Close encounters #3: Asteroiden scheren langs de aarde

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Asteroid to pass between Earth and moon in 17,500mph close encounter
The chunk of space rock measuring up to 300ft will buzz the planet at a distance of around 100,000 miles, giving astronomers the chance to study it in detail.

An asteroid big enough to wipe out a city will hurtle between Earth and the moon's orbit this weekend in a close encounter visible through binoculars and small telescopes.

The chunk of space rock measuring up to 300ft (90m), around the size of Westminster's Elizabeth Tower (316ft or 96m) which houses Big Ben, will fly by at about 17,500mph.

Passing at around 100,000 miles (168,000km) - less than half the distance between Earth and the moon - will give astronomers the chance to study the "city killer" asteroid at close quarters.

While such cosmic encounters are common, NASA said it's rare for one so large to come so close - about once a decade.

Discovered a month ago, the asteroid known as 2023 DZ2 will harmlessly buzz the planet on Saturday, before heading back off into the solar system.

European Space Agency's planetary defence chief Richard Moissl said: "There is no chance of this 'city killer' striking Earth, but its close approach offers a great opportunity for observations."

Scientists with the International Asteroid Warning Network view it as good practice for planetary defence if and when a dangerous asteroid does pose a threat, according to NASA.

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Grote asteroide scheert zaterdag vlak langs de aarde

Haal zaterdag je telescoop of verrekijker maar tevoorschijn, want aan de hemel is een opmerkelijk verschijnsel te zien. Een asteroïde die groot genoeg is om in één klap een stad uit te roeien, vliegt dan tussen de aarde en de maan door. Dat gebeurt gemiddeld maar een keer per tien jaar, zegt NASA.

Ontdek 'm nu
Vooropgesteld: geen zorgen. De asteroïde blijft op veilige afstand en zal de maan en de aarde niet raken, schrijft de Britse krant The Guardian. "Er is geen kans dat deze 'stadsmoordenaar' de aarde treft", zegt Richard Moissl, hoofd planetaire defensie van het Europees Ruimteagentschap.

Maar het is wél een mooie kans voor wetenschappers om de ruimterots van dichtbij te bestuderen. "De nabijheid ervan biedt een geweldige mogelijkheid voor observaties." Astronomen van het International Asteroid Warning Network zien de langsvliegende asteroïde als een goede oefening in het beschermen van de aarde, voor het geval er ooit een gevaarlijke asteroïde wordt ontdekt die de aarde wél zou kunnen raken, zegt de NASA.

Dat asteroïden langs vliegen is niet zo opmerkelijk. Maar volgens NASA is het zeldzaam dat zo'n grote asteroïde - wetenschappers schatten dat de diameter tussen de 49 en 90 meter is - van zo dichtbij te zien is.

De ruimterots, genaamd 2023 DZ2, vliegt eerst langs de maan, om een paar uur later langs de aarde te komen met een snelheid van 28.000 kilometer per uur. De asteroïde vliegt dan op iets meer dan 68.000 kilometer afstand langs. De laatste keer dat de 2023 DZ2 de aarde passeerde was in 2004, volgens het Near-Earth Object Coordination Centre.

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Op maandag 27 maart 2023 00:08 schreef Kriegel het volgende:
Wacht even, dus niet alleen is hij een paar dagen van tevoren pas opgemerkt (fijn idee ), maar in 2004 is dit ding gewoon voorbij komen vliegen zonder dat iemand 'm gezien heeft? :|

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Very bright fireball, sonic boom over Auckland, New Zealand

A bright fireball followed by a sonic boom was seen over North Island, New Zealand at 10:42 UTC (22:42 LT) on June 3, 2023.

The International Meteor Organization (IMO) received 19 reports from Auckland, Northland and Waikato, and 2 videos.

Professor James Scott from Otago University’s Department of Geology said he had received quite a few reports of meteor sightings.

“It was seen across the top of the North Island, and captured on a security camera and also one of the fireball cameras,” Scott told NZ Herald.

“There was also a sonic boom heard by several people. There will almost certainly be more security cameras that picked it up but that often takes a few days to show up.”

One of the witnesses described the event as a huge white ball flash heading north across the sky.

Others said it was a ‘massive meteorite’… a beautiful sighting that lasted 10 to 30 seconds, with very bright white light, brighter than the moon followed by a long yellow tail and a small explosion before disappearing.

