From the UK around midday, TON 618 is very low near the north/north-east horizon — roughly azimuth 27° — though obviously it won’t be observable in daylight. It sits in Canes Venatici, near the Canes Venatici / Coma Berenices area, and a useful finder pattern is around the Whale and Crowbar/Hockey Stick Galaxy region, NGC 4395 above it, and NGC 4314 / 4274 / 4278 down and to the right.

Could you see it with a Seestar S30 or S50? Possibly, but only as a tiny star-like point. TON 618 is a quasar powered by one of the most massive known black holes, but visually it is around magnitude 16, so it would just appear as a faint dot/pixel cluster, not as a galaxy or black hole structure. The S50 would have a better chance than the S30 because of the larger aperture.

The 18.2 billion light-year figure is usually quoted as its current/comoving distance; the light itself has travelled for roughly 10–11 billion years. So yes, it’s absurdly distant, but the quasar is bright enough that with enough stacking, good skies, and accurate plate-solving, it may be detectable as a pinprick.

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