13 replies to this topic

[dahbi]

Hi everyone,

 

First of all, sorry for my english. I'm not a native speaker, I use an online translator.

 

I'm not sure that my subject is in the right section, but I still ask you the question in this topic.

I read on a forum that in amateur astronomy it was possible to establish an observatory code with the minor planet center.

 

My questions are the following :

1) Is it possible to achieve this goal using only a camera DSLR or do you need a CCD camera ?

2) What is the exact protocol because I can't find anything  on the JPL website about this subject ?

 

I observe from Morocco Where the amateur astronomy community is almost non-existent.

I use a 200 mm Telescope, f/d = 10, with a Optec reducer. I have a camera DSLR.

 

Thanks to those Who have obtained this famous code ...

 

[StupendousMan]

The information you seek can be found at this location:

 

    https://www.minorpla...Astrometry.html

 

Read item 13 in particular.

[RedLionNJ]

Hi everyone,

 

First of all, sorry for my english. I'm not a native speaker, I use an online translator.

 

I'm not sure that my subject is in the right section, but I still ask you the question in this topic.

I read on a forum that in amateur astronomy it was possible to establish an observatory code with the minor planet center.

 

My questions are the following :

1) Is it possible to achieve this goal using only a camera DSLR or do you need a CCD camera ?

2) What is the exact protocol because I can't find anything  on the JPL website about this subject ?

 

I observe from Morocco Where the amateur astronomy community is almost non-existent.

I use a 200 mm Telescope, f/d = 10, with a Optec reducer. I have a camera DSLR.

 

Thanks to those Who have obtained this famous code ...

You wouldn't find anythng on the JPL website because JPL has nothing to do with the assignment of MPC codes. They are assigned by the Minor Planet Center, as member StupendousMan implies, above.

 

Getting an MPC code is easy - take measurements of the positions of six middlingly-bright (16th mag or fainter) minor planet positions (3 per body per night), one of which must be a relatively fast-mover (NEO). Submit these measurements in a single batch to the MPC and, if they are deemed accurate enough, Peter will issue you a code within a few days.

[pbealo]

I believe 1st observations should be below 14 mag, NOT below 16th mag. See MPC requirements below.

Peter

 

How do I begin?
If your site does not have an observatory code, one will be assigned upon acceptance of your initial submission. Your initial submission should contain at least six numbered minor planets each on pairs of nearby nights as well as one numbered Near-Earth object observed on two distinct nights. If weather interferes, the two nights can be some weeks apart. Report at least three observations of each object from each night: do not report single positions per night. Batches that contain single positions will be returned in their entirety to the submitter. We will check these positions and advise you on their quality. As a general rule we advise you NOT to observe very low-numbered objects--e.g., (1), (2), (51) and very bright objects. In your initial batch please submit astrometry of objects fainter than 14th magnitude. In addition, you should try and observe objects of various brightnesses. We require astrometric accuracy to be within 2 arc seconds from the predicted ephemeris. We will not assign the observatory code if you do not fulfull the criteria above. Example of a minimum data submission in a plain-text format is here.
You should not start by observing fast-moving objects! It is important that you gain experience by observing "routine" objects before attempting to observe "unusual" objects. We also expect you to prove that you can produce good astrometry of known objects before you begin to discover new objects.

Even if you interested only in comets, it is required that you follow these guidelines for your initial batch and not submit comet astrometry. In general, comets are harder to measure than minor planets. If we have a new observer reporting comet observations of bad or indifferent quality we do not know if it is simply a problem due to the comet (big, bright difficult-to-measure image) or a problem with the measurement/reduction process. If we have received minor planets from a new observer in the initial batch, we will have already have determined that the measurement/reduction process is acceptable.

[RedLionNJ]

I believe 1st observations should be below 14 mag, NOT below 16th mag. See MPC requirements below.

Peter

 

 

Anything below 16th magnitude will also be below 14th magnitude.  There are very few "interesting" objects brighter than 16th magnitude, and in particular, the requirement for an NEO may push one down even fainter, perhaps to 17th or 18th magnitude, unless imaging is done at a very serendipitous time (but that leads to fast-movers, which beginners are advised to avoid).

 

Realistically, you need to be able to measure positions of objects at least as faint as 16th magnitude, ideally fainter.

[pbealo]

What you say is all good in an ideal world. But if the goal is to get an MPC observatory code, I see no reason to make the process more difficult than MPC requirements. If their requirement is, among other things, to image n asteroids below 14th mag, there is no reason to make it harder than necessary and go for sub 16th magnitude. That can come over time.  

 

If MPC changes the requirements, so be it. But passing along overly aggressive pseudo-requirements is just not useful IMHO. Its not up to you or I to set new, tougher, requirements.

 

Peter

[Benito]

Ther are plenty of 14th and below magnitude bodies to image.  I used the NASA JPL Small-Body Database Query and use 14.5 mag as my limit to stay below their 14th mag criteria and work through a list of 6 asteroids plus 1 NEO.   https://ssd.jpl.nasa...sbdb_query.html

[Xilman]

There are very few "interesting" objects brighter than 16th magnitude ...

I beg to differ.

 

Several teams, of one of which I am a member, are engaged on time series photometry of asteroids with a view to determining their rotational periods.  Almost all interesting targets we observe are brighter than 16th magnitude and frequently brighter than 15th. A few exceed mag 14.0 for at least part of the observational periods but these are admittedly rare. The BAA team studies a dozen or two every year and there is no end in sight for targets for quite a few years to come.

