Near Earth Asteroid 5/3/2016

[johnnyt123 (John)]

Hi all.

I just heard on the morning show that an asteroid 30km across will be passing within 18000km of earth.
so close that is may be visible to the naked eye.

Just wondering if anyone has any information as to whether we will be able to see it from Australia and what time it will be passing.
Does anyone know of any websites that describe the trajectory?

regards

Johnny

[Kunama]

Hi Johnny, 2013 TX68 is now predicted to pass on the 8th of March and the likelihood of being seen visually is diminished as the latest prediction puts the pass much further away at 5 million kilometers than the original 24,000.


Lots of info on NASA website or goggle up 2013 TX68

[johnnyt123 (John)]

so initial estimates are quite a bit off....

[astroron (Ron)]

Originally Posted by johnnyt123

Hi all.

I just heard on the morning show that an asteroid 30km across will be passing within 18000km of earth.
so close that is may be visible to the naked eye.

Just wondering if anyone has any information as to whether we will be able to see it from Australia and what time it will be passing.
Does anyone know of any websites that describe the trajectory?

regards

Johnny

Here is some information.
No where near 30kms across
https://en.wikipedia.org/wiki/2013_TX68
Cheers

[Allan_L (Allan)]

This sounds like the source of the story

Originally Posted by BGR.com

30-meter wide asteroid will be passing Earth so close early next month that we might be able to see it in the sky, NASA has announced. And it might even hit Earth at some point in 2017.

2013 TX68 will either pass as close as 18,000km (11,000 miles) of Earth, or about 14 million kilometers (9 million miles) on March 5th. The asteroid approached Earth mostly during the daytime, which made monitoring it rather difficult. This is why we have no idea how close it’s going to be.

“This asteroid’s orbit is quite uncertain, and it will be hard to predict where to look for it,” NASA Centre for Near Earth Object Studies manager Paul Chodas said. “There is a chance that the asteroid will be picked up by our asteroid search telescopes when it safely flies past us next month, providing us with data to more precisely define its orbit around the Sun.”

The object will not hit Earth this year, but there is a 1 in 250 million chance it’ll come crashing down to Earth in 2017.

[deanm (Dean)]

"The asteroid approached Earth mostly during the daytime".

At first I snorted (did TX68 go to bed at nightfall?!).

Then I realised that what was meant (but not said) is that the thing is pretty small/low albedo & only visible at most recent closest approach.

And closest (i.e. visible) approach was on the sun-lit hemisphere of Earth.

Or am I talking out of my hat?!

Dean

[pdthomas23 (Peter)]

Hello All,

Back in Sep/Oct 2013, 2013 TX68 was passing Earth's orbit on its way in to perihelion. It passed "under" the Earth and would still have been visible for southern observers up until Oct 12 and 13 but no-one caught it after Magdalena Ridge last saw it on Oct 9. The asteroid was then at low solar elongation and un observable. It passed back out again in Jan 2014 but was only mag 27 and then spent 2014 and 2015 travelling out to aphelion and back. When it crossed back in again in Dec 2015 it was still only mag 27. Now 2013 TX68 is heading back out again but this time both Earth and the asteroid will be near the crossing point at the same time.
The orbits don't precisely cross. 2013 TX68 passes up through Earth's orbital plane a bit before it crosses Earth's path within that plane. The uncertainty region is a long thin tube about 20 million km long but only about 200 km across stretched out along its orbit. The closest perpendicular distance from Earth to the uncertainty tube is about 20,000 km but since the tube is only 200 km across there is absolutely zero chance of impact. A close approach of 20,000 km would only occur if 2013 TX68 passes the crossing point on March 5 at the same time as the Earth is there. If it passes earlier or later the distance will be much greater.
When the JPL NEO office put out its original press release on Feb 2 the nominal time was on March 5 and the nominal distance was 1.3 lunar distances. The addition of the 4 PAN-STARRS observations from 2013-09-29 and 2013-10-04 that were reported on Feb 11 has shifted the uncertainty envelope back in time so that now the nominal pass is on March 8 at 13 lunar distances. The 1-sigma uncertainty is still 2 days so the pass could happen anywhere from March 2 to March 14 (out to 3 sigma) and thus a really close pass on March 5 is still possible, although unlikely.

Peter Thomas
Oakleigh

[xelasnave]

Will it hit us?
No.
Lets speculate as to the destruction if indeed it slammed into us.
It would be all over, the end I expect.
It would be back to bacteria for life on what be left after dust settles, the shock waves stop etc

[pdthomas23 (Peter)]

Alex,

2013 TX68 is only about 30 meters across, not 30 km.
A bang like Chelyabinsk, only a bit bigger.

Peter Thomas
Oakleigh

[xelasnave]

Thanks thats no fun.
But if it was 30 klms can we talk about that.
They can be 30 klms and they could hit the Earth.
Imagine it.

[deanm (Dean)]

Read all about it! https://en.wikipedia.org/wiki/Impact_event

Depending on density, trajectory, velocity etc (i.e. energy released), it seems that once the impactor is more than 5-10 km in diameter, everything alive on Earth starts to have A Very Bad Day.

Diameter >100 km & that's it, folks....!

Dean