At the far reaches of the Solar System, past Neptune’s orbit, things are beginning to look trickier and trickier to see. Directly imaging small objects in the darkness of the Kuiper Belt – where Pluto lives – is really difficult, making a recent discovery all the more exciting.
If you know where something is, you can observe it by waiting for it to pass in front of distant stars. This is called occultation, and astronomers use it to study all kinds of trans-Neptunian objects.
But when astronomers used the occasion in 2018 to study something they had been watching for nearly two decades, they found something really unexpected – a chonk of a month, related to this body is orbiting. A study describing their findings has now been accepted Astronomy and Astrophysics, and first covered by Jonathan O̵7;Callaghan in New Scientist.
The thing that caught the sport this month may be the dwarf planet (84522) 2002 TC302. It was first discovered in 2002, after which it was also identified in earlier observations.
Between 2000 and 2018, astronomers collected at least 126 object observations at various wavelengths (including the Hubble Space Telescope); using this information, they calculate the potential size, size, and color of the dwarf planet.
They found that it was about 584 kilometers (363 miles) wide, and had an orbital period of 417 years – in a 2: 5 orbital resonance with Neptune.
That is awesome. It means 2002 TC302 almost meets the requirements for a dwarf planet – it’s in orbit around the Sun (but not another planet); it did not clear the neighborhood of this orbit; and it must have sufficient mass to achieve hydrostatic equilibrium, or a circular shape.
But we’re not sure. When predictions of its orbit point to an event event on 28 January 2018, observers across Europe pointed their eyes to the 2002 TC302neighborhood to try and find out its physical properties, such as size and shape.
Telescopes in Italy, France, Slovenia and Switzerland made 12 positive detection events at the event, as well as four negative departures. This made the best observation of a trans-Neptunian object we have acquired so far, the researchers said.
Adding these allowed researchers to obtain a new, more accurate measurement of object diameter: 500 kilometers (311 miles).
So, how do you account for the missing 84 kilometers calculated from other observations? Well, there’s a really interesting answer to that. If 2002 TC302 having a moon around 200 kilometers (124 miles) wide, and 2,000 kilometers (1,243 miles) from the probable dwarf planet, it could signal that other astronomers interpret it as a slightly larger 2002 TC302.
It’s crazy close by. The Moon, for context, is 384,400 kilometers (238,900 miles) from Earth (on average). So far, 2002 TC302The satellite will be a very difficult image – even if the Hubble Space Telescope images taken in 2005 resolve it one at a time.
If the potential dwarf planet actually has satellites, it will help us to know things about the early Solar System. The ingredients in the Kuiper Belt have changed a bit since the Solar System was formed, and as such, these things are considered time capsules.
Two things that will work together will help us better understand the close relationships that formed the Solar System. Because planets are thought to be formed by climbing – more and more objects are attached – this can be an important indicator of how small bodies grow.
One thing of mutual interest is Arrokoth, the odd-shaped snowman that was visited by the New Horizons probe in 2015. The data provided by this flyby showed us that planetary accretion may be a more subtle process than we thought. .
2002 TC302 is bigger than Arrokoth, but it can be in another phase of the process – which is really helpful in combining the stages in which it occurs. At any rate, obviously we should look at it a little more and try to figure out what it is dealing with. Exciting!
The research was accepted into Astronomy and Astrophysics, and is available on arXiv.