Christmas Eve 1968 – Apollo 8 astronaut Bill Anders takes a picture that will soon rethink humanity’s view of the universe. It was image of the earthbut from the point of view of the moon.

When you look at this picture, a fresh planet looks at you, levitating just above the lunar horizon like a turquoise sunrise. And it was this resemblance that earned Anders’ photo the perfect name: Earthrise.

Sunrise on Earth during the first crew trip around the moon, Apollo 8.

Bill Anders / NASA

From the time Anders made his shot from a spaceship in lunar orbit, scientists have obtained absolutely mind-boggling images of Saturn’s rocky rings, The azure shades of Neptune and even The orange marble stripes of Jupiter – but these pictures hardly scratch the surface of the planetary society of our universe.

There are thousands of extraterrestrial worlds floating beyond our solar system, but they remain hidden from the human eye because they are light years light years away. Our telescopes are too far away to capture their beauty. They appear only as blurred light points – if they appear at all.

Soon, however, these fuzzy exoplanets may come into focus. In Tuesday in The Astrophysical Journala team of Stanford researchers has outlined a futuristic telescope concept that could theoretically take pictures of alien orbs with enough clarity to rival even Anders’ iconic sunrise.

It’s called the “gravity telescope.”


The planets are not on the scale of this image. It shows portraits of Hubble from 2021 on outer planets, with Jupiter, Saturn, Uranus and Neptune moving from left to right.

NASA, ESA, A. Simon (Goddard Space Flight Center) and M. H. Wong (University of California, Berkeley) and the OPAL team

“With this technology, we hope to take a picture of a planet 100 light-years away that has the same impact as the picture of Apollo 8,” said study co-author Bruce Mackintosh. said in a statement. Mackintosh is a professor of physics at Stanford University and deputy director of the Kavli Institute of Astrophysics and Particle Cosmology.

The telescope will work, researchers say, using a mind-boggling phenomenon called gravitational lenses.

Gravitational lenses? What is this?

In short, gravitational lenses refer to the fact that light emanating from the stars or other cosmic objects distort and distort as they pass a supermassive, gravitational dense cosmic body.

The reason for this is due to the general theory of relativity, a well-established theory of gravity, first proposed by Albert Einstein in the early 1900s. We will not go too deep into the general theory of relativity, because it will require a lot of physics that burns the brain, which I will keep for another time.

For gravitational lenses, you just need to know that the general theory of relativity assumes that space and time are interconnected like a giant piece of molded fabric. This fabric can bend and twist like your clothing and generally does so when there is an object in it.

Galactic clusters distort it like no other, black holes distort it a lot, the Earth distorts it somewhat, the moon distorts it a little, and even you distort it a little. Everything distorts it, but the bigger the object, the more distortion you get.


In this photo, the gravitational lens distorts the light coming from galaxies. This is why they look like spots or streaks.

NASA / ESA / K. Sharon / E. Ofek

And the important thing about gravitational lenses, when light passes through one of these bases, something like a magnifying glass effect is created. Astronomers usually use this effect around the most distorted areas – usually galactic clusters – to “magnify” distant objects. Gravity lenses give them a much better picture of what they are looking at.

The concept of the gravity telescope works with the same idea, but with a few tweaks.

Characteristics of the gravity telescope

The first difference is that researchers are proposing to use our own sun as a source of deformation for the gravity telescope, instead of the usual galactic cluster. And second, the gravity telescope requires an extra step, which is something like a Sherlock Holmes-style deduction.

According to the document, the device will first capture the light of the sun-distorted exoplanet (standard gravitational lenses), but then the telescope’s so-called solar gravitational lens will use this light data to work backwards and reconstruct what the exoplanet actually looks like in the first place.


To demonstrate how this will work, the researchers used existing images of the Earth taken by the Dscovr satellite. This spaceship is located between our planet and the sun, so it is quite ideal for a theoretical test of the gravity telescope.

The team released images of our planet using a computer model to see what the Earth will look like through the gravitational effects of solar lenses. They then developed and used an algorithm to “unfold” the light or to unfold the light and start the reconstruction process.

In short, work.

An example of the reconstruction of the Earth using the light ring around the sun, designed by the solar gravitational lens. The algorithm that allows this reconstruction can be applied to exoplanets for superb imaging.

Alexander Madurovich

“Folding light bent by the sun can create an image far beyond that of an ordinary telescope,” said Alexander Madurovich, a doctoral student at Kavli’s Institute of Particle Astrophysics and Cosmology and co-author of the study. statement. “This will allow us to study the detailed dynamics of the planet’s atmospheres, as well as the distribution of clouds and surface characteristics that we have no way of studying now.”

He added that “scientific potential is untapped mystery because it opens up this new ability to observe, which does not yet exist.”

Without using the team’s gravitational lens, we’ll need a telescope that’s about 20 times wider than Earth to take a super-clear picture of an exoplanet – but the gravitational lens, the team says, will handle a Hubble-sized telescope.

There is a huge warning

For any of this to work, the gravity telescope must be at least 14 times farther from the sun than Pluto. Yes.

And this, the study authors write, “will require extreme patience with conventional and existing missile technology”, with a travel time of about 100 years “or progress in propulsion to achieve higher take-off speeds, such as solar sail”.

In other words, it will take about a century to get the gravity telescope to where it needs to be. solar sails, like thisit can potentially reduce travel time to something like 20 or 40 years, but sunscreens are a long way from regular use.

However, researchers say they are driven by the greater consequences of taking spectacular photos of exoplanets one day. For example, it could be very helpful to look for evidence of extraterrestrial life.

What the brilliantly colored exoplanets of the universe's research team might look like.

The artist’s conceptual image of 25 exoplanets lurking beyond our solar system. With the gravity telescope we may be able to take real pictures of them.

ESA / Hubble, N. Bartman

“This is one of the last steps in finding out if there is life on other planets,” Mackintosh said. “By taking a picture of another planet, you can look at it and probably see green spots that are forests and blue spots that are oceans – so it would be hard to argue that there is no life on it.

And as for my fellow amateurs, planetary fans, I think looking at a picture of an exoplanet would correct our existential perspective – the way Earthrise once did for humanity.

Even now, watching Earthrise undoubtedly evokes a strange feeling in us; a sense of disbelief that we are traveling through space on what is actually a giant round ship.

How will we feel when we see all the other giant round ships in the universe?

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