Amateur and professional astronomers around the world are pointing telescopes at Jupiter to watch two huge storms graze one another as they race around the giant planet.

One storm, nearly as large as Earth, is battling with a much larger competitor, the mother of all Jovian storms, the planet's Great Red Spot.

The encounter was anticipated and announced to amateur astronomers earlier this month by the Association of Lunar and Planetary Observers. It began to get serious around Jan. 22 and was observed on that date by Clay Sherrod of the Arkansas Sky Observatory.

The whole interaction will continue for about two months, Sherrod told SPACE.com, though the timing is hard to predict.

Sherrod explained that the two storms are moving the same direction, with the smaller one, the white oval, travelling in a band of faster-moving clouds. Much of Jupiter's upper, visible atmosphere is marked by distinct bands of clouds that rotate at different paces, largely unchanged, for decades.

Now the white oval has caught the Great Red Spot and will soon overtake it. Already, though, some tugging and squishing is going on, as seen in images provided by Sherrod.

"We expect the oval to be slowed down at first," Sherrod said. "Then, on or about March 7, I expect it to be accelerated past the Great Red Spot and propelled eastward at an even faster rate for several months."

The white oval is no stranger to turmoil.

In 1975, Sherrod watched the same two storms interact. What happened? Surprisingly, the larger storm seemed to be more affected, fading in color for several years thereafter.

"It cost the Great Red Spot its red color for nearly three decades," Sherrod said.

This time around, he speculates the greater influence will again be on the larger storm. "We might see a bit of reddening and/or intensification of the Great Red Spot," he said. "Or, the smaller storm might fade."

He does not expect any dramatic long-term changes.

"These things have been around probably for centuries and originate deep within Jupiter from powerful vortex forces," he said. "This is likely not to affect them for long."

Glenn Orton, a senior research scientist at NASA's Jet Propulsion Laboratory, agrees with Sherrod that it's not possible to predict the outcome of the newest encounter. He also doubts that the white oval will be destroyed.

"The Great Red Spot has swallowed up storms in the past, but these were storms that were much closer to it in latitude," Orton said. "During the largest of these, the Great Red Spot ingested about half the area of the storm, with portions of the rest left circulating around its periphery and joining the flow of the external circulation."

There is one chance for greater drama.

As the edges of the two storms tickle each other over the next several weeks, it's possible that the white oval could become unstable and merge with the bright band of clouds in which it is embedded, Orton said. Such a process would take several days were it to occur.

Orton was careful to point out that the outcome and the timing are very much up in the air. Past brushes with the Great Red Spot have caused storms to speed up, stall out, or drift to new latitudes.

Orton and other astronomers will study the event to glean new information about how the atmosphere works on Jupiter, information that also helps meteorologists understand changes in the weather here.

Anyone can find Jupiter in the night sky. It's an easy target right now, being the brightest thing in the sky other than the Moon. Look high in the east after sunset. [See the sky map near the top-right of this page.]

If you have a pair of binoculars, train them on Jupiter and you should see up to four tiny points of light very near the planet. These are the four Galilean moons: Io, Europa, Ganymede and Callisto.

A good telescope will allow a view of the giant planet's cloud bands. The Great Red Spot, large as it is, requires some experience to find. It rotates into view, or "transits" the visible disk of the planet, every 9 hours and 55 minutes, Sherrod said.