The Astrophysical Observatory at CSI -- (C.U.N.Y.) is known Internationally as I. A. U. Station #294


Asteroid Hazard Research
Overview of the NEO Problem

Since the realization that Asteroids and Comets pose a hazard to planet Earth a number of observatories under the guidance of the International Astronomical Union (I.A.U.) Minor Planet Commission have been  hunting for new objects that come near the Earth, collectively called, NEO's, (Near Earth Objects) or specifically when referring to Asteroids, NEA's (Near Earth Asteroids). Current thinking is that if an Asteroid is detected to be capable of hitting the earth many years or even decades from now, then we can do something about it. Like, for example, rendezvous with the "killer" asteroid and change it's course. Perhaps, if it is of economic value, like a pure Nickel Iron, or spent comet, composition then we might guide the offending object to the moon for future mining to recover the monies spent on moving it and then some. For extensive additional informational resources please see the section below entitled,  "NEO Information"  Comets are of two types, in terms of defense, short period, which theoretically, as with asteroids, we might muster a defense. Long period comets usually discovered within 2 or 3 months before a close approach, at this time, there is no defense. Our best defense is a space program for all possibilities is a space program. If we have space craft capable of reaching a dangerous NEO whose trajectory has Earth as a target, we can change its trajectory by various interceptor ways.
 

As the famous Arthur C Clarke 
  "The dinosaurs became extinct because they didn't have a space program ,  and if we become extinct because we don't have a space program, it'll serve us right!"

NEO Research Objective

 The research objective at the observatory is to find and track Asteroids and occasional Comets. The hunting of targets, known and unknown, is done by taking several images with  Charge Coupled Device Cameras (C.C.D.). The C.C.D. digital cameras are cooled electronically to, in some cases, to 50 degrees below ambient temperature to increase sensitivity to the dim images we are hunting. Via software one can align multiple images with common stars and then rapidly flash all images in sequence. This latter process is known as "blinking" and the stars in the flashing matched images will not move but any object in the solar system will be seen jumping between it's changing positions. This blinking technique helps us identify Asteroids in the star field we are taking images of.  As a general rule,  the closer the Asteroid to the Earth, then the brighter is it's image.  Also, the greater the "jump" in the blinking process, since it's angular motion would be faster when near us. Targets are obtained from a variety of sources. If you are interested in the details of  how to hunt and track Asteroids see the section below "Resources for Asteroid Hunters"!

NEO Research  Measurements

 Once the target is identified software permits us to calculate the positions of every object on an image. We use the celestial coordinates, Right Ascension (RA) and Declination (Dec) to pin-point target position. Once we have a proper scale for the image, we can measure the position  of the object to within one second of arc accuracy. As a general rule, when we submitted data, in the early days, on NEOs taken at our observatory, we were about 90 % on target accuracy of less than 1 sec of arc. Inherent in these measurements is the fact that our computer clocks were updated via the Naval Observatory Clocks every five minutes so that our images were time stamped and our measurements were accurate to within one second of time. These precise readings were collected into a report that is sent to the IAU's Minor Planet Center located at Harvard. The positional data (the whole process is called Astrometry )is used to help calculate or update the orbital parameters that determine the orbit about the Sun. Hence, we help keep accurate track of these potentially dangerous objects that can create extreme environmental disruptions of the biosphere by colliding with our planet. For details on the use of the data see the section below" Resources for Asteroid Hunters."

Our Research Efforts

Today the research program at the observatory has expanded from using our 16" telescope to using remote dark site observatories with much larger aperture telescopes  to obtain images of even dimmer targets  in our quest to find and measures Asteroids and Comets. We have many years of images from the Tenagra Observatory located in southern Arizona. Recently, the success of our and others at this observatory in this endeavor, has led to NASA taking over all the telescopes there as a follow up to NEOs. We are expanding our remote observing program to observatories in Spain, New Mexico, California and Australia. In general, one has to pay for time on telescopes and we have had support monies from NSF, NASA and private donations to do so. 