 

It is relatively uncommon, but not very uncommon, for measurements down to mag 17.0 or below to be taken on asteroids which are well away from opposition but which are still of interest.

 

FWIW, I am J22.

 

Anyone wishing to contribute to this valuable area of asteroid research is encouraged to contact me for more information.  Realistically, you need a 20cm (8") or larger telescope and a CCD or CMOS camera (the later includes a DSLR camera).

[RedLionNJ]

You are, of course, correct, Xilman - photometry can be applied to any brightness of object and there are very few minor bodies where the light curves have been determined to such a degree of accuracy that we can't glean any more information from additional measurements.   But not everybody is into photometry (and, quite honestly, I don't see how the MPC requirements for obtaining an observatory code are relevant to measuring brightnesses) and the MPC expectations are for proof one can execute accurate-enough astrometry.

[jfgout]

Hi everyone,

 

First of all, sorry for my english. I'm not a native speaker, I use an online translator.

 

I'm not sure that my subject is in the right section, but I still ask you the question in this topic.

I read on a forum that in amateur astronomy it was possible to establish an observatory code with the minor planet center.

 

My questions are the following :

1) Is it possible to achieve this goal using only a camera DSLR or do you need a CCD camera ?

2) What is the exact protocol because I can't find anything  on the JPL website about this subject ?

 

I observe from Morocco Where the amateur astronomy community is almost non-existent.

I use a 200 mm Telescope, f/d = 10, with a Optec reducer. I have a camera DSLR.

 

Thanks to those Who have obtained this famous code ...

 

Several responses in this thread have already answered your initial question. You can absolutely use a DSLR camera, although it is not as ideal as using a monochrome CMOS/CCD. Pay attention to the pixel scale recommended by the MPC (see the link in the first reply).

Since you are in Morocco, you could try to get in touch with the Oukaimeden observatory. It is a top class observatory and they seem to do a fair amount of public outreach. There might be people there who can help you.

 

Best of luck !

 

JF (W05 - I've obtained my MPC code only a few weeks ago...)

[Xilman]

You are, of course, correct, Xilman - photometry can be applied to any brightness of object and there are very few minor bodies where the light curves have been determined to such a degree of accuracy that we can't glean any more information from additional measurements.   But not everybody is into photometry (and, quite honestly, I don't see how the MPC requirements for obtaining an observatory code are relevant to measuring brightnesses) and the MPC expectations are for proof one can execute accurate-enough astrometry.

You are right, of course, and I was getting ahead of myself. Once dhabi gets up and running he should, in my opinion, learn how to do photometry (assuming he does not already) and get twice as much return on his investment.

 

However, I am firmly of the opinion that when one takes data, one should attempt to be as productive as reasonably possible and extract what one can. This applies to all areas of observational and experimental science, not just asteroidal astronomy.

 

FWIW, astrometry doesn't do much for me, by and large, but I do measure positions as well as brightness when there is value in doing so.

 

Paul

 

P.S. Congrats on getting your code.

[apearce]

I was able to measure and report astrometry for 14-15th mag asteroids and NEO's and obtained a MPC code (P14) for my Seestar in my Bortle 6 backyard.  The targets do not need to be 16th magnitude.  It also did not take too long to wait for a brighter NEO.  The most important thing is the residuals from your measurements.  My Seestar was able to achieve less than 0.5-0.6" consistently.

[RedLionNJ]

I was able to measure and report astrometry for 14-15th mag asteroids and NEO's and obtained a MPC code (P14) for my Seestar in my Bortle 6 backyard.  The targets do not need to be 16th magnitude.  It also did not take too long to wait for a brighter NEO.  The most important thing is the residuals from your measurements.  My Seestar was able to achieve less than 0.5-0.6" consistently.

That's very nice (seriously), but astrometry is generally sought for objects in the fainter than 16th magnitude range (with the exception of fast-moving NEOs and they present a whole other capture dilemma). There is little value in attempts to further refine orbits of anything "bright" - their orbits are generally well-known.

 

As Paul correctly points out - photometry can be done on brighter objects, but (as far as I know) that doesn't require an observatory code as measurements are not geographically-dependent (and there is no "photometry test" as part of the MPC observatory code requirement).

 

I also have a SeeStar which I set out on a picnic table in my backyard while I use my main observatory rig for more demanding purposes. With reasonable skies (I'd put mine at B5-B6), you should be able to get down to 18th magnitude with it. This puts the brighter TNOs within range - and about 30,000 other minor bodies. I captured Haumea this past summer, with residuals well under an arcsec. I'm pretty sure, had it not been summer, I could've reached m19 with the SeeStar S50.

 

Anyone can participate!

[Xilman]

Very good to see someone using a Seestar for observing and measuring faint objects as opposed to taking snapshots of photogenic ones.

 

I get ever more impressed at the capabilities of the SS50. For instance, mine has successfully imaged a 17th magnitude galaxy in a B5 sky with only 11 minutes exposure.

 

Not only TNOs are within range, satellites in the outer solar system are also possibilities. Phoebe, for instance, is about mag 16.5 and well separated from Saturn for much of its orbit. It would be interesting to see whether Nereid could be picked up at mag 19.1.  The latter could be rather challenging astrometry though. Synthetic tracking would almost certainly be needed to make its image measurable.