The U.S. military's new space surveillance observatory has begun maneuvering toward its operational perch to track orbital objects without the hindrances imposed on ground-based monitors.

Read our full story.

Leaving behind the earthly limitations imposed on reconnoitering space, a telescope-laden sleuth was launched Saturday night to survey the dangers of orbital debris and monitor nefarious threats against vital national security satellites.

Read our full story.

8:40 a.m. local (11:40 a.m. EDT)
We've posted another photo gallery with launch pictures from sound-activated cameras at the pad.
1:55 a.m. local (4:55 a.m. EDT)
The SBSS has deployed its solar arrays, oriented them at the Sun and initialized operations. Officials report the satellite is healthy.

Here's some post-launch comments from the Ball and Boeing contractors:

"The successful launch of SBSS is an important milestone to ensure that this nation's assets are protected," said David L. Taylor, president and CEO of Ball Aerospace. "We are proud to be a leader in providing critical technology development to the Air Force's space situational awareness mission."

"The United States depends on space assets for security, communications, weather forecasting, and many other essential services," said Craig Cooning, vice president and general manager, Boeing Space & Intelligence Systems. "America's adversaries recognize this increasing dependence, which makes the need for enhanced space situational awareness more and more vital. Today, the Air Force and Boeing SBSS team are delivering this advanced capability to the nation."

1:40 a.m. local (4:40 a.m. EDT)
"Our mission this evening was a tremendous success. After all of the long days and long hours that prepared us for this important event, the team performed flawlessly. Thanks to all for their hard work and dedication to mission success, always our number one priority. The team will now work to initialize the spacecraft and complete a comprehensive testing period before transitioning to full time operations early next year," said Col. J.R. Jordan, SBSS mission director.

"The nominal launch of the Minotaur 4 space launch vehicle did what it was designed to do," said Lt. Col. Kent Nickle, deputy mission director for the launch. "As a representative of the Space Development and Test Wing at Kirtland Air Force Base, I am proud to be a part of such an important mission for space situational awareness. A well deserved congratulation goes out to the entire team for a mission well done."

1:00 a.m. local (4:00 a.m. EDT)
Leaving behind the earthly limitations imposed on reconnoitering space, a telescope-laden sleuth was launched Saturday night to survey the dangers of orbital debris and monitor nefarious threats against vital national security satellites.

Read our full story.

10:25 p.m. local (1:25 a.m. EDT)
Post-launch quotes from Col. Richard Boltz, Vandenberg Air Force Base's 30th Space Wing commander:

"SBSS will greatly enhance our existing space situational awareness capability, a capability vital to protecting our space-based assets," said Colonel Boltz. "This evening's launch was our third launch in eight days, and I am extremely proud of Team Vandenberg for all the hard work and dedication they've put into these important missions."

