Quantifying the value of a set of NEO observations is necessarily subjective, but NEOfixer provides a framework within which to explore this idea. NEOfixer estimates the value of obtaining new observations of any NEO, from any site, for all time (in the near future). That same calculus can be turned around to examine what was the actual benefit, now that the observations are in hand. We can start by taking the discovery tracklet of any NEO and progressively fit orbits, adding one tracklet at a time, while estimating the sky-plane uncertainty at the time and place of the next tracklet. This gives a proxy measurement for each tracklet’s Benefit to the orbit, which can be weighted by the object’s Importance to planetary defense. NEOfixer provides Benefit Plots under each object page, which illustrate this method of estimating the benefit of historical NEO observations.
One advantage of this technique is that it can be done for any object, provided the time of submission to the MPC is known (observations that languished for hours or days between observation and submission may end up providing little to no benefit to an orbit, if observations taken later were incorporated sooner).
By tallying the value of all observations, and dividing them into useful categories (e.g. all observations by a given MPC code, or within a certain time period, or from NEOfixer users before and after adopting NEOfixer), we can measure whether the community is spending its observing time efficiently, and identify specific sites or classes of objects representing potential areas for improvement.