Goregue t1_jaimbad wrote

"Starlink is saving lives in Ukraine, providing high speed internet to native reservations in Canada, hooking up schools in Africa to the internet and provides a viable method for my local sugar shack to get faster than dialup speeds."

Except for the first one, all of this can be done with fiber networks. Satellite internet should only be used for emergencies and extremely remote locations, it should be the exception rather than the norm.

"Your dislike of SpaceX seems to be motivated by Reddit Cool."

I dislike only Starlink, and that's because it is interfering with astronomical observations. I applaud SpaceX's efforts with reusable rockets, Starship, the dragon capsule.

"Starship has a 9 m diameter and can carry a 7 m mirror without the origami required for JW. The astronomy world is already looking at it."

Starship is still unproven. When (or if) it is operational, it will certainly be very useful to launch cheaper space telescopes, but this does not mean in any way that space telescopes will make ground-based observatories obsolete. Ground telescopes will always be cheaper and more convenient to operate and maintain.

And a 7m space mirror is not enough when ground telescopes are already at 30-40 meters. So "space origami" will still be necessary if we want to rival the resolution of ground-based telescopes.

"In the last 120 years we moved from gliders to Artemis. It will not take centuries to take the next steps."

And in the last 50 years we moved from crewed missions to the Moon to just now returning to crewed missions to the Moon. For the last 50 years a Mars crewed mission has always been just "20 years away". Progress is very slow with the level of funding we are seeing.


Goregue t1_jaifcml wrote

If ground-based telescope are made unusable, astronomy will stagnate and will pretty much stop to exist. No one will be able to pursue a carer in astronomy when no research projects are possible. Even if space telescopes still exist and a fraction of ground-based telescopes are still usable, astronomy will not be sustainable. Astronomers are not doing science just for fun, they need money to survive and if astronomy cant provide this, they will be forced to move to another field.


Goregue t1_jaiepao wrote

"People like you...huh. That is a very loaded phrase. What kind of people are "like" me."

People that superficially like science, but in reality have no idea how it actually works behind the scenes. They only like to see the latest pictures and results from Hubble or JWST. They are a fan of Elon Musk and SpaceX just because they think it's cool. I am not saying you are like this, but this is the impression I get from these people that are blindly in favor of satellites constellations.

"Space telescopes are currently orders of magnitude more expensive. Where will they be in 30 years?"

Yes. Space materials are necessarily more expensive than material you can use on the ground. They need to survive much harsher conditions, under no maintenance, with limited possibilities to troubleshoot problems, and have stringent constraints on size and weight. Space telescopes will always be much more expensive than ground based telescopes.

"Nobody suggested to move all of astronomy to space (strawman alert). But if the article is right maybe a huge chunk has to."

"People" say all the time that we need to move astronomy to space. It doesn't matter if they mean 100% of telescopes, or 90%. The effect is the same, they are proposing a solution that is completely non viable.

"We are centuries away from any given technology? And you get these dates how?"

It took NASA 20 years to develop JWST. At a cost of 10 billion dollars. And this is a 6-meter diameter telescope. The next generation flagship space observatory is planned to be a 6 to 10-meter telescope that will launch in the mid 2040s at a cost similar to JWST. To rival the resolution capabilities of ground-based telescopes, we would need to build a 30-meter space telescope. Thinking that we are on the brink of achieving this is completely illusory.


Goregue t1_jaibtby wrote

Why are you so keen to downplay the effects of these satellites constellations? Astronomers are trying so hard to warm the public but people simply choose to ignore them and choose to believe that it's not really a problem and that we will easily mitigate the satellites. It reminds me of the climate change debate, where scientists tried for decades to warm the public of this danger, but people simply ignored them, and now that it is becoming mainstream to accept climate change it is too late. Of course satellites constellations are not at the same level of threat as climate change, but the same logic applies. In fact, I suspect there is a great care of astronomy institutions and the writers of these articles you linked to seem "moderate" on this issue, otherwise people would immediately think they are crazy and would promptly ignore the issue. Exactly like what happens with climate change. So stop choosing to believe that everything is okay when it isn't. Satellites constellations are a huge deal and anyone that cares about science should be alarmed by them.


