1.2 km - 2.7 km Earth approaching object on Jan 25.

Soruce:
hisz.rsoe.hu...
(bottom of the page).

This one is not coming close to Earth, we talk about 25 lunar distances however I find it interesting / worth mentioning as we do not have 1-2 mile long asteroids passing by every day.

reply to post by Romanian

Yeah thats a big sucker alright,glad its not coming to close do you know if its going to be visible? It would be interesting to watch out for.
Im sure Phage will have some good imfo on it

reply to post by Romanian


I'd like to thank you for not saying "OMG THIS COULD BE IT FOLKS!!!!" and letting everyone know that it's not coming that close.

Thank you so much.

And also thank you for bringing it to my attention. Pretty big.

love your post OP. and yes on the fear mongering comment.
that is a huge projectile. that would create quite an impact if it were to happen.

wondering if it has any satellites? several out there do.

reply to post by zooplancton

Thank you ! if we had 1 Lunar Distance I would have panic lol , but 25 is more than safe. The relative velocity to us is about 31 km per second, quite normal.

I found an impact calculator here (if something like this would ever hit the Earth):
calc

My input:

Distance from Impact: 1000.00 km ( = 621.00 miles )
Projectile diameter: 2.70 km ( = 1.68 miles )
Projectile Density: 3000 kg/m3
Impact Velocity: 31.00 km per second ( = 19.30 miles per second )
Impact Angle: 30 degrees
Target Density: 2500 kg/m3
Target Type: Sedimentary Rock

The output:

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

Energy:
Energy before atmospheric entry: 1.49 x 1022 Joules = 3.55 x 106 MegaTons TNT
The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 1.2 x 107years

Major Global Changes:
The Earth is not strongly disturbed by the impact and loses negligible mass.
The impact does not make a noticeable change in the tilt of Earth's axis (< 5 hundreths of a degree).
The impact does not shift the Earth's orbit noticeably.

Crater Dimensions:
What does this mean?


Transient Crater Diameter: 26.6 km ( = 16.5 miles )
Transient Crater Depth: 9.41 km ( = 5.84 miles )

Final Crater Diameter: 41 km ( = 25.5 miles )
Final Crater Depth: 905 meters ( = 2970 feet )
The crater formed is a complex crater.
The volume of the target melted or vaporized is 65.7 km3 = 15.8 miles3
Roughly half the melt remains in the crater, where its average thickness is 118 meters ( = 388 feet ).

Thermal Radiation:
What does this mean?


The fireball is below the horizon. There is no direct thermal radiation.

Seismic Effects:
What does this mean?


The major seismic shaking will arrive approximately 3.33 minutes after impact.
Richter Scale Magnitude: 9.0
Mercalli Scale Intensity at a distance of 1000 km:

III. Felt quite noticeably by persons indoors, especially on upper floors of buildings. Many people do not recognize it as an earthquake. Standing motor cars may rock slightly. Vibrations similar to the passing of a truck.

IV. Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.


Ejecta:
What does this mean?


The ejecta will arrive approximately 8.24 minutes after the impact.
At your position there is a fine dusting of ejecta with occasional larger fragments
Average Ejecta Thickness: 4.48 mm ( = 1.76 tenths of an inch )
Mean Fragment Diameter: 604 microns ( = 23.8 thousandths of an inch )


Air Blast:
What does this mean?


The air blast will arrive approximately 50.5 minutes after impact.
Peak Overpressure: 16900 Pa = 0.169 bars = 2.39 psi
Max wind velocity: 37.1 m/s = 83.1 mph
Sound Intensity: 85 dB (Loud as heavy traffic)
Damage Description:


Glass windows will shatter.

reply to post by Romanian


thanks for posting this. a 9.0 EQ is pretty intense.
hoping I never see a direct impact.

Can it have any effect on our magnetic field or interfere in any other way - even though it's not going to impact directly?

I haven't a clue and trust some one has! But saying that - the Science got all confused about the unexpected survival of Lovejoy so no, I don't have much faith in them either.

Yes, hopefully Phage will drop by and give us our opinion.

WHERE ARE YOU PHAGE?!?!?!?

What does everyone need Phage's opinion for?

Someone just posted the impact info if anything like this ever did hit us, and we know this one won't.

What information are you guys actually asking for from Phage that you couldn't get by a simple google search?

Geez post it here with a link and no Phage will be needed.

P.S. Back on topic...

It will be nice for scientists to have this one so close that we will be able to gather a lot of scientific information from it. Maybe it will help us for the future when we bring them in orbit to mine them.

Great OP. S&F.

Pred...

echo.jpl.nasa.gov...

Background


(7341) 1991 VK was discovered by Eleanor F. Helin and Kenneth J. Lawrence on November 1, 1991 from Palomar Observatory. 1991 VK is a PHA that we previously observed on two occasions with radar. The first was in January 1997 with Goldstone (CW and ranging, Ostro et al., 1998) and the second was in January of 2007 with Arecibo. This object has a 4.2-h rotation period (Pravec et al., 1998) and is ~1.4 km in diameter. To date, the best resolution achieved by radar was 1 usec (150 m).

