2023 DZ2

[bigmasterdrago]

Awesome work Dennis. Thanks for sharing. I'm going out now to have a pint for Bobbo.

KY3 never get above the horizon for Phil and I. Sort of a shame since it flirts with the bright 14s! It's brightest when 16LD and near 15th when 12. Tricky Phase % thing.

[Bobbo]

Yeah, thanks 
We had lightning and thunder all night, so no chance of seeing anything except plasma.

[bigmasterdrago]

I got a small window early Saturday morning to make a stab at DZ2 as it moved out of Cancer into Leo. From about 00:00 local until 03:00CDT, this 100'+ sized rock dropped in local altitude but brightened from 13.2 to 12.7 magnitude while moving ~2'/min. I actually found it a bit after 3AM at mag 12.6 moving easily 2'/min but not with the help of ST4. That is in another post but suffice it to say that ST had it plotted very wrong.

[PMSchu]

Hi BMD,

I saw your thread in the Support section of the forum & that you resolved the issue. Dennis captured images on 2023 Mar 23. 

Dennis, how close were the predicted positions of the NEO to your observations? Where did you obtain the orbital elements to determine the position? Did you use ST4 & download the MPC's elements for NEOs at Today's Epoch, or use some other source? You've provided the only images of this object that can be used to compare predictions to observations. Parallax wasn't as severe on 3/23 as at close approach on 3/25.

Phil S.

[bigmasterdrago]

Okay, here is a quick and dirty process of the trail of 2023 DZ2, showing a full res 1600x1600 crop taken from the full frame (6280x4210).

2023 DZ2
23/03/2023 Brisbane, QLD.
Tak Mewlon 210 F11.5
Tak x0.8 Reducer
Focal length: 2170mm at F10.3 (according to plate solve).
QHY268M Pro
68 x 30 secs

UTC: 2023-03-23T09:46 to 2023-03-23T10:28
Local: 2023-03-23 19:46 to 20:28 AEST (UT+10)

Astrometry.net results for 1600x1600 crop.
Center (RA, Dec): (123.466, 19.180)
Center (RA, hms): 08h 13m 51.872s
Center (Dec, dms): +19° 10' 46.844"
Size: 9.52 x 9.52 arcmin
Radius: 0.112 deg
Pixel scale: 0.357 arcsec/pixel
Orientation: Up is 179.6 degrees E of N

Cheers

Dennis

Dennis, if your field size is correct, the motion indicated over the 42 minute exposure looks to be a bit over 3 arc minutes. At a speed then of 7.674498"/min it should be closer to should be a 5.6 minute trail.

[bigmasterdrago]

Okay, here is a quick and dirty process of the trail of 2023 DZ2, showing a full res 1600x1600 crop taken from the full frame (6280x4210).

2023 DZ2
23/03/2023 Brisbane, QLD.
Tak Mewlon 210 F11.5
Tak x0.8 Reducer
Focal length: 2170mm at F10.3 (according to plate solve).
QHY268M Pro
68 x 30 secs

UTC: 2023-03-23T09:46 to 2023-03-23T10:28
Local: 2023-03-23 19:46 to 20:28 AEST (UT+10)

Astrometry.net results for 1600x1600 crop.
Center (RA, Dec): (123.466, 19.180)
Center (RA, hms): 08h 13m 51.872s
Center (Dec, dms): +19° 10' 46.844"
Size: 9.52 x 9.52 arcmin
Radius: 0.112 deg
Pixel scale: 0.357 arcsec/pixel
Orientation: Up is 179.6 degrees E of N

Cheers

Dennis

Dennis, I need to correct my last note. I re-did the track using multiple sources. Viewing from Brisbane from 9:46UT to 10:28UT. The track length is 2.56' long and positioned precisely on your image. Outstanding work. The proper motion at 10:28UT was 3.759485"/min.

[Dennis]

Hi BMD

Thanks for the analysis, what you and Phil do is hard core compared to my space cadet approach.

I ran the Bin 2x2 Frames (taken after 2023 DZ2 had crossed the Meridian) through an App called Tycho Tracker (Phil put me on to this a few years back) which Aligns and Stacks on the NEO thus producing star trails - see attached image.

I also took the individual frames 005 and 010, circled the location of 2023 DZ2 and then combined them in PS CC to show the positions at:

Frame 05
UTC: 2023-03-23T11:34
Local: 2023-03-23 21:34 AEST (UT+10)
 
Frame 10
UTC: 2023-03-23T11:39
Local: 2023-03-23 21:39 AEST (UT+10)

I like data like this which just keeps on giving the more you dig down.

Cheers

Dennis

   

   

[PMSchu]

I didn't doubt that the NEO was where Dennis's images showed it to be  . I'm curious which elements were used to calculate positions that agreed with the excellent images? MPC, HORIZONS?

Phil S.

[bigmasterdrago]

For me on March 23, 09:46 UT from Brisbane, it was/is the MPC. The JPL has it plotted ~2.3" WSW of the MPC position. Lowell has it 2.6" on the same line as JPL. Hardly worth noting.

[bigmasterdrago]

Dennis, that Tak is doing fine work for you. I've got this guy at mid 16th magnitude. Wow! I tracked down a few stars in your other image and came up with easily reaching mag 17.45. Sweet.

---

Dennis, were you able to get any images a couple days later (March 25) when it was moving 4'/min and magnitude 11-12?