The price of bitcoin is once again heading up on positive news and yet another Elon Musk tweet after the cryptocurrency hit six-month lows last week.

Last week, bitcoin hit a low of just above $31,000, its lowest level since January, but in the last 24 hours it broke through $40,000, a noted resistance level among traders.

The upward trend started in the middle of last week, but breaking $40,000 came on the same day that software company MicroStrategy Inc. announced that it has raised $500 million from a bond sale to purchase bitcoin. The Nasdaq-listed company, which dates back to 1989, offers business intelligence, mobile software and cloud-based services, but it has made regular headlines as a large investor in bitcoin.

MicroStrategy, which claims that “we are still early on bitcoin,” currently holds 92,079 bitcoin, worth more than $1.6 billion at the current price. According to The Block, using the money raised in the bond sale the company can now buy about 12,000 additional bitcoin, taking its holdings to more than 100,000.

Although significant investments in bitcoin can sometimes be controversial, MicroStrategy is said to have received more than $1.5 billion in orders for the offering. Investors also like what they saw, with the company’s share price closing up almost 16% in regular trading today, to $598.49.

More positive news came from Central America where El Salvador announced that it is adopting bitcoin as legal tender last week. The country also called for the use of geothermal energy for bitcoin mining in the country.

Returning to form, SpaceX Inc. and Tesla Inc. Chief Executive Officer Elon Musk once again may have played a role.

Responding to allegations from Magda Wierzycka, CEO of financial services company Sygnia Ltd. that his previous tweets about bitcoin were intentional price manipulation, Musk indicated that Tesla may accept bitcoin as a payment option again in the future. Notably, the price of bitcoin dropped in May after Musk announced Tesla would drop the option, citing environmental concerns.

“This is inaccurate. Tesla only sold ~10% of holdings to confirm BTC could be liquidated easily without moving market,” Musk wrote. “When there’s confirmation of reasonable (~50%) clean energy usage by miners with positive future trend, Tesla will resume allowing bitcoin transactions.”

Bitcoin was trading at $40,390 as of about 9 p.m. EDT, up more than 3% over the last 24 hours.

Image: QuoteInspector