One of his rockets blew up, and he suffered a paper loss of about $390 million as the stock prices of two of his companies sank. Elon Musk was having a horrible day.
No one was injured in the explosion Thursday of the $62 million rocket owned by Musk's SpaceX, but the disaster set back the mission to place a satellite over the equator to expand communications in Europe, the Middle East and Africa.
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Shares of Musk's electric car maker, Tesla, fell 5.3 percent Thursday and were on pace for their worst week since Brexit. According to FactSet, Musk owns more than 31 million shares, making the billionaire's loss nearly $350 million for the day.
And at SolarCity, where Musk is chairman, shares were down 9.1 percent Thursday. He owns more than 22 million shares of the company, according to FactSet, making his daily loss almost $42 million as of the close.
With a decline of more than 6 percent so far this week, Tesla shares were tracking for their fifth-straight week of declines since their six-week losing streak ended Feb. 12.
Shares of Tesla lost nearly 10.4 percent the week ended June 24, when the surprise U.K. vote to leave the European Union triggered a global stock market sell-off.
Tesla year-to-date performance
The company announced Wednesday that it will raise more cash this year, through either a debt or equity offering, according to forms filed with the Securities and Exchange Commission. Tesla shares closed 0.3 percent higher.
Earlier this year, CEO Musk had warned of another "small equity capital raise," to fund both the development of Tesla's Model 3 car, and to build out its massive battery-making "gigafactory".
On Twitter on Thursday, Musk alluded to impending "major improvements" to Tesla's Autopilot system, which has come under fire this year after some owners crashed their cars while using the system.
Musk tweeted: "Major improvements to Autopilot coming with V8.0 and 8.1 software (std OTA update) primarily through advanced processing of radar signals"
Some analysts have accused Tesla of blowing through cash — Barclays analyst Brian Johnson has called the company a "lean, mean, cash-burning machine" in recent research notes.
Tesla has traded almost half it 30-day average volume of 2.85 million shares, trading 1.17 million shares so far today.
Meanwhile the company is going through with its $2.6 billion purchase of solar panel manufacturer SolarCity, which Musk chairs, and which counts two of Musk's cousins as top executives. The Wall Street Journal highlighted the financial struggles of both companies in a front-page article Thursday.
Analysts have divided opinions on the deal.
— CNBC's Gina Francolla contributed to this story.