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4.   Small Telescope Science Program

The Small Telescope Science Program (STSP) was established in early 2000 to provide baseline information about the target comet and to complement scientific data acquired at large, professional telescopes. The STSP is a network of advanced amateur, student, and professional astronomers who use small telescopes, often less than 1.0 meter, equipped with charged-coupled devices (CCDs) to make continuous, scientifically meaningful observations of comet 9P/Tempel 1. This pioneering effort to engage advanced observers continues for several months after encounter in July 2005.

Since 1999, the science team has been conducting a vigorous program of ground based observations of Tempel 1 to characterize the nucleus and the dust environment. The science team wants to learn as much as possible about the comet before impact, including:

  • Volatile outgassing
  • Dust coma development and dust production rates
  • Dust tail development
  • Jet activity and outbursts

These characteristics vary as the comet moves along its orbit and can be used as long-term baselines to describe the activity of the comet with respect to time. However, observers have limited access to large telescopes, and thus the baselines usually have sparse data points.

Advanced amateurs with discretionary telescope time and private observatories can perform valuable, long-term and continuous monitoring of Tempel 1 to help fill gaps in the baselines. Often the smaller telescopes used by these observers are fast, have large fields of view and are well suited for acquiring data on these variable characteristics of the comet.

The program re-launches in late 2004 when Tempel 1 returns to the inner solar system and becomes favorable for observing. The 2004-2005 observing campaign straddles Deep Impact's encounter with comet Tempel 1 on July 4, 2005. We are asking STSP observers from around the world to monitor the comet as often as possible. In particular, we are looking for several types of observations:

  • Broadband-RI CCD images and photometry for the duration of the campaign:
    Pre-impact data will help us fill gaps in the pre-impact (baseline) dust production light curve. Post-impact data will be compared to the baseline to help us understand how the impact effected the dust activity of Tempel 1.
  • Broadband-VRI CCD images from March 2005 through August 2005 to search for jet activity:
    During the 1983 apparition, Tempel 1 appeared to have at least two jets during the months before perihelion. As the comet approaches perihelion in July 2005, we want to monitor for jet activity. Also, the impact is expected to make a new active area on the nucleus and may cause new jets or outbursts days or weeks later.
  • Broadband-VR and unfiltered images, in wide format, to look for interactions of the dust tail with the solar magnetic field.
  • Any narrowband photometry and spectroscopy that STSP observers provide will be accepted; these types of data are within the capabilities of some advanced amateur astronomers.

For information about observing campaigns, procedures, etc for the STSP, please visit the STSP website at

You have the information, now it's just a matter of practicing. Go out and observe!

Updated: 10-Dec-2018