Michael Race
Business and economics reporter

SpaceX's listing on the technology-focused Nasdaq index is as a test case in the valuation of AI companies going public and will be closely watched by rivals.

Musk's company is the first of three AI-related mega-listings expected this year, with OpenAI and Anthropic set to follow suit.

The quantities of cash being piled into AI companies in recent years - which have posted heavy losses to date - has led to some claims companies are being overvalued and that there is an a "AI bubble", which could burst.

Such a financial earthquake would send ripples across the world, rocking stock markets and bankrupting companies.

The Bank of England has sounded alarm over a "sharp correction" in the value of AI companies, while Jamie Dimon, boss of US bank JP Morgan, has admitted some of the money being invested in AI will "probably be lost".

But a big part of the demand for SpaceX shares will be investors not wanting to miss out on the potential riches AI could bring. It's a bet on what the companies plan and could achieve and how their technology could be developed in the future.

Archie Mitchell
Business reporter

Image source, Reuters

Elon Musk’s SpaceX is expected to begin trading on the Nasdaq stock exchange at $171 per share, significantly higher than its $135 per share initial offering price.

The increase, driven by bumper demand for exposure to the space and AI company, would give it a market value of $2.2tn, and comfortably cement Musk’s position as the world’s first trillionaire.

The share price expectation was reported by Reuters.

Lucy Hooker
Business reporter

Image source, AFP via Getty Images

Anyone trying to predict the future path of SpaceX shares – whether up or down - has a huge range of conflicting forces to consider.

Musk’s celebrity status, and loyal online following, not to mention the hoopla around the sheer size of this IPO, is likely to boost demand for the shares.

But Musk’s notoriety, his sometimes erratic behaviour and controversial public statements, also carry some risk, especially as the way voting rights are distributed, means he remains in firm control.

The scale of ambition – putting a million people on Mars – and the range of activities, from re-usable rockets to AI data-centres on satellites – will attract some investors.

But there is plenty of scepticism too: are these plans realistic?

To top it all, SpaceX isn’t currently making a profit. And the IPO prospectus admits it "may not achieve profitability in the future".

Image source, Reuters

Moments before SpaceX began trading in New York, founder and CEO Elon Musk had opening remarks from the company's base in Texas.

"It is certainly hard to believe a little company that started in a warehouse in El Segundo is now going public with the largest IPO ever," Musk says.

"I gave SpaceX less than a 10% chance of succeeding at all," he adds.

He reiterated the company's vision of human life in space.

"We want to be able take anyone who wants to go to the Moon, anyone who wants to go to Mars, or anywhere in the solar system... I am confident at this point that with the incredible team that we have here at SpaceX that we will do that for you."

Musk pushed the button to officially begin trading from Texas, which was followed by confetti and a loop of Elton John's 1972 song "Rocket Man" playing in the background.

It's now 09:30 ET, which means the Nasdaq stock exchange is officially open for the day.

That means SpaceX stock is, for the first time, now available for public purchase.

We'll be bringing you the latest updates from the stock market, along with analysis from our correspondents. Stick with us.

Image source, Reuters

Shanaz Musafer
Business reporter

Image source, Peta Cooper

Peta Cooper, 43, a copywriter who lives in Cornwall on the south coast of England, is one of those planning to buy SpaceX shares when they start trading today.

Cooper, who grew up in California and who already has a portfolio of shares mainly in tech and crypto firms, plans to invest about £750.

"It's really exciting. I really love the space industry. [SpaceX] have had a really great track record so far with their launches and their innovation," she says.

While she expects the share price to dip at some point, she plans to hold onto the stock in the long term.

"I plan to keep it in my portfolio and let it grow."

Archie Mitchell
Business reporter

Shares in SpaceX are on course to surge by more than a third when markets open in the US, according to trading in products designed to track the company’s value.

Investment platform IG is offering derivatives allowing investors to bet on the anticipated value of the company when trading begins.

Trading on IG International would point to a 35% surge, or pop, in SpaceX's value when trading begins, taking its market value from $1.77tn (£1.3tn) to $2.4tn.

