Where Are The New Hubbles?

An interesting and little known fact I came across while doing my research for the Portal Authority series got my attention.

The Hubble Space Telescope is dying. No, that isn’t the little known fact. That fact has been widely heralded, as has the brilliant legacy of good science and incredible images it has given the world over its 20 year history.

At this writing, NASA has been able to resolve the latest problem with the Hubble and it is back on line, though for how long is a good question.

The Hubble’s designated successor, the Crown Prince to the aging King, is the James Webb Space Telescope, JWST. Time on it will certainly be a treasure beyond price. Perhaps 20% of proposals for time on the Hubble actually pass muster. The number for the JWST will likely be lower.

The JWST is billions over budget ($10 billion US at this writing) and has had many delays. Unlike the Hubble, it is a specialist, concentrating on the infrared spectrum. NASA has gone to great lengths to make it as sensitive as possible, with sophisticated sunshades and sensors cooled to ultra-low temperatures. All this bleeding edge exoplanet-focused stuff comes at a high cost in money, time and effort.

Whether the JWST is worth it is a question I’m not qualified to comment on. When it is finally up and operational it will carry with it many hopes for new discoveries and many dreams of great breakthroughs in our understanding of the universe. The elusive question to whether we are alone in the Universe might even be within our grasp.

The JWST will be a unique and irreplaceable asset. There are many hazards which could befall it, from a failure of the launch vehicle to an unforeseen technical problem to something no one ever thought of, despite all the testing and checking. NASA has gone to extraordinary lengths to ensure no such disaster befalls its multi – billion dollar baby, but what they don’t have is a backup in case the unthinkable happens.

A second JWST just isn’t fiscally possible. The cost of one is causing NASA’S budget, and likely its political support for said budget, to creak noticeably under the strain. Even if the money was there, building it would take years the agency wouldn’t have in the wake of a high-profile failure.

So now we get to the little known fact. In 2012 the US National Reconnaissance Office, the agency which builds, launches and maintains the US military satellite network, made NASA a gift of two large satellite telescopes, with 2.4 metre mirrors, the same size as the Hubble, free for nothing.

There has been little public attention paid to this rather unusual gift, and while NASA is mulling over what to do with them, they sit in a clean room.

The building of the Hubble was an epic in its time, quite as much as the JWST today, and the cost not much less, about 9.5 billion dollars in today’s money. Uniquely, it was designed to be refurbished and upgraded by successive Shuttle missions, and so it was. All of this was very costly. The Shuttle’s promise of cheap and regular access to space turned out to be expensive, and very limited.

Given that the telescopes are in hand at no cost, what would it take to build and launch Hubble follow-ons?

The Hubble is quoted at an all up mass of 24,500 lb., or 11,136 kg. We might reasonably assume the Hubble follow-ons could at least match that, given two decades and more of improvement in computer technology, materials and space based technology generally.

First, then, we need a launch vehicle. It’s not a space telescope until it’s in space, after all.

These days, the number to call for cheap reliable spacelift is SpaceX. The Falcon 9 can put 22,800 kg into LEO. The cost is 50 million dollars, give or take. That leaves plenty of margin for weight growth, with possibly a transit stage to boost the telescope into a higher orbit. One of the limitations the Hubble users deal with every day is the fact that in LEO the Earth occupies a big chunk of the sky.

A fundamental design decision which would need to be made early on would be whether the Hubble follow-ons would be repairable and upgradable on orbit as the Hubble was. The four Shuttle servicing missions to the Hubble are undoubtedly the reason it is still operating today, or for that matter ever fulfilled its potential at all after the disaster of the error in grinding the primary mirror.

The Shuttle, of course, is one with Nineveh and Tyre. Crew Dragon makes regular runs to the ISS, and Boeing’s Starliner will be in service as soon as the bugs are out of it.There are other companies in the game, too. One could reasonably expect to be able to put such a contract on the street a few years down the road and have multiple bidders for it. Such a mission would likely be far cheaper than the estimated $1.5 billion for a Shuttle launch, but would likely still be pricy.

Or, there is the more conventional ‘launch it and operate it until it dies’ mission profile. With the payload margin discussed above, there would be room for plenty of consumables in addition to a transit stage.

The Kepler telescope lasted for over 9 years before it was deactivated, and its mission ended because it ran out of fuel. A non-refurbishable scope in a heliocentric Kepler-type orbit might approach the life of the Hubble with enough consumables, and have a much more productive observation schedule.

The Kepler, to be sure, was a one-trick pony. It had one, count it, one instrument. A Hubble follow-on would require a much more capable suite of instruments.

Bleeding edge instruments built new would be costly, both in terms of time and money. There could be a scrounge, though. The legacy of the Hubble servicing missions is a collection of flight-proven instruments which did good service in their time, and were replaced only because they were surpassed by newer ones.

It would probably be necessary to pry them from the clutching fingers of their current owners and refurbish them, but it would save quite a bit of time and money.

All told, one might reasonably budget a billion for such a telescope and get it into the bag without too much trouble.

Such scopes would not be the bleeding edge king of the hill, but better is often the enemy of good enough. Such telescopes could still do a lot of good science, and be out away from the increasing orbital clutter and light pollution of Near Earth Orbit.

As space lift gets cheaper with reusable boosters and regular launches, it could become feasible to refurbish space telescopes already up there whether they were designed for it or not.

Perhaps we are on the verge of a golden age of space astronomy. I hope so.