Lightcurves

PRIMARY RESEARCH

Starting in 2010, the main goal of The Red Barn Observatory is to determine the rotational periods of newly detected Near Earth Objects, Potentially Hazardous Asteroids, and other Minor Planets in need of studies.  Astrometry from these objects is also determined and reported to the Minor Planet Center.

The primary reason for studying the rotational periods of these objects is to determine their structural composites.  Theoretically, an asteroid, such as a solid metallic or stony asteroid would possibly have a faster rotational period than that of a "rubble pile" asteroid - a "rubble pile" meaning an object that has developed over a period of time from smaller meteoroid pieces or created from a larger body that has been impacted and reformed.  These rubble pile asteroids can only rotate so fast, or the centrifugal force would overcome gravity and cause them to simply "fly apart".  This points out that since the metallic asteroids will not "fly apart" they are capable of spinning faster.  The purpose for studying these objects is to give us a better idea as to how we could attack the object if we were to discover a potential impactor.

LIGHTCURVES & PHOTOMETRY OF MINOR PLANETS

Obtaining lightcurves or photometry from minor planets is an art of its own!  To quickly define what a lightcurve or what photometry of minor planets is - "the variation of the magnitude of light reflected to Earth, measured with some form of "light gathering tool" (usually a telescope & CCD), and measuring this variation.  Imagine looking at a someone holding an egg 20 feet away from you.  If they hold it upright, you can see it pretty good.  If they point the egg at you, its not as easy to see.  This is because of the amount of light the egg is reflecting.  Most asteroids, normally much larger than an egg but somewhat shaped like a potato, rotate in space.  When these "spuds" rotate, the amount of light reflected from the asteroid can be collected and compared over a period of time.  Once a certain amount of data collected is combined, a lightcurve can be generated.  By doing this, the rotation can be determined, whether it is a binary system (two or more asteroids rotating each other), and a rough estimate of the shape of the asteroid can be determined with enough data and the proper software.

The lightcurve or photometry that I collect from minor planets will be documented on this web page.  I will use my own equipment (0.3-meter SCT and SBIG ST-7 CCD) along with several other telescopes via the Tzec Maun Observatories in Australia and New Mexico.  Use of these telescopes will create a more accurate lightcurve.  If anyone is interested in publishing your lightcurve work here on this page, or interested in sharing data to refine my or your lightcurves - please contact me at sefarmer[at]cometary[dot]net.

The following Minor Planets are only a few of the ones that I have worked on.  I have now decided to document them as fully as possible and this will be done within this page.  Clicking on the object name will take you to the objects main page containing more information.

 

NEO 2010 NR1

Structural Composition:  Monolithic

http://www.minorplanetcenter.org/mpec/K10/K10N46.html

 

PHA 2002 FB3

Structural Composition:  Monolithic

Published - http://www.minorplanetcenter.org/mpec/K10/K10F46.html

Published at Tzec Maun Foundation - http://blog.tzecmaun.org/?p=992

 

321 Florentina

Structural Composition:  Monolithic

Published at Tzec Maun Foundation - http://blog.tzecmaun.org/?p=992

 

NEO 2006 WO127

Structural Composition:  Questionable -  Monolithic or Rubble Pile Asteroid (RPA)

Published - http://www.minorplanetcenter.org/mpec/K10/K10G45.html

Published - http://www.minorplanetcenter.org/mpec/K10/K10G01.html

Published - http://www.minorplanetcenter.org/mpec/K10/K10FA0.html

Published - Tzec Maun Foundation - http://blog.tzecmaun.org/?p=992

 

Asteroid 210 Isabella

Structural Composition:  Questionable - more data needed


The following objects are in a preliminary state and the lightcurves are from only one observation session.  I processed the one nights data and went ahead and posted this information here to be updated.  The Minor Planet Center Lightcurve Parameters page http://www.cfa.harvard.edu/iau/lists/LightcurveDat.html shows Asteroid 444 to have a rotational period of 6.214 hours.

Asteroid 444 Gyptis

444_Gyptis.PNG (31369 bytes)

Preliminary version of Asteroid 444 Gyptis from one nights observations.  The second night of observations of this object were not obtainable due to clouds.  More observations are planned for this object as well as a few others for a complete and accurate lightcurve.

Asteroid 521 Brixia


521_Brixia.PNG (28838 bytes)

Information will be updated as it is collected.  This asteroid supposedly has a rotational period of more than 24 hours.


The following minor planet lightcurves were produced by Axel Martin:

 

- 350 Ornamenta (2010-04-10 until 2010-04-21)

- 674 Rachele (2010-02-12 until 2010-03-23)

- 776 Berbericia (2010-02-12 until 2010-04-09)

 

In addition to the 12"-Newtonian at #628 (Mulheim-Ruhr) the FSQ-105, the 7"-APO and the 16"-RC at H10 (New Mexico Skies) were used to collect the data.

The lightcurves can be found under:

 

- Ornamenta:

http://obswww.unige.ch/~behrend/page1cou.html#000350

http://markt.bph.rub.de/~axelm/tso/lichtkurven.htm#350_ornamenta_2010

 

- Rachele:

http://obswww.unige.ch/~behrend/page2cou.html#000674

http://markt.bph.rub.de/~axelm/tso/lichtkurven.htm#674_rachele

 

- Berbericia:

http://obswww.unige.ch/~behrend/page3cou.html#000776

http://markt.bph.rub.de/~axelm/tso/lichtkurven.htm#776_berbericia

 

- 129 Antigone (2010-05-19 until 2010-05-26)

- 185 Eunike (2010-04-21 until 2010-05-22)

In addition to the 12"-Newtonian at #628 (Mulheim-Ruhr) the 7"-APO and the 16"-RC at H10 (New Mexico Skies) were used to collect the data.

The lightcurves can be found under:

- Antigone:

http://obswww.unige.ch/~behrend/page1cou.html#000129

http://markt.bph.rub.de/~axelm/tso/lichtkurven.htm#129_antigone

- Eunike:

http://obswww.unige.ch/~behrend/page1cou.html#000185

http://markt.bph.rub.de/~axelm/tso/lichtkurven.htm#185_eunike