Asteroid 2004 BL86

[AstroJunk (Jonathan)]

And any SE Qld observers using the MPC Ephemeris service (http://www.minorplanetcenter.net/iau/MPEph/MPEph.html) for precise coordinates, you can take a shortcut and use my observatory code - Q79 rather than enter lat/long/alt and the results will get you pretty close!

It will be moving reasonably quickly at closest approach, so get positions with a 10 minute interval over the period you are hoping to see it then point your scope in that direction ahead of time and look for the asteroid moving through the field of view. Once you get the hang of it, its easy to find them

[pdthomas23 (Peter)]

Originally Posted by astroron

This data from MPC bears no resemblance to your data.
Putting the data into the sky program has it no where near
the positions on your program.
What am I doing wrong.
Note the position for the 26 Jan?
Orbital elements:
2004 BL86 PHA 0.004A
Epoch 2004 Jan. 16.0 TT = JDT 2453020.5 MPC
M 24.06569 (2000.0) P Q
n 0.53764402 Peri. 309.77739 +0.17125920 -0.92924834
a 1.4978656 Node 127.19921 +0.98185576 +0.13351605
e 0.4043040 Incl. 24.26670 +0.08142210 +0.34448656
P 1.83 H 18.8 G 0.15
From 10 observations 2004 Jan. 30-31.

Ephemeris:
2004 BL86 a,e,i = 1.50, 0.40, 24 q = 0.8923
Date TT R. A. (2000) Decl. Delta r Elong. Phase V
2004 01 26 14 13.36 +09 38.5 0.334 1.078 97.2 64.9 18.9
2004 02 05 14 28.98 +20 32.5 0.363 1.137 105.3 56.7 18.9
2004 02 15 14 37.32 +29 52.5 0.400 1.198 112.4 49.7 19.1
2004 02 25 14 37.37 +37 33.8 0.444 1.260 117.9 43.9 19.2
2004 03 06 14 28.82 +43 27.6 0.495 1.322 121.9 39.6 19.4
2004 03 16 14 12.74 +47 26.9 0.553 1.383 124.1 36.5 19.7
2004 03 26 13 51.89 +49 28.8 0.619 1.443 124.7 34.7 20.0
2004 04 05 13 30.60 +49 41.3 0.693 1.500 123.7 33.7 20.3
2004 04 15 13 12.62 +48 25.0 0.775 1.556 121.6 33.3 20.6
2004 04 25 12 59.90 +46 04.5 0.864 1.609 118.6 33.3 20.9
2004 05 05 12 52.76 +43 02.9 0.960 1.660 114.9 33.4 21.2
2004 05 15 12 50.46 +39 38.3 1.063 1.708 110.9 33.6 21.5
2004 05 25 12 52.08 +36 02.3 1.172 1.753 106.5 33.6 21.8
2004 06 04 12 56.78 +32 23.0 1.286 1.796 102.0 33.5 22.0

Ron, what you have there is the original discovery MPEC 2004-B80 (http://www.minorplanetcenter.net/mpec/K04/K04B80.html) and geocentric ephemeris from 31 Jan 2004.

The current elements (at a reference epoch) for (357439) 2004 BL86 can be found buried in the elements downloads for various software packages.
http://minorplanetcenter.net/iau/Eph...ftwareEls.html
specifically in the collection "Observable unusual minor planets (including NEOs)"
Here's an example from the collection for StarryNight
http://www.minorplanetcenter.net/iau...t07Unusual.txt
357439 2004 BL86 18.9 1.502231 0.403058 23.7437 126.7219 311.2479 246.9747 2456800.5

It is not immediately obvious to the untrained eye but the objects are sorted according to their "packed designation" (part of an 80-column data format defined by the MPC). In this case the packed designation is 'Z7439' (and the case of the Z is important. The 'Z' stands for '35' and is a way of packing a 6-digit numeral into the allotted 5 spaces for the number.
Usually software is set up to pull the correct file format from the MPC so just updating gets the most recent data. However, there is still the issue of propagating the position from the reference epoch to the observing epoch and for close passes this can require more complex computing than is usually sufficient.
You can also use the Minor Planet Ephemeris Service to plot a set of topocentric positions for a specified latitude, longitude and altitude at specified times.
http://www.minorplanetcenter.net/iau/MPEph/MPEph.html
This is a fully perturbed solution and so the astrometric (J2000) RA and Dec should be spot on.
You can get similar output from the JPL HORIZONS system
http://ssd.jpl.nasa.gov/horizons.cgi

Peter Thomas
Oakleigh

[pdthomas23 (Peter)]

Originally Posted by AstroJunk

And any SE Qld observers using the MPC Ephemeris service (http://www.minorplanetcenter.net/iau/MPEph/MPEph.html) for precise coordinates, you can take a shortcut and use my observatory code - Q79 rather than enter lat/long/alt and the results will get you pretty close!

