CS3 News and Events

The 28-inch Ritchey-Chretien Gets a Home
December 18, 2016

While the mount is still being refurbished, it was moved into the observatory. Testing and configuration will continue
through the winter.
Probable Binary Asteroid Found

While reobserving a Hungaria asteroid to confirm previous results, Bob Stephens noticed some unusual activity observing
(24465) 2000 SX155. Petr Parvec confirmed that the asteroid is almost certainly a binary with a 2.66087 hour primary period,
a 9.252 eclipse and occultation period, and possibly a 6.2847 hour third period.
DPS-ESPC Meeting
October 16 - 21, 2016
Pasadena, California

Brian Warner and Bob Stephens attended the combined Division of Planetary Sciences/European Planetary Science Congress
meeting in Pasadena. Brian and Bob were co-authors of an oral talk given by Professor Linda French on their latest results on
Jovian Trojan asteroids. They also presented a poster paper on their work on very wide binary asteroids. 
Binaries 4 Asteroid Workshop
June 21 - 24, 2016
Prague, Czech Republic

Brian Warner and Bob Stephens traveled to the Binaries 4 workshop in Prague where about 40 of the leading experts in
binary asteroids gathered to discuss the latest findings for these multiple body systems. Brian gave a talk titled "Some
(Apparently) Very Wide Binaries" discussion the latest findings at CS3. After the workshop, Bob traveled to Germany to
tour the Nördlinger-Ries and Steinham craters which are thought to have been created when a binary asteroid hit the
Earth about 15 million years ago.
Back to Cerro Tololo Inter-American Observatory
April 20 - May 10, 2016

Bob Stephens and Linda French had a 15-night observing run. The first 5 nights was on the 4-meter Blanco Telescope
and the next 10 nights on the 0.9-meter SMARTS telescopes. Persistent clouds reduced the amount of data they could
collect on Jovian Trojan asteroids.

Near Earth Asteroid (53110) 1999 AR7 found to be a binary
December 31, 2015
From observations between December 19 and 31, 2015, Brian Warner found that the Near Earth Asteroid (53110) 1999 AR7
has a satellite with an orbital period of 31.31 hours. The primary asteroid rotates once every 2.7375 hours. (53110) 1999 AR7
was discovered on January 11, 1999 by the LINEAR survey program around orbits the sun once every 2.11 years.
New Binary Asteroid Discovery
November 19, 2015

Robert Stephens and Brian Warner announced their discovery of a satellite of the main-belt asteroid 5425 Vojtech
in the Central Bureau for Astronomical Telegrams No. 4200. The asteroid's primary rotational period is 2.64759 hours
and the satellite has an orbital period of 25.43 hours.
28-Inch Telescope Donation
A 28-inch (0.7-meter) telescope has been donated to the Center for Solar System Studies. An observatory is under construction and it should be operational in 2016. The additional capabilities of this telescope will be useful for studying small Near Earth asteroids and dim Trojan asteroids. In this picture, the split-ring mount is shown next to Dan Coley (left) and Bob Stephens (right).
New Solar Energy System
September 24, 2015

We finished installing and commissioning a solar energy system. This DIY project was needed because during the summer,
the air conditioning need to keep the electronics and optics cool in the eight observatories were keeping us firmly in Tier 4
for half the year. The system is rated for 5.4 kWh at the height of summer. At the start of summer, we were generating
4.7 kWh.
Bob Stephens Using the 4-meter at Cerro Tololo Inter-American Observatory
May 30  - June 15, 2015

Bob Stephens and Linda French had consecutive runs on the 4-meter and 0.9-meter telescopes at Cerro Tololo Inter-American
Observatory in Chile. They had 15 nights observing Jovian Trojan asteroids. 
Daniel Coley Awarded Shoemaker Grant
April 17, 2015
Dan Coley was one of 6 winners of the 2015 Planetary Society Shoemaker NEO Grants. He received funding to purchase a Finger Lakes Microline CCD camera with a ST-1001e chip to assist in his asteroid studies. The large chip on this camera will increase the Field of View on his 14-inch Meade to over 20 arcminutes, which will allow him to follow Near Earth Asteroids longer before switching fields.
Bob Stephens and Alson Wong Observer the Total Lunar Eclipse from CS3
April 4, 2015

A Total Lunar Eclipse occurred at dawn.
John Hoot and Tom Mathis Observatories Under Construction
March 29, 2015

