Resist the urge to high-five everyone in the cubicles next to you. Your stock may have just strapped on a rocket pack and taken off for the moon, but smart investors won't celebrate until they know that upward leap was justified. Without a fundamental basis for the bounce, these stocks can quickly make the return trip down.

Is now the time to lock in profits, or is this just the first step toward even higher valuations down the road? Let's examine several stocks that just hit the afterburners, and see whether they're truly headed into orbit.

Stock

CAPS Rating (out of 5)

Past Week's Change

KV Pharmaceuticals (NYSE: KV-A)

**

108.76%

Emcore (Nasdaq: EMKR)

**

37.70%

Timberland (NYSE: TBL)

***

33.89%

Although it may have felt like two steps forward, one step back at times, the market has risen more than 1% over the past week, as the market ignore rising inflation and higher jobless claims, preferring instead to focus on an ebullient manufacturing report. So stocks that have surged upwards by larger percentages are even bigger deals.

New frontiers in investing
With its stock soaring after FDA approval for its drug designed to reduce the risk of preterm birth, KV Pharmaceuticals figures it's a good time to raise some cash. The biotech will be raising $32 million in a private placement and will be setting up a $130 million financing facility, too. The funds it receives from the stock sale will be used in part to launch the drug Makena.

Under development with Hologic (Nasdaq: HOLX) and previously known as Gestiva, Makena is designed to reduce the risk of premature birth in women who have a history of preterm birth. It was only a month ago that analysts were wondering whether KV could survive financially after the FDA delayed a decision on the drug. It came back quickly, however, with an approval and KV's stock has been on a tear since, up 420% this month alone (and it's up another 10% as of this writing). It's doubtful it will remain hidden from Wall Street's sight much longer.

Whatever the merits of the treatment, the sudden surge in price has CAPS All-Star EnigmaDude thinking the stock has come too far, too fast and is ready for a fall. But the wider CAPS community is looking for the stock to outperform the broad market averages with 92% of the more than 400 members rating the biotech giving it the thumbs up.

You can add your own opinion on the KV Pharmaceuticals CAPS page on whether you think EnigmaDude is premature in calling for it to return to earth.

Making it to the big time
Although Emcore isn't ripping as high as KV, the optical networking specialist is enjoying the updraft from a superb first quarter earnings report. Revenues jumped 23% higher generating a 36% increase in profits as its photovoltaic segment saw greater sales sequentially and year over year and wider margins. Even rival JDS Uniphase (Nasdaq: JDSU) is seeing the value in the solar sector as it branches out from the telecommunications market, and its shares are higher, too.

It's a rising tide that's lifting all boats, with Emcore, Ciena (Nasdaq: CIEN), and Finisar all rallying higher. Yet Emcore also reported that its PV backlog was down 32% as it completed several projects and experienced a delay in a new order from an international customer. Look to its concentrating photovoltaic (CPV) joint venture, though, as it begins to gain traction.

Follow along with EMCORE by adding the stock to your watchlist and have all the Foolish news and analysis gathered together for you in one place.

The sky's the limit
Boot maker Timberland was another company kicking analysts' butt with its most recent quarterly report, with earnings that more than doubled over the year-ago period. While Wall Street was shocked -- shocked! -- that a simple footwear company could produce enormous growth, the Fool's Alyce Lomax had chosen Timberland as her inaugural pick for her Rising Stars portfolio.

While the run-up in the stock gives it a pretty hefty market premium, compared to similar situated Deckers Outdoor (Nasdaq: DECK) it is priced right in line with its peer. Wolverine Worldwide, however, with equally impressive quarterly results, seems downright cheap at just 17 times trailing earnings and a multiple below 14 times forward estimates.

What sets Timberland apart for CAPS member gweech is that its shoes bundles both functionality and style:

Solid company and solid products. TBL shoes last forever and ever and ever. The US will always have an athletic outdoor bent to it and people will always buy this clothing at stores like REI. Unlike pure designer brands, TBL has both utility and fashion built into one package.

Walk over to the Timberland CAPS page and let us now whether it's time to give it the boot from our portfolio after this big run, or should we be adding more?

Going into orbit
That's why it pays to start your own research on these stocks onĀ Motley Fool CAPS, where you can read a company's financial reports, scrutinize key data and charts, and examine the comments your fellow investors have made, all from the stock's CAPS page. Then you can decide for yourself whether your stock's headed for reentry, or off to infinity and beyond.