It will be moving reasonably quickly at closest approach, so get positions with a 10 minute interval over the period you are hoping to see it then point your scope in that direction ahead of time and look for the asteroid moving through the field of view. Once you get the hang of it, its easy to find them

Here's the result from the Minor Planet Ephemeris Service using Jonathon's Q79 station, at 10 minutes intervals from 1000 UT (=2000 AEST = 2100 AEDT).

(357439) 2004 BL86
Display all designations for this object / # of variant orbits available = 3
Epoch 2014 Dec. 9.0 TT = JDT 2457000.5 (M-h) MPC
M 354.03306 (2000.0) P Q
n 0.53531751 Peri. 311.25498 +0.15732606 -0.93331881 T = 2457011.64655 JDT
a 1.5022023 Node 126.72037 +0.98285078 +0.11614661 q = 0.8967044
e 0.4030735 Incl. 23.74363 +0.09619180 +0.33974396 Earth MOID = 0.00817 AU
P 1.84 H 19.0 G 0.15 U 1
From 83 observations at 7 oppositions, 2004-2014, mean residual 0".51.
Last observed on 2014 Dec. 29.
Perturbed ephemeris below based on elements from MPO 321822.


Discovery date : 2004 01 30
Discovery site : Socorro
Discoverer(s) : LINEAR
Z7439 [H=19.0] Date UT R.A. (J2000) Decl. Delta r El. Ph. V Sky Motion Object Sun Moon Uncertainty info h m s "/min P.A. Azi. Alt. Alt. Phase Dist. Alt.
2015 01 26 100000 07 48 59.8 -26 27 47 0.0083 0.990 133.5 46.2 10.3 147.07 016.6 101 +47 -16 0.41 096 +34
2015 01 26 101000 07 49 31.0 -26 04 14 0.0083 0.990 133.9 45.7 10.3 147.75 016.5 099 +49 -18 0.42 096 +32
2015 01 26 102000 07 50 02.0 -25 40 33 0.0083 0.990 134.3 45.3 10.3 148.41 016.4 098 +51 -20 0.42 096 +30
2015 01 26 103000 07 50 32.8 -25 16 46 0.0083 0.990 134.7 44.9 10.3 149.07 016.3 097 +53 -21 0.42 096 +29
2015 01 26 104000 07 51 03.5 -24 52 51 0.0083 0.990 135.1 44.5 10.3 149.71 016.1 095 +55 -23 0.42 096 +27
2015 01 26 105000 07 51 34.0 -24 28 50 0.0082 0.991 135.6 44.1 10.3 150.35 016.0 094 +57 -25 0.42 096 +25
2015 01 26 110000 07 52 04.4 -24 04 41 0.0082 0.991 136.0 43.7 10.2 150.97 016.0 092 +59 -27 0.42 096 +23
2015 01 26 111000 07 52 34.6 -23 40 26 0.0082 0.991 136.4 43.3 10.2 151.59 015.9 090 +61 -28 0.42 096 +21
2015 01 26 112000 07 53 04.7 -23 16 05 0.0082 0.991 136.8 42.9 10.2 152.19 015.8 088 +63 -30 0.42 096 +19
2015 01 26 113000 07 53 34.6 -22 51 37 0.0082 0.991 137.2 42.4 10.2 152.77 015.7 086 +65 -31 0.42 096 +17
2015 01 26 114000 07 54 04.4 -22 27 03 0.0082 0.991 137.7 42.0 10.2 153.35 015.6 084 +67 -33 0.42 096 +15
2015 01 26 115000 07 54 34.1 -22 02 23 0.0082 0.991 138.1 41.6 10.2 153.91 015.5 081 +69 -34 0.42 096 +13
2015 01 26 120000 07 55 03.6 -21 37 37 0.0081 0.991 138.5 41.2 10.1 154.45 015.4 078 +71 -36 0.42 096 +11
2015 01 26 121000 07 55 33.1 -21 12 46 0.0081 0.991 139.0 40.7 10.1 154.98 015.4 074 +72 -37 0.42 096 +09
2015 01 26 122000 07 56 02.4 -20 47 49 0.0081 0.991 139.4 40.3 10.1 155.49 015.3 069 +74 -38 0.43 096 +06
2015 01 26 123000 07 56 31.6 -20 22 46 0.0081 0.991 139.8 39.9 10.1 155.99 015.2 064 +76 -39 0.43 096 +04
2015 01 26 124000 07 57 00.7 -19 57 38 0.0081 0.991 140.3 39.4 10.1 156.47 015.2 056 +78 -40 0.43 096 +02
2015 01 26 125000 07 57 29.7 -19 32 26 0.0081 0.991 140.7 39.0 10.1 156.93 015.1 047 +79 -41 0.43 096 +00
2015 01 26 130000 07 57 58.6 -19 07 08 0.0081 0.991 141.1 38.6 10.1 157.38 015.1 036 +80 -42 0.43 096 -02
2015 01 26 131000 07 58 27.4 -18 41 46 0.0081 0.991 141.6 38.1 10.0 157.81 015.0 023 +81 -42 0.43 096 -04
2015 01 26 132000 07 58 56.1 -18 16 20 0.0081 0.991 142.0 37.7 10.0 158.22 015.0 008 +81 -43 0.43 096 -06
2015 01 26 133000 07 59 24.7 -17 50 49 0.0080 0.991 142.4 37.3 10.0 158.60 014.9 354 +81 -43 0.43 096 -08
2015 01 26 134000 07 59 53.3 -17 25 15 0.0080 0.991 142.9 36.8 10.0 158.97 014.9 341 +80 -44 0.43 096 -11
2015 01 26 135000 08 00 21.8 -16 59 37 0.0080 0.991 143.3 36.4 10.0 159.32 014.8 331 +78 -44 0.43 096 -13
2015 01 26 140000 08 00 50.2 -16 33 55 0.0080 0.991 143.8 36.0 10.0 159.65 014.8 323 +77 -44 0.43 096 -15