The roofs for the two new observatories are under construction, and the observatories should be operational by summer.
Bob Stephens and Alson Wong Catch the Total Solar Eclipse Over the North Atlantic
March 20, 2015

Bob Stephens and Alson Wong were on board a chartered flight to see the eclipse over the Faroe Islands, between Iceland and Scotland.
Division of Planetary Sciences Meeting
November 9-14, 2014

Brian Warner and Bob Stephens attended the American Astronomical Society's Division of Planetary Sciences meeting in Tucson,
Arizona. Bob presented a poster paper on their work on Near-Earth Asteroids while Brian gave an oral talk on his Hungaria program.
Total Lunar Eclipse
October 8, 2014
A Total Lunar Eclipse occurred on the morning of October 8, 2014. Starting at 3:35 AM PDT, it lasted for just over an hour.
Grading on New Observatory Pads
Spetember 27, 2014
Grading occurred on a new row of observatory pads. Three observatories could be built in this area, although only two are scheduled for construction. An observatory with telescopes to be operated by John Hoot will be in the northeast corner. Behind it to the south will be an observatory with a telescope owned by Tom Mathis.
Planetary Conjunction
August 23, 2014

Although not really breaking science - a nice conjunction of the crescent Moon, Jupiter and Venus occurred on August 23, 2014.
Asteroids, Comets, Meteors (ACM) Conference - Helsinki, Finland
July 13, 2014

Brian Warner and Bob Stephens attended the ACM Conference in Helsinki Finland. This conference is held once every three years in
different locations. Brian and Bob presented two poster papers which included Dan on Near Earth Asteroids and Hungaria Asteroids.
Bob also presented a paper by Linda French on Trojan Asteroids. While there, Brian and Bob visited the Helsinki Observatory for the
opening reception. Bob later went with part of the ACM group for a hike in a nearby forest.
Eleven Night Observing Run at Cerro Tololo Inter-American Observatory
May 10, 2014

Bob Stephens, Linda French and Jennifer Seiben had a 10 night observing run starting in late April 2014. They got an additional night
when they found that nobody was was scheduled to use the telescope on the day they arrived. This video shows some of the steps
involved in operating the 0.9-meter telescope at CTIO.
Lunar Eclipse - April 15, 2014
The Total Lunar Eclipse was observed from the Center for Solar System Studies by Bob Stephens and Alson Wong. Here is a close-up using a 6" F/4 telescope and a wide-angle picture from within one of the observatories.
Observing Run at Cerro Tololo Inter-American Observatory
October 11, 2013

Bob Stephens, Linda French and Chelsea Davitt used the 0.9-meter telescope at Cerro Tololo to observe Trojan asteroids. Below is a
time-lapse of southern skies.
First Light for 20-inch

The 20-inch Ritchey-Chretien telescope has been moved from Brian Warner's former observatory in Colorado to CS3. Polar Alignment has been completed and the first images of a Near-Earth asteroid were obtained on September 25.


The 20-inch observatory is the last of the first phase of observatories. There are now ten operating telescopes and one more awaiting refurbishment and activation.

CS3 Receives Observatory Codes
August 28, 2013

The Minor Planet Center has assigned observatory codes to some of the CS3 telescopes. Bob Stephens' telescopes were assigned code U81 and Brian Warner's telescopes were assigned code U82.
CS3 Supports Radar Observations from Goldstone Deep Space Network
August 16, 2013
Lightcurves of the near-Earth asteroid 2005 WK4 obtained by Bob Stephens from CS3 assisted the astronomers at Goldstone in getting high resolution radar images. This collage of radar images was obtained on August 8, 2013 and shows the asteroid is between 660 - 980 feet in diameter.

The Planetary Society Blog

August 6, 2013

CS3 was highlighted in Bruce Betts' blog about results generated from the recent Shoemaker NEO grants.


Determining Near Earth Asteroid Properties from the California Desert

Wong Observatory Roof Installed

June 8, 2013


The roof was installed on Alson's Wong Observatory. The telescope is scheduled to be moved at the end of June. Five of the six

observatories are functional. Alson Wong's observatory is bottom left, Bob Stephens' lower right. Dan Coley's observatory is middle

right. Brian Warner has all of the other observatories included the incomplete one in the back row.

Observing at Lowell Observatory

May 28, 2013


Linda French and Bob Stephens used the 42-inch Hall telescope at Lowell Observatory to observe two Near-earth asteroids.


