Main Page

Observations are ongoing for 13B discoveries! Check the Survey Overview for our progress in getting & processing photons.

Upcoming

• Feb-June 2014: CFHT provides additional astrometry for 13A discoveries.
• August 2014: All OSSOS imaging on 13A targets will have been acquired.

Data Releases

Collaboration Data Releases

The Teams will receive the object list for each semester's discoveries as a summary table of internal designations with orbital elements and uncertainties. At release, a typical object will have a semimajor axis uncertainty of 0.1-1%. Dynamical classification using the SSBN 2008 classification will be provided. Core will also provide access to the full astrometry and the imaging data for each detection.

Some topic teams will then wish to propose observations to other telescopes for next-semester studies of the sample; this will likely be the only time when the topic teams have a proposal advantage over the world. The ephemerides of most objects at the time of proposal will be good to +/- <1 arcmin; the half-year-later CFHT recovery of all objects will have dropped these uncertainties to a few arcseconds by the time P.I.-led exploitation observations occur.

• 2013AE data release (access restricted to collaboration only)

MPC codes used in flagging astrometry

Public data releases

We aim to submit all observations of a given semester to the MPC 6 months after the end of the semesters; e.g. for 2013A, an MPC submission at the end of January 2014. This gives observers on quarterly systems a chance to propose for telescope deadlines a cycle later with no competition. It also gives the theory teams 5 months to work before the world sees the MPC release. Recovery observations will be sent as a batch to the MPC in the same manner, e.g. an MPC submission in August 2014 for the Feb-July 2014 recoveries of the 2013 detections.

• August 1, 2014: 2013A CFHT imaging becomes public to the world.

Field Layout

2013A

• OSSOS April 2013 preliminary field layout plot (here for reference. As in the proposal; varied very slightly from the observed location)
• OSSOS April 2013 observed plot - as the O and E fields have oppositions a month apart, the E field is shown at its 9 April moon-dark location, and the O field at its 8 May moon-dark location. The known TNOs plotted are for new moon, May 9.
  • 13AE discoveries plot - all positions for 9 April 2013

2013B

• OSSOS October 2013 field layout plot. The field positions and known TNO locations at October 2013 new moon (4 October).

The project will be surveying two sets of fields, spring and fall. For great detail, see the OSSOSurveyDraft and the Accepted Proposal (access restricted).

In each season a 7x3 block of fields will be positioned near the ecliptic plane and a second group of fields will be positioned off the plane. Each set of fields will be observed repeatedly through-out the semester (a few nights per dark run for 5 dark runs centered on the April/May dark runs for the on/off ecliptic fields). These fields will then be re-observed in 2014A to obtain a high-precision orbits on all KBOs detected in the field. The discovery triplet (near opposition) is the crucial portion, because this is the only place where the magnitude performance will be measured; tracking of objects with detection magnitudes brighter than the 40% efficiency should be >95%.

In addition to deep imaging done to discover and track the TNOs, a heavily-overlapping set of shallower imaging (grey boxes in the layout figure) will allow an extremely precise internal astrometric (and relative photometric) solution in each patch, tied to Sloan. Based on a pathfinder project, this yields orbits of 0.1-1% semimajor axis uncertainty inside the first 5 months, and a factor of 10-30 better by the end of the second year. (RMS residuals are 30-50 milli-arcseconds for bright targets, and 80-100 for fainter ones).

OSSOS will go deeper than previous 4-meter class surveys due to both operations in queue mode and (after mid 2013) the expected IQ improvement provided by CFHT's dome venting (which will lower the median IQ from the current 0.72" to the range 0.6-0.65"). With an expected 40% detection efficiency at r-band magnitude 24.4-24.5, in the ecliptic OSSOS will yield something like 3-4 objects per square degree, with about half that sky density for the off-ecliptic fields.

Topic Teams

How to join OSSOS

The OSSOS project is divided into topic-teams that are each responsible for ensuring that a particular aspect of the survey science is fully exploited. At the start of the survey each member of the project has elected to participate in one or two topic teams, based on their science interests as stated at the start of the survey. By joining a topic team the science team member is committing to helping the Team in this area of science exploitation. Each team selects one of the team members to be the Team Leader who will act as the principle information conduit back to the survey and is responsible for keeping the topic team focused, organized, and sharing information so that progress is made.

 Team members MUST have a precise well-defined role for what they are committed to do in that Topic Team,
 and agree to openly collaborate with other members of that Topic Team who share similar interests.
 The OSSOS collaborational agreement (to be electronically signed early April 2013 to get access to the data flow) 
 must be accepted by each OSSOS collaborator that wishes access to the target list and OSSOS Survey Simulator 
 before the world release.

OSSOS collaboration, alphabetical listing

Full list of OSSOS collaborators is available.

Core Team

Core

Observation acquisition, moving object detection, orbit linkage, characterization

The OSSOS LP proposal is available on the Core Team's page.

Alphabetical Topic Team list

Binaries

mutual orbits, separation, colours. Leader: A. Parker.

Cometary Activity

Search for coma. Leader: P. Rousselot.

Light curves

Time variable TNOs, phase curves. Leader: S. Benecchi.

Catalogs

Objects slower than OSSOS rate cut) + non-moving object variation (eg. variable stars). Leader: L. Jones.

Nearby objects

Search for and tracking of objects moving faster than OSSOS cuts (roughly, inside 8 AU). SUSPENDED.

Occultations

Predictions, observing campaigns. Leader: W. Fraser.

Resonant Populations

relative populations, libration amplitude distributions. Leader: R. Murray-Clay.

Scattering

Centaurs, Scattering Disk, Oort cloud connection. Leader: N. Kaib

Classical Belt, structure and SDF

H-mag distributions, dependence on class. ABSORBED INTO CORE: Petit as leader.

Surfaces

Colours, NIR spectra. Leader: A. Delsanti.

Thermal Modeling

Thermal evolution of objects. Leader: A. Guilbert

Publications and Proposals

Survey and Team logos for use in presentations etc (high-res PNGs). The font is (free!) Sofia Pro Light. Download it here.

Publications and Proposals should be entered on this link.

Principle Contacts

At the current time, the principle contact for each team member should be their Topic Team's Team Leader. Team Leader's can contact any of the three core-team members:

Brett Gladman

JJ Kavelaars

Jean-Marc Petit

Timeline and Upcoming Deadlines

• June 6/2012: OSSOS was number 1 ranked CFHT Large program. 560hr awarded.

• Feb. 2013 - Aug 2013 : 2013A data acquisition.
• Aug 2013 - late Jan 2014 : 2013B data acquisition.

• Oct 6/2013: Second OSSOS team meeting, at 2013 DPS meeting in Denver.

Help

Consult the User's Guide for information on using the wiki software.