The far reaches of the Solar System are largely a mystery to humanity.
This region represents a sort of liminal interstice – an anti-Goldilocks zone too cold and too dark for both our close-range Solar System observatories and the powerful space telescopes with long-range vision that extends billions of light-years into space.
For many years, scientists have reconstructed the space beyond Pluto from breadcrumbs – scattered discoveries and indirect clues gleaned from the motion of those objects we have actually detected.
Now, the Vera C. Rubin Observatory is poised to blow it all wide open.
Researchers have just announced a spectacular new discovery – the telescope’s first candidate dwarf planet, a large object in the Kuiper Belt some 600 to 1,500 kilometers (373 to 932 miles) across.
Here’s the really amazing part. The object, named 2026 ED138, may have been right under our noses all along. Its entire orbit lies within Pluto’s range of distances from the Sun – yet we’ve only just discovered it.
And it may be one of the largest objects discovered yet in trans-Neptunian space, potentially reaching a size comparable to Makemake and Haumea.
“My first reaction was one of excited disbelief,” says astrophysicist Matthew Holman of the Harvard-Smithsonian Center for Astrophysics, who made the discovery.
“Objects like this are very rare, so I immediately started checking whether I or the code had done something wrong.”
Everything we have managed to learn so far about the Solar System beyond Neptune (about 30 astronomical units from the Sun) indicates that there’s a lot more out there than meets the eye.
In trans-Neptunian space lies the Kuiper Belt – a vast field of icy objects that extends out to about 55 astronomical units; and much farther beyond that, the hypothetical Oort Cloud, which may extend tens of thousands of astronomical units into space.
We’ve detected thousands of trans-Neptunian objects, from dwarf planets to small, icy bodies, while comets plunging toward the inner Solar System offer glimpses of material from even more distant regions.
However, directly observing the objects out there is extraordinarily difficult. At such enormous distances from the Sun, they receive very little sunlight to reflect, making them extremely faint at optical wavelengths. They’re also bitterly cold, emitting only a feeble thermal glow in the far infrared.
And they’re not stationary. As they travel around the Sun, their positions against the background stars gradually change. Unless a telescope is looking in the right place at the right time, an object can easily escape detection.
The final nail in the coffin is orbital misbehavior. The larger objects closer to the Sun orbit more or less in a flat plane – but beyond Neptune, things can get more chaotic. Many trans-Neptunian objects orbit the Sun at weird angles, dramatically expanding the area of sky astronomers need to search.This is where the Vera C. Rubin Observatory comes in.
Equipped with the largest digital camera ever built for astronomy, Rubin is designed to repeatedly survey enormous swathes of the southern sky, capturing objects too faint for many previous surveys to detect. (Yahoo News)