What happened

Virgin Galactic (NYSE:SPCE). Westport Fuel Systems (NASDAQ:WPRT). Plug Power (NASDAQ:PLUG).

What do a space tourism company, a maker of liquefied natural gas-powered truck engines, and a vertically integrated hydrogen fuel company have in common? Well, the latter two -- Westport and Plug -- are both broadly defined as alternative energy companies, and I suppose you could call Virgin Galactic an "alternative to NASA" space stock.

More importantly today, though, all three of these stocks are soaring on no apparent news. As of 11 a.m. EDT, shares of Virgin Galactic are gaining back 3.8% from last week's losses, Plug is tacking on 3.8% to last week's gains, and Westport is doing best of all -- powering ahead by a cool 10%.

Three colorful arrows racing straight up on a black background

Image source: Getty Images.

So what

These are impressive gains for three industrial "tech stocks" to be making on a day when the tech-heavy Nasdaq is down 1.3% -- and yet there appears to be no news behind the gains.

At best, you could say that Virgin Galactic stock might be bouncing back from an overreaction last week, when investors sold off the stock on news of another first-flight delay, combined with a big stock issuance to fund ongoing losses -- and that both Plug and Westport appear to be enjoying continued goodwill after their respective earnings beats last week.

Now what

But there's no new news driving today's gains -- a rebound from a possible overreaction, and a bit of continued momentum from good news a week ago, nothing more.  

All three stocks remain unprofitable tech companies with uncertain prospects. Until they begin generating sustained profits, I'd expect each to have as many "down" days as "up" ones.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.