10:22 p.m. local (1:22 a.m. EDT)
Absolutely spectacular pictures of the Minotaur 4 rocket are posted.
9:57 p.m. local (12:57 a.m. EDT)
The rocket successfully achieved a great orbit with an apogee of 541 km, perigee of 538 km and inclination of 97.99 degrees.
9:55 p.m. local (12:55 a.m. EDT)
T+plus 14 minutes, 50 seconds. SPACECRAFT SEPARATION! The Air Force's Space Base Space Surveillance satellite has been released by the Minotaur 4 rocket, completing tonight's launch!
9:54 p.m. local (12:54 a.m. EDT)
T+plus 13 minutes, 20 seconds. The rocket is maneuvering itself to the proper orientation for deploying the satellite.
9:53 p.m. local (12:53 a.m. EDT)
T+plus 12 minutes, 50 seconds. Thrust has tailed off from the solid-fueled fourth stage to complete the burn.
9:53 p.m. local (12:53 a.m. EDT)
T+plus 12 minutes, 5 seconds. All systems appear normal as fourth stage continues to burn.
9:52 p.m. local (12:52 a.m. EDT)
T+plus 11 minutes, 46 seconds. Fourth stage stage ignition! The commercial Orion 38 solid rocket motor has been lit to complete the job of delivering the payload into orbit.
9:52 p.m. local (12:52 a.m. EDT)
T+plus 11 minutes, 32 seconds. Confirmation now received that the third stage was jettisoned from the fourth stage. This sheds the Peacekeeper portion of Minotaur and the commercial solid-fuel motor takes over.
9:52 p.m. local (12:52 a.m. EDT)
T+plus 11 minutes, 24 seconds. The fourth stage battery has been activated.
9:51 p.m. local (12:51 a.m. EDT)
T+plus 10 minutes, 45 seconds. Minotaur is 515 km in altitude, some 3,300 km downrange.
9:49 p.m. local (12:49 a.m. EDT)
T+plus 8 minutes, 30 seconds. Minotaur is 450 km in altitude, some 2,500 km downrange.
9:49 p.m. local (12:49 a.m. EDT)
T+plus 8 minutes. Minotaur remains in the ballistic coast phase of flight. The spent third stage will be shed in about three-and-a-half minutes from now, followed by fourth stage ignition.
9:48 p.m. local (12:48 a.m. EDT)
T+plus 7 minutes, 40 seconds. Systems aboard the Minotaur continue to look good.
9:48 p.m. local (12:48 a.m. EDT)
T+plus 7 minutes, 5 seconds. Minotaur is 390 km in altitude, some 1,900 km downrange, traveling at 6.9 km per second.
9:46 p.m. local (12:46 a.m. EDT)
T+plus 5 minutes. Performance so far in this launch indicates the target apogee altitude high point will be reached at 540 km for the fourth stage orbit circularization burn.
9:45 p.m. local (12:45 a.m. EDT)
T+plus 4 minutes, 40 seconds. Minotaur is 260 km in altitude, some 1,000 km downrange.
9:44 p.m. local (12:44 a.m. EDT)
T+plus 3 minutes, 31 seconds. The solid-fuel third stage has burned out, and the rocket is beginning a brief coast period lasting a little more than eight minutes.
9:44 p.m. local (12:44 a.m. EDT)
T+plus 3 minutes, 10 seconds. Good pressure in the third stage.
9:43 p.m. local (12:43 a.m. EDT)
T+plus 2 minutes, 44 seconds. The rocket's 92-inch payload fairing nose cone has jettisoned, exposing SBSS to space.
9:43 p.m. local (12:43 a.m. EDT)
T+plus 2 minutes, 18 seconds. The spent second stage just separated and the Peacekeeper SR120 third stage is firing now.
9:43 p.m. local (12:43 a.m. EDT)
T+plus 2 minutes, 2 seconds. Everything remains nominal aboard Minotaur. The rocket's second stage has burned out, standing by for jettison.
9:42 p.m. local (12:42 a.m. EDT)
T+plus 90 seconds. Second stage motor pressure is nominal.
9:42 p.m. local (12:42 a.m. EDT)
T+plus 70 seconds. Rocket is flying normally as the second stage fires.
9:42 p.m. local (12:42 a.m. EDT)
T+plus 62 seconds. The first stage has exhausted its supply of solid fuel and separated. The second stage's Peacekeeper SR119 motor has ignited to continue the flight toward space.
9:41 p.m. local (12:41 a.m. EDT)
T+plus 40 seconds. The rocket is passing through the region of maximum aerodynamic pressures of ascent.
9:41 p.m. local (12:41 a.m. EDT)
T+plus 30 seconds. The space booster is accelerating into the nighttime sky from Vandenberg Air Force Base with the power provided by the Peacekeeper SR118 solid rocket motor.
9:41 p.m. local (12:41 a.m. EDT)
LIFTOFF! Liftoff of the Minotaur 4 rocket launching a surveillance satellite to reconnoiter the threats and dangers in space.
9:40 p.m. local (12:40 a.m. EDT)
T-minus 30 seconds. Data recording charts are running.
9:40 p.m. local (12:40 a.m. EDT)
T-minus 1 minute.
9:39 p.m. local (12:39 a.m. EDT)
T-minus 90 seconds. The rocket ordnance has been armed.
9:39 p.m. local (12:39 a.m. EDT)
T-minus 2 minutes. Auto sequence start. Minotaur's flight computer is controlling the countdown.
9:38 p.m. local (12:38 a.m. EDT)
T-minus 2 minutes, 30 seconds. Coming up on auto sequence start in 30 seconds.
9:38 p.m. local (12:38 a.m. EDT)
T-minus 3 minutes. The Air Force-controlled Western Range is clear for launch.
9:37 p.m. local (12:37 a.m. EDT)
T-minus 3 minutes, 30 seconds. The C-band tracking beacon is functioning as expected on internal power.
9:36 p.m. local (12:36 a.m. EDT)
T-minus 4 minutes, 15 seconds. The flight computer is armed.
9:36 p.m. local (12:36 a.m. EDT)
T-minus 5 minutes. The rocket's avionics are switching to internal power.
9:35 p.m. local (12:35 a.m. EDT)
T-minus 5 minutes, 30 seconds. The SBSS spacecraft is confirmed to be running on internal battery power for launch.
9:35 p.m. local (12:35 a.m. EDT)
T-minus 6 minutes. The final management poll concurs that all systems remain "go" for launch right on time tonight.
9:33 p.m. local (12:33 a.m. EDT)
T-minus 7 minutes, 45 seconds. And now the safety system is armed.
9:31 p.m. local (12:31 a.m. EDT)
T-minus 9 minutes, 30 seconds. The rocket's safety system has switched to internal power.
9:29 p.m. local (12:29 a.m. EDT)
T-minus 12 minutes. The exact 0441:00 GMT (9:41:00 p.m. local) launch time is being loaded into the rocket's flight computer.
9:27 p.m. local (12:27 a.m. EDT)
Safety officials confirm that the hazard area is clear for launch.
9:25 p.m. local (12:25 a.m. EDT)
The final launch readiness poll of various team members was just conducted. All systems are "go" for liftoff of the Minotaur rocket and the SBSS spacecraft from Vandenberg Air Force Base, Calif.
9:24 p.m. local (12:24 a.m. EDT)
Launch team members will be polled in the next few minutes to confirm everything is ready for liftoff.
9:23 p.m. local (12:23 a.m. EDT)
T-minus 18 minutes. Ground and high-altitude winds are acceptable for launch.
9:22 p.m. local (12:22 a.m. EDT)
Minotaur's target launch time is 0441:00 GMT (9:41:00 p.m. local).
9:21 p.m. local (12:21 a.m. EDT)
The countdown is passing the T-minus 20 minute mark. Not only will the SBSS satellite help protect the military's critical communications, navigation and reconnaissance spacecraft, the clearer view of orbital objects will increase protection for commercial craft as well.