Lily Jamali
North America Technology Correspondent

Ahead of the IPO, some SpaceX critics raised concerns about potential rule changes made by major stock market indexes.

Chief among them: US Senator Elizabeth Warren, the highest-ranking democrat on the Senate Banking Committee. In a letter sent this week, she said she was worried that these indexes were “being rigged” in a way that would force millions of investors in passive index funds “to invest in SpaceX and face exposure” without any choice in the matter.

The Nasdaq-100 index is the most prominent example of a change made ahead of SpaceX’s debut. Last month, the index agreed to allow mega IPOs like SpaceX to be fast-tracked onto the index after just 15 trading days instead of the usual waiting period which can run up to one year.

The S&P 500, on the other hand, declined to allow such fast-tracking onto its index or change other rules including the requirement that new entries be profitable before joining. SpaceX posted losses last year and in the first quarter of this year.

Daniel Thomas
Business reporter

It looks very likely. Musk - who is already the world’s richest person - derives most of his wealth from his large ownership stakes in Tesla, his electric car business, and SpaceX.

If SpaceX shares begin trading at the offer price of $135 (£100) on Friday, then the company's market value would climb to nearly $1.8 trillion, pushing Musk's personal fortune above $1tn.

However, if SpaceX trades below $135, or there is a sharp and unexpected drop in Musk’s Tesla holdings, the milestone may be missed.

Right now he’s extremely close: on Thursday, the Bloomberg Billionaires Index - which lists the world’s richest people - estimated Musk’s net worth to be $971bn.

Jemma Crew
Business reporter

Image source, Bloomberg via Getty Images

Earlier today, before US markets opened, SpaceX chief operating officer Gwynne Shotwell told CNBC she hadn't been sure the company would go public, but it "feels like the right time now".

"We've been feeling over the last few years a lot of pressure from everyday Americans and our friends that wanted to buy stock," she told the US business news network.

In the interview, Shotwell said SpaceX has long-term ambitions and she doesn't want to focus on quarterly results.

"I'm not saying we're not going to do right by our investors, but what folks that invest in SpaceX need to know... is that what we're doing is very futuristic."

She was also asked about SpaceX's governance structure. Musk will maintain almost total control - his shares come with extra voting rights meaning he effectively controls 85% of the company.

"There is no-one who can run this company other than Elon, frankly. We want Elon to have that kind of control," she replied.

Michael Race
Business and economics reporter

The level of hype surrounding the listing of SpaceX has been like no other IPO before and perhaps it's not surprising.

The rare move by the company to set what it thought the share price should be well in advance last week was perhaps part of the plan in maximising interest.

In central London this week, I saw a giant electronic billboard outside a shopping centre advertising to the general public that shares were going on sale. On the flipside, there have been posters put up in bus stops by activists highlighting Musk's wealth and how many people in the world don't have access to safe drinking water.

Various investment platforms here in the UK have offered their services to enable individuals to get in on the action. It's expected this might be the first dabble in investing for many.

However, some analysts have urged caution and raised concerns that the company is overvalued. The share price could rise or fall following the start of trading and the financial health of the company going forward will influence it as well.

To be clear - no one can be 100% certain what will happen after the bell rings on Wall Street. It's all one big bet.

Image source, Getty Images

Simon Jack
Business editor

After trading starts at 0930 in New York - 1430 UK time - it may take several hours for the price at which shares are trading in real time to become visible.

This is because market participants will have to match large numbers of buy and sell orders through an auction-like process.

Given heavy demand and limited supply - just over 4% of SpaceX shares are up for sale - it is very likely that the shares will show a considerable rise (pop) at first.

The real test for demand will come over the next year as existing shareholders are able to sell additional shares into the market as restrictions on them selling (lock-ups) are lifted in a staggered way after key earnings announcements and share price targets are achieved.

Michael Race
Business and economics reporter

Hello and welcome to our live coverage of SpaceX's launch - excuse the pun - on the US stock market in about an hour's time.

The hype has been building ahead of the largest public share listing in history, which will see Elon Musk's rocket and AI company go public and potentially make the tech tycoon a trillionaire.

We will bring you the latest news and analysis as it happens.