hello everyone we are going to continue uh using astrometric and seeing how we can look for asteroids in our data so let's start we first have astrometric open go ahead and open it from your desktop now the first step is to check what is your PS1 or PS2 configuration so go ahead and check you can see it down there so we have first check that it has to match the data set we are going to be opening so how do we check that we go to the first icon which is program settings ignore all the tabs that have come up just click on open the button below you'll see a whole bunch of config files each configuration files corresponds to a telescope so if I want PS2 or PS1 I'm going to say open then come back and say save and okay now whatever you have below should match the settings uh of the data set you're going to use now let's start the first step is file load images because like with any software we have to start off with some files so so file load images is the first step click on that now browse and find where did you save the data that you unzipped okay so when you find it you navigate your way and find it and that should have four files the four are time series of one part of the sky okay so what you do now is select all of them I selected with with the shift uh you can select it with contr a or just do it one at a time but pull in all four okay so now when it loads you will see four images on your astrometric desktop so these are all images four Images they are 4X four squares so it's a 16 size grid you can scroll up and down okay uh one way to change the color is there's an icon here below Windows called invert images so it's up to you what you choose now you have the four images on your desktop so let's go to step two step two is astrometric data reduction let's click on that that's the icon with a green diamond so it's has coordinates on top and that is what the step does it puts coordinates on your images right now the software does not know where it is okay don't type in anything just click okay and it takes a bit of time what it's doing is it's connecting to a reference star catalog which is somewhere outside and it compares the stars and based on that it tries to find which part of the sky your image is located in if it's taking time don't don't worry it takes some time sometimes okay so it's done for me when this table pops up it's done okay what is this table it is just telling you how well the fit happened you don't have to worry about this you can cross and get out of this table you'll also see some of the stars are marked in green and those are the stars that were matched so you always have to do that step after you've uploaded the images now for step three step three is something called known object overlay now that is the icon right next to the magnifying lens button okay so you click on that again it takes some time it's connecting to the MPC database so some of you if you had an error while installing that said MPC error then this step may may not happen properly but for everybody else soon there will be some uh names coming up labeled in red and those are the known asteroids in this field if there are no known asteroids then there won't be anything but for the training data that I'm using there are about four such objects okay now we are ready to Blink and look for asteroids so let's start blinking blink current images we click on this icon it's next to the number one okay and you'll see when you start blinking it then the next four buttons also show up and those are the Stop and Play and one step forward button okay so these are uh the buttons right here okay so these are the buttons right here and uh they will help you stop the blink or play the blink uh in case uh you don't see these buttons you can go to tools and you'll see it under that as well okay so now I can see the blinking window I have to look for moving objects okay so there are five rules to look for a moving object I'm going to take you in this training data set to a moving object that I already know is there and how do you find that you scroll down and it's on the window to your to the to the second Square on the left okay you see a moving dot there so that is what we are going to work with and try to show you how to identify it there's a small dot okay so now there are five rules to know if an asteroid is really an asteroid the first rule is visual first and second rules are visual is the DOT moving in one straight line and at a constant speed it could be left right up down diagonal like it is here but it should move along the same path it should not fluctuate or oscillate okay here it is moving in One Direction and uh at a constant speed so we have the visual tests passed now we stop it we're going to explore further now on top it says image two so with these arrows I'm going to go forward till I come to image one let's start with image one that's where we'll mark our object so first we click on it click on the dot that you suspect is an asteroid and a window will come up that says object verification so look at this object or the top window circles the object you have selected come down below that there's an information window the last line are the coordinates which is RA and de right Ascension declination and there's another value called R now that is your third test R is brightness or magnitude this R should stay the same when when I go across all the four Images because a brightness of an object does not change between locations and through time it there could be error margin instead of 18.4 maybe you have 18.9 or uh 18 but it should not jump up or go down a lot okay that was Point number three you check the r Okay so we've checked the r now we go to point number four remember we are doing a fivepoint test to check if this is an asteroid Point number