How fast does 4 Vesta move?

[jrkirkham]

This is just for fun and a VERY rough estimate. My observations may be off. My math may be off. I am not taking into account the locations of earth and vesta. That said, for several nights the first week of this month I tried to an eye on Vesta. I tried to estimate its speed and came up with something around 37.5 arcseconds per hour. Have any of you tried estimating the speed of an asteroid? Does this see like a reasonable number?

[yobbo89]

i wounder if astrometrica can measure this

[Sky]

Checking (4) Vesta on TheSky 6 software, shows its current motion as 34.5 arc-sec/hour.

[jrkirkham]

Thank you. I did better than I hoped for. That amount of error could be caused by imprecise charting. Five nights wasn't that many for such a small object moving so slowly.

[ARock]

Thank you. I did better than I hoped for. That amount of error could be caused by imprecise charting. Five nights wasn't that many for such a small object moving so slowly.

If you took images of Vesta, you could platesolve the images, and figure out the RA/Dec of Vesta on each night. You need to have the astrometry.net tools locally running on your computer to do this, the distro has tools to do this although it is not automated. That would give you an accurate speed.

[jrkirkham]

That's one of the things I like about astronomy. It seems like you never run out of new things to learn. This year was the first time I've paid much attention to asteroids. I started with Ceres. I found it and plotted it. Then I went for Vesta. I found it, plotted it, and attempted to figure out how fast it was moving. I didn't use any tools other than a star chart. I tried to come as close to plotting Vesta's location as I could each night. I only used a camera with a 50mm lens on a tripod, so that kept me from coming too close. I then took a simple ruler and enlarged the star chart until 10cm = 1 degree. I used the ruler to measure about how far Vesta had traveled and divided it out. It was very unscientific. The next time I try that I'll have more tools at my disposal. I think if I had used a telescope, or even a longer lens, I might have been able to come a little closer. I have to say it was fun.

[MistrBadgr]

Hi Rob,
I would say, considering the tools at hand, you hit the nail on the head on Vesta's speed across the apparent sky! I enjoyed reading about your procedure. It sounds like the kinds of things I do sometimes.

[Sky]

That's an amazingly accurate result, considering that the scale of 1mm on a ruler equals 3.6 arcseconds. If you want to learn the mathematics of astrometric measurements, then check out this web page:

http://spiff.rit.edu/classes/phys373/le ... strom.html

It's well written and easy to follow the mathematics behind the 7 step process to get an astrometric solution. It uses the asteroid 1107 Lictoria as an example.

Thanks for posting your results ....

[Makuser]

Hi Rob. It appears that your efforts were extremely close to the "official" movements of 4 Vesta. I really enjoyed your interesting report, and it shows what a dedicated amateur astronomer can do. Thanks for posting this thread Rob, as there are quite a few minor planet enthusiasts among the members on here.

[Ruud]

  
Stellarium shows a movement of 0.189° over 24 hours starting at about the time of this post. That's 28.4 arc seconds per hour.

[alexwolf]

Stellarium shows a movement of 0.189° over 24 hours starting at about the time of this post. That's 28.4 arc seconds per hour.

You may just select Solar system body to get the hourly motion info

[Ruud]

@alexwolf
Thank you for your input, Alexander. I use custom info options and it has been a long time since I made inventory of everything that's available there. I'll check it out now.

Stellarium is the best and we are all truly grateful for the work you put into it!