Lockheed Martin's venerable family of Atlas rockets are in the midst of a back-to-back lineup of interplanetary launches, the first deep space missions for Atlas boosters in over 27 years.

Atlas 5 launches with NASA's newest Mars probe last week. Photo: Patrick H. Corkery & Adam Mattivi/Lockheed Martin See larger image version here

Friday morning's successful launch of the Mars Reconnaissance Orbiter aboard an Atlas 5 rocket marked the first planetary science mission carried aboard an Atlas vehicle since Pioneer 13 flew to Venus three decades ago.

Pioneer 13 was launched August 8, 1978, aboard a heritage model of Atlas-Centaur rockets from Cape Canaveral's Complex 36A, located just a few miles south of the cutting edge Complex 41 that was the starting point for the Atlas 5's spectacular blastoff Friday morning.

Pioneer released several instrumented probes that entered the thick, hot and sultry Venetian atmosphere to conduct observations of various elements of the planet. Data returned to Earth included information about the uppermost reaches of Venus' atmosphere, temperature and pressure in lower regions, and cloud composition.

This time, the $720 million Atlas payload is heading outward in the solar system, where it will enter orbit around Mars on March 10 of next year to begin over four years of comprehensive mapping, subsurface exploration, and communications relay duties for current and future landers.

"(Atlas) sent us on a course that was almost picture-perfect, and we could not have asked for a better launch," said MRO project manager Jim Graf.


Additional coverage for subscribers:
VIDEO: LAUNCH OF MARS ORBITER SHORT | LONGER VERSION
VIDEO: LIFTOFF AS SEEN FROM SHUTTLE VAB ROOF PLAY
VIDEO: PLAYALINDA BEACH TRACKING CAMERA PLAY
VIDEO: TRACKING CAMERA POSITIONED SOUTH OF PAD PLAY
VIDEO: STATIC TEST ROAD VIEWING MOUND PLAY
VIDEO: LAUNCH COMPLEX'S EAST CAMERA PLAY
VIDEO: LAUNCH COMPLEX'S SOUTH CAMERA PLAY
VIDEO: VERTICAL INTEGRATION FACILITY ROOF-CAM PLAY
VIDEO: POST-FLIGHT INTERVIEW NASA LAUNCH DIRECTOR PLAY
VIDEO: POST-LAUNCH NEWS CONFERENCE DIAL-UP | BROADBAND

VIDEO: THURSDAY'S LAUNCH ATTEMPT IS SCRUBBED PLAY
VIDEO: ROCKET IS ROLLED TO PAD WEDNESDAY NIGHT PLAY
VIDEO: ATLAS 5 ROCKET PRE-LAUNCH PREPS PLAY
VIDEO: MARS RECONNAISSANCE ORBITER PRE-LAUNCH PREPS PLAY
VIDEO: NARRATED ATLAS 5 LAUNCH ANIMATION PLAY
VIDEO: SCIENCE PREVIEW BRIEFING DIAL-UP | BROADBAND 1 & 2
VIDEO: PRE-LAUNCH NEWS CONFERENCE DIAL-UP | BROADBAND 1 & 2
SUBSCRIBE NOW


The Atlas launch team can now focus on the next mission on their manifest -- the early morning launch next January 11 of the New Horizons probe to embark on a decade-long journey to fly past Pluto and its moon Charon. New Horizons will then target up to several Kuiper Belt objects orbiting the Sun past the Pluto system. The mission will be first visit to such bodies in the outer solar system.

While Friday's Mars launch used the "401" configuration of the Atlas 5, with a four-meter payload fairing atop the nose, no solid rocket boosters, and a Centaur upper stage with a single RL10 powerplant, the next flight will give an extra kick to its cargo.

New Horizons will be launched aboard an Atlas 5 "551" vehicle, with a bulbous five-meter payload shroud built by the Swiss contractor Contraves, five Aerojet-built solid rocket boosters, another single-engine Centaur, and a Star 48B third stage. The rocket will send the probe on a speedy trajectory past the Moon within nine hours and on to a Jupiter flyby in late February 2007. Pluto arrival will be in about 2015.

The 1,025-pound spacecraft is currently sitting in a vacuum chamber at NASA's Goddard Space Flight Center in Maryland, where it is undergoing tests before being shipped to Kennedy Space Center to begin launch preparations.

Before arriving at Goddard, New Horizons underwent vibration testing at the Johns Hopkins Applied Physics Laboratory, which designed and built the spacecraft. Spin tests have also been conducted, and acoustic tests should be performed before the probe leaves the Goddard facility.

Engineers discovered a hardware problem with one of the craft's two solid state recorders used to store science data before being transmitted back to Earth via its 83-inch dish-shaped high gain antenna. Teams traced the problem to a manufacturing defect in a circuit card, and the device will be removed and repaired in September when New Horizons completes testing before being transported to the Cape.

"Although one would like a spacecraft that is completely free of problems from the minute it is put together, I'm very glad we found the SSR (solid state recorder) problem, since it could not be fixed after launch," wrote principal investigator Alan Stern in an online update earlier this month.

An artist's concept of the New Horizons spacecraft at Pluto. Credit: Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute (JHUAPL/SwRI)

The Centaur upper stage for the mission will arrive at the Cape around August 29, followed on September 1 by the Atlas first stage to begin inspections and processing in a high bay at the Atlas Spaceflight Operations Center. The first stage will then be moved to Complex 41's Vertical Integration Facility to be erected atop its mobile launch table. There it will receive its Centaur, five solid rocket boosters and payload.

A wildcard in the planned launch of New Horizons surrounds the radioisotope thermoelectric generator used to power the probe in the deepest extent of the solar system where the Sun is 1,000 times fainter than here on Earth. The RTG contains ceramic pellets of plutonium dioxide to be naturally decayed, while the heat produced from the radioactivity will be converted to energy.

Provided by the U.S. Department of Energy, such RTG's have been included on many past deep space probes such as the Cassini mission to Saturn, the Galileo orbiter of Jupiter, and the Voyager craft now on their way out of the solar system.

However, law requires a exhaustive review process for nuclear space missions by the Department of Energy and an interagency panel to report to NASA, which then must submit a request for permission to launch to the White House. Though no issues are expected, the President or his science adviser must give the official clear to launch this fall.

An environmental impact summary was released last month outlining the risks associated with the potential for a launch accident that could release radioactive material. The mean probability of a plutonium release during the flight is about 1 in 300.

"The maximum dose received by an individual within the potentially exposed population would be...about 80 percent of the normal background radiation received by each member of the U.S. population annually," the report said.

Overall, the chance of a launch accident through the entire mission is 6.2 percent, with a 85 percent probability such an event would not release radioactive plutonium. An accident later in the launch sequence would present less likelihood for such a release.

It is expected NASA will continue to contract future deep space missions to launch on the two new-generation rockets now operational at Cape Canaveral. In addition to the Atlas 5, Boeing's Delta 4 rocket family is also on the table. These vehicles offer more performance and capacity than earlier Atlas and Delta boosters for extra weight and science instruments to be sent skyward.

NASA's next rover to visit the Martian surface -- called Mars Science Laboratory and scheduled to launch by the end of the decade -- will likely require a lift capability that Atlas 5 or Delta 4 can provide. Other concepts such as a Europa orbiter, the Juno mission to Jupiter, and various next-generation environmental satellites could also use such rockets.