A weenie telescope past Saturn may be better than a beefy one near Earth
Dozens of space-based telescopes operate near Earth and provide stunning images of the universe. But imagine a telescope far away in the outer solar system, 10 or even 100 hours farther from the Sun than the Earth. The ability to look back at our solar system or their contemporaries into the darkness of the distant cosmos would make this a very powerful scientific tool.
I am an astrophysicist expert who studies the formation of structures in the universe. Since the 1960s, scientists like me have been debating the important scientific questions that we could answer with a telescope embedded in the outer solar system.
So what would such a mission be like? And what science could be done?
A tiny telescope far from home
The scientific strength of a telescope far from the Earth would come from its location, not its size. Plans for a telescope in the outer solar system would be placed somewhere beyond the orbit of Saturn, about a billion or more miles from Earth.
All we would need to do would be install a very small telescope - with a lens around the size of a small plate - to achieve some very special celestial views. Such a telescope could be built to weigh less than 20 pounds (9 kilograms) and could be turned back on almost any mission to Saturn or beyond.
Although small and simple compared to telescopes like Hubble or James Webb, such an instrument operating away from bright sunlight could make measurements that are difficult or completely impossible from a viewing point. near Earth.
Outside looking in
Unfortunately for astronauts, getting a selfie of the solar system is a challenge. But seeing the solar system from an outdoor observation point would reveal a lot of information, especially about the shape, rotation and combination of the dust cloud surrounding the sun.
Imagine a street lamp on a foggy evening - standing far away from the lamp, the moving music can be seen in a way that no one standing under the street light could see.
For years astrophysicists have been able to take images and study the dusty discs in solar systems around other stars in the Milky Way. But those stars are a long way off, and there are limits to what astronauts can learn about them. Using observations looking back at the sun, astronomers were able to compare the shape, properties and combination of distant dust clouds with detailed data on the Earth 's own solar system. This data would fill gaps in knowledge about solar dust clouds and make it possible to understand the history of dust production, migration and destruction in other solar systems in which there is no hope of personal travel.
The deep darkness of space
Another advantage of placing a telescope far from the Sun is the lack of reflected light. The disk of dust in the planetary plane reflects sunlight back at Earth. This creates smoke that is between 100 and 1,000 times brighter than light from other galaxies and clears views of the cosmos from near Earth. Placing a telescope outside this cloud of dust would place it in a much darker place making it easier to measure the light coming from outside the solar system.
Once there, the telescope could measure the brightness of the earth's ambient light over a wide range of waves. This may give us an insight into how the first stars and galleries approached. It would also enable researchers to determine models of the universe by comparing the expected amount of light from each galaxy with precise measurements. Deficiencies could point to problems with models of structure formation in the universe or perhaps to new alien physics.
Into the unknown
Finally, increasing the distance of a telescope from the Sun will allow astronomers to perform a special science that takes advantage of an effect called a gravitational lens, in which a large object eliminates the light of its path while moving beyond something.
One use of gravitational lensing is to detect and quantify false planets - planets that move over interspecific space after being ejected from their home solar systems. Since false planets do not emit light on their own, astronomers can look for their effects on the light from celestial stars. To differentiate between the speed of the lens object and its mass requires views from a second location far from Earth.
In 2011, scientists used a camera on the EPOXI mission to the asteroid belt to find an object the size of Neptune and its weight floating free among stars in the Milky Way galaxy. Only a few false planets have been discovered, but astronomers suspect that they are very common and could trap the formation of solar systems and the frequency of planets around stars.
But perhaps the most interesting use for a telescope in the outdoor solar system is the ability to use the sun 's own gravitational field as a large lens. This type of measurement can allow astrophysicists to map planets into other star systems. Maybe one day we will be able to name continents on an Earth-like planet around a distant star.
Since Pioneer 10 became the first human object to orbit Jupiter in 1973, only a handful of astrophysical studies have been conducted from outside the Earth's orbit. Missions to the outer solar system are rare, but many teams of scientists are conducting studies to show how an extrasolar telescope project would work and what could be learned from one.
Every 10 years or so, leaders in the fields of astronomy and astronomy gather to set goals for the next ten years. That plan for the 2020s is expected to be released on November 4, 2021. There, I expect to see discussions about the next telescope that could change astronomy. Bringing a telescope to the outer solar system, while ambitious, is well within the technological capability of NASA or other space agencies. I hope one day soon that a tiny telescope on a lonely mission in dark areas of the solar system will give us amazing views of the universe.
Article by Michael Zemcov, Associate Professor of Physics, Rochester Institute of Technology
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