Asteroid 2004 BL86

[OffGrid]

G'day folks,
Just joined this forum and would appreciate any useful info for viewing Asteroid 2004 BL86 that is supposedly due for a scope visible flyby around 26-27 Jan this year.
1st heard about it from son in law to be and confirmed through Earthsky.org.

Seems it will be in Cancer just after dark but wondering how long viewable as Cancer is vey low in the east at that time.

Steve

[Dennis]

Here is a screen capture from The Sky X Pro showing the position and details for Brisbane on 26th Jan 2014 at 23:25.

Rises: 16:45
Transits: 23:29 at an altitude of 80º
Cheers

Dennis

[OzEclipse]

Are you sure that Sky X calculates topocentric rather than geocentric coordinates? Makes a huge difference to the position for a NEO.

At its brightest, before dawn on Jan 27, the objects apparent position in the sky differs by some 2 degrees between Brisbane and Melbourne. It may only just be visible in 7x50 binoculars at its brightest to a keen experienced observer.

It will be visible over several nights but brightest on Jan 26. That night, it will move at approximately 1 degree per hour or to put it another way, through the diameter of the Moon ~ every 30 minutes. Its motion is perpendicular to the motion of the background stars.
Best policy is to generate coordinates for your specific location using the ephemeris service at :
http://www.minorplanetcenter.net

cheers
Joe

[Dennis]

Hi Joe

I have been lucky enough to capture a few of these NEO’s from my back garden in Brisbane using The Sky X Pro (and previously The Sky 6 Pro).

I usually refresh the orbital elements from within The Sky via the SB website on the day I plan to capture the event. I understand that the positional calculations for the “Find” and “GoTo” operations are based on my saved/selected Location (Lat & Long entered using GPS).

So far The Sky has managed to place the object on the chip (FOV approx. 25x18 arc min) as predicted by the on-screen representation.:thumbsup:

Here are a few examples when I have been lucky enough with the somewhat fickle SE Qld weather…:rolleyes:

Cheers

Dennis

[OzEclipse]

Dennis
Great. You're obviously on top of it. I'm not familiar with Sky X and so my question / caution was only of a general nature.

Some of these programs don't do topocentric calcs.

For example, different programs when plotting the path of 2012 DA 14 in early 2013 which was a closer approach gave 10 degree variations in apparent position.

Cheers

Joe

[Blue Skies]

Thanks for the reminder that I needed to input my location (be topocentric!).

I've used the JPL HORIZONS (http://ssd.jpl.nasa.gov/horizons.cgi) web interface to generate an ephemeris for myself for this event. The night of the 26th is indeed looking to be the best night.

I think I used a different online source for 2012 DA14 but can't remember exactly where to find it.

[pdthomas23]

Hello All,

Here are some charts I made in Cartes du Ciel for seeing 2004 BL86 from my location in suburban Melbourne.
I used a topocentric ephemeris from JPL's HORIZONS system as of about a week ago.
http://ssd.jpl.nasa.gov/?horizons
It included the recent observations from the iTelescope (Q62) but not those from the LCOGT (W87) in the last few days. Uncertainty was down to only about 30 arc-seconds so shouldn't be too bad. However there will be a parallax difference for other locations.
For those using Cartes du Ciel there is a How-To for close asteroid passes that was written for the pass of 2012 DA14 in 2013.
http://www.ap-i.net/skychart/en/documentation/display_of_neos
2004 BL86 is 3 lunar distances (1.2 million km) so nowhere near as close, much more like (4179) Toutatis in 2004 or 2006 VV2 in 2007.
If you just use CdC's regular asteroid display it will be off by about 1 degree. It just takes the Keplerian elements at a reference epoch from the Minor Planet Center and propagates them to the observation epoch using 2-body methods.
The asteroid will be around mag 10 during the night of 26-27 Jan and will be visible the whole night.

[Edit]
Forgot to say that the asteroid is marked with open diamonds on my charts.
The 10 pm (AEDT) field is near Ksi Puppis and M93.

