PARIS — Satellite fleet operator AsiaSat of Hong Kong on Dec. 16 said it is returning to Space Systems/Loral (SSL) for the construction of the AsiaSat 9 C-, Ku- and Ka-band satellite under a contract that leaves open, for three months, the possibility of adding a weather sensor to the satellite’s payload.

Under the contract, valued at $163.6 million, SSL will deliver AsiaSat 9 within 31 months. AsiaSat has 120 days from the contract signing to determine whether a 300-kilogram hyperspectral weather sensor, to be provided by GeoMetWatch (GMW) of Las Vegas, will be part of the payload. The sensor is expected to require 500 watts of power.

AsiaSat agreed to fly the sensor, called STORM-1, pending resolution of financial and technical details that included GMW’s issuance of a convertible note to AsiaSat for a value to be determined by the two companies.

A July 31 deadline for closing the deal was extended by mutual agreement of AsiaSat and GMW. In its Dec. 16 filing with the Hong Kong Stock Exchange, AsiaSat said it has the option of asking SSL to integrate the GMW sensor at any time up to 120 days after the contract signing.

AsiaSat 9 will replace the AsiaSat 4 satellite at 122 degrees east, with a launch — likely on an International Launch Services Proton rocket — scheduled for mid-2016.

Palo Alto, Calif.-based SSL, a subsidiary of Canada’s MDA Corp., is already building the AsiaSat 6 and AsiaSat 8 satellites, both of which are scheduled for launch in the first half of 2014.

Peter B. de Selding was the Paris bureau chief for SpaceNews.