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Asteroid Will Pass 25,000 Miles From Earth On Sunday


Monroe

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They keep coming ... just discovered on August 31st.

 

 

NASA: Asteroid Will Pass ‘Very Close’ To Earth On Sunday

 

http://tampa.cbslocal.com/2014/09/04/nasa-asteroid-will-pass-very-close-to-earth-on-sunday/

 

September 4, 2014

 

TAMPA, Fla. (CBS Tampa) — NASA announced that a small asteroid will safely pass “very close” to Earth on Sept. 7.

 

The asteroid, designated 2014 RC, will be roughly over New Zealand at the time of closest approach, which will be about 2:18 pm EDT based on current calculations. Astronomers estimate that the asteroid is about 60 feet in size.

 

On the night of Aug. 31, the asteroid was first discovered by the Catalina Sky Survey near Tucson, Ariz., and was detected independently the next night by the Pan-STARRS 1 telescope that is located in Hawaii.

 

The orbit of 2014 RC was confirmed by both the Catalina Sky Survey and the University of Hawaii during follow-up observations.

 

t will be about 25,000 miles away at the time of its closest approach to Earth. It won’t be observable to the unaided eye, but amateur astronomers with small telescopes might be able to spot the fast-moving appearance of the asteroid.

 

The asteroid doesn’t seem to pose any threat to Earth or satellites in space. It will prove to be an opportunity for researchers to observe and gather more information about asteroids.

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Possibly a small piece of the asteroid from the Sunday fly-by may have hit the Earth ... pretty good explosion from that small piece, wherever it came from. The whole asteroid was considered "small" and this maybe was just a piece.

 

'Meteorite' Smashes Into Nicaraguan Capital

 

http://news.yahoo.com/meteorite-smashes-nicaraguan-capital-230034550.html

 

2 hours ago - 08 September 2014

 

Managua (AFP) - A mysterious explosion that rocked Nicaragua's crowded capital Managua, creating a large crater, appears to have been caused by a small meteorite, officials said Sunday.

 

Amazingly, in a sprawling city of 1.2 million people, the impact near the international airport did not cause any known injuries, but it did leave a crater measuring 12 meters (39 feet) across and was felt throughout the capital late on Saturday.

 

Nicaraguan authorities believe it was a piece of the small asteroid dubbed "2014 RC," which passed very close to Earth on Sunday and was estimated by astronomers to be about 20 meters big, or the size of a house.

 

"We are convinced that this was a meteorite. We have seen the crater from the impact," said Wilfredo Strauss of the Seismic Institute.

 

The meteorite appeared to have hurtled into a wooded area near the airport around midnight and the hit was so large that it registered on the instruments Strauss's organization uses to size up earthquakes.

 

"You can see two waves: first, a small seismic wave when the meteorite hit earth, and then another stronger one, which is the impact of the sound," he said.

 

Government officials and experts visited the impact site on Sunday.

 

One of them, William Martinez, said it was not yet clear if the meteorite burned up completely or if it had been blasted into the soil.

 

"You can see mirror-like spots on the sides of the crater from where the meteorite power-scraped the walls," Martinez said.

 

Government spokeswoman, First Lady Rosario Murillo, said Managua would be in contact with the US Geological Service to try to get more information about "this fascinating event" in the Central American nation, one of Latin America's poorest countries.

 

People who live near the crater told local media they heard a blast they took for an explosion, and that liquid, sand and dust were blown through the air, which smelled like something had burned.

 

There were no reported injuries because the impact was in a wooded spot, and flights at the airport were not affected.

 

NASA said last week that the asteroid 2014 RC, at the time of closest approach, would be approximately one-tenth the distance from the center of Earth to the moon, or about 25,000 miles (40,000 kilometers).

 

It had been projected to be roughly over New Zealand at the time of its closest approach, which astronomers had calculated would be on Sunday at about 1818 GMT.

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....

"We are convinced that this was a meteorite. We have seen the crater from the impact," said Wilfredo Strauss of the Seismic Institute.

 

....

One of them, William Martinez, said it was not yet clear if the meteorite burned up completely or if it had been blasted into the soil.

...

Or if by appropriate use of  "magic" the meteorite disappeared (and is going to re-materialize itself soon as an item for sale on e-bay ) :whistle:

 

jaclaz

Edited by jaclaz
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Its authenticity, however, will be real hard to prove, because any bean-sized quartz or metal droplet should be enough to cause a 12 m crater and, being already hot from the plunge in Earth's atmosphere, it really might be vaporized on impact and, well, "disappear"... :D

 

What size crater should be expected for, say, a baseball ball hitting the dirt at the full speed 2014 RC's travelling at?

Surely way more than 12 m, in my opinion...

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It's authenticity, however, will be real hard to prove, because any bean-sized quartz or metal droplet should be enough to cause a 12 m crater and, being already hot from the plunge in Earth's atmosphere, it really might be vaporized on impact and, well, "disappear"...  :D

Sure :), but - by the same token - can also be recreated, so I wouldn't be surprised is several specimens would "re-appear" for sale. 

 

 

 

What size crater should be expected for, say, a baseball ball hitting the dirt at the full speed 2014 RC's travelling at?

Surely way more than 12 m, in my opinion...

Try using the very convenient Computing Crater Size from Projectile Diameter online calculator :w00t: :

http://www.lpl.arizona.edu/tekton/crater_c.html

 

 

jaclaz

Edited by jaclaz
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There was a large meteor/asteroid that hit Arizona around 50,000 years ago. It is called Meteor Crater and there was never a meteorite found. Several theories exist that it vaporized, exploded or bounced into the Pacific Ocean ... at least those theories were around in the 50s and 60s.