"I think it's clear that our country is very dependent on space, both economically and militarily," said Todd Citron, Boeing's director of advanced space and intelligence systems.

"To protect those assets in space requires understanding what's going on in space, which is the whole job of space situational awareness. SBSS is really going to revolutionize space situational awareness with the improvement and sensitivity and capacity.

"To the person on the street this is a critical element of ensuring that things essential to our economy and our health as a nation continue."

9:16 p.m. local (12:16 a.m. EDT)
T-minus 25 minutes. The SBSS satellite is the prominent feature in the U.S. military's efforts to gain a better understanding of the risks that orbital debris and enemy craft pose to national assets.

"Space situational awareness is an essential component to maintaining space superiority. The benefits that SBSS brings is that by operating solely in space the SBSS satellite will circumvent the current terrestrial restrictions and limitations of weather, Earth line-of-sight and nighttime-only operations. This capability that SBSS will deliver will triple the probability of event detection, double the sensitivity and increase capacity by 10 times," said Lt. Col. Robert Erickson, SBSS Space Situational Awareness Squadron commander.

9:12 p.m. local (12:12 a.m. EDT)
T-minus 29 minutes. A test of the rocket's safety system is getting underway.
9:06 p.m. local (12:06 a.m. EDT)
Now 35 minutes left in the countdown to launch of the Space Based Space Surveillance satellite aboard the first orbital mission for the Minotaur 4 rocket.

"This satellite is going to revolutionize the way we track objects in space by not being constrained by weather, the atmosphere or the time of day. This capability will be essential to our space situational awareness architecture for the near future and beyond. SBSS will help make our space assets safer and more secure, keeping America at the forefront of space," says Col. J.R. Jordan, SBSS mission director.

"The space vehicle and the ground segment are not the only success stories here. Orbital has effectively integrated three solid rocket motors from decommissioned Peacekeeper ICBMs into a Minotaur 4 launch vehicle to usher in a new era of a lower cost, responsive, space asset. The success of the Minotaur 4 rocket is going to change our launch business."

9:05 p.m. local (12:05 a.m. EDT)
The rocket's tracking beacon is being checked out.
8:59 p.m. local (11:59 p.m. EDT)
T-minus 42 minutes and counting. The countdown clocks are scheduled to roll uninterrupted all the way to liftoff at 9:41 p.m. No holds are planned in the Minotaur's final countdown.
8:57 p.m. local (11:57 p.m. EDT)
The rocket's avionics were powered to permit the inertial guidance system final pre-launch alignment a short time ago. And that task has been completed successfully.
8:54 p.m. local (11:54 p.m. EDT)
No technical problems are being worked in the countdown, activities are on schedule and the weather is looking good.
8:51 p.m. local (11:51 p.m. EDT)
And we're now back with tonight's launch of the Minotaur 4 rocket to begin a new era of surveying objects and debris orbiting the planet. The communications problems have been resolved.

Countdown clocks are progressing toward a liftoff during the 9:41 to 9:55 p.m. launch opportunity for the Space Base Space Surveillance satellite from Vandenberg Air Force Base in California.

6:15 p.m. local (9:15 p.m. EDT)
We regretfully announce that an Air Force communications snafu is blocking reporters' ability to follow the launch countdown. That means Spaceflight Now cannot provide our comprehensive live coverage of this launch that readers have relied upon for years.

In fact, never before in our 11 years of reporting on Vandenberg Air Force Base space launches has this obstacle been encountered.

