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Comment by system2 | Hacker News Reader

For those who might not read the whole thing, here is a summary:

The Hubble and James Webb Space Telescopes have astounded with cosmic images, but a new era of Extremely Large Telescopes (ELTs) is emerging. With mirrors up to 39m in diameter and advanced optics, ELTs promise 100 times Hubble's light-gathering power. The European Southern Observatory (ESO) aims to complete the 39m European ELT in Chile by the decade's end. The US projects, Giant Magellan Telescope and Thirty Meter Telescope, face funding challenges, prompting a call for the US National Science Foundation to lead and consolidate efforts into a single ELT project.

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So there doesn't seem to be any 'risk' as all projects are going ahead just fine. Well except Hawaii but that's not a new problem.

The space based platforms are also not at any risk, they still have capabilities the land based ones will not have such as the ability to see wavelengths absorbed by the atmosphere, weather independence and the lack of satellite interference.

Hubble is going to require a reboost and perhaps even a maintenance mission some time within the next decade, so that's a very real risk to that mission ending. I hope we can figure something out. At this point, I argue even just keeping Hubble flying is a great boon for space exploration advocacy.

Otherwise though, I agree there isn't any "risk" insofar as anything hitherto unseen. Science projects fighting for funding is nothing new and positively mundane.

Wouldn't it make sense to allow it to decay and spend the money on something more modern? Optical sensors have had great advances in the meantime, the original Hubble lenses were wrong and a correction had to be installed, and the cost to put something in low orbit went down a lot.

Also we have better understanding of the failure modes of gyro bearings so we can build them to be less failure-prone (someone more knowledgeable please correct me if I didn't get this right).

The original solar panels must have degraded quite a bit by now, so you'd eventually have to replace those too - overall it doesn't feel cost effective to keep fixing the thing.

>Wouldn't it make sense to allow it to decay and spend the money on something more modern?

Objectively speaking? Yes, money would be better spent developing and launching a newer and better Hubble 2.0.

But remember: This is the Hubble Space Telescope we're talking about here, Hubble has acted as the de facto ambassador of space for many generations of people today. The Hubble Space Telescope is a cultural icon of space exploration, it isn't just a space telescope anymore.

Consider that when the Space Shuttle program was on its final legs, NASA was convinced to fly one last reboost and maintenance mission to the Hubble because it is the one and only Hubble Space Telescope. I personally think it's worth spending money to preserve and use Hubble as long and far as we can.

Valid point but the solution is right in your own post: Just call it Hubble 2.0 and preserve its symbolic value. Spend a little telescope time to repeat a few of its most iconic shots (Ultra Deep Field for example), post them side to side, people will love it and it'll still be Hubble.

> Wouldn't it make sense to allow it to decay and spend the money on something more modern?

It wouldn't. The cost to boost Hubble and keep it around is small. About the cost of an ISS resupply, less than $150M.

The cost to build a replacement? Unbounded. JWST was supposed to be completed in ~5 years and cost $1B. It took over 20 years and $10B.

The cost of boosting Hubble won't impact any replacement we might design.

Yeah and Hubble was based on the keyhole spy satellites of the time and those cost like a billion each.

Of course JWST was a completely fresh design with many inherent difficulties.

Ground-based telescopes have capabilities that space-based telescopes do not. You can build much larger telescopes on the ground, attach much larger and heavier instruments to them, and perform regular maintenance and upgrades. Space-based and ground-based telescopes are not interchangeable, and you need both in the modern day.

The editorial is a little indirect but the funding challenge is the key bit.

What the editorial is saying is that both the currently private projects in US to build the new generation of ground telescopes need government money to be completed but it is unrealistic for government to fund both. Therefore the government should pick one to take over and then make sure it has enough money to be built.

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