 

http://meteorcrater.com/

 

Meteor Crater is nearly one mile across, 2.4 miles in circumference and more than 550 feet deep. It is an international tourist venue with outdoor observation trails, air conditioned indoor viewing, wide screen movie theater, Interactive Discovery Center, unique gift and rock shop, and Astronaut Memorial Park at the Visitor Center located on the crater rim.

 

Mystery of Arizona's Meteor Crater Solved

 

http://www.space.com/834-mystery-arizona-meteor-crater-solved.html

 

The space rock that carved Meteor Crater in Arizona hit the planet much more slowly than astronomers once figured, but still 10 times faster than a rifle bullet.

 

The new analysis, announced today, explains why there's a lot less melted rock in the crater than expected. The mystery has dogged researchers for years.

 

The big hole in the ground -- 570 feet deep and 4,100 feet (1.25 kilometers) across -- was blown into existence 50,000 years ago by an asteroid roughly 130 feet (40 meters) wide.

 

Previous calculations had the rock slamming into the ground at no less than 34,000 mph (15 km/sec), based in part on the expected speeds of large meteors in relation to Earth. Such an impact ought to have generated more melted rock in and around the crater than what's been found.

.....

 

Now there is some thought that the crater in Nicaragua might not be. I'm glad that I said "possibly" in my first post.

 

Scientists Doubt That Meteor Caused Crater In Nicaragua

 

http://knau.org/post/scientists-doubt-meteor-caused-crater-nicaragua

 

September 9, 2014

 

We reported on Monday that a meteor, thought possibly to be a chunk of an Earth-passing asteroid, was the cause of a 40-foot crater outside the international airport in the Nicaraguan capital.

 

But astronomers and NASA scientists are now casting doubt on that possibility. The biggest mystery is that no one so far has reported seeing a flash of light in the sky that would be expected to accompany such a meteor strike.

 

"While a meteoritic origin for this crater cannot be ruled out with absolute certainty, the information available at this time suggests that some other cause is responsible for its creation," NASA's blog concludes.

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Edited by monroe
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It's authenticity, however, will be real hard to prove, because any bean-sized quartz or metal droplet should be enough to cause a 12 m crater ...

 

[...]

 

What size crater should be expected for, say, a baseball ball hitting the dirt at the full speed 2014 RC's travelling at?

Surely way more than 12 m, in my opinion...

 

Try using the very convenient Computing Crater Size from Projectile Diameter online calculator :w00t: :

http://www.lpl.arizona.edu/tekton/crater_c.html

 

 

Thanks, jaclaz, you do rock! :yes

 

It seems I was off-scale by a factor of about 100!!! :ph34r:

 

Results for computing crater size from projectile diameter

Your Inputs: <<< a lump of pure iridium, the size of a baseball ball ... >>>

Projectile Descriptors

    Projectile Diameter     0.076     meters

    Projectile Density     22650     kg/m3

Impact Conditions

    Impact Velocity     50     km/sec

    Impact Angle     90     degrees

Target Descriptors

    Target Density     1000     kg/m3

    Acceleration of Gravity     9.8     m/sec2

    Target Type     loose sand

Results

The three scaling laws yield the following transient crater diameters (note that diameters are measured at the pre-impact surface. Rim-to-rim diameters are about 1.25 times larger!)

Yield Scaling     10.8    meters

Pi Scaling (Preferred method!)     9.2    meters

Gault Scaling     22    meters

Crater Formation Time     0.588    seconds

Using the Pi-scaled transient crater, the final crater is a Simple crater with a rim-to-rim diameter of  14.4   meters.

This impactor would strike the target with an energy of 6.51 x 10^9 Joules (1.55 x 10^-6 MegaTons).

A baseball ball made of iridium is required for a 14.4 m crater!!! Wow!!! :o

A pea-sized droplet of iridium should yield a crater of less than 3 m (or less than 2 m, if made of iron)...

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@monroe

Facts:

1) witnesses for loud boom (and possibly for burning smell)

2) no witnesses (yet) for flash of light in the sky

3) crater :yes:

4) no traces of meteorite found :no:

5) seismic trace of event recorded

 

Opinions:

1) "experts" quoted about meteorite "vaporized"

2) "astronomer" quoted attributing the meteorite to fragment of 2014RC

3) "seismologist" quoted saying that the seismic trace is compatible to an impact

4) "other experts" not convinced

 

http://en.wikipedia.org/wiki/Duck_test

 

Maybe if it sounds like a bomb and smells like a bomb, it could be a bomb?

 

@dencorso

I don't know. :unsure:

 

The 90 degrees simply don't sound "right", and I am not convinced about the speed.

 

Wouldn't a falling meteorite have a rather acute angle (something like 20° or less)?

 

Wouldn't *anything* falling through atmosphere tend to "stabilize" at a given "terminal velocity"?

http://en.wikipedia.org/wiki/Terminal_velocity

(or is the initial speed so high that it hits ground before being slowed down?)

 

In any case:

50*60*60=180,000 km/h 

180,000/1,225= Mach 146 ! :ph34r: that sounds like 5 times "re-entry speed"

http://en.wikipedia.org/wiki/Hypersonic_speed

 

What you can be rather sure is that "loose sand" weights much more than 1000 kg/mc, depending on mineral composition, anything between 1600 and 2200 kg/m3 would be more accurate.

 

jaclaz

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I think it might be around 30 degrees... but then I decided to go for it and try to shoot for maximums, even if somewhat unlikely, just to see what should be the maximum damage attributable to a baseball ball sized lump of the densest metal conceivable.

 

An interesting obsevation is that the "Pi Scaling (Preferred method!)" diverges for 60 degrees: there must be a bug in its programming (although that value can be estimated by interpolating, of course).

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