Their orbits are very different. Hubble is at about 20 degree inclination, and the ISS is about 60 degrees. The delta v needed to change 40 degrees of inclination is more than half the orbital speed, which means that would take more than 4 km/sec of delta v. Then another similar delta v to return it.

We have known that Hubble was eventually doomed, but NASA and Congress have not been eager to prepare another rescue attempt in advance of this event, even with the possibility of borrowing the mysterious X-37B (or is the Air Force unwilling to lend it out?). I think that we have to acknowledge and accept the sad fact that Hubble will eventually or soon be relegated to reduced-science mode, at least for the foreseeable future.

But I do not think the Hubble has available hard points that are robotically accessible.

But maybe a simple clamp on system could be assembled inside a year? Or at least something to boost it to a higher orbit to save it for latter repairs.

Richard: WFIRST stands for Wide Field Infrared Space Telescope. It is not designed to provide optical observations. It, like Webb, is not a replacement for Hubble in the slightest.

wayne: I’ve said this before, but it simply isn’t that good a lecture on my part. Too long. Better people read the book.

(this should have a lot more Views!)

born01930: My rough memory is that Dragon and Starliner are only rated for about a week in orbit, unattached to ISS.

They are not designed to do this, and making it possible is far harder than you imagine. In fact, right now a robotic mission to Hubble might make more sense. Some NASA engineers proposed this back in the mid-2000s, when then-NASA administrator Sean O’Keefe canceled the last shuttle servicing mission. Then it didn’t make sense, as the technology and engineering was not far enough advanced. Today such a mission is very conceivable, at a reasonable cost.

Maybe it is a pipe dream but it seems like an adapter node for the Dragon (ala Apollo-Soyuz) that can take a vacuum, have handholds and a small grappler could be built. I am no rocket engineer which is obvious…the hardest part may be the environmental control for Dragon. Do you know how long it is supposed to be rated for staying aloft?

Diane Wilson: The problem with ground-based telescopes using adaptive optics is that they can only observe very small fields sharply. With Hubble gone we will no longer have its wide field capabilities.

Moreover, except for Keck all the giant ground-based telescopes built in the past two decades have had serious technical problems, unexpected by their designers or builders, and have thus produced disappointing results. (I have written about his for Sky & Telescope: see their January 2015 issue.)

The simple fact is that it is much more cost effective for astronomers to build an optical space telescope. They get much more bang for the buck. We are losing this now.

Best of all, these can be serviced from the ground.