CAPE CANAVERAL, Fla. - The International Space Station's inaugural crew greeted its first visitors Friday with handshakes, hugs and heartfelt thanks for a new $600 million power plant that now is providing ample electricity to the outpost.

Five days, 18 hours and 37 minutes after Endeavour docked at the station -- known by the radio call sign "Alpha" -- the shuttle's five astronauts coasted one by one into the outpost, toting still and video cameras to document the historic event.

Members of the Endeavour and Expedition One crews greet each other in the Unity module after opening the hatches between the shuttle and the station Friday.

On the other side of the hatch: U.S. astronaut Bill Shepherd and his two Russian cosmonaut colleagues -- Yuri Gidzenko and Sergei Krikalev -- who took up residence at the station Nov. 2.

Other than sparse radio contact, the station crew has remained isolated from other people ever since then, and the trio was obviously happy to meet up with their fellow space fliers.

Krikalev and Gidzenko greeted each with a handshake and a hug before the astronauts met a beaming Shepherd. All eight men then grouped up for a floating photo op.

"On behalf of the crew on Alpha, I'd like commend Endeavour and its crew for the tremendous technical challenge and the great achievement of putting [the power plant] together. We really appreciate it," station commander Shepherd said.

"I can't think of a mission that we've flown in a long time that's been a bigger challenge. It's been awesome."

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Launched Nov. 30, the shuttle crew arrived at the station two days later and then set out to erect a new five-story electrical power tower at the station.

Its most striking feature: a pair of giant, blue and gold solar arrays that now dwarf the station, stretching 240 feet (73 meters) from tip to tip -- a wingspan greater than that of a 747 jumbo jet.

Endeavour commander Brent Jett looks down through a small window in the space station's Zvezda module (top image) after boarding the outpost Friday. The view through that window is seen in the bottom image.

The Endeavour crew carried out three spacewalks to first mount the 17-ton power tower and then unfurl and activate its massive wings, which are capable of generating enough electricity to supply 30 average American homes (minus air conditioning).

Augmenting limited electric supplies generated by Russian solar arrays, the extra power is crucial to the outpost, its inhabitants and plans for future station construction.

Shepherd and company for more than a month were confined to two of three pressurized working areas at the station because there was not enough electricity to heat up the third.

That expansive room -- known as the U.S. Unity module -- was opened up Wednesday after electricity began flowing to it from the new solar wings. The additional power also will enable NASA to press ahead with plans to launch the station's first science lab next month.

The new electric tower can't be seen well from station windows, so the Alpha crew got its first first good look at the huge solar wings after floating over to Endeavour's flight deck and peering out overhead cockpit windows.

"They are pretty impressed with the arrays," shuttle skipper Brent Jett said.

"I can imagine," astronaut Shannon Lucid replied from NASA's Mission Control Center in Houston.

Then it was back over to Alpha. In keeping with the longstanding naval tradition of "ringing aboard" the commander of a visiting vessel, the station crew clanged a bell within the Unity module. A quick safety briefing and station tour followed.

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The first face-to-face meeting between the two crews was delayed until after the shuttle astronauts finished up their spacewalking construction work. The reason: Cabin air pressure aboard Endeavour needed to be kept much lower than that on the station to expedite preparations for each of the spacewalks.

The lower pressure reduces the amount of time astronauts must spend breathing pure oxygen to rid their bodies of nitrogen prior to a sortie into the deadly vacuum of space. The so-called "pre-breathing" procedure is critical to avoiding nasty bouts of decompression sickness, which scuba divers call "the bends."

Endeavour commander Brent Jett (left), Russian cosmonaut Sergei Krikalev and Expedition One commander Bill Shepherd are seen on the flight deck of the shuttle Friday.

The ceremonial hatch opening was a precursor to a full day's work aboard the station.

One of the top priorities: A 90-minute test that called for Endeavour crew to fire shuttle thrusters to see how the new wings reacted to the resulting forces imparted upon them.

As expected, the fragile wings wiggled back and forth just a bit but proved sturdy enough to endure the type of jet-firings routinely carried out to keep the station in its proper orbit.

Also high on the "to-do" list: taking out the trash at the station. Empty food and water containers, stowage bags, broken computer equipment and gear no longer needed aboard the station was hauled over to the shuttle for a return trip to Earth.

The so-called "transfer ops" will wrap up early Saturday before a farewell and hatch-closing ceremony that will be broadcast live on SPACE.com at 10:51 a.m. Eastern Standard Time (15:51 GMT).

Live coverage will continue as Endeavour pilot Mike Bloomfield backs the shuttle away from the station at 2:14 p.m. EST (19:14 GMT) and then guides the winged spaceship on a 45-minute "flyaround" of the station.

The camera-wielding shuttle astronauts are expected to beam back some of the most spectacular footage yet of the growing station during the looping cruise around the outpost.

Bloomfield will fire jet thrusters in a final separation burn at 3:17 p.m. EST (20:17 GMT) as the shuttle crew heads off on a two-day trip back to Kennedy Space Center. The Endeavour quintet remains scheduled to land here at 6:19 p.m. EST (23:19) GMT Monday.