NEO Information

The overall problem and the some of the latest information is provided by Ron Baalke, Near-Earth Object Webmaster NASA's Near Earth Object Program Office  Pasadena, California  

This site is a definitive site for the entire field with extensive links to the world wide effort., including NASA, ESA and observatory efforts dedicated to the problem.  Check the site out at Near Earth Objects 

For example: Lots of  overall Details at this site at link: Near Earth Object Introduction etc.     see also  European space guard site 

Resources for Asteroid Hunters

Resources for Asteroid Hunters

The Basic idea:

      Overall coordination of the world wide effort is found at the  IAU Minor Planet Center. This center establishes the guidelines for undertaking Astrometry known as the Guide to Minor Body Astrometry. Here you will find resources on Astrometry software and techniques, as well as , how to report your findings.  Suggest products if you are going to do Astrometry at your own observatory. We have used products from " Software Bisque". Their  combination of  "CCDsoft" (older control software no longer being supported)  to run our Cameras and "The Sky" to control our computerized Meade 16"  LX 200 Telescope had given us a very user friendly systems so that Undergraduate students can join Our Research Group and assists us in this effort.  We still use the latest version of "The SKY" to plan our runs when we are hunting for unknowns at our remote sites.  We also used and still use for our remote work  Astrometricahttp://www.astrometrica.at/ which is excellent for blinking, finding asteroids and its "track and stack" is worth learning because it will increase your ability to get faster and dimming targets!

     Essentially, you need  a or access to a  telescope equipped with a CCD camera (all today use these), a good computer and serious dedication to this undertaking.

Additional Software Resources:

Time Keeping software: 

We have used  the "Tardis" time synchronization software in our Windows based computers very successfully when we did work locally. "Tardis" can be found at many sites on the web. Use a search engine, such as, "www.google.com" to locate and install the software. See also Guide to Minor Body Astrometry for suggestions 

Obtaining Targets to Track: The need for observations to better establish orbits of already discovered NEOs or Minor Planets(MP)   in general 

    Once you establish yourself as a official IAU observatory, you will need targets to track. The secret of a good nights run is to plan ahead. There are a number of targets that are needed and you should look over the following places to obtain targets. As a general rule, our list  below gives ordered priority to the MPC NEO confirmation  targets, the MPC's monthly critical list, then either the European NeoDys priority targets as well as the Lowell Observatory targets. If you join the recommend Minor Planet Mailing List (see below) you will be able to be informed as to what is happening currently, as well as,  occasionally, get other interesting targets to track.  

1.   MPC NEO Confirmationhttp://minorplanetcenter.net//iau/NEO/toconfirm_tabular.html page   Once you select an object a predicted position (an ephemeride) of the target per hour on a given day can be generated for your observatory.

2.  Orbital Elements: https://minorplanetcenter.net//iau/Ephemerides/SoftwareEls.htmlMPC Critical-List Minor Planets this link is for obtaining the elements in the form to load into popular planetarium-type software packages.

For example: we use the "Sky" and it and other software permits you to directly load the above within the software if you are connected to the web. Hence, you have access to know  where the targets are via your software to help plan your evenings run.

3. Check out the "Priority List" first and Menu of Opportunities last at the ESA European Space Agency Priority list via this site and the  MPC can be used to generate an ephemerides of the targets.

4. Obtain targets from monthly "Critical lists" from the Lowell Observatories Asteroid Services and other important Asteroid info there.

5. Lots of bright targets are located at FUAP http://asteroidi.uai.it/en/fuap(followup astrometric Program site).

Do I have a new Discovery?: 

When tracking known objects you will find that many times, depending on the field of view of your system, additional targets show up in blinking. Hence, it is important to know what other asteroids are in the area of  your image. Your software should be able to plot all known asteroids in either the  "MPC's "MPCORB" Data base  ( Astrometrica does this very well)

Also available is the  Lowell observatory's  ASTORB data base of all known Asteroids.

Minor Planet Mailing List  :

We strongly advise joining the Minor Planet Mailing List. which is now a Yahoo group.  

Evaluating your Results: 

The European NEODys site keeps track of all NEA's, as well as observatories  doing the work and specific information on the quality of measurements. For example, statistics measured at  our observatory when active from 1997 to 2005 Ie.   IAU 294-Astrophysical Observatory at the College of Staten Island. The details found here, optical NEA measured at IAU #294,  is invaluable for us to know how effective were  the various techniques we were using. Today our work is scattered amongst the many remote sites we use.  The MPC also keeps general statistics on observatories and how well they are doing approaching the suggested accuracy of positions to less than one second of arc at The MPC Residual page. Knowing when   Improvement is needed  when ones residuals get large is good science.!