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Comment by genidoi | Hacker News Reader

In unrelated news the cost of launching a space telescope (that doesn't suffer from atmospheric perturbations or cloud cover) has decreased by several orders of magnitude.

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> It is this author’s opinion that any correlation between mass and space telescope cost is a coincidence.

From "Survey of cost models for space telescopes"

https://doi.org/10.1117/1.3430603

A decade old study, using only NASA telescopes, using only super expensive launch systems.

Now the Falcon Heavy can lift over double the payload mass of the Space Shuttle to orbit, for less than 1/40th the cost per pound.

Launch costs are only a fraction of the cost. The cost of a space telescope itself is massive, regardless of launch cost. The James Webb telescope is massively over budget but even it’s original $1 billion cost and 10 year build time is much more than many ground based observatories would have costed at the time. Currently it’s cost is about x10 it’s original estimate and 14 years late, partially because it’ll be on its own once it’s launched.

On the ground, $1 billion or less buys you an extraordinarily large telescope such as a 40 metre mirror or a distributed array. These are needed to study very distant objects in detail and impossible to build in space.

True, but if James Webb launched in a fairing as big as Starship, the unfolding mechanism that’s driven most of it’s delays and cost overruns would have been far simpler.

And space telescopes don’t suffer from atmospheric distortion, can focus on the same spots for days straight to collect more light, etc. those are huge advantages.

> using only super expensive launch systems.

And _yet_, despite launch cost supposedly being suuuuper large, weight played no clear role in total cost. Not sure how that is a counter argument?

The satellite itself is way more expensive then a ground based telescope. Maintenance of a space telescope is much more expensive then a ground based telescope. All in all launching a satellite is just a fraction of the total costs of a space telescope.

On top of that SpaceX has also not proven to be real friendly towards space telescopes, so that just "moves" the problem. See for example: https://www.forbes.com/sites/jonathanocallaghan/2019/09/02/s...

Your link describes a failure of SpaceX's internal ticketing system which resulted in ESA thinking that SpaceX were ignoring them.

It seems unfair to paint SpaceX as anti-space telescope on that basis.

> Your link describes a failure of SpaceX's internal ticketing system which resulted in ESA thinking that SpaceX were ignoring them.

I'm not saying they are anti-space telescope. I'm saying I'm seeing little evidence they want to play nice with other people who have a stake in space. I have seen mostly evidence to the contrary.

Regarding that particular incident; ESA's (way larger) satellite had that orbit / trajectory for quite a while before SpaceX decided to enter it's path. SpaceX should never have created that situation to begin with. And when the situation was created (for whatever reason) SpaceX should have manoeuvred their satellite out of the way without requiring ESA intervention to begin with. And then when ESA had to ask they should have responded. That can't all be blamed on a faulty ticket system...

Satellites naturally cross paths over time, there is no “ESA” path. This is standards and expected, SpaceX is only guilty of a support failure, which has been corrected.

And SpaceX has designed and is implementing shade visors on all new Starlink satellites at their own expense, for the sole reason of reducing their reflection and brightness for astronomers.

No one made Elon do that, he chose to significantly increase the cost and complexity of his satellites to help astronomers.

As you say, there are standards and expectations that SpaceX failed to uphold. They shouldn’t be praised or thanked for doing what they should have done in the first place and only corrected after been called out.

You are confusing two seperate things.

The ESA thing, and the standards based thing, is a communication failure, where SpaceX failed to promptly reply to an email by accident.

The reflectivity based thing is something without standards more stringent than what SpaceX was already complying with, which they voluntarily chose to improve to be a good citizen, and in which they are going above and beyond the existing standards.

Not entirely unrelated. The economies of scale created by the demand for launching these "megaconstellations" is going to be a big driver for said cost reductions.

The answer shouldn't be that astronomy has to have smaller, less efficient and slower built space telescopes that cost up to 100 times as much as ground telescopes.

Size matters for telescopes and there's a limit to what can be launched. Whilst Hubble provided amazing insights it can't replace all ground telescopes. Additionally ground based telescopes can be fixed and upgraded without the need for an astronaut to be flow to repair it, a capability that doesn't currently exist.

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