Bitcoin topped $50,000 for the first time on Tuesday, doubling in value in less than two months.The digital currency traded as high as $50,584.85, before closing at $48,642.45, according to CoinDesk, up 0.95% for the day and 68% for the year, with a total market value in circulation close to $909 billion. The $50,000 level is an “emotional level for people in space,” said Brian Melville, head of strategy at trading firm Cumberland. But it is also a simple result of supply and demand, he added.From August through December, about 150,000 new bitcoins were minted, he estimated. The firm calculated that roughly 359,000 bitcoins were bought in the same period, and that imbalance has continued in 2021. “It’s a really important metric to watch,”he added. That buying demand has brought not only a price rally, but growing embrace and appreciation of an asset that was once an object of mockery for regulators and lawmakers.