Kowalski has had a lifelong interest in astronomy with an emphasis on planetary science. As an amateur in Florida during the 1990s he developed an interest in astrometric and photometric observations of asteroids. He started the Minor Planet Mailing List in mid-1997. Kowalski discovered 14627 Emilkowalski in 1998.
In 1999 he was invited to use the Jet Propulsion Laboratory's 0.6-m Ritchey-Chrétien telescope to make observations in support of the Deep Space 1 mission. Also in 1999 he was the Scientific Coordinator for the first Minor Planet Amateur-Professional Workshop at Lowell Observatory in Flagstaff, Arizona.
He has been a member of the Catalina Sky Survey (CSS) in Tucson, Arizona since September, 2005 and has discovered hundreds of Near Earth and main belt asteroids along with six comets. Of these, periodic comet 226P/Pigott-LINEAR-Kowalski was the recovery of Edward Pigott's lost comet of 1783.
On October 6, 2008, while observing with the CSS 1.5 meter (60") telescope at the peak of Mount Lemmon, he discovered 2008 TC3. Approximately 20 hours after its discovery this asteroid entered the Earth's atmosphere over Sudan, becoming the first asteroid discovered before impact with the earth. Kowalski was honored with a small piece of 2008 TC3.
- Richard Kowalski (21 July 2008). "10 Years of the Minor Planet Mailing List". Minor Planet Mailing List. Retrieved 2009-12-22.
- D. Nesvorný, D. Vokrouhlický (2006). "New Candidates for Recent Asteroid Breakups". Astronomical Journal 132 (5): 1950–1958. Bibcode:2006Aj....132.1950N. doi:10.1086/507989.
- Paul G. Comba (ed.) (1999). "Proceedings of the 1999 Minor Planet Amateur/Professional Workshop". 1999 Minor Planet Amateur/Professional Workshop. Proceedings. Bibcode:1999mpap.work.....C.
- Steve Chesley, Paul Chodas, Don Yeomans (4 November 2008). "Asteroid 2008 TC3 Strikes Earth: Predictions and Observations Agree". NASA/JPL. Retrieved 2009-12-22.
- Richard Kowalski (21 September 2009). "2008 TC3 to Almahatta Sitta and back to Tucson". Minor Planet Mailing List. Retrieved 2009-12-22.
- NASA (3 January 2014). "The First Discovered Asteroid of 2014 Collides With The Earth - An Update".
- Kelly Beatty - Sky & Telescope (3 January 2014). "Small Asteroid 2014 AA Hits Earth".
- "7392 Kowalski (1984 EX)". JPL Small-Body Database Browser. NASA/JPL. Retrieved 2009-12-22.