100s of astronomers warn SpaceX Starlink satellites could block future science | Hacker News Reader

100s of astronomers warn SpaceX Starlink satellites could block future science

independent.co.uk

26 pointskevmo10 comments

They should think on cosmological time scales, cheap access to space means cheap access to space telescopes (which in principal can gather less noisy data)

Our telescopes (Imaging Air Cherenkov Telescopes) can only work on Earth as we use the atmosphere as detector medium.

Space based telescopes can simply not be build large enough no matter how cheap some tons to LEO will get.

Does Earth have the optimal atmosphere for this technique? How about putting telescopes on other planets with atmosphere?

> Imaging Air Cherenkov Telescopes can only work on Earth as we use the atmosphere as detector medium.

Considering their operating principle, are they actually affected by satellites?

Yes, every foreign light source is disturbing.

We measure down to single photons in nanosecond timescales and a mag 3 or brighter satellite moving through the field of view is definitely not a good thing.

Not to detract from the topic, but this has been covered on HN many times in the past year or so.

Also, my understanding (from past HN discussions!) is that SpaceX are working on making their satellites less problematic for astronomers in the long term, although obvs we’ll have to see how well that the turns out.

Can someone explain to me how it's a problem?

It's all just data today, isn't it? You can erase the from long time exposures than. Or does the brightness cause lens flares and stuff?

If it was about hobby astrophotography I'd see it right away :)

You cannot "delete" something from a long exposure, how would you think that worked?

You "delete" it by composting multiple images with a mask applied to the object position. This is done relatively frequently.

The human visual system uses this technique to some extent as your optic nerve creates a relatively large blind spot in each eye. Even with one eye closed, your visual system "deletes" this blind spot via image composting from visual memory or rapid eye movements.

The human eye deletes even more and you can trick it in to showing! you can see a network of blood vessels:

https://youtu.be/L_W-IXqoxHA?t=372

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