American scientists boldly imagine! They are going to build the latest radio telescope, with an area of staggering 100 square kilometers, far larger than our China Sky Eye . Not only that, this telescope is not even built on Earth, but on the moon!
This sounds a bit incredible, but scientists have indeed wanted to build telescopes on the moon long ago.
We know that only one side of the moon can face the earth, which is the front of the moon; the other side can never see the earth, also called the back of the moon. Scientists believe that the back of the moon is one of the best radio telescope sites known to humans.
Why is China's Sky Eye built in the mountains and valleys of Guizhou? It is to avoid interference caused by human electronic devices. This interference may seem weak, but it will cause huge interference to radio astronomical observations, so visitors cannot even carry their mobile phones. In contrast, the moon has a diameter of 3476 kilometers, and its huge body can completely block electromagnetic interference from the earth .
Since the surface is not good, can we build this kind of telescope in space? The answer is also no. In space, plasma noise from solar wind will interfere with radio astronomy observations. By contrast, the moon can provide a plasma cavity that shields this interference. It can be said that the back of the moon is the closest and most perfect electromagnetic wave quiet area.
Scientists had this idea decades ago. Recently, American astronomers and engineers pointed out that the future has arrived, and mankind has the ability to achieve this feat and can start preparing.
They named this project " for radio scientific surveys of the Dark Ages and exoplanet ", which is simply called FARSIDE, which happens to be the back of the (moon), and we will call it Month Back Plan for short. According to the previous FARSIDE concept we introduced in 2020, the moonback telescope has a caliber of about 1 km.
Caltech Astronomy professor Gregg Hallinan is one of the researchers of this concept. The idea he proposed is even more grand, covering an area of more than 100 square kilometers!
Hallinan describes it to us that the telescope can take unprecedented radio images of other stars in the universe, help us understand their coronal matter ejection and high-energy particle events, and can also help us understand the magnetosphere around exoplanets in their habitable zone, which is crucial for the habitability of a planet.
It can also be used to study the activities of our own stars - the sun, and can also observe other objects in the solar system. It is even expected to answer the puzzle of whether 's ninth largest planet, , exists. It can even observe the dark age of the universe, that is, the early history of the universe. At that time, there were almost no stars and galaxies in the universe. This history has always been the most curious topic for astronomers.
To meet this research, the telescope designed by the researchers can be observed at extremely low radio frequency, with a frequency of 3MHz. Using the array of bipolar dipole antennas they designed, the sensitivity of the moon back telescope can be 100 times higher than that of the ground, achieving unprecedented super observation capabilities!
has said so much, how should Americans build it? You know, they can't even send astronauts to the moon now, let alone build telescopes!
However, building a telescope does not necessarily require humans to go to the moon in person, and NASA's robot is expected to complete this task.
In fact, over the years, NASA Jet Propulsion Laboratory (JPL) has been developing the Axel series of rovers. Its appearance looks very much like the balance bike , but it is larger and can be combined into a four-wheeler. Axel is good at unmanned work on the surface of the ball and is able to work on steep, rough terrain. After more than 20 years of development, its functions have become very powerful and have been waiting for tasks that suit you.
In addition to cooperating with JPL, they also took a fancy to the Blue Moon Lander of Blue Origin .Blue Origin is a very powerful private space company, and its head is the former richest man in the world, Jeff Bezos . Steve Squyres, the company's chief scientist, is also the main researcher of the two major Mars rovers of NASA's Courage and Opportunity , with rich experience. After the completion of
, the energy required for telescope operation is also a problem. The researchers noted that they could use multitasking radioisotope thermal generators (MMRTGs) to provide power. Moreover, if they can use the Blue Moon lander, they can also improve the design in this area.
Even if people are not needed, how should the materials used to build telescopes be transported? In fact, this telescope is not exactly the same as our Chinese Sky Eye. Although they are both called radio telescopes, the United States is preparing to build a radio telescope array in the back of the moon. This type of telescope does not need to use reflective units like the celestial eye, nor does it need to use lenses like optical telescopes. Even the antennas of the telescope array on the surface of the earth are not used, but use special tethers.
According to Hallinan's idea, this tether is flat and has a thickness of only 1 to 2 mm. It has embedded antennas and has the ability to optical communication and conduct electricity. It only needs to be laid on the back of the moon according to the designed pattern.
Specifically, building the telescope requires the use of the Axel rover to pull a tether up to 12 kilometers, with 64 remotely powered electronic nodes on each tether.
Researchers designed four different array distribution modes, among which the shape of the four-arm spiral is the best choice, that is, using four rovers. Because this can minimize the trajectory of each rover, in other words, the length of the tether can be short enough to have a relatively low load-bearing capacity requirement for the rover, which is easier to achieve.
According to Hallinan and others' concept, the telescope of the Moonback Project will cover an area of more than 100 square kilometers!
Another problem is that it is the harsh environment on the surface of the moon. You should know that the moon's temperature can drop below -100℃ in the dark, which is a huge threat to many devices. However, JPL engineers have designed a new antenna receiver whose electronic components can work properly in extremely low temperatures, which does not require additional heating facilities.
Despite these solutions, the researchers are not the ones who made the final decision. Hallinan pointed out that if the next step can be carried out immediately, the telescope-related facilities can be launched to the back of the moon as early as 2028.
As for when NASA will take such action, it is hard to say.
