Comets show up all the time and are observed by telescope. The rarity is of “naked eye visible” comets. My personal experience is that they show up about once per decade (click here).
I was due for another comet and it has shown up.
The media are incorrectly calling it “Comet Atlas”. Search for that name and about three dozen comets will pop up because ATLAS is the acronym for the name of the observing system that discovered it, not that of the comet itself. The Asteroid Terrestrial-impact Last Alert System is – as the name reveals – a project to find asteroids. It does occasionally discover a comet and it finds thousands of supernovas – in other galaxies – none are even close to “naked-eye objects”.
As most nerdy people know, comets frequently defy prediction and disappoint millions of viewers. Thus far, Comet 2019 Y4 has only defied prediction by rapidly brightening far in excess of prediction. Please see graphic below.
The green line plots the predicted brightness. Points in blue are from actual observations. Note that this comet has grown to near naked eye visibility (from a dark sky, not in city lights).
Where to see this? A screen grab of a sky map from Heavens-Above.com for 3/25 to 3/27 (with text and markings by your humble narrator to “Un-nerd” same) appears below.
Update: I tried, unsuccessfully, to see this comet with binoculars – in glaringly lit-up Houston skies on March 24. The latest brightness observed (by professionals) is Mag. 7.6 as of 3/25. But, it will get brighter, soon.
Update: No luck on the 25th, either.
That Heavens-Above.com map is at the link below: