It feels like the more we know, the more we realise how much we don't know. I think this is true of all knowledge. Take space exploration for example. Every now and then, we get to hear news that make us think, "How did we not know that till now?"

Granted, space is unimaginably vast and we know that there is just too much out there for us to have explored in any meaningful way already but when you hear news about something existing in our neighbourhood and us not knowing it, it really makes you wonder.

Recently, astronomers discovered an ancient galaxy orbiting our Milky Way galaxy. Yes, galaxies orbit other galaxies too just as our Moon orbits Earth and the Earth orbits the Sun.

This might seem like an entirely new discovery at first but we've known about several other satellite galaxies already. So, what makes this discovery special?

Things Are A Bit Odd

Astronomers were able to detect this satellite galaxy thanks to European Space Agency's Gaia satellite and have named it Antlia 2, located about 424,000 light years away. Although it is being labeled as a dwarf galaxy, it is by no means small in size, measuring roughly one-third the size of Milky Way.

As to why we are only now learning of its presence, the astronomers say that it was hidden behind the Milky Way's disc and is very, very dim, at around 10,000 times fainter than the Magellanic Cloud (another satellite galaxy).

Astronomers have speculated that this could be the remains of an ancient galaxy, which slowly lost its mass to the Milky Way's tides. But they find it really odd that Antilla 2 has a relatively larger size, without all that mass.

Matthew Walker, researcher at Carnegie Mellon University said, "We are wondering whether this galaxy is just the tip of an iceberg, and the Milky Way is surrounded by a large population of nearly invisible dwarfs similar to this one."

Space exploration just keeps getting more and more interesting.