We essentially compare these images against each other to make sure it is something moving. One of us on the science team will look at the markings and determine if the marking is good or not, there has to be at least 3 markings (I think) close to the same location for it to even get reviewed as good (we see them all, we just automatically mark it as bad on the way in if it has few markings). This takes out the mistake markings, weather someone clicking randomly or a marking on a cosmic ray strike. If we have a good marking in the same location at different times then we say that it has to be a variable star blinking on and off. If there is a good transient marked in the image and another is not seen at the same spot (meaning it is not a variable star) we mark that differently in out database. From there, we know about how fast they should be moving so if we have 2 markings that are the right distance from each other over the right amount of time we have a program that will show us those images so we can link them up. However, we like to get at least 3 in a visit to make sure that it is not just 2 variable stars that are bright at the right times and spaced correctly.1. When you have a marked transient on an image, how do you tell if it is a KBO, a variable star, an asteroid or just a mistaken marking? I understand that you have a series of images of the same part of the sky. Do you then compare these images against each other (and how do you do this?) to see if the object moves?
Asteroids usually appear to be slightly streaked as they are moving much faster than KBO's, this is something that we can change in the review process. However, if one gets by, its not a big deal, we will be able to see if it is an asteroid after fitting an orbit to it and seeing that it is very close in.If it does move then it would seem to be either an asteroid or a KBO, but how do you tell the difference?
Yes it is possible but hard. If you have enough good measurements and the data is taken at opposition, you can get an orbit with fairly low errors after 4 or 5 days. However, longer arcs will make for much better orbit calculations so more is always better in this case.2. I understand that the images of the same area of sky are taken hours or perhaps a few days apart. Is it possible to determine an accurate orbit with images taken just a few days apart?
Much of this data on this site is taken close to quadrature (which maximum elongation but outside of Earth's orbit) we call it the 'confusion zone'. At this point asteroids and KBO's can appear to move in very weird ways if you do not know their orbital properties yet. Here is an illustration to try to show what Im talking about:3. Why is it more difficult to determine the orbital parameters of asteroids vs. KBOs? I would have thought it would be easier to determine orbits of things which move more in a few days than things that move less.
At this point of quadrature, asteroids can appear to move at the same rate as KBO's and they can both move in retrograde patterns which makes it very hard to start getting an orbit.
Yes we do check. You should not see any KBO's marked as asteroids, maybe the other way around (which is not as a big of an issue). When we mark something as an asteroid we do not consider it for first round MPC submission (as this project is focused on KBO's) or to look at as a NH candidate (because NH has already passed it). So, if you do see this, please bring it up and we will take another look at it. But this should not happen, once we have something as an asteroid, we usually have a pretty good orbit for it and can safely throw it out of the running for NH.4. Do you also check if marked asteroids might in fact be KBOs? Sometimes its hard to tell if a blob is round enough to qualify as a KBO.
It was that day.5. Is the SHIFT key not working on your keyboard?
Thanks for explaining that, borncamp!
We much appreciate these excellent explanations.
The panel that showed our stats seems to have disappeared since last week I was on.
The "My Ice" statistics are missing from the search window. I re-logged on several times but it is not populating on the window. Did we have a software change or build that could have caused this? Thanks for your efforts in addressing this.
Hi dennispattensr, I moved your post to this thread. There was an upgrade last night.
And of course: Welcome to CosmoQuest!
Conceivably you could have wrote apologies in the region left by removing the stats. Even with a link to this thread Or a stickied "Issues with Ice investigators" thread would make more sense.
My stat is returned .
Great job to all the team.
Funnily enough, when there was no stats I was less perturbed about tagging uncertain objects. With stats one has loss aversion over diminishing ones marked:confirmed ratio. It'd be interesting to see if people tagged more when stats were down.
It's like psychology ontop of astronomy
Did something happen to marked:confirmed earlier? I suddenly noticed I have more confirmed than marked....that can't be right surely...
Something clearly went BOINK! when we rebooted after the Amazon crash. Let me get Cory to fix.
This and many other things will be fixed on a very large update Friday. Expect awesome things then.
Does anyone know what the huge white blobs are with the black lines/blobs in the middle? I don't think they are transients because of the black lines/spots.