Asteroid Day (June 30)

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Asteroid Day (June 30)

1margd
Modificato: Giu 29, 2017, 8:14 am

June 30 is anniversary of 1908 Tunguska asteroid explosion (Siberia). A big one, like that in age of the dinosaurs, would reset Gaia--and apparently we are not in a position to defend ourselves... A smaller one like that which hit North America 12,900 years ago might, however, slow down global warming, albeit in an undesirably abrupt, blunt manner: http://www.sci-news.com/geology/science-younger-dryas-climate-shift-asteroid-com...

Asteroid Day 2017 is June 30
Eleanor Imster | June 29, 2017

Hundreds of events – films, concerts, panels with engineers, scientists and astronauts – about asteroids and how to protect our planet from asteroid impacts.

...NASA will mark Asteroid Day 2017 at noon EDT Friday, June 30, with a program airing on NASA TV on how researchers find, track and characterize NEOs – asteroids and comets that come within the vicinity of Earth’s orbit and could pose an impact hazard to Earth – and how NASA is working to get our nation prepared to respond to a potential impact threat. Watch here.

...The NASA broadcast will be part of a 24-hour Asteroid Day program from Broadcasting Center Europe, beginning at 9 p.m. ETD June 29 (1 a.m. June 30 UTC translate to your time zone) and streaming online here...

http://earthsky.org/space/international-asteroid-day-june-30

2margd
Ago 9, 2017, 8:10 am

Puts our squabbling with other countries in perspective...

How the World Could End: The Perseid Meteor Showers, Doomsday Rocks and Other Signs of Cosmic Catastrophe
By Newsweek Archives On 8/8/17

...Asteroids, chunks of rocks or metal, float mostly between the orbits of Mars and Jupiter. Occasionally, one bumps another toward Earth. This cosmic billiards ensures a constant supply of new asteroids with orbits that might intersect Earth's.

...the Oort Cloud (region beyond Plutoas the solar system's bench is) the place where comets not quite ready for the starting lineup await their big break. It comes in the form of a gravitational kick from a passing cloud of dust and gas. Once sent into the game, the comet speeds toward Earth; as the sun's heat turns its frozen gases to vapor, the comet grows a tail and its surface erupts with "jets" of gas and dust. About 200 comets revisit Earth's environs more often than once every two centuries. They include Swift-Tuttle...and Halley.... But no one knows how many never-before seen comets are heading our way. "For those coming in from the far reaches of the solar system for the first time, we have virtually no chance of seeing them until they get close," says astronomer Clark Chapman of Science Applications International Corp. in Tucson, Ariz. "We could discover every asteroid and still 10 percent of the threatening objects wouldn't be found" until they were literally upon us...

...comets erupt with jets as the sun warms their surface. Like thrusters on a spaceship, the eruptions shift the comet's orbit ever so slightly. But is there reason to think Swift-Tuttle's (comet responsible for Perseid meteor showers in August) jets will push it onto a collision course?

* Truck size: Such collisions come at least every decade...

* Building size: ... Tunguska, Siberia, one June morning in 1908...

* Mountain size: Objects larger than 300 feet across hit Earth once-every 5,000 years or so...

* City size: Asteroids or comets larger than three miles across, like Swift-Tuttle, hit every 10 million to 30 million years. The impact would make entire continents burst into flame, block sunlight and make agriculture impossible. Humans might go the way of the trilobites.

...At a conference this year at Los Alamos, researchers had no shortage of ideas about how to protect against cosmic catastrophe...

...During a human lifetime, there's roughly a 1-in-10,000 chance that Earth will be hit by something big enough to wipe out crops worldwide and possibly force survivors to return to the ways of Stone Age hunter-gathers. Those are the odds of dying from anesthesia during surgery, dying in a car crash in any six-month period or dying of cancer from breathing the automobile exhaust on the Los Angeles freeway everyday. Killer asteroids and comets are out there. And someday, one will be on a collision course with Earth. Of all the species that ever crawled, walked, flew or swam on Earth, an estimated two thirds became extinct because of an impact from space. Mankind may yet meet that fate, too. But we're the only species that can even contemplate it and, just maybe, do something to prevent it.

http://www.newsweek.com/perseid-meteor-shower-2017-648114

3margd
Modificato: Apr 30, 2019, 9:35 am

What if an asteroid was about to hit Earth? Scientists ponder question
Ivan Couronne | April 30, 2019

Here's a hypothetical: a telescope detects an asteroid between 100 and 300 meters in diameter racing through our solar system at 14 kilometers per second, 57 million kilometers from Earth.