Peter Thomas
Oakleigh

[OzEclipse (Joe Cali)]

Originally Posted by astroron

I have been through the MPC link above and trolled through all their planetarium sites and cannot find a listing for 2004BL86.
Cheers
PS I use the site all the time to down load my comet update's so am no stranger to it.

Ron,
click on OBSERVERS
Then Ephemeris
Search on 2004 BL86 (put the space between 2004 and BL86

Joe

[Dennis]

Just a cautionary note for those who plan to use a planetarium programme to find 2004 BL86.

On one of my previous searches for another NEO, I compared the data from:

• The Sky 6
• Starry Night Pro Plus 6
• SkyTools 3 Pro

And lo and behold, they were all slightly different.

The difference was sufficient that not all of them would have placed the NEO on my CCD chip (approx. 22x18 arc min). All had the same Time/Lat/Long settings and obtained their (fresh) input from their respective web servers.

I forget which was the most accurate now, but I do recall that the Horizons JPL data were spot on.

Cheers

Dennis

[OzEclipse (Joe Cali)]

I ran a comparison of topocentric ephemerides for Brisbane Sydney Canberra Melbourne and Adelaide.

Brisbane Sydney, Melbourne and Adelaide differ by no more than 1/20th of a degree from Canberra. This asteroid is much further away than the asteroid we had parallax problems with last year. Sorry for the false alarm. Perth is up to 10 minutes (1/6th of a degree) different but still within the field of a wide field eyepiece.

The attached finder charts - plotted for Canberra onto Toshimi Taki's Mag 6 and Mag 8.5 sky atlases can therefore be used for Brisbane Sydney, Melbourne and Adelaide. I've used Canberra because it is closest to the middle of the other cities. If you use a chart of coords for Brisbane, for Melbourne or Adeaide, differences will be bigger.

Bigger versions of the charts can be found at http://joe-cali.com/astronomy/dowloads/BL86

Lots of easy bright navigation stars for beginners to star hop. If you have a GOTO mount, generate your own navigation coordinates for your site.

http://www.minorplanetcenter.net

click on OBSERVERS
Then Ephemeris
Search on 2004 BL86 (put the space between 2004 and BL86

DATE format is YYYYMMDD

cheers

Joe

[astroron (Ron)]

Originally Posted by Dennis

Hi Ron

The MPC data you have copied/pasted looks like it shows the positional information in the date range of 2004 01 26 to 2004 06 04.

The Sky X Pro and Sky Safari data is for 2014 Jan 26th, some 10 years later.

Or, am I missing something?

Cheers

Dennis

Thanks Dennis and all.
Cheers

[Suzy]

Thank you so much Joe!
And everyone else too - there's just such a ton of helpful information on here. I've linked this thread to this morning's fb post on the asteroid, so hopefully it'll help lots more people who are looking for guidance .