Warner Telescopes Arrive

May 18, 2013


Brian Warner installed 4 of his 5 telescopes in two observatories at CS3. As of the end of May, the three Meade 14-inch LX200's and

the 12-inch LX200 were being operated remotely and robotically.

New AllSky Camera and Weather Station

January 20, 2013


An Orion AllSky Camera II and a Davis Instruments Vantage Pro II Weather Station has been installed at CS3. See the weather tab

for images or weather information updated every few minutes.

Ground Broken for New Observatories

January 14, 2013


Concrete has been poured on four new observatories which will eventually contain seven new telescopes.

Open House at CS3

December 1, 2012

To celebrate the completion of the new facilities at CS3, a Star Party and Open House was held for people in the Landers Community.

CS3 Expansion

November 24, 2012

A major expansion was completed on the main house at CS3 adding two bedrooms and a bathroom.

New Electricial Service

October 31, 2012

With the assistance of a grant from Edison International, the electrical service at CS3 was upgraded to 400 amps allowing for the

installation of several future observatories.

Observing Trojan Asteroids at Cerro Tololo Inter-American Observatory in Chile

October 4, 2012

Last month Bob Stephens made his fourth trip to Cerro Tololo to observe Trojan asteroids using the 0.9-meter telescope.

First Light on New Observatory

July 22, 2012

The 16-inch and 14-inch telescopes have been moved to the first observatory. While still undergoing testing and configuration, the 16-inch was used to get observations of 205 Martha, which helped resolved its rotational period to be 14.912 hours plus or minus about 30 seconds. This was a particularly difficult case. 205 Martha has been observed many times in the past, usually for only a couple nights. Previous results ranged from 9 to 39 hours. Like for this opposition, most of those lightcurves showed a very small amplitude (difference from brightest to dimmest observation). When a small amplitude is present, then the object might be nearly spheroid, or perhaps the rotational pole is pointed towards Earth. In either case, surface features or albedo differences can cause the lightcurve to be almost anything. It is not necessarily in the shape of a sine wave. Only by examining small repeating details in the lightcurve and experimenting with harmonic orders in the Fourier analysis can one possible period be deemed to be superior to another.

Ralph Megna Talk at Seattle Astronomical Society

January 22, 2012

Observatory Construction

January 22, 2012

Progress is being made on constructing the first observatory at CS3. Over the past few weekends, concrete was poured for the piers

and two observatory slabs.

Total Lunar Eclipse

December 10, 2011

A Total Lunar Eclipse was viewed at Dawn from CS3.

Grading at CS3

October 23, 2011

The property at CS3 was graded preparing for construction of the observatories.

A Tale of Two Observatories

October 18, 2011


Bob Stephens and Brian Warner went to the EPSC-DPS planetary science meeing in Nantes, France to present papers on their

asteroid work. Later they toured obervatories in Paris and London, in addition to other stops along the way.

Observing Trojan Asteroids with the CTIO 4-meter Blanco Telescope

August 29, 2011

A compiliation of Bob Stephens joined Linda French and Larry Wasserman two observing runs at Cerro Tololo Inter-American

Observatory in Chile observing Jovian Trojan asteroids. Bob and Linda used the 0.9-meter in July 2011. They were joined by

Larry Wasserman in August to use the 4-meter Blanco Telescope.  The video is available in HD 1080p.

Pirate Painting Party

June 18, 2011


In early June with the assistance of friends of CS3, the Control Room / Workshop (aka 1000 sqft. garage) was painted.  This might

have been the first time it was painted since 1988.

Society for Astronomical Sciences Symposium

June 6, 2011

Bob Stephens, Ralph Megna and Dan Coley attended the Symposium on Telescope Sciences in late May 2011.  Details can be found

at the SAS web site (http://socastrosci.org/symposium.html).  Bob Stephens and Brian Warner were interviewed by Bob Naeye

of Sky & Telescope, who posted the interview on their YouTube account.

Observing at Lowell Observatory

May 22, 2011

In early May 2011, Bob Stephens along with Linda French used the 72-inch Perkins Telescope at Lowell Observatory's Anderson Mesa

Station to observe a Trojan asteroid and a Near Earth Asteroid.  Below is a 2 minute video of the telescope in its dome.  The mount

was originally build in 1931 and moved to Arizona in 1969.  It is jointly operated with Boston University.