Astronomers estimate a one percent risk the space rock will collide with our planet on April 27, 2027. What should we do?

It's this potentially catastrophic scenario that 300 astronomers, scientists, engineers and emergency experts are applying their collective minds to this week in a Washington suburb, the fourth such international effort since 2013...Countries represented include China, France, Germany, Israel, Italy, Russia and the United States.

...some large ones are probably still out there: "A fair fraction of the biggest ones are hiding... basically parked behind the Sun."...Many astronomers are demanding a space telescope because terrestrial telescopes are unable to detect objects on the other side of the Sun.

Deflecting an asteroid

...global response to a catastrophic meteorite. The first step is aiming telescopes at the threat to precisely calculate its speed and trajectory, following rough initial estimates.

Then it boils down to two choices: try to deflect the object, or evacuate.

If it is less than 165 feet, the international consensus is to evacuate the threatened region. According to Koschny, it is possible to predict the country it will strike two weeks ahead. Days away from impact, it can be narrowed down to within hundreds of kilometers.

What about bigger objects? ... launch a device toward the asteroid to divert its trajectory—like a cosmic bumper car...NASA plans to test this idea out on a real asteroid 492 feet across, in 2022, with the Double Asteroid Redirection Test (DART) mission.

...Romana Kofler, of the United Nations Office for Outer Space Affairs..."Who would be the decision making authority? The consensus was to leave this aspect out."
The United Nations Security Council would likely be convened, but it's an open question as to whether rich countries would finance an operation if they themselves weren't in the sights of 2000SG344 or another celestial rock.

https://phys.org/news/2019-04-asteroid-earth-scientists-ponder.html

4RickHarsch
Mag 1, 2019, 6:39 pm

Thanks, Margd--interesting posts

5margd
Mag 4, 2019, 5:22 pm

Alternative NOAA @altNOAA | 2:14 PM - 4 May 2019

So in 10 years an #asteroid about the size of Mt. Everest is basically going to skim the top of our atmosphere (10x closer to Earth than the Moon, according to calculations) and scientists named it after the Egyptian God of Death. Nice.
_____________________________________________________________________

NASA SHOCK: Massive asteroid named after death god will shoot past Earth in a decade
Clive Hammond | May 2, 2019

New data shows that the 1,100ft-wide asteroid could fly past by 2029. Scientists have named it Apophis, after the Greek name for an Egyptian serpent god which aims to devour the sun. Research shows Apophis should miss Earth by around 19,000 miles.

However, due to the vast nature of the rock it should be seen by astronomers and other researchers.

Marina Brozović, a radar scientist at NASA's Jet Propulsion Laboratory in Pasadena, California, said: "The Apophis close approach in 2029 will be an incredible opportunity for science.

"We'll observe the asteroid with both optical and radar telescopes.

"With radar observations, we might be able to see surface details that are only a few meters in size."

The asteroid should also be visible to the naked eye.

Apophis will appear as a bright spot of light.

NASA also say it is rare for an object so big to pass by our planet.

A predictive model from NASA added: “As the asteroid passes over the Atlantic ocean, its path briefly turns from red to grey - that is the moment of closest approach.

"After closest approach, the asteroid will move into the daytime sky and will no longer be visible."

Scientists believe this will be a landmark moment in space history.

Excited conversations have been held at this week’s Planetary Defense Conference in College Park, Maryland.

Paul Chodas, director of the Center for Near Earth Objects Studies, added: “Apophis is a representative of about 2,000 currently known potentially hazardous asteroids.

"By observing Apophis during its 2029 flyby, we will gain important scientific knowledge that could one day be used for planetary defense."

https://www.express.co.uk/news/science/1121745/nasa-latest-news-asteroid-warning...

6DugsBooks
Mag 4, 2019, 6:00 pm

Just wondering if Apophis is a single rock or has a wide spread debri field traveling with it - some smaller chunks hitting the earth perhaps.

