I think I first encountered the story as a side note or passing mention in the context of destructive UFO encounters at least as far back as the early 1980's. I didn't pay it much mind, because it was a details-deficient bit of hand-waving analogous to what one gets on (e.g.) Ancient Astronauts.
I read at least two descriptions of the incident in the context of fatal backcountry / mountain trekking events no later than the mid-1990's. These accounts focused on the story in terms of bad luck or bad decision making, and only mentioned the more paranormal add-ons to illustrate how some others had spun the narrative.
The story was also familiar to me from mentions in one or more Usenet newsgroups in the pre-Web days. I believe the majority of these mentions were also in the context of UFO encounters.
Hi EG, I only came across the story about ten or so years ago, but have been spellbound by it ever since, and I know that i'm a bit late to the party on this thread [and have skipped virtually all of the previous posts for time constraint reasons , so excuse any unintentional duplication] but would like to post my current position on this brilliant mystery that has had me scratching my head for at least a decade...
After all of the hype that got me stuck into this case in the first place is near enough sided away as being capable to be explained mundanely, i.e the missing tongue and serious 'inexplicable-injuries' , the UFO, the radiation aspect etc. ... I still find at least one aspect of this great mystery totally enthralling, and that is what I believe to be the burning question about this tragic case...Why would they leave the tent?? And setting aside the popular speculations that the group were physically ousted from the relative safety of their tent... I would argue that the only thing that could make them leave would have to be an immediate thread inside the tent. if something was outside, such as an animal or a UFO, then there would be no reason to cut the tent open. There were no signs of an avalanche, however, they could have escaped believing an avalanche was tumbling towards them. The problem with that theory is that the footprints showed them walking in a calm and orderly manner down the slope as opposed to running away in panic. So something caused them to panic inside the tent but once outside they calmed down and made a conscious decision to walk down the slope. And in my humble opinion, the identity of the 'thing' that compelled this group of intelligent students to virtually commit suicide by destroying the integrity of their tent [aka, their lifeboat on the sea of frozen death] and marching relatively calmly to a certain agonizing death was something as simple as "Hysteria"! .. brought on by the consumption of narcotic toxins of some description. Throughout history the human race , especially true of the younger adult variety , have actively sought out and experimented in such hedonistic pursuits. So imho nothing too far fetched to contemplate in this theory. Something along the lines of LSD, which was ,I believe being invented by Swiss chemist Albert Hofmann in the late 30's and taken on by the CIA [MK Ultra] and other governmental bodies around the globe as well as being by the late 1950's the preferred 'mind enhancing tonic' by the super-cool beatniks and collegiate fraternity that sought out any mundanity-busting aids. Or then again the cause of this 'Hysteria' that I propose might just as easily be something more local than an illicit drug such as LSD being brought to the party by one or more of the hikers, indeed the region is known for it's own powerful hallucinogenic stimulant, and that is the renown very toxic fungus/shroom
'Fly Agaric', which the Mansi people in the area have gathered and cultivated throughout history to use for the purpose of getting high during their ceremonies, it should be taken into consideration that the fungus that I speak of is the very same product that the local Masnsi shaman often hang on lower branches of the pine's they were growing under to dry out before taking them back to the village. And the fact that their campsite and tent was pitched just a matter of yards from a pine forest seems to add a modicum of corroborative coincidence to this theory for me at least.
But of course that is just all conjecture coming from a guy that simply cannot know the truth of what happened that fateful night. But after a great deal of contemplation [wracking my tiny brain lol] the possibilities of this conundrum-ic case, first leaning one way and then switching direction etc over and over again, this speculative theory always seems to come around as the most likely to me.
And as for the second theory , well that is just as open to derision as the first, in relation to it's lack of tangible corroboration and is the identical causation of the flight from tent to the 'bad trip' hypothesis that I just mooted, .. yes 'Hysteria' again [or perhaps trepidation would be a better word]. This time facilitated by the [or at least someone within] Soviet Military. The source of this train of thought is that several facts of the case would seem to support the theory. For one , there are the numerous contemporary witness statements that clearly tell of an UFO being witnessed over the general Dyatlov-party area in the correct time frame. Secondly, the military's official denials of their presence in the region at any time , when it has been shown that the area had been and was a regular site for purposes of all kinds of military testing of new tech. [and the search party's recalling of seeing metallic debris over the area. And would explain a lot of the apparent governmental obfuscation and deliberate withholding of data, and summoning of the several different investigators to Moscow for instructions. My [maybe wild] estimation of what might have happened if this be the right track is that the Dyatlov party had unwittingly.. by means of deviating from their intended planned route.. stumbled upon a military testing of some new high tech vehicle, maybe as simple as a new helicopter or something? [ergo the UFO as seen from the many miles away that was the various vantage points of the eyewitnesses.].. and then [yes, still pure speculation.] you could make up your own scenario of what might have happened when a group of college hikers that weren't supposed to be there , gave the surprized soviet military unit a bit of a sudden jolt by being where there was supposed to be no-one! ... I'm thinking that a spot of heavy-handed scare tactics that got out of hand and ended in real tragedy might not be out of the question.
... I'll stretch my credibility no further and say no more about those two bits of speculation for now [probably said too much already. lol] And just say that imho at this point in time, that these are my best guesses as to what occurred on that fateful time, and that through the years of contemplation of this conundrum I have gone through the whole gamut of 'possibilities' that have been seriously touted.... UFO, Yeti, Mansi territorial murders, Semyon Alexandrovich Zolotaryov's spy connection, the Hikers being mistaken for escaped prisoners from a Gulag prison, the evil Mansi hunters theory, the popular spooked by avalanche suggestion, Infrasound, leaky stove, secret rocket launch, and a few that I can't remember right now.... and I can't promise that I won't go back to any of those [well some of them anyway] in the future, or that I may not even formulate another notion that seems to out-trump these two at any time,... but I have to say that for now at least these two seem the most feasible explanations for me. And please by all means, I always welcome alternative opinions.
This case has featured heavily on every paranormal site and in magazines for long since before I heard of it ten years ago, and there has been an awful lot of articles of various quality about it, [some downright weird ones] and I suspect that I have only seen a fraction of them, but if you are really interested in researching this fascinating case and are not already familiar with the facts of the occurrence [rather than wading through a lot of the more-sensational articles] then I recommend the following sites, where among many different references, theories and speculation [some quite sober, and some not so much?] you will find all of the available data on the case in one form or another for you to formulate your own conclusions...
https://dyatlovpass.com/updates
http://dyatlov.looo.ch/en/p/the-office-of-rauschenbach
http://forum.dyatlovpass.com/index.php?board=43.0
Cheers.