Peter Thomas
Oakleigh

[Dennis]

Hi Joe

These are excellent and very relevant points you raise and are real traps for the unwary with these close fly-by NEOs.:)

In The Sky X Pro “Object Information Report” Panel both Topocentric and J2000 values for RA and Dec are provided. You can see these in the left hand text panel of the screen capture that I posted, although it might take some digging out as it is a busy graphic!:)

The only times I have noted large discrepancies are when I download the orbital elements several weeks before a scheduled NEO fly-by and I then forget to update or refresh them on the day.:rolleyes:

Thank goodness for Wi-Fi and Internet Servers making this data accessible from my back garden at all hours of the late night or early morning!:thumbsup:

Hopefully the OP Steve (OffGrid) will find these discussions helpful and contribute to a successful observation of this close fly-by.

Cheers

Dennis

[OffGrid]

Cheers Dennis, Joe and Peter,

Being a newbi the info provided will be challenging to decipher, although probly first language for the regulars like yourselves.

I will take your responses up to the pony club at Mangrove Mountain tonight and ask the team to help me with the data.

Much appreciated.

Steve

[OzEclipse]

Steve,

You possibly saw an American article. It won't be in Cancer until much later - around midday on the 27th our time. The Cancer just after dark reference must be relating to the USA. We'll see it in the constellations of Hydra and Puppis during the night of the 26th. It travels from just north of M48 in Puppis towards M93 in Hydra during our dark hours.

Topocentric coordinates are the position of the asteroid against background stars as seen from your position on the Earths surface.

Geocentric coordinates are are the position of the asteroid against background stars as seen from the centre of the Earth.

For distant asteroids like those in the asteroid belts between Mars and Jupiter, there is no practical difference. For Near Earth Objects (NEO's) parallax error causes differences in the apparent position even between cities along the east coast.

The attached diagram illustrates the effect. Position C is the centre of the Earth (Geocentric) Pos A and D show very different apparent positions because of their different locations. Pos B lies on the geocentric line and experiences no parallax shift from the geocentric position but only for an instant. During the night, the Earth's rotation moves it off this line and the position once again experiences parallax shift.

DA14 was very close to Earth so this difference was particularly large. This asteroid is a little further out so that differences along the coast are not so extreme.

Hope this clears it up a little.

Joe

[pdthomas23]

Actually Joe has mixed up his Messier references.
The asteroid starts the night near Ksi Puppis and M93 and finishes near M48 in Hydra in the morning.

Peter Thomas
Oakleigh

[Dennis]

I used The Sky X Pro to draw the path of 2014 BL86 as viewed from our back garden in Brisbane (note Joe’s post re parallax and need for Topocentric coordinates for other locations).

The plot stars at 7:00PM AEST and is labelled every 1 hour, ending at 12:00pm (midnight) by which time is has already transited the Meridian.

Cheers

Dennis

[julianh72]

According to this report http://www.jpl.nasa.gov/news/news.php?feature=4441 , 2004 BL86 is expected to be observable to amateur astronomers with small telescopes and strong binoculars.

Is this asteroid in the SkySafari catalog? I haven't been able to find it using the catalog search facility, so I'm wondering whether it has another designation? I would LOVE to be able to catch a look in my telescope or 15x70 binoculars, if only I knew where to look!

[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.

[Dennis]

Hi Julian

I have Sky Safari Pro 4 running on my iPad and just updated the minor bodies list (Settings - Solar System - Update Minor Bodies) and I was able to find and centre 2004 BL86 via the Search screen.

Not sure if you have the Pro version? If so, be sure to update your minor bodies.

Cheers

Dennis

[Dennis]

Hi Ron

I clicked the link and it took me to the MPC website.

At top right of the Home Page in "Search MPC" I typed 2004 BL86 and it found the object and displayed a page full of data.

I had a space between 2004 and BL86.

Cheers

Dennis

[julianh72]

Thanks!

I'm running SkySafari 4.3.5 Plus. I updated the Minor Bodies database, but it doesn't recognise "2004 BL86" as an object name. However, I was able to find it using its other designation "357439". http://en.wikipedia.org/wiki/%28357439%29_2004_BL86

Best time to view looks to be about 9:00 pm - 2:00 am (Brisbane time) on the night of Sunday 26 / Monday 27 January, when it should reach magnitude 9 - 10 (so probably going to need a telescope rather than binoculars to spot it), in the general vicinity of Sirius.

