Bitcoin has surged to $90,000, driven primarily by technical indicators rather than new market catalysts. Analysts from Presto Research and Kronos Research highlighted that the price movement was likely fueled by short covering and momentum buying, as well as a rebound from a key support level following a period of consolidation. Additionally, Bitrue's Andri Fauzan Adziima noted that relief from options expirations and correlations with altcoins contributed to the price increase. Despite these gains, over $1 billion in ETF outflows have kept Bitcoin trading within a range of $86,500 to $90,000 throughout December.