The past few weeks have seen excitement turn to dismay for some shareholders in Space Exploration Technologies (NASDAQ: SPCX). The early surge in the SpaceX share price was replaced by a crash. Since the middle of June, it has fallen by 43%.

SpaceX is well known for its ability to bring rockets back down to earth fast after launching them – but investors would be hoping that the same did not happen to the company’s share price!

Still, could things get better from here?

A familiar-sounding story

Consider some of the risks investors see: an unproven business model, the need for huge capital expenditure, and doubt about how well the business might ultimately do in something of an unproven market.

We saw those same elements at the time another business led by SpaceX’s boss was floated on NASDAQ: Tesla.

So, if SpaceX does as well in the next 16 years as Tesla has done in the 16 since its 2010 stock market listing, what would that mean for the rocket company’s share price?

So far this year, Tesla stock is down by 28%.

That does not sound encouraging. But this is where being a long-term investor can show its value as an approach.

Over the 16 years since it launched, the Tesla stock price has grown by 25,063%. In other words, $1,000 invested back then would now be worth over a quarter of a million dollars.

If SpaceX was to do as well in the coming 16 years, what would that mean for its share price?

Currently, it stands at around $115 apiece. If it went up by 25,063%, we would be looking at a 2042 price of around $28,937 per share.

Is this a useful comparison or not?

On one hand, this might seem like irrelevant information, for two reasons.

First, Tesla and SpaceX are separate businesses in different areas.

Secondly, past performance is not necessarily an indication of what to expect in future – as Tesla’s stock price fall this year itself demonstrates.

But not so fast! While the comparison has clear limitations, I still think it is potentially useful for one key reason.

It demonstrates that a business that is losing money, cash-hungry, and largely unproven can nonetheless power on and create enormous wealth for long-term shareholders.

So, should I buy?

Could it therefore be worth adding some SpaceX stock to my portfolio?

Potentially, yes. The company is growing fast, it has a large customer base, benefits from proprietary technology, and has a massive, growing addressable market.

If it does well enough, I think the share price could soar in the coming 16 years.

As an investor, though, I aim to balance risk and rewards carefully. While I see the potential for SpaceX’s share price to soar, I also see lots of risks.

Competition is growing daily, the company faces complex geopolitical risks, and it may need to spend huge sums of money even to try and fulfil its potential.

At the current share price, SpaceX simply looks too expensive for my tastes.

For now, I will be looking elsewhere in the market for brilliant growth stocks I think offer much more compelling valuations.

Should you invest £5,000 in SpaceX right now?

When investing expert Mark Rogers and his team have a stock tip, it can pay to listen. After all, the flagship Twelfth Magpie Share Advisor newsletter he has run for nearly a decade has provided thousands of paying members with top stock recommendations from the UK and US markets.

And right now, Mark thinks there are 6 standout stocks that investors should consider buying. Want to see if SpaceX made the list?

Christopher Ruane does not hold any positions in the companies mentioned.