AMS event #2882-2023 caught from Whangrei Heads NZ

AMS event #2882-2023 caught from Auckland NZ

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Extremely close approach of asteroid 2023 RS at just 0.03 LD – the 5th closest on record

A newly-discovered asteroid designated 2023 RS flew past our planet at an extremely close distance of just 0.027 LD or 0.00007 AU (~10 361 km / 6 438 miles) from the center of Earth at 14:26 UTC on September 7, 2023. This is the 53rd known asteroid to fly past Earth within 1 lunar distance since the start of the year and the first so far this month.

The asteroid’s nearest point was around 2 381 km (1 479 miles) from the surface, ranking 2023 RS as the fifth closest asteroid flyby ever recorded.

The year 2023 also witnessed the fourth closest encounter with asteroid 2023 BU at 0.00007 AU on January 27. The third closest was in 2021 with 2021 UA1 at 0.00007 AU, followed by the second closest in 2020 with 2020 QG at 0.00006 AU. The closest known flyby occurred at 17:21 UTC on November 13, 2020, with asteroid 2020 VT4 approaching within 0.00005 AU (0.018 LD/6 746 km/4 191 miles) of Earth’s center.

2023 RS (temporary ID C9FMVU2) was first observed at Mt. Lemmon Survey just a couple of hours before its close approach. The object belongs to the Apollo group of asteroids and has an estimated diameter between 0.93 and 2.1 m (3 – 6.9 feet). It flew past us at a speed of 13.6 km/s.

Its next close approach will take place on January 29, 2024, at a distance of about 0.45 AU.

f asteroids measuring 0.93 m (3 feet) and 2.1 m (6.9 feet) in width were to enter Earth’s atmosphere, they would largely burn up due to intense friction with the air, creating bright streaks in the sky. The 0.93-m asteroid, being smaller, would likely disintegrate entirely before reaching the Earth’s surface. The 2.1-m asteroid, while also small, might have fragments that survive the atmospheric burn-up and reach the surface as meteorites. However, the impact of such fragments would be localized and unlikely to cause significant damage or harm. The primary effects of these asteroids would be the spectacular visual displays they’d offer, particularly during nighttime entries.

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Very bright fireball over downtown Beijing, China

A very bright fireball was observed in the skies over downtown Beijing, China at 11:40 UTC (19:40 local time) on Monday, January 29, 2024, creating a spectacular sight for residents and visitors.

This astronomical phenomenon, characterized by a sudden and intense light, is commonly caused by a meteor entering the Earth’s atmosphere and burning up, resulting in a bright and fast-moving light across the sky.

Fireballs, especially ones as bright as the one witnessed in Beijing today, are a rare occurrence over populated areas and are often followed by sonic booms. Sonic booms occur when the meteor travels through the Earth’s atmosphere at a speed exceeding the speed of sound, creating a powerful shockwave. This can sometimes be heard on the ground as a loud, explosive noise, adding an auditory element to the visual spectacle of the firebal

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Near-Earth asteroids 2024 JR1 and 2024 JD close approach live views

Two near-Earth asteroids, designated 2024 JR1 and 2024 JD, are set to make a close approach to Earth between May 7 and May 8, 2024. Both asteroids will come within less than the distance of the moon (1 LD), with 2024 JR1 approaching at about 0.72 LD (295 000 km / 183 700 miles) and 2024 JD at approximately 0.77 LD (275 800 km / 171 415 miles).

Asteroid 2024 JR1, discovered on May 4, 2024, measures between 7.6 and 17 m (24.9 to 55.8 feet) in diameter. It is expected to reach its closest approach to Earth on May 7 at 00:04 UTC.

The second asteroid, 2024 JD, was discovered slightly earlier, on May 1, 2024. It has an estimated diameter of 8.2 to 18 m (26.9 to 59.1 feet) and will make its nearest approach on May 8 at 13:34 UTC.

Both asteroids were tracked and analyzed by NASA’s Jet Propulsion Laboratory, which confirmed that there are no risks to Earth from these encounters.

The Virtual Telescope Project has announced it will host a live feed of these close approaches, offering a unique opportunity for public viewing. The live stream is scheduled to begin on May 6, 2024, at 19:30 UTC.

The Virtual Telescope Project provides an excellent platform for astronomy enthusiasts and the general public to observe these asteroids from home. Those interested in witnessing this celestial spectacle can access the live stream at the designated start time.

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Asteroid 2024 UG9 flew past Earth at just 0.02 LD – second closest of the year

A newly discovered asteroid designated 2024 UG9 flew past Earth at a distance of 0.021 LD / 0.00006 AU (8 850 km / 5 499 miles) from the center of our planet at 12:42 UTC on October 30, 2024. This places it about 2 479 km (1 540 miles) from Earth’s surface.

