Ancient Asteroids Observing Campaign

How to get involved to the observing campaign

Are you a professional or a motivated amateur astronomer? Do you have access to a professional astronomical observatory or you have your own astronomical equipment along with a CCD camera? Then, this project suits you perfectly. In order to get involved in our project follow the instructions and guidelines, perform the desired observations, submit your data and contribute in the Ancient Asteroids project.

Instrumental Requirements

The asteroids, that are going to be observed, are quite faint and therefore serious equipment is required in order to achieve high signal-to-noise (S/N) ratio. Please, see the below the minimum requirements that are eligible to allow you getting involved in our project.

Minimum instrumental requirements:

• A telescope with aperture at least 30-40 cm in diameter. No special preference for the telescope type (refractor or reflector).
• A digital CCD/CMOS camera with high QE (>60%). No filters are required. Clear aperture is prefered, in order to increase the recorded signal.
• A signal-to-noise ratio higher than 50 is required. S/N > 50 is highly suggested.
• An accurate time recording device, set to Coordinated Universal Time (UTC). This could be an online NTP server or GPS time recording device. For example, you can download and install the following application: NetTime

Observing limitations:

• Capability to detect faint objects, greater than 14 mag, in less than 5 min exposure time.
• Exposures cannot exceed 5 minutes, as the asteroid rotates fast the the light curve shape is rapidly distorted.
• The telescope and digital camera should produce image scale greater than 2 arcsec/pixel [use the formula: Scale = (pixel size in mm)*206265/(focal length in mm)].
• There is no special preference in binning mode (1x1, 2x2, 3x3 or other), as long as the above criterion is meet.

What to Observe

The purpose of the campaign is to collect photometric observations in optical wavelengths, of asteroids that belong to old collisional families. The observations will be used to produce light curves (see Figure below), which are the results of the asteroid's rotational and morphological properties.

The rotation of an irregular 3D object, causes different areas to reflect sunlight towards the observer. This results in variable brightness of the observed object. Careful analysis of the periodicity, amplitude and light curve shape reveals the rotational and morphological characteristics of asteroids.

The sample of asteroids, which are subject to be observed in the frame of Ancient Asteroids Project, can be found under the List of Primordial Family members.

Investigating the most ancient asteroids

Observing Guidelines

In order to perform valuable and useful data for our project, please follow the observing quidelines strictly.

• Run the online  Web Application  and identify the asteroids that you can observe from our target list, based on your location, the observation period and a couple of requirements/preferences. (It takes a while for the application to open due to the server limitations, so be patient). Instructions for using the Web Application can be found here.
• Choose a target from the extracted shortlist and create your observation plan, using the online Web Application.
• Prepare your equipment well in advance before the observing night and always take dark, bias and flat calibration frames before and after your observation.
• At least 10 dark frames should be taken with stable CCD/CMOS temperature. The exposure time should be the same with that of the light frames and all frames should be taken at the same temperature with the light exposures.
• At least 10 bias frames should be taken with stable CCD/CMOS temperature. There is no exposure time for bias frame but make sure that all frames should be taken at the very same temperature with the light exposures.
• At least 10 flat frames should be taken under a uniform illumination. Exposure time should be very small (depending on your uniform illumination). Make sure that nothing has been changed in your optical setup between flat and light frames. Camera orientation, telescope focus and temperature should remain the same during the entire observing run.
• The observation run is prefered to be performed unfiltered (clear aperture). It is significant to observe the target in the same field during the night. In this way, it is easier to apply differential photometry with a single standard star from the field. Make sure that you include bright but not saturated stars in the surrounding field. In order to identify the target in the starfield, you can use the AstFinder tool. Try not do observe the asteroids among dense stellar fields, in order to distiguish the target and perform uninterrupted photometry.
• Each observation run is required to be at least 4 hours in duration each night. This also depends on the rotation period and the observability of the asteroid from your location. The longer the light curves, the better results we get.
• After the data acquisition, follow the instructions below and SUBMIT your observations through our server.

Sample Light Curves

A sample of light curves are listed below, so as to give an idea of the results we expect to extract out of our observational campaign.

The phase diagram of 7132 Casulli during the 2020 apparition.

The phase diagram of 2768 Gorky (1972 RX3) from Sopot Astronomical Observatory in Serbia during the 2019 apparition.

The phase diagram of 2768 Gorky (1972 RX3) from UOAO in Greece during the 2019 apparition.

The phase diagram of 2839 Annette (1929 TP) from Altimira Observatory in California/USA during the 2007 apparition.

The phase diagram of 2839 Annette (1929 TP) from UOAO in Greece during the 2020 apparition.

Additional Information

All targets for the project are displayed in the List of Primordial Family members. In order you to find which of these asteroids are observable during your observation period from your location, we are highly recommend to use the online  Web Application  The application will also provide the observation plan for your selected target. The ephemerides of asteroids can be also calculated through MPC Ephemeris Service or JPL's HORIZON system.

Further Reading

• http://www.minorplanet.info/ObsGuides/Misc/photometryguide.htm Minor Planet Website
• "A Practial Guide to Lightcurve Photometry and Analysis", Warner B.D., 2006, Springer
• "The Backyard Astronomer's Guide". Dickinson T. and Alan D., Firefly Books, 2008
• "Confessions of a Beginner Asteroid Light Curve Photometrist", Menke J., Society for Astronomical Sciences Annual Symposium, Vol. 22, 2003 (ADS link)

Data Collection

Observations are accepted from professional and amateur astronomers, who actively collaborate with University of Athens faculty members and wish to be partners in Ancient Asteroids Project.

Electronic submission of the observations is required. This involves uploading your image and calibration files in .fits (.fits, .fts or .fits), following the instructions given below.

Applicants are required to consult the relevant "Observing Guidelines" webpage when preparing their observation plan. Usually, an observation plan includes several hours of data collection with specific requirements, that all observers should follow, in order to produce useful data in our project. Make sure to follow all instructions given below and use the provided online tools for contacting us and for praparing your observation plan. These are required to proper refer to you as a collaborator and use your data in our project. Not following the exact steps may cause your files to be lost, not properly processed and eventually not used in the project.

Personal Information

In order to submit your observations, we first need to know a few things about you. We kindly ask you to fill the online PERSONAL INFORMATION FORM. Instructions for filling the Personal Information Form can be found here.

Data Preparation

• Name your files using the date of the observing night in the following format (YYMMDD) and add your first and last name (e.g. 210201_Kosmas_Gazeas.zip for an observing run on 1st February 2021).
• If you submit multiple different observing sets within a single night, use numbers to differentiate (e.g. 210101_Kosmas_Gazeas_1.zip, 210101_Kosmas_Gazeas_2.zip).
• Do not submit the same data set under a different name.
• Keep names to less than 30 characters and do not use special characters or spaces in the filenames.
• If you submit your files and find that you need to make a change, submit the revised files with the same name and add a version number. This will overwrite your previous submission, which will be used in the final processing.

Data Submission

Please upload your data through the online DATA SUBMISSION FORM. Instructions for filling the Data Submission Form can be found here.

Your contribution, personal information and data files will be received by the members of the Data Processing and Analysis Consortium (DPAC). The observations will be evaluated and will be further proccessed, in order to be included for analysis.