Observational activities of ESA's NEO telescope network on fast-moving objects

ESA's Planetary Defence Office operates a network of telescopes with a nearly-global worldwide distribution, with the specific task of responding in near real-time to observing alerts triggered by the discovery of new threatening near-Earth objects.

The network is routinely used to observe very fast-moving targets, such as NEOs during extreme close approaches or imminent impactors. In such cases, the observational circumstances often resemble those of artificial objects in distant Earth orbit, and therefore most of the challenges are also close analogs to those common during SST observations.

Our team has also organized specific campaigns targeting artificial objects in high orbits, and those in unbound orbits during launches or fly-bys. These observations provide us with the ideal testing grounds for our techniques, since they closely replicate the observational peculiarities of a nearby NEO while providing a "ground truth" against which the results can be compared.

In this contribution we will present some of these observational challenges, and how we address them with our observatories and telescopes, with the hope of triggering a fruitful discussion and exchange of strategies between the NEO and the SST communities.