Distant objects show that the solar system extends further than we ever imagined

A new method of scanning telescopic images for faint signs of rocks far beyond Pluto has revealed evidence that the disk of matter in our solar system extends much further into interstellar space than we thought.

Decades of surveillance From the shadows astronomers were left with the distinct impression of the diffuse field of icy rocks known as the Kuiper Belt suddenly It gets thinner by about 48 times the distance between the Earth and the Sun (or 48 astronomical units).

Belts of debris were seen stretching across it At least twice this distance around similar stars, making our solar system very small by comparison. With this new discovery, we may not be so unusual after all.

A team of astronomers led by Canada’s Herzberg Research Center for Astrophysics and Astrophysics hopes to discover new targets for the New Horizons probe to investigate as it travels to the far reaches of the solar system.

After he gave us some Close-ups of PlutoThe mission took pictures of A A snowman-shaped rock nearby 40 astronomical units from the sun, before continuing on its way at a speed of just under 60,000 kilometers per hour.

Finding objects that the brave little probe can observe now that it is roughly 60 astronomical units from the Sun is no easy task. To discover anything moving during perpetual midnight, astronomers have to be clever.

A commonly used technique is called Shift stacking. With so little light at the edge of the solar system, there will be few objects visible in any telescope image.

By taking photos at different times and then stacking the images on top of each other, it is possible to combine all the light from a poorly lit object into one place, increasing its clarity.

This is all good if the target’s path is known. Finding undiscovered objects this way requires a lot of trial and error, adjusting sets of images along possible orbits until a shiny gem is revealed.

Even with a computer algorithm to help, searching for hidden rocks in a pile of hundreds of images requires good old-fashioned human power, and lots of it.

To take at least some of the drudgery out of the process and speed things up, the research team took advantage of this Machine learning,Training the neural network on synthetic objects included in ,telescope images before firing it on the collected data using Subaru telescope. On Mauna Kea, Hawaii, in 2020 and 2021.

Compared to human searching through 2020 data, the machine learning technology identified twice as many objects in the Kuiper Belt, indicating a clear increase in material density at a distance of about 60 to 80 astronomical units along New Horizons’ Earth path.

The results could help explain the anomalous glow detected Whether by investigation Like fur Hubble Space Telescopewhere additional debris contributes its own reflective layer of dust to the outer solar system.

Given that similar surveys of other parts of the sky have failed to detect such an abundance of orbiting objects, it is worth asking whether they are simply unlucky, or whether there is something special about the solar system along New Horizons’ path, or whether The machine learning technology had some drawbacks that needed to be resolved.

The study results have not yet been peer-reviewed, and will then need to be confirmed by future ground-based and space-based research.

However, if we take it seriously, it is possible that our solar system contains at least two “rings” of icy material divided by a gap of about 50 AU; One consists of the familiar Kuiper Belt, and the other is a vast expanse of icy rock that extends as far away from Pluto as Pluto is from us.

Of course, why there is such a gap remains an interesting mystery.

This research was presented in 2023 54th Lunar and Planetary Sciences Conference.

By Mike McRae
Published on Science Alert