According to recent news reports, Urthecast is planning to launch a satellite constellation of optical and SAR satellites by the end of the decade. Urthecast started its space business by installing Earth observation cameras on the ISS. If this constellation comes through, it will be the first commercial private SAR + optical constellation. Exciting times ahead for remote sensing, especially for radar imaging. One wonders how the general public will feel about the SAR imagery, because right now they can pretty much understand what optical imagery is showing them, as long as they stick to true color imagery. How they will feel about the “colorless” gray-scale intensity SAR imagery remains to be seen. Of course, with the possibilities of nearly concurrent optical and SAR imagery, the applications are endless, starting with the through-cloud and day-night capability of SAR imagery to support optical imagery.
The proposed constellation is expected to comprise 16 satellites (8 optical and 8 SAR) flying in two orbital planes, with each plane consisting of four satellite pairs, equally-spaced around the orbit plane. Each pair of satellites will consist of a dual-mode, high-resolution optical satellite (both imagery and video) and a dual-frequency (X-band and L-band) SAR satellite (X-band and L-band) flying in tandem.
P. S. Here is a non-related but interesting article about the kind of business prospects Urthecast is stepping into.