The countdown has begun for the $1.75 trillion (£1.3 trillion) flotation of SpaceX – Elon Musk's rocket, satellite and artificial intelligence (AI) company.This behemoth could be launched on to the US stock market as early as June 12, and excitement is spreading to other companies in this industry.The frenzy is boosted by SpaceX's claim the global market for space technologies could be worth as much as $28.3 trillion.One indicator of the confidence in the future of space stocks is the soaring performance of shares in investment trust Seraphim Space, which backs US, European and UK space companies and is due to join the FTSE 250 next Tuesday.Seraphim does not invest in SpaceX, but manager Mark Boggett says its flotation represents 'a powerful validation of space not just as a frontier, but as critical economic infrastructure'.Despite such insights, you may still be sceptical. After all, SpaceX's plans involve the construction of data centres in space and powered by the sun (somewhat sci-fi, but almost certainly deliverable) and the colonisation of Mars (rather trickier to implement). Reaching for the stars: SpaceX could be launched on to the US stock market as early as June 12The investor roadshow, which begins on June 4, should spell out the company's goals – both commercial and interplanetary.There will also be guidance on how private investors can apply for shares with 30 per cent of the sale reserved for them, far more than is usual.Meanwhile, the interest in other space stocks is forecast to grow. If an extra-terrestrial foray is your summer investor adventure, here are the names to explore – and the way to secure a slice of SpaceX before the sale. Looking ahead: SpaceX boss Elon MuskSPACE RACE CONTENDERSAmid the SpaceX buzz – and boosted by new Nasa plans for communities on the Moon – US, European and British space companies are in demand. Many play a key role in defence, with systems that can also protect Earth's environment.The S&P Kensho Final Frontiers index, which tracks US aerospace, satellite and related businesses, has surged by 47 per cent since January. Heading for the stratosphere has been Rocket Lab, whose price is 102 per cent higher than at the start of the year, thanks to the perception that this Californian business is, albeit much smaller, a SpaceX rival. Since January, shares in US satellite imagery provider Planet Labs have jumped by 147 per cent to $49.European space players are also on a thrill ride. OHB, the German satellite operator, has risen by 279 per cent to €443 since January. SES, another satellite operator but Luxembourg-based, has bounced by 70 per cent in the same period, too. Meanwhile, the price of Filtronic, a British supplier of satellite communication components, has leapt by 115 per cent to 390p. SpaceX has a 15 per cent slice in the business.Also moving upwards has been EutelSat. Since January, the French satellite group's shares are up by 133 per cent to €3.98 thanks to its status as a competitor to Starlink – SpaceX's internet division.EutelSat owns OneWeb, a British firm with which it merged in 2023. The Government controls 11 per cent of OneWeb's shares and has an additional golden share, having bailed out the firm in 2020.Some of the biggest space businesses remain private, but you can gain access to them through Seraphim Space. Among the trust's largest holdings are ICEYE, a Finnish satellite manufacturer, and D-Orbit, an Italian space logistics company.Seraphim's shares have surged 79 per cent since the trust featured in this column in March as a route to participate in space exploration and innovation. I followed my own advice and will stay on board,hoping for more fun, but also acknowledging the risks. If SpaceX shares dazzle briefly before losing their lustre, this could cast a shadow over other space stocks.