7margd
Mag 4, 2019, 6:06 pm

Oh dear...

8jjwilson61
Mag 4, 2019, 6:52 pm

Is that close enough to take out some satellites?

9prosfilaes
Mag 5, 2019, 3:38 am

>8 jjwilson61: A geostationary orbit is at 22,000 miles, so yeah, bad luck could take out one of those. Most of the other satellites, including GPS and friends, are too close to get hit, unless >6 DugsBooks: is right about a debris field, but that doesn't seem any more problematic than any meteor shower.

10margd
Giu 20, 2019, 3:15 pm

Poll: Americans Want NASA To Focus More On Asteroid Impacts, Less On Getting To Mars
Ashley Westerman | June 20, 2019

Americans are less interested in NASA sending humans to the moon or Mars than they are in the U.S. space agency focusing on potential asteroid impacts and using robots for space exploration. That's according to a poll* by The Associated Press and the NORC Center for Public Affairs Research released Thursday, one month before the 50th anniversary of the first walk on the moon.

Two-thirds of respondents said monitoring asteroids, comets and "other events in space that could impact Earth" was "very or extremely important." According to NASA, which watches for objects falling from space, about once a year an "automobile-sized asteroid hits Earth's atmosphere," but it usually burns up before it hits the surface. And the instances of larger objects actually making it past Earth's atmosphere and causing any damage happen thousands of years apart, NASA says...

https://www.npr.org/2019/06/20/734311961/poll-americans-want-nasa-to-focus-more-...

* Space Exploration: Attitudes toward the U.S. Space Program
An AP-NORC Poll conducted in May 2019 looks at perceptions of space exploration and the United States space program.
http://www.apnorc.org/projects/Pages/Space-Exploration-Attitudes-toward-the-U-S-...

11margd
Lug 25, 2019, 10:30 am

Earth had a near-miss with 'city-killer' asteroid this morning
Liam Mannix | July 25, 2019

An asteroid about 100 metres in diameter and racing at 24 kilometres a second has just missed the Earth.

The rock, called Asteroid 2019 OK, sped by our planet at 11.22am on Thursday, passing within about 70,000 kilometres – which is a long way away but closer to us than the moon’s orbit.

Due to the trajectory of the asteroid – flying towards us from the direction of the sun – astronomers had no warning it was headed our way.

It is the largest rock to fly at such close quarters to the Earth this year, and possibly for many years.

https://www.smh.com.au/national/earth-had-a-near-miss-with-city-killer-asteroid-...

12margd
Modificato: Set 7, 2019, 4:44 am

Duplicate

13margd
Set 7, 2019, 4:50 am

European Space Agency teams up with NASA for mission to deflect dangerous Earth-bound asteroids
Emma Beswick • last updated: 05/09/2019

...The ambitious, double-spacecraft mission, known as the Asteroid Impact Deflection Assessment (AIDA), will see experts from the US space agency, NASA, and the European Space Agency (ESA) come together.

...There are currently 850 "near-Earth asteroids" (NEAs) on ESA's risk list and over 18,000 known "near-Earth objects" (NEOs)

...Researchers are looking into the viability of diverting an asteroid by crashing a spacecraft into its surface, to see whether the technique is a viable method of planetary defence.

In their sights is one of two double Didymos asteroids between Earth and Mars, which they aim to deflect the orbit of using the impact of one spacecraft.

A second observer craft will survey the crash site and gather data on the effect of the collision.

The NASA and ESA teams will meet from September 11–13 and share the progress of the two AIDA spacecraft and the smaller nano-spacecraft they will carry aboard them.

NASA is contributing the Double Asteroid Impact Test (DART) spacecraft, which is set to collide with its target in September 2022 at a speed of at 6.6 km/s. It is already under construction.

The moment of impact will be recorded by an Italian-made miniature CubeSat called LICIACube.

ESA will launch a Hera probe in October 2024 to study the target asteroid post-impact.

...(hopefully) a technique that could be repeated were there a real threat.

( 2:45 video: https://www.youtube.com/watch?v=jA3nBSIf4-g )
https://www.euronews.com/2019/09/05/european-space-agency-teams-up-with-nasa-for...

