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Great question! Yes, I think for starting out the best approach is to practice with analyzing some datasets of already known asteroids. The Tycho user guide gives some examples to follow along with the datasets on the website. Then you can get a good idea of what to look for in a convincing detection. As far as tips to increase the odds of discovery: the biggest help comes from having a wide field of view in conjunction with a reasonable aperture. So this translates to a "fast" telescope, and the RASA telescopes in particular (or Hyperstar) are quite well-suited to this task as they operate at F/2. The next item is the sensor itself: a good sensitive CMOS sensor with enough pixels to make use of the wide field of view is recommended (such as the IMX571). Lastly you will want a decent computer to process the data with reasonable turnaround times.

When there is no transiting/eclipsing behavior, the change to the total brightness is quite minimal and likely imperceptible. You can see that in a few of the 11 photometry sets in this example, where they did not have any noticeable change in brightness compared to the other photometry sets where there was a reduction in brightness (the "bulge" or deviation from the otherwise clean lightcurve).

@@tychotracker Thank you, that makes perfect sense now!

Hi Jerry, yes, the latest version of Tycho does in fact support AAVSO reports, as well as applying transformation coefficients. Thanks.

@@tychotracker Awesome! Thank you.

Yes, you will first want to make sure that the Seestar has been configured to save the individual FITS images (the 10 sec exposures), rather than just the stacked image. Then, identify an asteroid for which you would want to generate a lightcurve. This can be tricky because there are not too many that are bright enough, have a reasonably short period (less than 8 hours ideally), and sufficiently resolvable amplitude (at least 0.5 mag would be good for Seestar). You can use the Lightcurve Database in Tycho do a search with criteria and help identify an initial list of candidates. Once you have selected an asteroid, you can generate ephemeris for it to determine where it will be in the night sky at your location at certain times... Using this information you then know the RA/Dec coordinates of where to point the telescope to start the image collection process. Since the Seestar does not accept RA/Dec coordinates (this is something they ought to add!) then you will have to simply bring up the sky chart in its app to point it at the coordinates. Good luck! That's why this is called a "Challenge"!

@@tychotracker Hi, I am still learning, there are many terms that's new to me >_< ... seestar can add RA/DEC coordinates now. :> it will be good if there is a step-by-step video tutorial... Thx

Hi, is there any known bright asteroid I can track these days? Is there any website I can get more info.? Not sure if seestar has the asteroid database... Or can I just track the M31 and treat it like a moving object in Tycho for testing? Thx

Btw, the Tycho software introduction I found is 4 years old... Is there an introduction for V11? Thx

@@AndyKong51 I used the lightcurve database in Tycho as a starting point. This is available from Tools->Lightcurve Database. You can then apply filters on magnitude and rotation period. Once you have a few candidates, you can use the Session Planner tool to generate ephemeris for each, and determine when they might be at decent viewing elevations.

Thanks for the questions. There are some datasets available on the Tycho website, I will see about adding this one. For the second question, I used the JPL Horizons service to generate an ephemeris. Tycho also features a module to interface with JPL Horizons in an easy-to-use fashion: you can supply it with the object name/number, and it can populate the Session Planner table accordingly.

Yes, I have looked at in the past, and while that generally holds true, it can still have a somewhat wide range of 30 degrees or more. For example, if it so happens that the artifacts are centered at PA of 260, plus or minus 15 degrees, then that coincides with the position angle of a large portion of main belt asteroids.

@@tychotracker true, but asteroids would generally vary in speed, while camera induced artefacts would all have the same speed and movement in that timeframe. That could easily be spotted by the software, and maybe filtered into another class “possible artefact” next to the high, medium , low and none?

There are other free software, however I find Tycho to be the best and easiest to use option, combined with routine updates and support. And it also now supports operating natively on macOS computers. As for 2024 MK, as it makes a close approach and moves fast in the sky, one option is to use shorter exposures, provided that the SNR is kept adequate, while another is to use half-rate tracking such that both the stars and the object itself are somewhat streaked (but still avoiding too long of an exposure). The latter option would only apply to the other mounts, while Seestar should be capable of supporting the object motion with its 10 second exposures.

@@tychotracker Thanks! However, since this asteroid is likely to be fairly dim, would the Seestar even be sufficient to capture it without stacking? Magnitude 11+ and traveling through the frame. Also, the fairly narrow field of view given the rate of movement - one would need to track the asteroid by reframing sky targets it will cross "leap ahead" style... what would be the minimum aperture and ideal focal length you think could be good for capturing the asteroid as a streak (in Bortle 8 skies)?

@@TalGivoly In decent skies the Seestar would still see a mag 11 object, however indeed the SNR at that magnitude would likely be low enough that it would be difficult to identify an accurate rotation period. As for minimum aperture, hard to say because it is a combination of camera sensitivity, aperture, and sky conditions that lead to the resulting conversion from photons to electrons. Same with focal length, as it depends on the size of the camera sensor. But probably one example configuration that could do it is a RASA 8 paired with a ZWO 2600. This would offer a field of view of 3.3 x 2.2 deg^2, which would ensure that the object is visible in the field for a reasonable amount of time. And the 200mm of aperture would certainly be capable of magnitude 11.

