Asteroid (66391) 1999 KW4 set to make close approach - binary object

[gary]

Asteroid 1999 KW4 will pass by Earth on May 25, 23:05 UTC at a distance
of 5,182,015 kilometers.

The 1.5m km diamater asteroid has its own moon, that is, it is a binary system.

It is expected to reach mag 12 and might be visually observable in as little as an 8".
It will be up in Puppis.

Story here :- https://www.cnet.com/news/walnut-asteroid-nearly-a-mile-wide-seen-approaching-with-its-own-moon/
More here :- https://earthsky.org/space/double-asteroid-1999-kw4-closest-may-25-2019

[AstroJunk]

Spent a couple of nights observing this little rock(s) - Here's my best video of it from tonight:

https://youtu.be/uv8wbeOTJk4

[atkinsonr]

mate, that's awesome

[multiweb]

Nice catch.:thumbsup:

[AstralTraveller]

Great stuff! Totally fascinating. I couldn't wait to see how it ended. :P

I'm interested in the technicalities. What was the mag of the asteroid and what was the faintest mag seen? Also, what is the fov? Your web site says you use a TACOS_BD for occultations but this was done with a ZWO. New camera?

[AstroJunk]

Thanks all!

David, yes I tend to use my ZWO ASI174MM-cool for everything now as it has many advantages of er the TACOSBD and only one issue - it can't be used with a video time inserter. The issue has been easily remedied with an NTP stamping protocol which gives me an absolute time base of +/- 2ms.

The asteroid was around 12.6 mag at the time, so the fainter stars are 15 and beyond. The FoV I used was about 30" across. I used a region of interest of 1280x720 and rather over exposed the image so that it would transfer to video without the need for post-processing. I am lazy sometimes :)

[multiweb]

Good article with pics from the ESO: https://www.eso.org/public/news/eso1910/