14margd
Feb 17, 2020, 9:13 am

All Known Asteroids in the Solar System (1999-2018) (0:55)
NASA Jet Propulsion Laboratory • Jul 23, 2018

This animation represents a map of the increased count of all known asteroids in the solar system between Jan. 1, 1999, and Jan. 31, 2018.
Blue represents near-Earth asteroids. Orange represents main-belt asteroids between the orbits of Mars and Jupiter.
For more info about how NASA tracks and studies asteroids and comets, visit https://www.jpl.nasa.gov/asteroidwatch/ and https://cneos.jpl.nasa.gov/ .

https://www.youtube.com/watch?v=vfvo-Ujb_qk

15margd
Feb 20, 2020, 10:02 am

What should we do if a 'planet-killer' asteroid takes aim at Earth? (01:30)
Rafi Letzter - 2/20/2020

Researchers at MIT calculated which option is best depending on the asteroid and its path through space.

If a giant object looks like it's going to slam into Earth, humanity has a few options: Hammer it with a spacecraft hard enough to knock it off course, blast it with nuclear weapons, tug on it with a gravity tractor, or even slow it down using concentrated sunlight.

We'll have to decide whether to visit it with a scout mission first, or launch a full-scale attack immediately.

Those are a lot of decisions to make under existential duress, which is why a team of MIT researchers have come up with a guide, published February in the journal Acta Astronautica, to help future asteroid deflectors....*

https://www.livescience.com/how-to-stop-asteroid-from-hitting-earth.html

_______________________________________________

* Olivierde Wecka et al. 2020. Optimization and decision-making framework for multi-staged asteroid deflection campaigns under epistemic uncertainties. Acta Astronautica Volume 167, February 2020, Pages 23-41, https://doi.org/10.1016/j.actaastro.2019.10.042. https://www.sciencedirect.com/science/article/abs/pii/S0094576519313700?via%3Dih...

Highlights
• We model near-Earth asteroid (NEAs) mitigation campaigns under uncertainties.
• Precursors reduce the kinetic impact uncertainties at the cost of time and mass.
• Different types of precursors, including a non-precursor option, are considered.
• Stochastic optimization and robustness quantifications are performed concurrently.

Abstract
In this study, we introduce a framework for planning and assessing multi-spacecraft asteroid deflection campaigns. In the scenario considered, a near-Earth asteroid (NEA) is nudged away from gravitational keyholes via a kinetic impactor (KI) technique, lest its passage should incur an Earth collision in the future. An asteroid orbiter or/and an impactor is/are used in the precursor stage to obtain uncertain information about the target asteroid, whose launch date and trajectory are optimized using Chebyshev's method and a genetic algorithm. The KI mass is optimized through Monte Carlo simulations to improve the robustness of the method and achieve the minimum required probability of success (PoS). Case scenarios targeting Apophis and Bennu substantiate the utility of the framework in optimizing different deflection campaign architectures and making decisions amongst them via newly proposed visualization methods.

16margd
Nov 19, 2020, 8:11 am

Near miss: House-sized asteroid skimmed Earth at 250 miles on Friday the 13th
Theresa Braine 9 hrs ago

While everyone was looking over Earth’s collective shoulder toward the asteroid that was potentially going to whiz past us the day before Election Day, an entirely different one came at us via our blind spot — the direction of the sun.

It passed a mere 239 miles or so from Earth, skimming the tip-top part of our atmosphere — on Friday the 13th.

And no one noticed until the next day, when 15 hours later it was detected by the Asteroid Terrestrial-impact Last Alert System survey at the Mauna Loa Observatory in Hawaii.

The Election Day one was the size of a fridge, as astrophysicist Neil DeGrasse Tyson said in raising the alarm at the time. But in the end that one barely nicked Earth’s orbit, let alone our atmosphere.

Asteroid 2020 VT4 is another story. An estimated 16-32 feet across, “about the size of a small house,” according to Universe Today, it set a record for the “closest documented non-meteoric asteroid pass versus the Earth.”

Traveling at 30,014 miles per hour, it whizzed past us over the South Pacific at 12:20 p.m. Eastern Time last Friday, EarthSky.org reported...

...astronomers agree that even if it had come within the 50 to 70 miles above Earth’s surface, where most such space rocks break up, it wouldn’t have done anything more than disintegrate — though it would have been an impressive meteor even in broad daylight, EarthSky noted....

https://www.msn.com/en-us/news/technology/near-miss-house-sized-asteroid-skimmed...

