Observed a couple of days ago in the night skyIn some countries, the “train” of SpaceX’s first 60 Starlink satellites not only aroused interest among ordinary people who wondered what they saw, but also laid a grain of concern among some astronomers who asserted that the Ilon Mask satellite network would turn into a real problem for ground-based optical and radio astronomy observations. A few days have passed, but on the Web, passions do not subside. On the contrary, a real war began between supporters of the Starlink global satellite network and its opponents.
Astronomers vs. Starlink Satellites
“I understand that people are impressed with all theseimages of the “train” of Starlink satellites from SpaceX, but personally it makes me seriously think about possible problems. They are very bright and soon there will be a lot of them, ”planetologist Alex Parker tweeted.
“These satellites just flew right over my head. Very bright, some, almost like the North Star. Awful thing. And yes, I did not see the stars on their background, ”he added later.
Parker also noted that 12,000 bright satellites,in low Earth orbit, can exceed the number of stars visible in the night sky with the naked eye. However, he did not make final conclusions on this score, noting that everything will become clear only when the satellites occupy their planned orbits.
And this is just one of many similar messages on the social network, in which scientists express concern about future problems. More details about them can be found in our previous article.
The head of SpaceX listened to this whole thing and finallydecided to speak, at the same time answering some questions of excited enthusiasts of space exploration. So one of the Twitter users asked Mask to comment on the situation around the conversations that SpaceX satellites are too bright and carry the potential threat for the emergence of even more space debris in the orbit of our planet.
"There are already 4900 satellites in orbitpeople never notice. Starlink satellites are also impossible to see if you do not look at the sky very much. They will not create any problems for astronomy. In any case, we need to bring more telescopes into space. Atmosphere interferes with observations, ”answered Musk.
Radio astronomer and planetologist Dr. Mary Knapp,working with telescopes LOFAR (LOw Frequency ARray - “low-frequency antenna array”) and VLA, Mask was not at all convinced by this answer. She noted that such open arrogance and self-righteousness of the head of SpaceX "deprives her of speechlessness".
“To write off all terrestrial astronomy simply because it interferes with its business. Brilliant! (replaced by mat, - ed. edition), ”the scientist commented.
Why do we need terrestrial astronomy?
Knapp reported that she herself takes part increation, and also uses space telescopes in her research, and she would never even have thought of somehow diminishing the importance of ground-based astronomical observations. In addition, she explained that the cost of creating and launching space telescopes with an appropriate aperture can be ten times more expensive than building and using ground-based ones. In her opinion, the possibility of effective scientific research only with the participation of space telescopes will lead to the fact that it de-democratizes and makes astronomy as science inaccessible to most people, leaving the possibility of conducting astronomical observations only for the richest scientific institutions and space agencies.
SpaceX rockets do not make astronomy cheaper
One user asked Knapp,Can SpaceX rockets significantly reduce the cost of launching new space telescopes? She replied that in her opinion, this is unlikely, since most of the costs are devoted to the design and development of durable devices that do not imply the possibility of maintenance.
These were the pictures of Starlink satellites by Victoria Girgis, an employee of the Lowell Observatory (USA), while observing a group of galaxies.
And here is another example of “photobombing” by one of the Starlink satellites, flying against the background of the star Vega. Photo taken by British astrophotographer Steve Brown.
Some questions addressed directlyMask himself, also found the answer. So, one of the readers wondered whether it was possible to reduce the reflectivity of the satellites (albedo) Starlink, to which Musk replied that he had already instructed the development team of the devices to solve this issue.
"I agree, last week sent a requestStarlink team with a specific task - to think of a way to reduce their albedo. We will get more detailed data on the current situation when the devices reach the specified orbits and direct their solar panels towards the Sun, ”Musk wrote back.
Science and capitalism
As it turned out, not everyone supportsscientists concern about the likely difficulties that can be created by the global satellite network SpaceX Starlink. One user noted that if satellites can help billions of people living in remote places from large cities with access to inexpensive and fast Internet, then such sacrifices will be a fair price.
"Precisely, the potential help of billions of peoplebeing in unfavorable economic conditions is a great blessing, ”Musk agreed, adding,“ Nevertheless, we will make sure that Starlink does not have a significant impact on astronomical research. We care a lot about science. ”
As one of the measures that will solveThe problem of excessive reflectivity of Starlink devices Musk called the possibility of their redeployment. Each of the devices weighing 227 kilograms is equipped with ionic engines operating on krypton gas. Due to them, the satellites, if necessary, can be shifted from orbit (the height of the planned orbit will be 550 kilometers).
"If you need to change the orientation of the satellite to minimize the effect of the reflection of sunlight, which will interfere with astronomical observations, then we will do it without any problems," wrote Musk.
He also added that for radio astronomyResearch satellites also will not be a problem, because the company abandoned the use of certain frequencies in the Ku-band (devices will work there) that are used in radio astronomy.
One of the authors of the portal Universe Today FraserCrane suggested Mask as a compromise to consider the possibility of using Starlink satellites as a carrier base for compact space telescopes, to which the head of SpaceX answered that he would be happy to consider such an idea.
Start a new space race
It should be recalled that not only SpaceX leadsdevelopment of mega starships of near-earth Internet satellites. Yes, it will potentially become the largest (12,000 devices!), But not the only one. For example, the British company OneWeb has already launched the first six satellites out of a planned 648 this year. Canadian satellite operator Telesat is going to build a network of 292 new devices. Amazon also decided to connect to satellite coverage. About the possibilities that these operators will offer, as well as in general, the need for satellite Internet can be found in our previous material.
In any case, in the coming years, spacetraffic in Earth orbit will increase markedly. Because of this, some people may have a question about whether such a large number of satellites will interfere with future space launches?
Can satellites prevent space launches?
By adding the above numbers, we get 16,176 devices. Adding here another 4900 satellites already working in orbit, we get a figure of 21,076 vehicles. Is it a lot or a little?
Imagine not living on Earth 7.7 billion.people like now, but only 21 thousand people. With such a population density, one could search for someone on the planet all his life and as a result not meet a single person. Now let's go up to Earth orbit, where the area of the sphere is even larger. Much bigger. So the density there is still much less.
Twenty one thousand devices - it is insignificantlittle compared with the area of the Earth's orbit (510 million square kilometers). The probability of crashing into one of these satellites will be about the same as the probability of being hit by a stone thrown from space if there were not 21.7 billion people on the planet. On the other hand, several cases of collisions of spacecraft convince us that such incidents do happen. But they are rather an exception to the rule.
Something like this now looks near-earth orbitwith all satellites, large natural celestial objects, as well as large space debris objects. You can view the online version at this link. And they somehow manage to launch rockets and send missions to deep space.
In any case, I would like to know which side our readers will take in the question of the benefits and harms of the Starlink satellite network. You can share your opinion in our Telegram chat.