four you check these white dots up here and see are they lining up with the red curve the red curve is what a celestial object signal should look like and the white dots are what you have selected in the circle that you have so in this case it lines up pretty well some cases it may not line up so well but it should still show some of the signal and not just be like a straight line now let's look at the fifth Point that's this value SNR signal to noise ratio what does that mean how bright is the signal of this object compared to the background noise now the higher this number is the better okay so uh it means here that the signal is 28 times brighter than whatever is there in the background so U if it's very low like two or three then I would doubt if there is signal so here it's very high and the number cut off you have to look for is five so it should be five or higher if it's lower then you need to check with your Mentor uh and get it approved okay so finally now that I'm almost ready to check it there's one more thing we have to do and what is that now that we're ready to mark it as an asteroid we first have to check is it by chance and already known asteroid so this is where we're going to Mark the asteroid name but first we're going to check by clicking on the three dots below object designation okay again it's going to take a bit of time and it's going to pop up a table and that table tells you which are the objects known objects in the catalog that are close to the object you have selected so you only need to look at the first line which is the closest to you so you you need to look at these values d a and DDE which is the little d means the distance or the difference so it's how much distance there is between the known object and the object you have selected in both ra and deck and if both these numbers are zero that means that they're very close they're on top of each other and they are so you've not found a new object at all you found the known object but here it is not zero it's larger don't worry about the plus and minus sign that just means right left so this is larger so we don't have to worry about it but in case it was zero or very close to zero like point3 then you should click on okay and accept that name but in this case it's not it's further away so we are going to go for cancel okay and we're going to give it a new name the name always has a certain format please remember this three letters in capital and four numbers the letters can be ABC XY Z DPS your initials your partners initials it doesn't matter because it's just a sequence if you get a Discovery the name will be change uh so let's I'm going to call it XY Z then you have to give give it four numbers so I'm calling it 00001 okay now you can vaguely at least remember the number you gave now you have to remember the number you gave okay so now it can be seen on my image so now I have to mark the same object in the remaining three because what am I trying to do I'm I'm trying to show I found an object and how does it change over the four images okay so I do single step forward again I click on the same object because I'm marking it and let's redo it because I didn't mark it too well okay so now again I have to check the r was it last time it was 18.4 yes it's still close is 18.7 the white dots line up the SNR is is good and now I'm not going to check object designation anymore because I've already checked it once I have to name it the same name because it is the same object that I'm naming over all the four images okay now I quickly go ahead and do it in the next two I'm just going to name it now I'm not doing anything else okay so remember you have to give it the same name uh so I do that XY Z 00001 okay so I've accepted it now make sure you marked it in all the four Images now I'll just show you one more thing so I'm going to Blink it again what happens if there are more asteroids you have to take your time and look for more now there is one more here since it's a training data set we know where it is okay there's one here okay moving dot so again I'm going to repeat the same steps very quickly I'm not going to do all the checking but here I checked is it a straight moving in a straight path okay so again I forward it to one I click on it and now I have to call it something different XY Z 0 0 02 if I forgot it I can go to five but don't name it one because that's done okay so now again I quickly go and name it four times because every time you have to name it four times okay yeah so this is XY z 00002 now I do it four times and then I'm done okay so let me Mark it okay and one more time that's XY Z 00002 yeah so if you mark a little bit wrong which I had done you can see that uh the signal hadn't lined up okay so now I marked two objects so now I can look at the report that's a final step how do you see the report you go to file view MPC report file you know the word MPC minor planet catalog and report so remember the word report text file pops up and it's got a header part and it's got four lines per object that You' selected so x y z 00001 has four lines and just these numbers are a bit different because these are what shows that it's moving in your four images okay so for each object you selected there should be four lines that is something you should check here so check the format do you have three letters and four numbers and four lines per object and then finally you're done you just have to copy this now select contrl C or you can do copy and you can save it in a notepad or you can directly copy and paste it to the web page so this is how you do uh use as how you use astrometric to look for uh asteroids and if you see a moving object you can mark it and save it in the report and this is the report that will be copied on to the web page thank you