17margd
Apr 9, 2021, 8:12 am

Harvard University Harvard | 9:55 PM · Apr 8, 2021:
Where did the asteroid or comet that killed the dinosaurs come from, and how did it end up hitting Earth?
A pair of Harvard researchers may have the answer:
Origin of the Armageddon causing comet
A new theory from Avi Loeb and Amir Siraj explains the origin of the comet that killed the dinosaurs.
4:02 ( https://twitter.com/Harvard/status/1380338423261659137 )
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The cataclysm that killed the dinosaurs
Juan Siliezar | February 15, 2021

New theory explains possible origin of plummeting Chicxulub impactor that struck off Mexico

...Using statistical analysis and gravitational simulations, Loeb and Siraj say that a significant fraction of a type of comet originating from the Oort cloud, a sphere of debris at the edge of the solar system, was bumped off-course by Jupiter’s gravitational field during its orbit and sent close to the sun, whose tidal force broke apart pieces of the rock. That increases the rate of comets like Chicxulub (pronounced Chicks-uh-lub) because these fragments cross the Earth’s orbit and hit the planet once every 250 to 730 million years or so...

https://news.harvard.edu/gazette/story/2021/02/new-theory-behind-asteroid-that-k...

----------------------------------------------------

Amir Siraj & Abraham Loeb. 2021. Breakup of a long-period comet as the origin of the dinosaur extinction. Scientific Reports volume 11, Article number: 3803 (2021) https://www.nature.com/articles/s41598-021-82320-2

Abstract

The origin of the Chicxulub impactor, which is attributed as the cause of the K/T mass extinction event, is an unsolved puzzle. The background impact rates of main-belt asteroids and long-period comets have been previously dismissed as being too low to explain the Chicxulub impact event. Here, we show that a fraction of long-period comets are tidally disrupted after passing close to the Sun, each producing a collection of smaller fragments that cross the orbit of Earth. This population could increase the impact rate of long-period comets capable of producing Chicxulub impact events by an order of magnitude. This new rate would be consistent with the age of the Chicxulub impact crater, thereby providing a satisfactory explanation for the origin of the impactor. Our hypothesis explains the composition of the largest confirmed impact crater in Earth’s history as well as the largest one within the last million years. It predicts a larger proportion of impactors with carbonaceous chondritic compositions than would be expected from meteorite falls of main-belt asteroids.

18margd
Mag 3, 2021, 5:28 pm

Large Chunk Of Europe "Annihilated" In NASA's Latest Asteroid Impact Simulation Exercise

Every two years, international governmental and space agencies take part in a tabletop scenario as part of the Planetary Defense Conference. In this exercise, a space rock is discovered to be heading toward Earth and members of different agencies have to work out what are the best things to do to try and avoid catastrophe....

Today We Are Not Ready. Maybe, Tomorrow

Over the years, these simulations have shown what we are doing well and what we are doing not so well, and where we are dangerously unprepared. Many aspects of the 2021 Planetary Defense Conference fall in the latter category.

The briefs show that if such an object were to be discovered today or tomorrow, we would struggle to protect the planet. In 2019, a 100-meter (330-foot) long asteroid called 2019 OK was only discovered one month before it passed 72,500 kilometers (45,000 miles) from our planet.

Observatories such as the Vera Rubin, and many others, will help to discover more of these objects (if they are not too affected by satellites megaconstellations like Starlinks) but more is needed to keep our planet safe. The simulation actually points out that if the Rubin Observatory had been online in 2014, it would have spotted the fictional 2021 PDC.

The chances of a truly dangerous asteroid hitting our planet remain astronomically low but when it comes to the risk they pose, we ought to be prepared. And we are not.

https://www.iflscience.com/space/large-chunk-of-europe-annihilated-in-nasas-late...

19margd
Mag 13, 2021, 7:38 am

Here's How Many Years in Advance We'd Need to Stop a Killer Asteroid Coming For Earth
MORGAN MCFALL-JOHNSEN & AYLIN WOODWARD | 13 MAY 2021

...In reality, if an asteroid like that fictional one were heading for Earth, scientists would need years – not months – of warning. Five years is the minimum, according to Chodas. Others, like MIT astronomer Richard Binzel, say we'd need at least a decade.