@@tychotracker Well, I have Bortle 8 skies, and tonight this asteroid will be going straight from the Eastern horizon towards the zenith. I'll try to recreate what you have just suggested. I do not have a 8"m RASA. However, I do have an 8" Quattro F4, but that would be 800mm focal length and too narrow a field. Instead, I'll use a Canon 200mm F/2.8 lens and ASI294mc Pro on one rig, the Seestar, as another, and an 8" Dobsonian for visual viewing of the rapid movement. The nearest object of interest it shall be passing is M15 - and the widest rig should be able to capture that... let's see what I come up with. I might also pull out the Quattro to try to capture the asteroid buzzing by, perhaps with an APS-C sized sensor... that should give high resolution and if it has a high orbital rotation period, it might even be caught in the frame... Thanks!

Thanks! I am happy you find it interesting. At the time of this video the two main stacking processes were average (mean) combine and median combine. Median combine is quite good at rejecting outliers, but can sometimes produce a somewhat artificial result. The latest version of Tycho also adds Ksigma combine which allows one to perform averaging while rejecting outliers beyond a certain standard deviation. In terms of speed, it is very much on par with the other two as it has also been implemented with GPU acceleration.

If the images do not have a plate solution (WCS information), then it is easy to enough to add one -- navigate to "Action->Plate Solve Images" from within Tycho and it can proceed to attach WCS information from the solution it finds.

Thanks for the question. The images were captured using a Samyang 135mm lens, paired with an ASI 2600mm (IMX571 sensor).

thank you!

A common step involving multiple nights is that one must apply lighttime correction and (H-G) correction in order to have the datasets line up on the graph. The software does this automatically once the object data has been applied to the photometry sets. However, a further complication can arise if one does not use solar color comparison stars, or for other reasons the comp stars deviate from night-to-night, requiring what is commonly referred to as a "nightly offset" to line up the dataset. I did have to apply a nightly offset, but doing so was easy enough because each night captured a full or nearly full rotation, so it was possible to simply compute the offset as being the difference between the median (absolute) magnitude values.

It is a Rokinon/Samyang 135mm lens, also available on the iTelescope network as T80. Very wide field, but you won't be reaching very faint objects (at least, certainly not with 10 second exposures). That said, it makes for a good test platform for these kind of objects.

Thank you

thank you! I am happy to hear you are finding it useful for your work

Thanks! I used the Tycho software to generate the photometry measurements.

I used the Tycho Tracker software to process the images and generate the measurements

The four nights of data adds up to about 12GB, so if you send an email to the Contact page on the Tycho website I can generate a download link for you that way.

I was pleasantly surprised by how well it performs, especially given that I live in Bortle 6 skies.

@@tychotracker I'm actually surprised at the results! I mean you got almost everything stacked against you ... alt az mount, tiny scope, tiny sensor, colour, light pollution... I can't wait to get a 3d printer and play with my C11 and a coma corrector wit a tiny camera on top... should be interesting 🤔 that's a really inspiring video! well done 👍

Asteroid lightcurves can be submitted to the ALCDEF database.

Ideally you want the exposure time to be just long enough to maximize SNR but short enough that the object does not streak beyond maybe a few pixels, so that you can ideally work with a circular aperture if possible (and also to minimize the chance of the streak spreading into stars and thus contaminating the result). I would recommend using the exposure time calculator to determine the optimal time for a given plate scale and object speed. This is accessed by going to Calculators->Optimal Exposure Time from the main menu.

@@tychotracker thanks!

You can give it a title by going to Graph->Settings and either specify a title manually or have it use the title from the object name (assuming you have attached object data to the photometry sets).

@@tychotracker that i was searching, yes i put the title manually, but having loaded and attached object data to the photometry test i was assuming automatic process. i will try again. however .. absolutely astonishing process and software .. i found the period of that asteroids, that was 17 mag at the time of observation, about 185 minutes, the MPC provide 190 min.. my results were based on not dedicated observation, the asteroid was at the edge of the frames and the subject was NGC 2339 .. really many thanks for your great work! i purchased almost immediately the full license ! great software. Now ... next step ... analysis of an image and check with Tycho the eventual presence of asteroids known and unknown object in case .... which tutorial do you suggest me for this ?

I second this question -- an ability to do this would be very important for exoplanet hunting, to discover new ones with streamlined efficiency.

thank you very much!

Yes, for seeing basic motion of a moving object, you can use JPL Horizons to attach ephemeris to the dataset. Here is a quick tutorial explaining it: ruclips.net/video/M_TGGs0wSUM/видео.html

Sure, as I mentioned in another comment, one way (of several) is to use JPL Horizons. Link to a tutorial video: ruclips.net/video/M_TGGs0wSUM/видео.html