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!

Ready despite the clouds!

It’s been four months since our last campaign, but RECON is prepped and ready for our first full network campaign of the 2016-17 school year!

12UT68 Prediction Map

Predicted shadow centerline for 12UT68

Tonight’s event involves Centaur 12UT68. Formed out beyond Neptune, this object was recently kicked inward to the solar neighborhood near Saturn and Neptune. Estimates place its size at 30-75 km, but RECON is trying to determine this with far greater precision. Although the predicted shadow path is slightly off the network, the 1-sigma uncertainty in this prediction is 600 km. This means there is a good chance the shadow may pass over communities to the south, and all of our scopes are well positioned to probe the region around 12UT68.

As with all ground-based astronomy, weather and sky conditions are always an important factor. As of this morning, the weather is not looking great for many of our teams in the Northwest and spotty for several Northern California and Nevada teams. The sky cover prediction map below was produced using tools available at

Cloud cover prediction for 12UT68 event (Copyright 2016 A.Danko)

Cloud cover prediction for 12UT68 event (Copyright 2016 A.Danko)

For our teams with partly cloudy skies, they will be aligning their telescopes and finding the star field using patches of clear sky. Then it will be a matter of waiting it out to see if the target region of northeastern sky stays clear during the 20-minute observing window just after 11:10PM PDT/MST tonight. And hopefully the prediction for better weather will hold for our teams in southern California and along the Colorado River closest to the shadow centerline prediction!

For more details on this event, visit our Event Page for 12UT68. Good luck to all of our teams able to observe tonight despite less than ideal weather! Also, stay tuned for our next event on the morning of Wednesday, November 23, with a predicted shadow passing directly through the center of the RECON network!!!

Details on Main Belt Asteroid Patientia

Below are details for an optional main belt asteroid campaign for RECON teams from Lake Havasu to Yuma.  For more details, refer to Occult Watcher and following link:

Date: 05 October 2016 UT
Recording Window: 06:06:00 – 06:09:00
Sense-up: x2

Star training set for 451 Patientia, (2016/10/05 06:08UT)
Object RA Dec mag sep mel
Fomalhaut 22:58:34.4 -29:31:59 1.2 3.75 96
PPM 274650 23:10:38.8 -27:59:51 5.9 0.76 100
PPM 274716 23:14:12.4 -28:19:26 8.3 0.39 100
451 Patientia 23:14:04.0 -27:56:21 9.2 100
Positions are for equinox of date


Starchart for Patientia provided by Steve Preston

Starchart for Patientia provided by Steve Preston


Starfield for Patientia provided by John Keller at 128x

Starfield for Patientia provided by John Keller at 128x

For any of you needing the J2000 coordinates, here is your list:

J2000 Star training set for 451 Patientia
Object RA Dec mag sep mel
Fomalhaut 22:57:39.5 -29:37:23 1.2 3.75 96
PPM 274650 23:09:44.7 -28:05:19 5.9 0.76 100
PPM 274716 23:13:18.5 -28:24:55 8.3 0.39 100
451 Patientia 23:13:10.1 -28:01:50 9.2 100
Positions are for J2000


Occultation of TYC 5780-01169-1 by (19) Fortuna

On 2016, August 13 at 06:30 UT, main belt asteroid (19) Fortuna occulted the star TYC 5780-01169-1 in the constellation Aquarius. Four RECON teams and two other observers recorded the event. A total of five teams actually observed an occultation and one team observed a miss. Observing a miss can be just as important as observing an occultation because misses help define the size of the asteroid. For a more comprehensive overview about the data analysis process for main belt asteroid occultations, see Tony George’s blog post from January, 2016.

Here is the path for the event, which passed over the northern part of the RECON network. Even if you don’t have access to the Occult Watcher program, occultation announcements and maps such as this can be found at the asteroid occultation website.

Map of 19 Fortuna's shadow path

Map of 19 Fortuna’s shadow path

Here are light curves from the three RECON teams that recorded an occultation. Note that the horizontal and vertical scales on each of these light curves are different.

Manson light curve of 19 Fortuna

RECON Manson, Jared Mumley

Ellensburg light curve of 19 Fortuna

RECON Ellensburg, Megan Rivard and Bruce Palmquist

The Dalles light curve of 19 Fortuna

RECON The Dalles, Bryan Dean

Occultation scientists, such as every member of RECON, can use these light curves to determine the disappearance and reappearance time of the occulted star. IOTA, the International Occultation Timing Association, uses these disappearance and reappearance times, along with the location of the observers to estimate the outline of the asteroid.