...But scientists haven't identified most of the hazardous space rocks that pass near our planet, which makes the chances slim that we'd get a five- or 10-year warning period. In 2005, Congress attempted to address this issue by mandating that NASA find and track 90% of all near-Earth objects 140 meters (460 feet) or larger. At that size, asteroids could obliterate a city the size of New York. But to date, NASA has only spotted about 40% of those objects.

"What that means is, for now, we are relying on luck to keep us safe from major asteroid impacts," Binzel said. "But luck is not a plan." ...

https://www.sciencealert.com/here-s-how-many-years-in-advance-we-d-need-to-stop-...

20DugsBooks
Mag 14, 2021, 8:21 pm

>19 margd: I saw a condensed version of that report - stating the 10 year lead we would need. Thanks for posting. Maybe the Hubble scope could be upgraded by an Elon Musk rocket & augmented for asteroid detection.

21margd
Lug 7, 2021, 12:15 pm

In the future, Earth may not be in any danger from asteroids. Chinese researchers to use rockets to deflect them
Reuters | Jul 07, 2021

...Chinese researchers want to send more than 20 of China's largest rockets to practice turning away a sizable asteroid - a technique that may eventually be crucial if a killer rock is on a collision course with Earth.

...At China's National Space Science Center, researchers found in simulations that 23 Long March 5 rockets hitting simultaneously could deflect a large asteroid from its original path by a distance 1.4 times the Earth's radius.

Their calculations are based on an asteroid dubbed Bennu, orbiting the sun, which is as wide as the Empire State Building is tall. It belongs to a class of rocks with the potential to cause regional or continental damage. Asteroids spanning more than 1 km would have global consequences....

https://economictimes.indiatimes.com/magazines/panache/in-the-future-earth-may-n...
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Yirui Wang , Mingtao Li et al. 20210 Assembled kinetic impactor for deflecting asteroids by combining the spacecraft with the launch vehicle upper stage. Icarus Volume 368, 1 November 2021, 114596
https://doi.org/10.1016/j.icarus.2021.114596

Highlights

• The launch vehicle upper stage can be used as a payload to improve the mass of the impactor, thereby improving the deflection efficiency of the kinetic impactor strategy.
• Compared with the Classical Kinetic Impactor (CKI, with spacecraft-rocket separation), results show that the Assembled Kinetic Impactor (AKI, without spacecraft-rocket separation) increases the deflection distance by more than 3 times.
• The technical feasible of the AKI concept is preliminarily discussed.

Abstract
Asteroid impacts pose a major threat to all life on Earth. Deflecting an asteroid on an impact trajectory is critical to mitigating this threat. A kinetic impactor remains the most feasible asteroid deflection method. However, due to launch capability constraints, an impactor with a limited mass can only minimally change the velocity of an asteroid. To improve the deflection efficiency of the kinetic impactor strategy, this paper proposes the Assembled Kinetic Impactor (AKI), which combines the spacecraft with the launch vehicle upper stage. After the launch vehicle upper stage sends the spacecraft into an Earth-escaping trajectory, the spacecraft-rocket separation is not performed, and the spacecraft controls the AKI to impact the asteroid. By retaining the mass of the launch vehicle upper stage, the mass of the impactor is increased, thereby enhancing the deflection efficiency. According to the technical data of the Long March 5 (CZ-5) launch vehicle, missions to deflect Bennu are designed to demonstrate the power of the AKI concept. Simulation results of the AKI compared with the Classical Kinetic Impactor (CKI, with spacecraft-rocket separation) show that the addition of the mass of the upper stage increases the deflection distance by >3 margd: times. To achieve a given deflection distance, the addition of the upper stage mass reduces the number of launches to 1/3 that of the number of CKI launches. The AKI concept makes it possible to deflect large Bennu-like asteroids with a nuclear-free technique with a 10-year launch lead time. Additionally, with a single CZ-5, the deflection distance of a 140-m-diameter asteroid with a 10-year launch lead time increases from less than 1 to more than 1 Earth radius, representing an improvement in the reliability and efficiency of asteroid deflection missions.