This is the 105th known asteroid to fly past Earth within 1 lunar distance (<1 LD) since the start of the year and the 30th so far this month, making October the month with the most <1 LD asteroid flybys since at least 2020.

This is also the closest <1 LD asteroid flyby of the month and the second closest of the year, after 2024 LH1 at 0.00005 on June 6.

2024 UG9 was first observed at Mt. Lemmon Survey, Arizona at 07:02 UTC — 5 hours and 39 minutes before its closest approach to Earth.

The object belongs to the Apollo group of asteroids and has a diameter between 0.82 and 1.8 m (2.7 – 5.9 feet).

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Asteroïde 2024 YR4 kán over acht jaar de aarde raken: ‘Bij inslag in stad zijn de rapen goed gaar’
Een nieuw ontdekte asteroïde koerst met duizelingwekkende snelheid in de richting van onze planeet en kan uiteindelijk de aarde raken. Onderzoekers zeggen dat er een kans van 1,3 procent is dat de ruimtesteen ons treft – maar pas over bijna acht jaar.

Een Nasa-analyse van de grote asteroïde, met de aanduiding 2024 YR4, stelt dat deze een kans van meer dan 1 procent heeft om de aarde te treffen op 22 december 2032. Dat klinkt zorgelijk, maar het betekent ook dat er een kans van ongeveer 99 procent is dat deze asteroïde geen impact heeft.

Momenteel hebben geen andere bekende grote asteroïden een inslagkans van meer dan 1 procent. Mogelijke impactlocaties omvatten op dit moment de oostelijke Stille Oceaan, het noorden van Zuid-Amerika, Afrika en Zuid-Azië, volgens schattingen.

De asteroïde, die naar schatting ongeveer 40 tot 90 meter breed is, zou ‘een ernstige inslag’ veroorzaken, stellen experts. Zo kan de steen met gemak een stad wegvagen of in zee belanden en een tsunami veroorzaken.


Van een zogeheten planet killer (met een impact zoals de ruimterots had waardoor de dinosauriërs werden uitgeroeid) is echter geen sprake. Dat voorwerp was vermoedelijk tussen de 10 en 15 kilometer breed, al is dat onzeker.

Gerapporteerd in Chili
 Asteroïde 2024 YR4 werd voor het eerst gerapporteerd op 27 december 2024 door het door Nasa gefinancierde Asteroid Terrestrial-impact Last Alert System-station in Chili. Deze ruimtesteen trok de aandacht van astronomen toen die op de risicolijst verscheen. Deze lijst omvat alle bekende asteroïden die zich in de buurt van de aarde bevinden en die op de aarde zouden kunnen inslaan in de toekomst.  

Er zijn in het verleden verschillende objecten geweest die op de risicolijst zijn gestegen en uiteindelijk zijn gedaald naarmate er meer gegevens binnenkwamen. Nasa benadrukt dat onderzoekers op basis daarvan in de toekomst kunnen concluderen dat de asteroïde helemaal geen kans meer heeft om de aarde te raken.

Vincent Icke, hoogleraar theoretische sterrenkunde aan de Universiteit Leiden, vindt 1,3 procent kans op impact niet miniem. ,,Als je een op de honderd keer door de bus wordt geraakt, stap je ook niet de weg op.”

Erg versimpeld
Volgens Icke is het beeld van een enorm rotsblok dat op aarde afkoerst wel erg versimpeld. ,,Onze planeet raken (feitelijk zijn we een dubbelplaneet met de maan samen, red.) is niet zo eenvoudig, want een kleine koerswijziging kan al een misser opleveren. Dat laat onverlet dat een impact wel mogelijk is. Hoe groot de schade daarvan zal zijn, hangt af van de grootte en de samenstelling. Dat maakt een wereld van verschil.”

Een asteroïde die inslaat met 20 tot 30 kilometer per seconde, kan veel schade veroorzaken. Hoeveel, is afhankelijk van het materiaal waaruit die bestaat, de inslaghoek, de diepte, de plek en de afstand tot bewoond gebied. ,,Dan zijn in een stad de rapen goed gaar, al is de kans op een voltreffer heel gering.” Bij een tsunami, veroorzaakt door een impact op zee, is het risico veel groter op een breed getroffen gebied, aldus Icke.

