "Science is supposed to be just based on evidence, not on opinions that have no substantiation," he said. "So if someone says, 'I'm going out to seek some evidence,' it should be all positive. Why would you have any reservations if you call yourself a scientist? I mean, you can call yourself a scientist and just have your own belief system, but then you're betraying the profession."

Despite all of the criticism, Loeb remains undaunted as he presses forward with analyses of the spherules his expedition recovered.

"Science should not be diminished based on the superficial undertones in social media and academic jealousy. And that's a natural tendency, basically, stepping on any flower that rises above the grass level. A lot of people prefer that."

Avi Loeb's upcoming book from Mariner Books, "Interstellar: The Search for Extraterrestrial Life and Our Future in the Stars," will be available on Aug. 29, 2023.

Osaka, JAPAN
The day before yesterday (2023/07/18-19), another bright meteor was captured.#meteor #fireball #流星 #流れ星 #α7C #ATOMCAM2
Last night (2023/07/18-19), I was able to catch a fireball for the first time in a long time.https://youtube.com/shorts/RWBtF13


A suposed meteor reproted in Plainville, CT, moving from what appears to be from the horizon, but moving upward.

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IMPRESSIVE SPORACULATIVE SPORAGOID OVER #ZAMORA YESTERDAY at 21h58m11s UTC (23h58 CEST). This is how it was captured by Antonio J. Robles @AJ_Robles from more than 450 km away, with evanescent trail after several flares. Observed by @carlavidalprado
already listed

AMS
We received 6 reports about a fireball seen over ID, OR and WA on Thursday, June 29th, 2023 around 08:27 UT.
Screenshot 2023-07-29 at 07-42-32 American Meteor Society.png

:cool2: The concern of the coming day is growing as mass consciousness reaches a new level.

The Pew Research Center published the results of a new public survey on Thursday, the 54th anniversary of the Apollo 11 landing on the Moon. The survey assessed Americans' attitudes toward space exploration and space policy issues.

Similarly to five years ago, the survey found that Americans broadly support the national space agency NASA. Three-quarters of respondents had a favorable opinion of NASA, compared to just 9 percent with an unfavorable opinion.

However, as several previous surveys have found, the public has far different priorities for NASA than are expressed in the space agency's budget. In this new report, based on a large survey of 10,329 US adults, the highest support came for "monitor asteroids, other objects that could hit the Earth" (60 percent) and "monitor key parts of the Earth's climate system" (50 percent). Sending astronauts to the Moon (12 percent) and Mars (11 percent) lagged far behind as top priorities for respondents.

Additionally, support for deep space exploration by humans was especially low among women. Just 9 percent of female respondents listed sending humans to the Moon as a "top priority" for NASA, and 7 percent of women said the same about sending humans to Mars.

nasa-survey-1.jpg
The percentage of men and women who say the following areas should be a 'top priority' for NASA.

These priorities come in stark contrast to the funds NASA actually spends on exploration. In fiscal year 2024, for example, NASA has asked Congress for $210 million to continue the development of the Near-Earth Object Surveyor mission. Planned for a launch in 2028, this planetary defense mission will detect, track, and characterize impact hazards from asteroids and comets. NASA also proposes to spend about $2.5 million on Earth Science missions.

Meanwhile, the space agency has asked for about $8 billion to fund its ongoing Artemis program missions next year, including rockets, spacecraft, and landers, to allow for a human landing on the Moon later this decade. NASA officials say the Artemis program will allow the agency to learn skills and techniques that will eventually allow astronauts to fly to Mars in the 2030s or 2040s

Protect the planet

Despite this disparity, NASA has stepped up its planetary-defense activities. Less than a decade ago, the space agency spent less than $50 million a year on detecting and tracking potentially hazardous asteroids, issuing notices and warnings of possible impacts and taking the lead in coordinating planning and response across US government agencies.

The agency, in concert with the European Space Agency, took a notable step forward in November 2021 with the launch of the Double Asteroid Redirection Test mission, which intercepted a near-Earth asteroid and then impacted a small asteroid in 2022. This demonstrated the capability of NASA to potentially deflect an incoming asteroid if a threatening object is found.

Overall, these survey results reinforce the notion that while public support for NASA is fairly broad, it does not run that deep, particularly for human space exploration. And where NASA spends the majority of its funding is where the public—in surveys, at least—seems to be least interested. So what does this mean for space policy?

For a long time after the Apollo program, NASA and space policy leaders lived in hope of seeing another era of support for a large space-exploration budget. In the 1960s, NASA's budget peaked at about 5 percent of federal spending. Now it is about 0.5 percent. If NASA's budget would just double or triple, space enthusiasts would say, think of all the wondrous things we could accomplish.

But those days are never coming back. The US public likes having NASA and astronauts and seeing cool things happen in space. But by and large, their priorities are much more Earth-bound. As Phil Larson, a key space policy official at the Johns Hopkins Applied Physics Lab, told me a few years ago, "The vast majority of the public thinks that we should have a space program that saves Earth."

To NASA's credit, the space agency finally seems to have acknowledged this. Instead of shooting for the Moon with a much larger budget, it has nurtured a commercial space industry. Through public-private partnerships on lunar landers, spacesuits, and other activities, NASA is beginning to fit its deep-space exploration plans within the current budget it receives from the federal government. It has also prioritized landing the "first woman on the Moon" the next time humans go there. Perhaps that will win broader support for lunar exploration in future surveys.
 
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