1991 VK approaches Earth at 25 lunar distances (LD) on Jan. 25, 2012, and we will observe it at Goldstone in the week prior to the closest approach. 1991 VK will be a relatively weak target at Goldstone, although we expect to obtain some 1 usec (150 m) images. This object will also be observed at Arecibo on Jan. 4-6, where we hope to image it with 0.2 usec (30 m) resolution. All of the Goldstone observations occur after 1991 VK moves too far southfor Arecibo to track.

1991 VK becomes a day-time object in early January, and it becomes observable again with optical telescopes in the southern hemisphere in the second part of February.

A little bit of info...

Pred...

reply to post by quedup


There is no magnetic field around asteroids, Mars itself barely has a faint magnetic field you know why? There is no solid core inside a highly molten interior to create it for Mars because it's virtually tectonically inactive, so a tiny asteroid could not have such a thing for the last 4 and a half billion years, this thing drifts out 2/5ths of the way to Jupiter from Mars so I'm confident it's a solid cold rock.

Myself I don't consider an approach over 6 million miles away close. The body crossed earth's orbit Dec.16th at .2 AU distant, not accounting for how far above our ecliptic is was, its only going to be closer to earth Jan. 22nd because its beside earth's orbit just after where its orbital plane crosses our ecliptic, then it will cross our orbit below our orbital ecliptic about .14 AU away not accounting for the distance it is below us around Feb. 21-22.. So apparently this body even in the future has no real chance of ever colliding with earth, as it will cross again in Jan. 2014, with earth on the other side of the sun.

All this is, is a chance for a relatively close observational opportunity.

Use JPL small body browser to get an estimate orbital diagram.

Phage dependency?

Phage, I know you'll read this. Do you wonder why we ask for you, even after we have everything figured out?? I wonder the same.

-"Hey look at that sun."
+"Damn, that sun sure is bright."
-"Let's ask Phage what he thinks."

reply to post by predator0187


Dude trust me, I have been asking this question for a long time now.
It is a phenomenon.
I decided to stop trying to swim upstream and finally break down and get on the Phagewagon!!
Hop on won't ya??

Nice...scare people with the title.I ibet you enjoyed terrifing people.

Originally posted by Bilder
reply to post by Romanian

 

Yeah thats a big sucker alright,glad its not coming to close do you know if its going to be visible? It would be interesting to watch out for.
Im sure Phage will have some good imfo on it

edit on 28-12-2011 by Bilder because: (no reason given)

Why is it i always see you and others reply with

"wait until the mighty phage appears he will solve" lol


There are many smart members on here (I am not 1 of them at all) but there a few others i see post just as much or more info than phage.

Nothing against you either phage. I just dont like @ss kissers.


Carry on...

reply to post by Bilder

Yeah thats a big sucker alright,glad its not coming to close do you know if its going to be visible? It would be interesting to watch out for.

It will have an apparent magnitude of 16.5, so you would need an extremely powerful telescope to actually see it with your eyes.

ssd.jpl.nasa.gov...

reply to post by Romanian


I was glad to see someone take the time to do the math on this one.

I am courious though about the possibility of a change in velocity once such an object came onto a collision course with the earth. I would think it's speed would increase as it began to get closer and the gravitation attraction became stronger.

If this were true, the effects of an impact would increase proportionally.

I am not questioning the work you have done. I just thought, if true, this might be something you had not considered.

reply to post by hdutton


Hello. Sorry if some people got panicked, I did mention in the OP - this passes 25 lunar distances away from us. From the threat point of view - this is VERY VERY FAR. From the astronomy point of view, it is an opportunity if you can see it with the average back-yard telescope.

The calculations were made for the question "what if something like this would hit the earth" , yet we see it would have just local implications.

About the capability to change the path of such object : I believe this would be possible with some patience, using inertial devices. Another subject here.

In regards to calling Phage - well, he does know a lot however if you have patience and know how to use Google you could go quite far yourself without needing expert advice. Wikipedia is a great start !

O, an additional note. I did not do the calculations myself, you can find the calculators online, look for "online asteroid impact calculator " . I just used work done by others hehe.

reply to post by hdutton


It's a calculator, I'm not sure how much atmospheric drag is factored into the impact speed, but atmospheric drag is in the calculations, it doesn't forget about it. Gravity would be negligible at the speeds the bodies are traveling. If you looked at the OP's link, this particular asteroid is among the slowest, maybe second slowest of all listed. By the time it ever gets close to earth, inside earth's orbit the sun has more gravitational effect than earth, it can never collide with earth in it's current orbit, it also can't collide with Mars, it would have to be struck by a huge comet to change its orbit. See my above JPL orbital diagram applet.

reply to post by Illustronic


So, if I am moving at two miles per hour when I run off a three thousand foot bluff. I will still be moving at two miles per when I land at the bottom.

This would be survivable, as apposed to the speed I would have reached if the law of gravity had not been repealed. I think it said something about some acceleration as two objects drew closer together.

But what do I know? This was the basis of my question "IF " an object were to move into a collision course with earth?