Large Asteroid passing Earth

[Paul M]

3 minutes ago, SilverAstro said:

Sky&Telescope agrees with Stellarium (but with funny American times ) :

http://www.skyandtelescope.com/observing/see-a-potentially-hazardous-asteroid-from-your-backyard/

(from which it will be noted that I was wrong, it does go into Boo, but only just, in one corner !!! not near 12Boo )

Which is pretty much in agreement with the track I got from SkySafari after selecting the correct elements from the two sets available, as shown in the second screen dump I posted earlier.

So hopefully, we're all in agreement with our tracks and the probability of us having 150% cloud cover on the night!   

[SilverAstro]

4 minutes ago, Paul M said:

 probability of us having 150% cloud cover on the night!   

I was about to post that the cloudGods must be pibeside themselves with LOLs, all this charting effort , dont we know what they now have in store for us ! the first ever recorded 2day monsoon in the UK !!

 

[Stu]

14 minutes ago, SilverAstro said:

Sky&Telescope agrees with Stellarium (but with funny American times ) :

http://www.skyandtelescope.com/observing/see-a-potentially-hazardous-asteroid-from-your-backyard/

(from which it will be noted that I was wrong, it does go into Boo, but only just, in one corner !!! not near 12Boo )

You lied!!  

Interestingly SkySafari has two entries for this asteroid, one of which seems accurate at least.

Note that the yellow line is the orbit not the motion across the sky.

To avoid any problems though I will rely on your charts  

[SilverAstro]

So, now we have sorted its where ,,,

how bright ? I found NASA-JPL saying "about mag11" , Guy found NASA-JPL saying 10pointsomething which I guess will be the max

How rapid will the rise to this be , and the fall away,   considering that we will miss the max  (by 12hr approx ?? each side  )

 

[Guy Wells]

Bare with me....

[Guy Wells]

[Ludd]

Getting excited about this, as I will be out in the Mojave desert on 17 to 19 April, by sheer coincidence!  Camera and astrotrac already packed. 

[SilverAstro]

21 minutes ago, Guy Wells said:

Thank you, very interesting.

Bit depressing for the night of 18>19   but good   better for 19>20, guess which will be the cloudy one !

[Davey-T]

Hoping for clear skies, just checked and the last asteroid I imaged was 2004-BL86 way back in October 2015.

Been waiting for a mod to edit the title of this topic, could be worse I suppose, could have put two Ss rather than two As 

Dave

[SilverAstro]

20 minutes ago, Davey-T said:

could be worse I suppose, could have put two Ss rather than two As 

or even an apostrophe or three 

 Asteroid's close approach ?

[Stu]

Sorted

[SilverAstro]

Guy's table is QI

I had assumed that max mag. would be at closest, which would be at max apparent speed across the sky, which would be at greatest hourly spacing on the Stellarium plot, which would be in Draco during daylight - and that the mag. varying  by distance to the sun would be small compared to the mag. variation due to its distance from us. ie. the mag. rise and fall would be approx. symmetric about  the point of closest.

It would seem, from that table, that one (or more! ) of those assumptions is wrong

Edit after a coffee : I may have forgotten phase - % illumination  ??? !

 

[Scooot]

For a bit of fun I went into orbit around the asteroid. Then pressed fast forward on the time function, hourly intervals and watched the earth and the moon race by. It gives some idea of the speed it's going  

[ericemms]

On 4/13/2017 at 21:30, SilverAstro said:

As I said earlier IF I have got Stellarium right ( I often get confused in it !) so it'd be a good idea if someone else could confirm my plots before the due date !! but they look good compared to those in the earthsky link for the Americas :

This is a continuous plot I get for its position every hour beginning at 20:00 BST 18 April, - the left red marker, through to the 21 April. Moving quickest through Draco but that is daylight here

Position as from London on Aug 19. Data on 2014 JO25 had to be uploaded to Stellarium through solar system editor.

[fireballxl5]

On 13/04/2017 at 22:15, Guy Wells said:

'13 32 10.15 +39 57 48.5  10.69 0.01361810556128  16.9515245 128.4810 /T  50.9156'

Thanks for the elements Guy. Do you know how these parameters relate to the data entry dialog for SkyMap Pro? - see attached.

Andy

[Guy Wells]

These are the orbital elements:

e.88541825389820834.8787e-07 

a2.0669746048693882.2562e-08au

q.23683755937399551.0081e-06au

i25.237823979097290.00010509deg

node30.656014348121293.9836e-05deg

peri49.541995073536320.00011219deg

M352.51215623602251.967e-05deg

tp2457823.076437449078
(2017-Mar-10.57643745)5.9478e-05JED

period1085.428293892536
2.971.7772e-05
4.866e-08d
yr

n.33166631275934125.4304e-09deg/d

Q3.897111650364784.2539e-08au

[Vega]

Cometwatch have an article about it with detailed findercharts... http://www.cometwatch.co.uk/650m-asteroid-2014-jo25-close-approach-to-earth/

[BellP]

Hi,

What would be the smallest telescope and/or bins to view this please, would 10x50s be a stretch? I live very near to the Royal Observatory Greenwich and thought they might have an eye out for this but there is no mention on their website.

Peter

[Dave In Vermont]

I've read a rather 'mainstream' news story that it could be spotted with a 3" telescope. The magnitude should tell us what to use - and the dedication of the obverver.

Best of luck to all trying,

Dave

[BellP]

Thanks, yes I read similar, we shall see(or, maybe not)...

Peter

[John]

45 minutes ago, BellP said:

Hi,

What would be the smallest telescope and/or bins to view this please, would 10x50s be a stretch? I live very near to the Royal Observatory Greenwich and thought they might have an eye out for this but there is no mention on their website.

Peter

It the brightness predictions are correct then the maximum brightness will be magnitude 10.7 (or therabouts). I would find that very tough from my back garden with a 50mm aperture but I guess it could be done from a very dark site

 

[BellP]

Thanks for the info. I suppose I was clutching at straws really.

Tony Hancock - comedy legend!!

Peter