,,In alle andere gevallen zal er een behoorlijke inslagkrater of plons plaatsvinden, maar die is niet heel erg verwoestend. Zeker ook omdat enkele maanden van tevoren wel redelijk precies kan worden vastgesteld waar de inslag gaat plaatsvinden. Dan kunnen er maatregelen worden getroffen en hoeven er geen mensenlevens verloren te gaan”, concludeert expert Icke.

Ook de ESA houdt de recent ontdekte asteroïde goed in de gaten, meldt de Europese ruimtevaartorganisatie.

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Earth could face devastation in 2182 if asteroid Bennu collides, scientists warn

WASHINGTON,— Asteroid Bennu, a near-Earth object currently making its closest pass by our planet, poses a potential risk for collision in the distant future, scientists warned.

Bennu, which orbits the Earth every six years, passes as close as 186,000 miles (299,000 km) to the planet. Experts estimate a slim one-in-2,700 chance of Bennu striking Earth in September 2182, according to recent findings.

New computer simulations of a potential impact by Bennu—a 500-meter asteroid—reveal that the consequences would be severe.

If the asteroid were to strike Earth, it would not only cause immediate destruction but also lead to long-lasting disruptions in global climate and ecosystems. Researchers predict that the impact would throw 100-400 million tons of dust into the atmosphere, which could significantly alter climate patterns for up to four years.

“The dust would block sunlight, triggering a dramatic global ‘impact winter’ marked by colder temperatures, less rainfall, and reduced sunlight,” said Lan Dai, a postdoctoral research fellow at the IBS Center for Climate Physics (ICCP) at Pusan National University in South Korea. Dai, who led the study published in Science Advances, explained that the effects of such an impact would be felt worldwide.

According to the research, the worst-case scenario would result in a drop in Earth’s average surface temperature by about 7°F (4°C) and a 15% reduction in rainfall. Additionally, photosynthesis would decrease by 20-30%, and the ozone layer—critical for protecting life on Earth from harmful ultraviolet radiation—could be depleted by as much as 32%.

In the aftermath of the impact, the Earth would experience a combination of earthquakes, powerful shockwaves, wildfires, and thermal radiation. The collision would also create a massive crater and send debris into the atmosphere, further disrupting climate systems, experts said.

The study also highlighted the differing effects on life on land and in the oceans. While plant growth on land would take years to recover, plankton in the ocean would bounce back much faster, showing an unexpected increase due to iron-rich dust falling into the sea.

However, the general decline in plant life, both on land and in the oceans, could lead to long-term disruptions in food supply and ecosystems.

Severe ozone depletion would occur in the stratosphere, the second layer of the atmosphere, due to warming caused by the absorption of dust particles from the impact. This ozone loss would further harm life on Earth, particularly by increasing exposure to harmful ultraviolet radiation.

The study did not focus on estimating the number of human casualties, but Dai said that the location of the asteroid impact would play a significant role in determining the death toll.

A Bennu-sized asteroid strike would likely cause catastrophic loss of life, with climate and environmental disruptions severely affecting the global population.

Scientists have long studied Bennu, which is considered a “rubble pile” asteroid—a loose collection of rocks rather than a solid body.

Bennu is thought to be a remnant of a larger celestial body that formed early in the solar system’s history about 4.5 billion years ago. In 2020, NASA’s OSIRIS-REx spacecraft visited Bennu and collected rock and dust samples for analysis.

Research on these samples revealed that Bennu contains some of the chemical ingredients necessary for life, supporting the theory that asteroids may have played a role in delivering the building blocks for life to early Earth.

Asteroids have caused significant destruction in Earth’s history. One such asteroid, estimated to be 6-9 miles (10-15 km) wide, struck the Yucatán Peninsula in Mexico 66 million years ago, causing the extinction of nearly three-quarters of Earth’s species, including the dinosaurs.

In response to the growing concern about asteroid impacts, NASA conducted a planetary defense test in 2022, using the DART spacecraft to alter the trajectory of an asteroid, Dimorphos. This test is part of ongoing efforts to develop strategies for deflecting any potential asteroid threat.

Although the chances of Bennu striking Earth are low—only about 0.037%—researchers stress that the potential impact could have catastrophic consequences.

“Even though the probability is small, the impact would likely lead to severe food shortages and climate conditions similar to those following some of the largest volcanic eruptions in recent history,” said Axel Timmermann, ICCP director and senior author of the study. “It’s important to consider the risk,” he added.

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Op vrijdag 7 februari 2025 13:25 schreef Pinnenmutske het volgende:
Vredefortkrater staat op mijn bucketlist

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Op vrijdag 7 februari 2025 13:28 schreef Pinnenmutske het volgende:

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Zuid Afrika en mijn interesse