[Dennis]

That’s odd – I did a search for "2004 BL86" via the Search screen and it recognised and found the NEO object okay – see attached screen capture.

I have also included the Object Info and Sky Display screen captures showing 2004 BL86.

Cheers

Dennis

[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.:question:
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

[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

[AstroJunk]

And any SE Qld observers using the MPC Ephemeris service (http://www.minorplanetcenter.net/iau/MPEph/MPEph.html (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]

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/Ephemerides/SoftwareEls.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/Ephemerides/Unusual/Soft07Unusual.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]

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 (http://cgi.minorplanetcenter.net/cgi-bin/pdes.cgi?pm=Z7439) / # 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]

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.:shrug:

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.:thumbsup:

Cheers

Dennis

[OzEclipse]

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]

Thanks Dennis and all. :thanx:
Cheers:thumbsup:

[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 :prey:.

An easy guide with finder charts by astroblogger, Ian Musgrave, just updated this morning: http://astroblogger.blogspot.com.au/2015/01/update-seeing-close-flyby-of-neo-2004.html

[AstroJunk]

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]

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]

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]

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. :D

[icytailmark]

is it still visable or am i too late?

[OffGrid]

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]

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

[Rob_K]

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. :thumbsup:

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!). :P 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]

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.

[qarocks]

Looking at a rough chart, and i'm guessing that if I look at the star G-Hya around 11pm it might be close?

[pdthomas23]

No, that's way off.
At about 10 pm it will be near Ksi Pup.
At about 5 am it will pass through M48.
Connect the dots in between.

I've attached a chart for the whole night and for 10 pm

[Edit]
Apologies for consuming bandwidth. The two attached charts, along with some others can also been seen in my post from Jan 16 which is post #7 in this topic

Peter Thomas
Oakleigh

[Rob_K]

Here's a guide - with the eyepiece view, the asteroid will be similar in brightness to the faintest stars shown. You've probably got an inverted view but I've included the corrected view in case you use an erecting prism.

The red circles are the approximate field of view using the 28mm eyepiece but not exactly. It's similar magnification to my scope with a 40mm eyepiece so I used that field size.

Hope that helps, and that you can see enough stars in the sky to work out the rough position of the asteroid in order to aim your telescope in the first place! Good luck. :thumbsup:

Cheers -

[Suzy]

That's a very helpful guide, thank you Rob.
I was beginning to wonder what my chances were of catching it (my first time), but this has given me some confidence.
But now I'm fully clouded out here in Brisbane and I don't like my chances.:sadeyes:

[JohnG]

Been clear here all day until just before sunset....:(, managed this quick 120 second shot at 1019 UTC before the clouds came completely in.

Cropped from a single Luminance, clouds have stayed put unfortunately...

[Suzy]

Wonderful capture John, and so lucky for you that you were able to grab what you did. :)

I'm still clouded out here in Brisbane grrrrr :mad2:.

I just came across this terrific video tutorial via Spaceweather.com on how to find it. It's a goody :D .
https://www.youtube.com/watch?v=l59RNNhVlKo

[pdthomas23]

Sorry to make you all jealous but we've got pretty clear skies here in Melbourne. I've been following it visually for the last hour. Picked it up around 10 pm. Don't have any photographic equipment with the capability to do the job however, so you'll just have to take my word for it.

Peter Thomas
Oakleigh

[AstroJunk]

LOL Peter, Thanks!

Completely clouded out as expected in Brisbane - enjoy your views :thumbsup:

[Rob_K]

Here's a couple from tonight, two different stacks of the same subs. These were 10-sec exposures which was a bit too long shooting with a 200mm lens as the asteroid trailed (not so visible in these as the size is considerably reduced). I have 7-sec subs I haven't processed yet. Beautiful night here.

Cheers -

[cometcatcher]

Nice shots Rob!

[inline_online]

Lovely clear skies from Perth. Just right for hunting NEAs.

Tried and failed. Unfortunately I couldn't even find my reference stars due to light pollution. I star-hopped frantically for 25min but by the time I thought I was in the right area it had moved on.
Looking forward to the next one.

