Question Asteroid impacts?

[North]

If asteroid 2024 YR4 hits Earth will there be any survivors? and what is the most likely location for it to hit?
If asteroid 101955 Bennu dose hit earth were will it hit? and will any life survive?

 

[George²]

If asteroid 2024 YR4 hits Earth will there be any survivors? and what is the most likely location for it to hit?

It's too small. Maybe will kill around 1000 if hit town with high density population.
In same scenario Benny will kill millions if hit big town.
Not any global impact. Benny also is too small.

 

[Ken Fabian]

Even Chicxulub - much larger than either of those - could not wipe out life on Earth. It caused mass extinctions of many existing species, yes, but many survived. 2024 YR4 is estimate at between 40 and 90 m diameter. Bennu (known Earth orbit crossing orbit, but not on a collision course) is a bit under 500 m. Neither would be good for anyone in the vicinity - major destruction to a town for the smaller one, major destruction to a city for the latter, plus air shock waves blowing out eardrums and windows over large areas.

 

[Classical Motion]

If we can bust a rock up enough, even a large one, and increase it's surface area, the air will burn it up. It's just has to be fine enough.

 

[Ken Fabian]

If we can bust a rock up enough, even a large one, and increase it's surface area, the air will burn it up. It's just has to be fine enough.

That could work for smaller objects, especially "loose rubble piles" and the further away it is done the better, preferably far enough that most of it doesn't hit the Earth or atmosphere at all. One of the reasons early warning is so important.

It won't work for larger ones closer to Earth; the amount of material can be so large it heats the atmosphere, dangerously, even where few pieces are big enough to reach the surface. Not sure about risks to satellites, ISS etc with a disrupt and explosively disperse approach. Diverting them is the other approach, again best done early.

I expect it will be on a case by case basis. It does seem like NASA is looking for potential collisions in every asteroid's orbital characteristics, looking many orbits into the future; this is for the bigger ones. Lots of time to act. The smaller ones only seen as they approach don't give much time. Anything large from outside the solar system will be a serious problem, likely higher speeds and harder to determine their trajectory until already close - but those are exceptionally rare.

Bennu's track is probably known better than any other asteroid courtesy of Osiris-Rex mission and isn't a danger. 2024 YR4 needs some dedicated observation to track it's trajectory more accurately. Most on the danger list get crossed off with more accurate tracking.

The options seem to be deflection or disruption - and possibly combinations like blowing out material directionally to deflect. For energy delivery nuclear weapons give the most. For rockets used for pushing or pulling (gravity tractor) the rocket power needed and amounts of fuel get very, very large. Current rocketry would be struggling to deliver a few warheads but seems achievable. The rockets and fuel for pushing/pulling millions of tons looks far beyond our capabilities.

If 2024 YR4 does turn out to be on a collision course I think we are not well prepared and even a crash program (hah) would struggle.

Planetary meteor defense that will be effective is a long term objective that is, by itself, extraordinarily ambitious, requiring ongoing improvements in rocketry and space based capabilities and international cooperation - but one actual impact of significance would be a big wake up call. I think colonizing anywhere is getting ahead of our selves but pushing ahead towards effective planetary defense will always make sense.

 

[North]

thank you for this very helpful
what are the current possible impact loctions for Bennu

 

[Ken Fabian]

I have seen a 1 in 2700 chance of Bennu colliding with Earth in (I think) 2170. (An article on space.com?).That seems like enough time to pin down the trajectory more accurately and plan responses if Bennu is not crossed off the list. Odds are it will be crossed off the list but it is better to keep improving observation as well as develop responses.

Important to note that without high confidence of an impact any premature attempts to change the trajectory will be guesswork - and may turn a near miss into a hit unless the trajectory is changed by a lot. I expect the ability to divert them will remain limited and big changes will present big challenges.

 

[Catastrophe]

Even Chicxulub - much larger than either of those - could not wipe out life on Earth. It caused mass extinctions of many existing species, yes, but many survived. 2024 YR4 is estimate at between 40 and 90 m diameter. Bennu (known Earth orbit crossing orbit, but not on a collision course) is a bit under 500 m. Neither would be good for anyone in the vicinity - major destruction to a town for the smaller one, major destruction to a city for the latter, plus air shock waves blowing out eardrums and windows over large areas.

Great to see you posting! Just a few words from Wiki and Britannica on the K/T extinctions:

Cretaceous–Paleogene extinction event - Wikipedia

en.wikipedia.org

K–T extinction | Overview & Facts | Britannica

K–T extinction, a global extinction event responsible for eliminating approximately 80 percent of all animal species about 66 million years ago. It was characterized by the purging of many lines of animals that were important, including nearly all of the dinosaurs and many marine invertebrates.

www.britannica.com

I just think "mass extinctions of many existing species" is slightly understating the issue.
Whilst it did notcompletely wipe out life on Earth, something like 75% to 80% of animal and plant species disappeared. If not mankind, certainly civilisation would be wiped out. It is difficult to overestimate the results of greatly reducing sunlight on food chains.

Cat

 

[EL PIC]

thank you for this very helpful
what are the current possible impact loctions for Bennu

As of February 2025 they keep lowering the probability and now well less than 1% with expected splash down between Africa and South America.
If anything it will be a big splash from a tinny rock.

 

[North]

yes I just saw that the chance of it hitting Earth is now 1 in 360 or 0.3 %

 

[EL PIC]

They might be lying to reduce fear