July 12 (Reuters) - British billionaire Richard Branson has bought a stake in space tech fund Seraphim Space Investment Trust (IPO-SERA.L) as part of a 178 million-pound ($246.99 million) initial public offering, London-based Seraphim said on Monday. Airbus SE (AIR.PA) also participated in the IPO and was among other parties to buy shares of the company, according to an emailed statement by Seraphim, which is set to commence trading this week on the main market of the London Stock Exchange. The exact amount of those stakes was not disclosed by Seraphim. Bloomberg reported earlier on Monday that Branson had purchased stock in London-based Seraphim in a sale that closed on Friday. ($1 = 0.7207 pounds)