Washington ? The National Aeronautics and Space Administration is taking a step toward possible robotic servicing of the aging Hubble Space Telescope by formally requesting proposals to help do the job.

The request was put out Tuesday with the intent of allowing NASA to award initial contracts by October if it decides to proceed, according to Edward Weiler, the agency’s associate administrator for space science.

In January, NASA Administrator Sean O’Keefe, citing safety issues raised by last year’s Columbia accident, decided not to allow any more servicing of the Hubble by shuttles.

Weiler said NASA officials, having received 26 replies to a recent request for ideas on use of robotics, are becoming more confident the approach can substitute for part, and perhaps all, of a canceled shuttle servicing mission, which would have been the fifth since Hubble was carried aloft by a shuttle in 1990.

NASA is asking initially for proposals to build a propulsion module that would be part of a larger vehicle outfitted to service the Hubble robotically. The propulsion module ultimately would be used to guide the telescope to a controlled re-entry or other safe disposal, such as boosting it to a much higher orbit, at the end of its life.

NASA also is asking for proposals to build a stand-alone vehicle for use solely for end-of-life disposal of the telescope. Responses for both scenarios are due by July 16.