Polaris Dawn launch fans gathering in Titusville Update 4:59 a.m.: FLORIDA TODAY Space Reporter Brooke Edwards reports launch spectators are gathering in Titusville at Space View Park-Veterans Memorial Park on the Indian River Lagoon shoreline. SpaceX Falcon 9 fueling now underway Update 4:51 a.m.: SpaceX just announced Falcon 9 fueling procedures are underway at KSC, and the Dragon's escape system is armed. That means tonight’s Starlink countdown is now committed to lift off at 5:23 a.m. without any delays, or else today's launch must be postponed. Polaris Dawn is 'go for launch' Update 4:40 a.m.: In a brief 4:38 a.m. tweet, SpaceX has confirmed: "Polaris Dawn is go for launch." SpaceX: Weather odds now 80% 'go for launch' Update 4:28 a.m.: Odds of favorable launch weather have now increased to 80%, SpaceX radio chatter indicates. The four Polaris Dawn crew members have been seated inside their Dragon spacecraft for roughly 3½ hours. Polaris Dawn officials released a selection of photos of the crew preparing for liftoff. SpaceX: Weather odds now 65% 'go for launch' Update 4:13 a.m.: In a change of atmospheric fortune, SpaceX webcast host Kate Tice said odds of favorable weather have jumped up to 65% for the upcoming 5:23 a.m. launch attempt. Crowds left Titusville parks after launch delay Update 4:04 a.m.: FLORIDA TODAY Space Reporter Brooke Edwards snapped this photo of illuminated pads 39A and 39B from across the Indian River Lagoon in Titusville shortly after SpaceX announced the nearly two-hour launch delay. Edwards said numerous spectators left Space View Park-Veterans Memorial Park after the liftoff time switched to 5:23 a.m. Clouds, rain encroaching Cape Canaveral Update 3:47 a.m.: National Weather Service radar from the Melbourne Orlando International Airport station shows a lingering cell of clouds and rain over KSC and the Merritt Island National Wildlife Refuge. SpaceX launch prep underway in Brevard Update 3:33 a.m.: Brevard County Emergency Management officials have activated the agency's launch operations support team ahead of SpaceX’s upcoming Polaris Dawn launch. Here's why SpaceX delayed 1st Polaris Dawn try Update 3:12 a.m.: SpaceX webcaster John Insprucker cited "dynamic conditions" as the meteorological reason the 3:38 a.m. liftoff attempt got pushed back. Insprucker said a shower was passing over the launch pad, but forecasters expected it to dissipate. "The bigger problem is, there are frontal boundaries north and south of the launch site — and we were then seeing cells popping up. And that made us a little concerned that they may still be around at T-0, and we would then have had to scrub for the day," Insprucker said. "So the good news is, we are still counting down for launch. We're going to wait two hours and change, and see how things go," he said. SpaceX pushes back launch to 5:23 a.m. Update 2:56 a.m.: SpaceX crews are now targeting liftoff at 5:23 a.m. — the first of two backup launch opportunities this morning — because of unfavorable weather. A cell to the northwest is of particular concern. Will clouds part for Polaris Dawn launch? Update 2:38 a.m.: This National Weather Service radar loop from the Melbourne Orlando International Airport station shows lingering shoreline cloud cover, stretching from Cape Canaveral and Merritt Island southward to roughly Sebastian Inlet. SpaceX radio chatter indicates officials will make a launch-weather decision 50 minutes before the 3:38 a.m. target liftoff time. SpaceX touts new spacesuits, upcoming spacewalk Update 2:25 a.m.: In a science fiction-esque tweet, SpaceX officials said the new spacesuits that Polaris Dawn will test in orbit feature "a scalable design with the intent to create millions to help make life multiplanetary." "Designed with mobility in mind, SpaceX teams incorporated new materials, fabrication processes, and novel joint designs to provide greater flexibility, while also incorporating enhancements for reliability and redundancy during a spacewalk," company officials said in a related 2:01 a.m. tweet. Polaris Dawn day-by-day schedule