Goregue t1_jai81dk wrote

You are cherry picking data to seem like there is no problem. From the same article 1 you link, it says:

"The study also finds that the greatest impact could be on wide-field surveys, in particular those done with large telescopes. For example, up to 30% to 50% of exposures with the US National Science Foundation's Vera C. Rubin Observatory (not an ESO facility) would be "severely affected”, depending on the time of year, the time of night, and the simplifying assumptions of the study. Mitigation techniques that could be applied on ESO telescopes would not work for this observatory although other strategies are being actively explored."

"The ESO study uses simplifications and assumptions to obtain conservative estimates of the effects, which may be smaller in reality than calculated in the paper."

"Many of the parameters characterising satellite constellations, including the total number of satellites, are changing on a frequent basis. The study assumes 26,000 constellation satellites in total will be orbiting the Earth, but this number could be higher. "

From article 2 you link:

"In the future, the scientists expect that nearly all of the ZTF images taken during twilight will contain at least one streak, especially after the Starlink constellation reaches 10,000 satellites, a goal SpaceX hopes to reach by 2027.

"We don't expect Starlink satellites to affect non-twilight images, but if the satellite constellation of other companies goes into higher orbits, this could cause problems for non-twilight observations," Mróz says. "

"The study authors also note their study is specific to ZTF. Like ZTF, the upcoming Vera C. Rubin Observatory, under construction in Chile, will also survey the sky nightly, but due to its more sensitive imager, astronomers predict that it may be more negatively affected by satellite streaks than ZTF."

Articles 3 and 4 describe mitigation strategies that SpaceX is looking into. But crucially, it ignores that in the future dozens of companies, from all over the world, will want to launch satellites constellations. It's useless if SpaceX follows all mitigation procedures to avoid contaminating astronomical observations, but a random company from China decides that this is not important and launches the satellites anyway. The number of satellites is growing at an exponential rate, and in 10-20 years we will have possibly ten or a hundred times more satellites than SpaceX is currently planing.


Goregue t1_jai60cp wrote

It's more like 10 years if the current trend continues. Satellites constellations are growing at an exponential rate. It is an existential threat to astronomy because almost all astronomy observations are made from the ground and they will all be affected by the satellites trails. We will have less effective telescope time available, we will need more exposure times to compensate from the satellites trails (when it is possible to compensate them), which will lead to less astronomical research being done, less career astronomers, basically the stagnation of astronomy.


Goregue t1_jai46k3 wrote

Satellite constellations are a huge issue and can completely kill ground-based astronomy if the number of constellations continues its exponential grow.

"Astronomers (serious ones) have the means to easily deal with this"

So far astronomers have the means to deal with it, but what about in 10-20 years from now when the number of satellites is 100 times greater? You will not be able to take a single long exposure without these satellites appearing. It will make astronomy observation from the ground completely unpractical.

"We arent going to stop LEO traffic forever, not for any reason. Humanity belongs in space."

There is a big difference between typical LEO satellites and these mega constellations. The later are increasing the number of LEO objects at a rate unlike anything seen previously. The problem is specifically satellite constellations, NOT general LEO traffic.

"Starlink pays for Starship which will make space telescopes affordable, and ground astronomy obsolete for science purpose"

Even if the launch cost were zero, it would still be orders of magnitude more expensive to build and operate space telescopes. Astronomy with only space telescopes would only be possible if we had military-level funding for science. And there are still types of telescope which we cannot replicate in space, such as the 30-40 meter ELTs currently under construction. While building giant telescopes on the moon seems like a nice solution, it is still at least 50-100 years away and will always have an extreme cost associated with it.

"Millions of people having internet access is more important than what is realistically a minor short-term inconvenience to astronomers. Really, shame on you."

There are other ways to bring internet to everyone. And satellites constellations are not a "minor inconvenience", they have the potential to completely kill astronomical observation from the ground. It's not an exaggeration when astronomers say this. Astronomers know the observations they deal with. You should listen to what the experts say instead of choosing to believe what you find more comforting. Anyone that cares about the progress of science should be alarmed by the current trends of these mega constellations.


Goregue t1_jai1qnk wrote

People like you have no idea how much observations are done on the ground. The vast majority of astronomy research depends on ground telescopes. Even the big papers that use data from Hubble or JWST often depend on ground-based auxiliary data. It's completely nonviable to change all of astronomy to space. Even if the launch cost were zero, space telescopes are still orders of magnitude more expensive than ground-based ones. And we are still decades or centuries away from being able to build a 30-meter space telescope that would rival the resolution of the ELTs currently under construction.