This Week’s Spotlight: Calipatria, CA

The RECON network is made of over 55 communities on the Western United States ranging from Washington to Arizona, made of teachers, students, volunteers, and countless community members who are enthusiastic about science. This year, we are going to be featuring our communities so that we can get to know the unique cities and people that are part of the RECON network.

Calipatria, CA

This week’s feature is Calipatria, CA! This community joined us in November 2014 and is made up of teachers and students from the Astronomy Club at Calipatria High School led by Keitha McCandless. Check out Calipatria’s Facebook profile to learn more about them!



To explore the full list of RECON communities, visit our communities page. 

If your community is interested in creating a profile either on social media or through the RECON website, email us at

This Week’s Spotlight: Quincy, CA

The RECON network is made of over 55 communities on the Western United States ranging from Washington to Arizona, made of teachers, students, volunteers, and countless community members who are enthusiastic about science. This year, we are going to be feautiring our communities so that we can get to know the unique cities and people that are part of the RECON network.

Quincy, CA

This week’s feature is Quincy, CA. Quincy has been part of the RECON project since the start of our pilot project in Fall 2012. Charles Arrowsmith teaches astronomy at Feather River Community College and leads the Quincy RECON team. Students and teachers from both the college and Quincy High School are involved, and the Quincy site was featured in a ScienceNation Video about the project. The Quincy team maintains an active RECON page on their Google+ site. Check it out to learn more about this community!


To explore the full list of RECON communities, visit our communities page. 

If your community is interested in creating a profile either on social media or through the RECON website, email us at

What’s in a name?

Our next RECON event this coming Monday evening involves Centaur 12CG!  A challenging component of this event is that the target will be rising low in the eastern sky. Note that this won’t give our teams a ton of time to lock on the star field.

We wanted to take this opportunity to talk for a second about the naming convention for TNOs and other minor planets.  For all of our previous events, you may have noticed that objects had names like 14UT114 and 08FC76, while our event this week does not have a number at the end. Let’s break this down.

The name 12CG indicates that this object was the seventh minor planet discovered in the two week period between February 1 – February 15, 2012.  The first two digits (12) represent the year of discovery and the first letter (C) indicates the half-month of discovery. The letter A is for objects discovered between January 1-15, B is for January 16-31, and C for February 1-15. Note that the letter “I” is skipped, resulting in Y representing the 24th half-month of December 16-31. The second character (G) is the order of discover, with A being the first object in that period and G being the seventh. Here again, the letter “I” is not used, so this naming convention can be used for the first 25 objects discovered in a given half-month.

So why do most TNOs end with a number while 12CG does not? After the 25 object discovered in a half month,a number is indexed at the end of the name and second alpha character cycles back through the alphabet. Thus, while the 25th discovered object between February 1 – February 15 would be 12CZ, the 26th object would be named 12CA1, and the 27th would be 12CB1.

Ready to quiz yourself? Try 14UT114:

  • 14U = Object was discovered between October 16-31, 2014
  • T114 = We’ve cycled 114 times through the 25 letters of the alphabet (minus the letter “I”), or 114 x 25 = 2,850 times. The letter T indicates it is the 19th object after these 2,850 prior objects. So the object is the 2,869th discovery of this half-month.

How about 08FC76? . . . yup, the 1,903rd minor discovered between March 16-31, 2008. For more information and clarification, check out the following Wikipage on provisional designation in astronomy.

Good luck to all of our teams this Monday evening!!!

Happy Winter Solstice, 2016!

On this Winter Solstice, the RECON Team wanted to wish all a happy holiday season!!!

RECON Team Meeting in Carson City, August 2016

RECON Team Meeting in Carson City, August 2016

We are extremely grateful to all of our RECON students, teachers, amateur astronomers and community members who have contributed to this year’s activities.  Below is a quick RECON Year in Review!

All together, we attempted 8 full network campaigns, set up essential data infrastructure for RECON campaigns, and published 2 manuscripts in The Astronomical Journal. With most video files now uploaded into the RECON database, we are currently busy analyzing video from the above events as we prepare for our upcoming January 2017 campaigns.

In addition to our team meeting in Nevada, John had the pleasure of visiting sites in Oregon, Northern California, Owens Valley, and along the Colorado River while Marc visited sites in both Washington and Arizona. We also has a new team join from Wildwood School in Los Angeles. Throughout all of our interactions, we continue to be impressed by the dedication and enthusiasm of our RECON communities!