It is unfortunate that the problem is preventing the news media from adequately telling the story of this $858 million mission involving a critical military satellite launch.

Until the problem is corrected, we won't be posting any further updates on the SBSS mission.

4:45 p.m. local (7:45 p.m. EDT)
Launch of the Minotaur rocket is supposed to occur five hours from now. However, we've not heard any status on pre-flight preparations today or whether the countdown has started.

We will begin our live launch coverage when, or if, information starts flowing tonight.

The Minotaur 4 rocket and an innovative space surveillance satellite have a Saturday night launch date scheduled at Vandenberg Air Force Base, California.

Liftoff time is 9:41 p.m. local (12:41 a.m. EDT) from Space Launch Complex 8 on the southside of the base.

The evening's launch opportunity extends 14 minutes to 9:55 p.m. to ensure the mission reaches the desired orbit.

"We're ready to go and we understand the weather is improving here. It should be a nice opportunity for the local community to see the rocket on Saturday evening," said Col. J.R. Jordan, mission director from the Air Force's Space Superiority Systems Wing at the Space and Missile Systems Center.

The launch time outlook calls for clear skies, good visibility, northerly winds of 8 to 12 knots, a temperature in the mid-60s F and no concerns for violating any of the weather rules.

"High pressure moves into the Vandenberg area and will bring warm, summer weather today through Sunday," the forecast issued Thursday says. "As the high pressure pushes in from the south, our normal cooling sea breeze will switch to a warm, offshore flow increasing temperatures and pushing the marine layer offshore."

Orbital Sciences Corp. oversees the Minotaur rocket program for the Air Force, having conducted 17 launches successfully to date. The new Minotaur 4 booster, which is making its inaugural flight as a satellite-launcher Saturday, uses leftover Peacekeeper missile motors for the lower three stages and a commercial fourth stage to inject payloads weighing as much as two tons into Earth orbit.

Readers may remember previous space launches using the Minotaur 1 rocket, which utilizes Minuteman missile stages to loft half-ton cargos. Other versions of Minotaurs that have flown were suborbital vehicles.

Saturday's payload is the long-awaited Space Base Space Surveillance satellite, or SBSS for short, that promises dramatic improvements in the military's ability to identify and track objects in orbit.

From its 392-mile operational altitude circling the entire planet from pole-to-pole, SBSS will use its optical telescope to provide analysts the data they need to keep better tabs on space debris and guard against accidental collisions.

What's more, the reconnaissance provided by the $858 million mission will watch vital military satellites for potential danger posed by enemies.

"Every day, threats to our nation's valuable satellites and space platforms are growing," Jordan said. "SBSS will revolutionize our ability to find and monitor objects that could harm the space assets we depend on for security, communications, weather forecasting and many other essential services."

Enhancing situational awareness in space has become a major objective for the military. Putting a satellite into orbit to scan the sky will narrow gaps in ground-based space tracking that is limited by geographic locations, nighttime viewing and the weather.

"The probability that you can detect events in space is improved by a factor of three by launching SBSS. Also, the time to detect that somebody has made a change up in space is improved by a factor of three," said Todd Citron, Boeing's director of advanced space and intelligence systems.

"So it's fairly substantial improvements in performance, and that stems from SBSS brings better timeliness, better sensitivity, as well as increased capacity to be able to understand what's going on in space."

After lifting off from Vandenberg, the Minotaur's flight path will head southward over the Pacific Ocean. The Peacekeeper stages perform their sequential firings within three-and-a-half minutes, each dropping away as the next one lights.

Once that third stage burns out 120 miles in altitude, the rocket begins a brief a ballistic coast and soars away from the planet to reach a point 330 miles high. That's when the fourth stage ignites to provide the boost needed to circularize the orbit at 336 miles.

SBSS separates from the rocket 14 minutes and 41 seconds after liftoff to start its seven-year life.

Later maneuvers during the early on-orbit testing and commissioning activities will raise the orbit by more than 50 miles to the intended operational perch.

Boeing leads the SBSS project and Ball Aerospace built the satellite.

"We've thoroughly rehearsed all plans and procedures, the Satellite Operations Center has been configured for flight operations, and the SBSS satellite and Minotaur launch vehicle are completing final preparations. We're looking forward to putting this spacecraft into orbit so that it can perform its vital mission," Citron said.

"I can safely say that our entire program is looking forward to Saturday's launch and the start of this critical mission protecting our country's space assets," said Harold Montoya, Ball's director of programs and operations for defense systems.

And a reminder that if you will be away from your computer but would like to receive occasional countdown updates, sign up for our Twitter feed to get text message updates on your cellphone. U.S. readers can also sign up from their phone by texting "follow spaceflightnow" to 40404. (Standard text messaging charges apply.)