[Dennis]

The weather forecast for Brisbane for closest approach on Monday 26th Jan looked dismal, so I set up in variable conditions on Sunday and managed to grab 8 x 60 sec frames with the Tak Mewlon 180, Tak X0.8 reducer (1728mm at F9.6) and ST2000XM before the clouds rolled in.:).

I’ve also attached some screen captures from The Sky X Pro which shows how relatively “easy” it was to locate 2004 BL86.

Main problems were:

the SBIG ST2000XM kept frosting over so I shot at ambient (27ºC) just to record something
clouds were rolling in from the SE.
mosquitos
all fingers and thumbs as this was my 1st outing for several months.


I felt very lucky to have recorded what I did.:)

Cheers

Dennis

[OzEclipse]

Congratulations to those with results Peter, Rob and Jonathan with his great video!

Weather forecast for ACT was cloudy but forecast was for clear sky on the other side of the range northwest of Canberra so I drove 90 km northwest to Bookham. Cloudy cloudy cloud then like magic it was clear. Found a spot near Bookham, spent 40 mins setting up my gear then the clouds rolled in and I only had brief glimpses of patches of sky for the next 2hrs at which point I decided to cut my losses pack up and go home. :mad2:

Similar but slightly different to what happened to me for 2012 DA14. On that occasion, forecast was the same, cloudy in Canberra, clear beyond Yass. it cleared unexpectedly in Canberra and so I decided not to travel, save an hours drive each way and to set up in Canberra.

Result - clouds rolled in as soon as I set up and I could see the clear sky on the north west horizon. Obviously, had I gone out of town, clouds would have followed me past Yass.
:sadeyes:

Joe

[Dennis]

It seems that 2004 BL86 has a moon!:)

http://www.jpl.nasa.gov/news/news.php?feature=4459

Cheers

Dennis

[Rob_K]

Nice shots guys, bad luck Joe & Steve. :thumbsup: Finally got around to processing the 7-sec subs from 26 Jan. Here's a few versions including one of all the subs, 7 & 10 sec. The Goldstone radar image is amazing!

Cheers -

[Tamtarn]

Having spent the past 8 years using a 12" Dob, I recently purchased a 130mm rich field scope with Goto for widefield observing.
So I thought I might try and catch BL86 on the 26th Jan.

I centered the star Hip 38170 and kept looking into my 27mm Pano waiting to see something. Suddenly there it was gliding through the FOV - BL86!
My very first view of an asteroid seen in an EP FOV it was definitely worth seeing! :thumbsup:
Barb

[pdthomas23]

Steve,

Here's my attempt at showing your field in Cartes du Ciel.
Red rectangle is your image.
Labelled red diamonds are the JPL HORIZONS ephemeris for Adelaide.
Times are UT so add 10h30m for CDT.
Looks like it exited your field at about 2115 local.
"Missed it by that much!" ;-)
Note the labelled yellow diamond is where CdC thought it would be using the MPC elements at the standard reference epoch

Peter Thomas
Oakleigh

[OzEclipse]

I generated and entered the elements into Starry Night Pro to create a user defined object. The path was reasonably accurate but the position - timing was also out by 15-25 mins compared to Horizons at different parts of the night. JPL Horizons and the Minor Planet Center Ephemeris service seem to be the gold standard references against which other programs should be checked.

Joe

[kinetic]

Thanks Peter, Joe and Rob for the comments re my image.
Thanks Pete for the analysis and comparison on my field.
I normally do as Joe mentioned, I manually feed in elements into
CdC for a custom object but this night I just used Ian Musgrave's
handy wide and narrow guide maps.
I thought with the wide field combo of the ED80/QHY8 I had a chance
with setting a trap of about 1.5degrees square-ish.
Also, for more critical timings, i usually rely on the MPC online generator too.

I simply should have done better homework.:rolleyes:

As it turned out, the night was a cracker for clarity....oh well, next one :)

Steve

[Rob_K]

Finally got around to doing an animation on 357439 (2004 BL86) - 15 x 7 sec subs, Canon 650D, 200mm lens, ISO 6400, F/5.6 (crops). Image scale is roughly 6"/pixel. 11:45-11:50, 26 Jan 2015 UT.

http://i727.photobucket.com/albums/ww271/Rob_Kau/1%20animation%20fast.gif~original

Cheers -