Each of the chords in the plot below shows when and where the target star is visible. When the asteroid occults the star, there is a gap in the cord equivalent to the amount of time the star disappeared. When all of the chords and gaps are combined, you can start to see the size and shape of the asteroid. The gray area shows a model of the asteroid’s shape based on existing data. Notice how chord 1 fits the model almost exactly while chord 4, measured by RECON Ellensburg, starts and stops inside the predicted shape of the asteroid model. This could indicate a slight error in Ellensburg’s timing. But it could also mean that the actual shape of the asteroid is a little narrower along that line than predicted. Less likely but still possible, there are deep indentations in those portions of the asteroid. Chord 7, measured by RECON The Dalles, has a very small gap indicating that just the tip of the asteroid occulted the star.

Shape of 19 Fortuna according to current models

Click on the image above for a higher resolution view of the plot.

Main belt asteroid occultations are a great way to train new RECON participants in occultation science. One of the main reasons for this is that you can often see the target star and the asteroid. So even if your site does not record an occultation, you can still observe the dynamic nature of the Solar System by watching the asteroid move towards and then away from the target star.

Credits: We give a big “Thank You” to Tony George for generating and extracting precise timing information from our light curves.

Gaia Billion-Star 3D Map of Galaxy

This past week, the European Space Agency released its first dataset produced by the Gaia Mission, a spacecraft in orbit around the Earth-Sun second Lagrange point (L2). This dataset provides precise position and brightness information for over 1.1 billion stars in the Milky Way and satellite galaxies, along with distances and proper motions for 2 million of these. With still more data to come, Gaia provides the most comprehensive 3-dimensional map of the stars in our galaxy.

First release of Gaia dataset (ESA)

First release of Gaia dataset (ESA)

The release of this dataset is extremely significant to RECON, as it essentially eliminates previous uncertainties in the positional information of occultation target stars. This will allow us to make more precise predictions of occultation paths for trans-Neptunian Objects (TNOs). Uncertainties remain in our measurements of TNO positions, but Gaia provides a significant improvement to our occultation prediction efforts.

RECON Team Meeting Rocked!

Thanks to the 70 team representatives – included 10 students – who joined us in Carson City back in August for our first annual RECON Team Meeting! The meeting was a very productive opportunity to reconnect, review recent publications, and prepare for future research campaigns. For copies of presentations and materials, visit our Presentations and Educational Resources Page. Below is a group photo from the event:

RECON Team Meeting, Carson City, 2016

RECON Team Meeting, Carson City, 2016

We  also discussed plans for our next team meeting, which will likely be held mid- to late-October 2017 up in the Pacific Northwest!

RECON Team Meeting August 3-5

RECON is gearing up for its first annual Team Meeting to be held in Carson City, Nevada, August 3-5. This science team meeting is an opportunity for representatives from all of our community teams to come together to talk about recent science results, upcoming campaigns, and procedural updates on the project.

More information on the RECON Team Meeting Webpage. Team representatives should use the REGISTER NOW link on that page to sign up for the meeting.

Summer RECON Events

As RECON rolls into the summer months, Marc has been busy doing follow-up observations to provide up-to-date predictions for three upcoming summer TNO occultation events. Based upon this recent work, we are currently planning the following official and optional campaigns:

OFFICIAL FULL CAMPAIGN – 08JO41 on June 20 around 08:48 UT

With an estimated size of 50-125 km, Scattered Disc Object 08JO41 is exactly the type of trans-Neptunian Object that the RECON Network was designed to measure. Based upon astrometry collected this past week, the predicted centerline for this event is over southern Oregon with a 1-sigma cross-track uncertainty of 1511 km.

Global prediction map for 08JO41

Global prediction map for 08JO41

Map showing predicted centerline for 08JO41 (with uncertainty of 1511 km)

Map showing predicted centerline for 08JO41 (with uncertainty of 1511 km)

Based upon our uncertainty calculations, there is a 30% chance that the shadow will pass over a portion of the network. And as with all full campaigns, all telescope sites from Yuma to Oroville provide important data to probe the regions around 08JO41 for moons and rings. Thanks to all RECON teams for gearing up for this full campaign event.


With a diameter of around 1110 km, Classical Kuiper Belt Object Quaoar is roughly half the size of Pluto and has a small moon named Weywot.

An artist's conception of Quaoar and its small moon Weywot. Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech) - See more at:

An artist’s conception of Quaoar and its small moon Weywot.
Credit: NASA/JPL-Caltech/R. Hurt (SSC-Caltech)
– See more at:


There are two upcoming close approaches that could bring the shadow path of this large KBO over the RECON network. The first is on June 26 UT and the next is on July 23 UT. If the object does pass over the network, multiple telescope sites would record this occultation. Marc and several other observers are conducting on-going observations to pin down the probabilities of success for RECON on these two dates (which are currently at 3.2% and 1.4%, respectively). However, there is something peculiar about how this recent data is matching up with previously collected orbital data. Given this, we are announcing these events as optional campaigns for the network and encouraging all RECON teams that are available to participate. We will provide weekly updates leading up to these events, so stay tuned.