22margd
Ago 13, 2021, 9:23 am

So after we've taken care of COVID and global warming...

NASA ups the odds of Bennu asteroid hitting Earth
By Caroline Vakil - 08/12/21

...Scientists previously said that the odds that Bennu would strike the Earth into 2200 was one-in-2,700, but those figures were adjusted to one-in-1,750 into the year 2300...

...if the Earth was struck by the asteroid, the amount of area destroyed would equal the asteroid’s size one hundred fold...If the asteroid hit the East Coast of the U.S., it “would pretty much devastate things up and down the coast,” (Planetary defense officer for NASA, Lindley Johnson) added.

https://thehill.com/policy/energy-environment/567698-nasa-ups-the-odds-of-bennu-...

23Limelite
Ago 13, 2021, 2:16 pm

>22 margd:

That's the bad news. The good news is it would probably cool the Earth significantly.

24margd
Ago 30, 2022, 5:44 am

Sept 26, 2022. 7:14 pm

Mark Your Calendars: NASA Will Livestream First Attempt To Knock An Asteroid Off Its Path
Devan McGuinness | 8.27.2022

DART is a mission created to test the idea that shooting a space rock, and hitting it hard enough, will deflect it from its path towards Earth. The best part? We get to watch.

...Didymos B's proximity to Earth makes it the perfect test asteroid to see if NASA's plan to nudge an asteroid off its path will work. "This test will show if we're ready to take on any threatening asteroids that could be headed our way," EarthSky explains.

The mission to impact and move Didymos B will happen on Sept. 26, 2022, at 7:14 pm EST, so mark your calendars.

How to watch the DART's first attempt
Since this will be the world's first attempt, and because it's really cool, the DART mission will be viewable live by the public. Coverage will start at 6 pm EST on Sept. 26 and it will be streamable on NASA's website (https://www.nasa.gov/nasalive/), but it will also be viewed on YouTube, Twitter, and Facebook.

For more details about the mission, check out NASA's website...

https://www.fatherly.com/news/mark-your-calendars-nasa-will-livestream-its-first...

25margd
Modificato: Ott 11, 2022, 4:46 pm

Benjamin Wittes (Lawfare) @benjaminwittes | 10:34 PM · Sep 22, 2022:
This is my kind of NASA mission!
Let get that asteroid!

Quote Tweet
The Associated Press AP | 10:23 AM · Sep 22, 2022

In the first-of-its kind experiment, NASA is about to clobber a small, harmless asteroid millions of miles away to change its path slightly.

If successful, the test will show that if a killer asteroid ever heads for Earth, there'd be a fighting chance.

1:14 ( https://twitter.com/AP/status/1572954620317470721 )
______________________________________
ETA

The DART mission successfully changed the motion of an asteroid
Ashley Strickland | October 11, 2022

...The DART spacecraft changed the moonlet asteroid’s orbit by 32 minutes.

Initially, astronomers expected DART to be a success if it shortened the trajectory by 10 minutes...

https://www.cnn.com/2022/10/11/world/nasa-dart-success-update-scn/index.html

26margd
Mar 2, 2023, 11:17 am

DART's epic asteroid crash: What NASA has learned 5 months later
Sharmila Kuthunur | 1 March 2023

NASA's Double Asteroid Redirection Test (DART) mission had two main goals: to show that an asteroid could be targeted in a high-speed encounter, and to demonstrate that the target's orbit could be changed — a technique astronomers hope to use for planetary defense should a dangerous space rock come our way.

"DART has successfully done both," astronomers report in a new study*. The mission's resounding success shows that a "kinetic impactor" like DART is a "viable technique to potentially defend Earth if necessary," researchers note in another new study**.

Those two studies are part of a raft of five DART papers published online Wednesday (March 1) in the journal Nature. In the five studies, astronomers shared additional findings from the mission using data the probe sent home up in the leadup to its colllision with Dimorphos, a moon of the 2,560-foot-wide (780 meters) asteroid Didymos, on Sept. 26, 2022, and in the crash's aftermath...

https://www.space.com/nasa-dart-asteroid-crash-what-nasa-learned
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* https://www.nature.com/articles/s41586-023-05805-2.epdf

** https://www.nature.com/articles/s41586-023-05810-5.epdf