Asteroid at 27000 miles!

[Tweedledee]

This one is coming close next week...

http://bgr.com/2017/10/03/asteroid-flyby-tc4-near-miss-nasa/

[BAZ]

Strewth, yeah that's close, I'll get the tin foil hat ready.

[Smithysteve]

Blimey! Lets see what the media puts out...! ?

[stash]

I hear Michael Fish now works on Asteroid trajectory - hope you have your figures right . Do I have to give the pieces to anyone if it lands on my land ?

[Guest]

Any news yet about predicted magnitude, etc?

[Orion]

On 10/4/2017 at 09:02, Sunny Phil said:

Any news yet about predicted magnitude, etc?

I thought I read recently that it was quite a faint object >+20mag.  Spaceweather.com quotes an absolute magnitude of +28. I don't know what that means compared to the other magnitudes that appear in data tables.  Also, I know there will be refined predictions, but not seen any yet.  I would make an attempt to image it, but it would just be with my 300mm f5.6 zoom lens.  But I've only got down to ~ mag+13, which is not enough.  I might get fainter if I could get myself familiar with my new GT81, or, give my old 8.75" Fullerscope a shot, both on driven mounts.

[Tweedledee]

Most asteroids have a fairly low albedo, and even though it is coming pretty close, it is only 30 to 100 feet across, so is unlikely to reflect much light our way. If it is mag 20, then you might just see it with the 200" at Mount Palomar. I don't know, but would have thought that although a lot of data from a small scope may show a 20th magnitude star, it won't be possible to get much data on a moving object such as this.

 

I'm sure Spaceweather will use a magnitude of +28 to mean that it is beyond the visibility of just about any optics/imagers on the planet, and/or something that they don't know the brightness of.

 

The 8 metre Subaru telescope can reach mag +28 with a 10 hour image!

 

Hubble can reach +31.5 and the JWT +34. 

[Guest]

1 hour ago, Tweedledee said:

Most asteroids have a fairly low albedo, and even though it is coming pretty close, it is only 30 to 100 feet across, so is unlikely to reflect much light our way. If it is mag 20, then you might just see it with the 200" at Mount Palomar. I don't know, but would have thought that although a lot of data from a small scope may show a 20th magnitude star, it won't be possible to get much data on a moving object such as this.

 

I'm sure Spaceweather will use a magnitude of +28 to mean that it is beyond the visibility of just about any optics/imagers on the planet, and/or something that they don't know the brightness of.

 

The 8 metre Subaru telescope can reach mag +28 with a 10 hour image!

 

Hubble can reach +31.5 and the JWT +34. 

Haven't we got the technology to deflect it a bit so that it comes within visual range?

 

While we're at it, we could get them to chuck a few pebbles from the ISS and blast a few icebergs into Earth orbit.

[Smithysteve]

6 minutes ago, Sunny Phil said:

Haven't we got the technology to deflect it a bit so that it comes within visual range?

Do you mean naked eye ‘visual’ Phil?

It would no doubt be cloudy anyway 

[Tweedledee]

26 minutes ago, Sunny Phil said:

Haven't we got the technology to deflect it a bit so that it comes within visual range?

 

Not sure that idea would pass a health and safety risk assessment. 

[Guest]

55 minutes ago, Smithysteve said:

Do you mean naked eye ‘visual’ Phil?

It would no doubt be cloudy anyway 

Yes, I forgot about the cloud!

38 minutes ago, Tweedledee said:

Not sure that idea would pass a health and safety risk assessment. 

As long as the rocket is using eco-friendly fuel, they'd probably waive the other requirements, especially if it were made of at least 88% recycled metal.

[Orion]

Do you reckon the people on the ISS could see it visually? Or would the same issues apply and they would not see it without substantial optical equipment and long exposures?

[Tweedledee]

On the ISS they might be several hundred miles closer which will be of negligible help. They will be above the atmosphere which will give them several magnitudes of advantage. IMHO if they gain as much as 5 magnitudes and the 20th mag asteroid is effectively seen as a 15th mag asteroid, then it is still a very tough call, and will require equipment capable of imaging a moving object at 15th mag. I don't think they have that capability.

[Tweedledee]

Here's some latest info on how to see it. It will be 13th magnitude. 

http://earthsky.org/space/near-earth-asteroid-2012-tc4-close-pass-october-2017?mc_cid=61b093b767&mc_eid=98280cef03

[Orion]

2 hours ago, Tweedledee said:

On the ISS they might be several hundred miles closer which will be of negligible help. They will be above the atmosphere which will give them several magnitudes of advantage. IMHO if they gain as much as 5 magnitudes and the 20th mag asteroid is effectively seen as a 15th mag asteroid, then it is still a very tough call, and will require equipment capable of imaging a moving object at 15th mag. I don't think they have that capability.

Ask them on the ISS. Put it to them as a challenge.

[Smithysteve]

Happening tonight! Size of a house! quote from site;

 

On October 12th, 2017, around 05h 42min UT, a small piece of rock, which dimensions range from 10 to 30 m, will pass at approximately 51 200 km from Earth surface. Shining as a fast moving +12,8 magnitude point, it will be observable in most amateur instruments, providing they know where to observe!

https://www.imo.net/house-sized-asteroid-2012-tc4-coming-close-to-earth-tonight/