SpaceX Pushes for Operating Starlinks Below ISS

SpaceX's second-generation Starlink satellites are proving more robust than expected and can operate easily a couple of hundred kilometers lower than their 525-535 km operational orbits without hardware changes, the company told the FCC Space Bureau last week. It said its pending request for operating in the 340-360 km range capitalizes "on the significant space sustainability and service improvements that lower-altitude operations allow." SpaceX said it has been coordinating with NASA and the National Science Foundation to ensure that the lower-altitude operations won't increase risk to federal space and science missions and in many cases will decrease risk. Earlier this month, the bureau posed a series of questions to SpaceX about its lower-altitude plans. Pointing to its partial approval of the company's second-generation constellation (see 2212010052), including a condition that it not deploy satellites that operate below the International Space Station -- roughly 400 km altitude --, the agency asked how many satellites SpaceX anticipates operating below the ISS at any one time. In its filing last week, SpaceX said the figure could vary, but potentially 600, though perhaps more. It said it hopes ultimately the FCC will sign off on 19,440 satellites at 340-360 km altitudes, as it requested in its second-generation application. However, for now it wants to include those orbital shells as an option for its first tranche of 7,500 second-gen satellites. SpaceX said its automated collision avoidance system "has proven its mettle on-orbit."