I'm looking forward to this, this will be my first time of tracking an asteroid. Well, aside from Ceres and Vesta anyhow . Looks like I might have some clear skies finally .

An easy guide with finder charts by astroblogger, Ian Musgrave, just updated this morning: http://astroblogger.blogspot.com.au/...-neo-2004.html

[AstroJunk (Jonathan)]

http://youtu.be/EvAMlbNVWA4

Here it is from last night. Not an easy object to locate due to the rich star field, but the Minor Planet Center positions are spot on.

Fingers crossed the sky stays clear, it will be 2 mags brighter and twice as fast tonight.

[pdthomas23 (Peter)]

Nice video Jonathan.
A bit of haze coming in at the end?
Did you try any video as it entered the LMC?

Peter Thomas
Oakleigh

[AstroJunk (Jonathan)]

Originally Posted by pdthomas23

Nice video Jonathan.
A bit of haze coming in at the end?
Did you try any video as it entered the LMC?

Peter Thomas
Oakleigh

Thanks. Bit of high cloud rolling through. It was my first clear night for a long while - I didn't get much opportunity to record anything else before the clouds rolled back over to spoil my fun...

It was mainly a dry run before helping out with the Slooh live feed in a couple of days time.

[Suzy]

That was super, I really enjoyed your video Jonathan, thank you.
I'm wishing myself lots of luck as I try to track this, seeing my first near Earth astreroid tomorrow with my 10" dob. Oh what an exciting Australia Day finale!

[AstroJunk (Jonathan)]

Have a look at tonight's version Suzy - Much easier to spot!

http://youtu.be/IPCj0EAyOCM

[Suzy]

Oh wow, NICE ! thank you, Jonathan. I'm really looking forward to tomorrow night and you've instilled more excitement within me with your awesome videos, thank you so much.

[icytailmark (Mark)]

is it still visable or am i too late?

[OffGrid (Steve)]

G'day Mark,

It is not too late. The big event is on tonight.
However, it is not looking good here on the Central Coast as it is cloudy with showers.
Beginning to look like the only view Debbie and I get will be Johnathon's remarkable video clips as posted.

Aside from that, a special thank you to all who have shared and posted significant contributions on how, when and where Asteroid 2004 BL86 may be viewed.

From a humble newbie, love this IIS Community

Steve

[Rob_K]

Here's my test from last night using topocentric JPL ephemeris. Tried 10, 15 & 30 sec subs. 30 were too long, giving streaks. 10 sec had very weak signal. Might try 10 sec tonight though, given it will be faster and much brighter.

Cheers -

[qarocks (Steve)]

How would a total noob with a telescope go about finding this, on the east coast?

[Rob_K]

Originally Posted by qarocks

How would a total noob with a telescope go about finding this, on the east coast?

Not an easy target. That said, if you don't push the limits you'll never learn anything - we all have failures and disappointments but the rewards of an occasional success can outweigh all that! Worth a shot whatever.

First up, depends a lot on your telescope and your familiarity with it - if you're working with a super-duper go-to scope that's well-aligned on the night you can punch in the co-ordinates for a certain time, let the scope slew to the field and look for the moving star! If you're using a push-to job like most of us it gets a little more difficult. Again you need to determine a field for a certain time. Then locate the field at that time and look for a moving star.

To find where the asteroid should be at a certain time at your location you need to get hold of an ephemeris (list of co-ordinates of an object over time). There were links posted earlier for these, and remember you have to generate one for your location. Then you could use a planetarium program like Stellarium (free) or Starry Night (not free) to generate a view of where it is in the sky and by zooming in, a view of what the starfield should look like viewed through your telescope.

If you're not familiar with all this stuff, as an alternative I could put up a series of charts for you, based on a position for the asteroid at, say, 11pm tonight from your location, only if you could provide a slightly better location (town for instance, don't want to know your address & bank account details LOL!). Your telescope type (reflector etc), size (aperture, focal length) and eyepiece you're likely to be using (15mm, 20mm, 30mm...) would help in generating an eyepiece view for you.

Good luck whatever!

Cheers -

[qarocks (Steve)]

Cheers for that.

My location is Ringwood, Melbourne, Victoria.

I have a Skywatcher ED80 - 600mm and has a 28mm EP.

From an earlier chart I saw I have a rough idea, but the chances of me lining it up and finding it are almost 0.

I have a goto mount, but still tinkering with aligning it correctly.