231–240 of 395 posts
Seems like the perfect use case for Vantablack. Of course the satellites will still block ER as they pass across the sky, but at least if they aren't reflecting so much light it would surely be of some help?
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It's the other way around. It's possible to escape light pollution by moving away from electrified areas, whereas satellite streak ruins observations in every part of the world. Besides, the streaks are not really localized in the image. Its glow reportedly extends up to 15 arc seconds. That's a very large area for a carefully exposed array.
I meant light pollution affects the entire image, while a streak affects only part of it, which you can just remove. A 30 arcsec stripe on an (apparently average) 20 arcmin detector is 2.5% of the total area, so it's not a very large area. Overall, 20000 satellites at any given time cover 20k π 15acsec² of sky area, which is 0.0005% of total sky area, and over 1 second (assuming a satellite speed of 3.6 arcmin per se…
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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 / trajecto…
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.
The article covers the mitigations already in place and how they only partially resolve the issue. These satellites are low, bright (at dawn/dusk) and very soon to be incredibly numerous. Yes, it is possible for data workflows to post-process these streaks away, but not all configurations allow this, and whereas previous intrusions were somewhat rare and could be ignored that simply won't be the case due to three com…
I personally believe that pervasive high speed internet even in remote locations will do more for humanity than the scientific cost of these satellites. However, this conversation has basically been skipped over. Maybe you're right and I'm wrong. The constellations are being launched, and there's zero chance of shutting them down once they're serving a commercial role. Considering the abundant red tape in the modern…
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.
> 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
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.
This is bad. This is really really bad. The EU has invested billions in telescopes and that's now going to go to waste. Instead advancing human knowledge it's just going to fill rich guy pockets even more.
No, it’s not. Starlink satellites are only visible at dusk and dawn, they are in the earths shadow during prime viewing hours. And SoaceX has already added visors to make new Starlink satellites nearly invisible.
In what wavelengths?
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As I noted on a similar thread the issue is not removing the streaks, it's what data is lost behind those. If you take a look at this image you'll see that it can be a non-trivial amount of interference in some cases and that data can't just be filled in with "black". https://i.imgur.com/Qdt0N2g.png The interference also causes a "glow" effect on the CCD which corrupts the data well beyond the edges of the main strea…
I love all of the comments about using software to filter out the images. This response is so obvious that it is from someone who has never worked with data from imaging the sky, and probably have never thought about it more than a drive-by comment. "Just filter it out" they say. And replace it with what? An average of near by pixels? An AI background replacement? That's just bollocks. Every single dot in the sky is…
As a reminder, astronomy is not as much about the 'image' as it is about the 'measurement'. Editing pictures like in Insta is not the point here, you can't fill things in.
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This is a logic flaw I see everywhere. Making a proposition for what might have been there is not a useful scientific instrument. And especially not when unseen anomalies are an integral part of pushing your field forward. If you're inferring what might have been there you're explicitly filling in based only on what you already know.
I agree, but isn't filing in what you already know a common technique when presenting things for human consumption? I'm thinking scanning microscopy, SEM, STM, etc. The image implies that all the data is from the same instant, when it's not. Normally that's OK, but it's not always.
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I meant light pollution affects the entire image, while a streak affects only part of it, which you can just remove. A 30 arcsec stripe on an (apparently average) 20 arcmin detector is 2.5% of the total area, so it's not a very large area. Overall, 20000 satellites at any given time cover 20k π 15acsec² of sky area, which is 0.0005% of total sky area, and over 1 second (assuming a satellite speed of 3.6 arcmin per se…
The problem is with the exposure. 1min exposures are common in astrophotography, but astronomers are complaining about the types that need night-long exposure - ones that try to study cosmology, stellar composition etc. Many observations (like SDSS) are also large field observations that observe many objects simultaneously. Even a single streak can ruin an entire exposure. The odds just grow considerably.