Beyond this, the Universe is really big and under no obligation to preserve our sanity. Ask an FTL navigator if you wish. In the Sandoval stories non-biological entities are an established fact. They are composed of exotic matter, drain heat or electrical energy for food and can get a decent idea of what scares you and use it to drive you away. Doubtless as we move further into the Dark we will encounter things that make NBEs seem like 'Hello Kitty'.
Then you have some folks who just like a good ghost story and will maintain it no matter how much evidence there is t the contrary or at least lack of proof. They will truthfully declare that people have reported such things for millennia. In fact, odds are the Cro-magnon sat in front of scary paintings on dark nights and thrilled to them.
Not to mention some people out and out lie for various reasons.
Ships cost tens of millions of dollars and are a steady source of income. A bank watches credit signs and won't pay attention to weird reports. At worst they'll slap a new coat of paint on a haunted hulk and put it back on the market. Similarly, there are many good reasons for a crew not to abandon ship ("I don't care if the bulkheads are bleeding and bugs are crawling out of the USB ports! Any rescue is weeks away!") Bugs crawling out the USB port is a hardware problem should you seek tech support.
Nevertheless some crew abandon ship (law of averages again) or are killed outright. Again a ship is worth tens of millions of credits. So the natural impulse to use a 'cursed' ship for target practice is often ignored. Even if no crew wants to set foot on its deck a ship has value, it's a ta write off for one thing. It is a source of salvage for another. Salvage crews are often mobile and will have no idea of a ship's bad rep.
Ghost ships are kept handy but not too handy. They get relegated to -you guessed it- a Sargasso. Where you have a Sargasso, you will have ghost ships. That's been the pattern through out settled space and into the fringes.
Some enterprising Sargasso dwellers even run tours of infamous ships to ground pounders on a space holiday. The way money disappears from your pockets on these tours could be considered supernatural by some.
Ghost ships in the wild are another case entirely. Ships that move around but do not answer hails, are way colder than they should be, or have other anomalous readings do happen. Contrary to popular movies free traders do not usually board such ships in search of adventure -or- loot. It may be a pirate trick. It may be a ship with dangerous or even deadly conditions onboard. It might be a fricking haunted ship!
A remastered ghost ship for your SF game: the Icon Messier*
The Icon Messier was a naval auxiliary ship based in a well settled system. Substantial assets on various moons and planets needed defending and the system navy had a number of remote bases and defense systems the Messier was assigned to resupply. On her maiden voyage the Messier had to resupply a base in the outer system and faced a cruise of a few weeks. The first day out some crew had an uneasy feeling. Around third watch this foreboding turned to anxiety in some. By midnight a riot broke out with crew assaulting each other. The ship's officers attempted to restore order with gas and tranq rounds until a crewman fell through a hatch and broke his neck. The madness stopped then.
The Messier crew was calm for the next few days until a deckhand reported seeing a faintly glowing humanoid figure in the main hold. The figure walked behind a large crate and vanished. The antihijack program recorded a glowing orb that might be a video malfunction or dust mote. That night the madness repeated. The crew again rioted. This lasted until another crewman was killed by the mob. The captain ordered both bodies ejected into space, fearing the madness was caused by a pathogen. Oddly crew thought they saw the bodies following several times and the captain ordered the portholes sealed.
There was one more eruption of madness despite the crew being confined to quarters off duty. It started with the steward killing himself in the galley. By the time the ship reached its destination the entire crew except for the bosun debarked and refused to return despite threats of jail and violence. The base commander made the bosun acting captain and found some drifters and day workers to crew the Icon Messier (with fat bonuses). The ship headed out again for another remote base.
The new skipper committed suicide the second day out. The pattern of madness repeated itself three times on the voyage and the crew abandoned ship as soon as they could trust the SAR from the base to pick them up in their spacesuits. The Icon Messier was towed into orbit. At this point no crew would look at the ship, so it remained in orbit. A few weeks later sensors recorded a burst of thermal activity onboard indicating a fire. An SAR ship was dispatched to control the fire. As a precaution the search and rescue performed a hail to make sure the ship was indeed abandoned. The ship's radio transmitted a horrific scream that might be a malfunctioning auto distress call. The SAR ship was closing when several explosions occurred on the ship.
The SAR captain aborted the mission. The Icon Messier's burnt hulk was used for target practice on the next training mission. Stories persist that several cargo containers were thrown free of the explosion somehow and ended up drifting in space and that several parts or items were salvaged from the ship. Vessels that used or merely transported them had 'interesting' stories to tell. The hard science explanation for the madness was hysteria compounded by subsonic vibrations or electrical fields caused by malfunctioning machinery.
But where's the fun in that?
*Okay Icon Messier is