Wishing you the warmest of holidays!!!

John, Marc, Ilianna, Diana, Matthew, Audrey, and Jeralyn


Reading RECON Event Detail Page

As RECON prepares for our our upcoming campaign early Wednesday morning this week, we thought we would take this opportunity to point out some of the interesting information found on the Event Detail Page for each RECON event.

For our upcoming event, teams should print out both of the following important webpages:

Event Overview:

The Event Detail Page for every campaign starts with useful information characterizing the event.


This introductory section provides lots of cool details:

  • An object named (281371) 08FC76 is going to occult a star named UC4-565-008609.
  • The predicted shadow reaches the point closest to Earth’s center at 11:55:36 Universal Time on November 23, 2016.
  • We provide J2000 coordinates (the RA and DEC of the target star back in 2000) and equinox of date coordinates (the RA and DEC for the star today). Note that the coordinates are close but not exactly the same because Earth is slow precessing (or wobbling) on its axis. Our CPC-1100 telescopes use equinox of date coordinates.
  • The target star is faint — magnitude of 14.6 using a Red (R) filter — but about 100x brighter than the TNO — magnitude 19.3 using a Visible (V) filter). Every 5 orders of magnitude is 100 times fainter. RECON setups can measure down to about magnitude 16, which means our sites will be able to record the star but will record no signal when the fainter TNO is passes in front of it —fingers crossed!
  • The waning crescent Moon should not be an issue for this campaign.  It is only 29% illuminated and reasonably far away (115 degrees) from the target.
  • For our upcoming event, the centerline passes directly over the RECON network. Click the link on the page for a detailed RECON map of the network.
  • To the right of the globe are details about the position, motion, size, and dynamical classification of the TNO. In this case, we are dealing with a Centaur which, at 10.6 AU, is currently just outside the orbit of Saturn. Note that we don’t know the actual albedo, or reflectivity, of the Centaur — that’s another thing we will be able to determine if we measure the object’s size.
  • The 1-sigma uncertainty in time for the event is 47 seconds and the cross-track uncertainty is 595 km. This means that there is a 68% chance that the prediction times listed are good to within 47 seconds, and a 68% chance that the shadow will land within 595 km of the centerline shown. This is why we need so many telescopes and need to record video lasting longer than a few minutes.

Star Training Set:

Event_Detail_Page_StartrainingNext, we provide teams with a star training set. This is a list of 5-6 stars, in addition to the target star, that can be used to provide an indication of how accurately the telescope is aligned and in what direction. You’ll notice that the magnitudes of the stars listed are going from brightest (mag 0.8) to dimmest (mag 14.6), and that the separation between the star and the target is getting smaller (from 11.52 degrees down to 0.24 degrees). By pointing the telescope at each object, the team can get a sense of where the target is likely to appear in the camera field of view when they use the final coordinates for TNO (281371) 08FC76.

Star Chart:

Following this, an automatically generated star chart shows nearby stars along with a green rectangle representing the RECON camera field of view. Note that we are still tweaking how this star chart displays, and for now the star chart provided on the Event Page is a better depiction of the star field at the actual time of the event.

Site Table:

Finally, we provide a table listing all of our RECON sites along with useful information unique to each location. Among other information, the text just above the table provides an indication of the median spacing of the RECON network for this event (26.8 km) and the probability of success assuming clear skies (67.1%). These REALLY good odds for TNO occultation astronomy are only made possible by our awesome network of team members spanning a baseline of roughly 1,700 km. The probability takes into account the uncertainty in the position of the TNO and the target star, the estimated size of the object, and the median spacing of telescopes across the network.


For each RECON site, you can read off the following information:

  • For all of our sites the Sun is down (negative altitude), the sky is dark, and the Moon is up.
  • The position of the star (star altitude and azimuth) is provided for each site. 10 degrees corresponds to a fist held at arms length. Due north is 0 degrees azimuth, 90 degrees is east, 180 degrees is south, and 270 degrees is west. For Oroville during the event time, the star will be 34.8 degrees above the horizon (about three and a half fists) and in the direction of 265 degrees, or just 5 degrees south of due west.
  • Remember the 1-sigma cross track error of 595 km above?  For each site the table lists how far the site is from the centerline prediction. Note that all RECON sites south of Madras/Culver (X-track = 569 km) are within the 1-sigma zone.

All times on the page are in Universal Time (UT) and need to be converted to local time. Our teams on Pacific Standard Time (PST) are 8 hours behind UT, and our teams on Mountain Standard Time (MST) are 7 hours behind UT. Let’s take a look at three examples:

  • The recording window for Oroville is 11:47:21-11:56:15 UT (see above). Because they are on Pacific Time, our Oroville team will subtract 8 hours and record from 03:47:21-03:56:15 PST.
  • The recording window for Yuma Arizona is 11:46:54-11:55:48 UT (see below). Because Yuma (and all of Arizona) are on Mountain Time, our team there will subtract 7 hours and record from 04:46:54-04:55:48 MST.
  • Our team in Laughlin/Bullhead City, with a start time of 11:46:56 UT, is in the funkiest situation (see below).  If the team observes from Laughlin, Nevada, they will start recording at 03:46:56 PST; if they are in Bullhead City, Arizona, they will start recording at 04:46:56 MST.  Both are the same Universal Time which is why astronomers prefer to use UT rather than local time!


J2000 Star Training Set (NOT for standard RECON Setups):

The final table provided on the Event Detail page is the same star training set using J2000 coordinates. Some of our volunteer sties are using scopes that use J2000 coordinates, unlike our RECON Celestron scopes. Standard RECON sites should use the star training table at the top of the page above the star chart!

RECON Prediction System at Work

As with all science, RECON is a work in progress, and we will continue to refine our predication and observation planning tools. All of the above useful information is available for each occultation prediction found on the Global TNO Event Candidate List and RECON TNO Event Watchlist. Each of these lists is updated weekly and provides predictions looking two years into the future – including our next RECON event after this week involving Centaur 14UT114 on 11 December, 2016 UT.

Best TNO Opportunity Yet!

During the week of Thanksgiving, the RECON community is looking forward to the best TNO occultation opportunity since the start of our full network last year!  On Wednesday morning, November 23, around 3:55AM Pacific (4:55AM Mountain), Centaur 08FC76 will be occulting 14.6 magnitude star UC4-565-008609 in the constellation Taurus.

Prediction map for 08FC76

Prediction map for 08FC76

This event is EXACTLY the type of campaign that RECON was designed to pursue.  As shown on the map here, the predicted centerline for the occultation shadow passes directly through the center of our network! Recently kicked into an orbit neighboring Saturn, Centaur 08FC76 will be only 9.6 AU from Earth. Based on how well we know the orbit for this object, the 1-sigma cross-track uncertainty in the shadow path prediction is only 595 km. Importantly, this places every RECON telescope site from Madras, Oregon to Idyllwild, California within this zone of high probability for detection. That’s 43 of our 60 communities!!! Based upon our calculations, there is at least a 67% probability that RECON will capture this event, more than double any of our previous events.

And, as with all RECON events, each telescope site is crucial for mapping out the region of space around this TNO. Does this Centaur have a smaller moon . . . or moons?  Does it have rings? How big is it actually? How bright is it? What is its shape? We plan to address all of these questions and more through data collected during this upcoming holiday campaign!

Marc has also taken the extra step of incorporating recent data from the Gaia Mission in to the prediction above. With the additional precision provided on the position of the target star, the prediction path has remained in the center of the network. This makes for an even stronger prediction that the shadow of this Centaur will passing over our network on the morning of November 23. This is the highest probability event we have had since the start of the project!

For more information on this event, visit the Event Page and Event Detail Page for 08FC76. RECON Teams are asked to sign up for the event using the RECON Campaign Signup Form. We are extremely thankful to all of our RECON team members for supporting this upcoming campaign and for all of the preparation and dedication that has gotten us to this point.

Clear skies … south of Kingman

During our event last weekend, cloudy skies and rain impacted most all of our Washington, Oregon, California, and Nevada sites.  The clouds parted south of Kingman and at least five communities along the Colorado River collected data along with pockets in Lee Vining, Searchlight, and elsewhere.  We will be analyzing these video files in the coming week.  For a snapshot of how things went for each of our telescope sites, you can check out an Event Summary for 12UT68.

Teams that have not yet submitted a RECON Campaign Observation Report Form for the event have until this Sunday evening (one week following the event) to complete this dataset. Also, stay tuned for our next event on the Wednesday morning before Thanksgiving. This is going to be our best TNO occultation opportunity since the start of the RECON Project!