Launch Plus Five Years: A Ways Traveled, A Ways To Go

It's been five years since New Horizons roared into the Florida skies - speeding from Earth faster than any spacecraft before it - and began its journey to the unexplored regions of the planetary frontier. Today, with New Horizons more than halfway through its voyage to Pluto, mission team members look back on the historic launch and a few of the events since.

"Five years in flight already! It's a credit to our spacecraft and operations teams that we've traveled so far without any big problems cropping up," says New Horizons Principal Investigator Alan Stern, of the Southwest Research Institute.

"We still have four years to go until encounter operations begin, but we're already excited to see the light at the end of the tunnel that comes in 2015. Go New Horizons!"

First Attempts
At noon EST on Jan. 17, 2006, New Horizons sat atop an Atlas V rocket at Launch Complex 41, Cape Canaveral Air Force Station, Florida. Just above it, though, were layers of clouds that blocked the rocket's path to the skies.

"We continued to hope that the clouds would break long enough to allow us a chance to launch, but no luck," says Mission Operations Manager Alice Bowman, who was monitoring the spacecraft with her team in the mission operations center at the Johns Hopkins University Applied Physics Laboratory. The call to scrub the launch came at the end of a two-hour window.

Jan. 18: new day, same tough luck. Thanks to a power outage at APL in Maryland, the mission operations center was running on backup generators and large cooling hoses were routed through rooms to keep computers (and operators) running at safe levels. A consequence of this otherwise effective workaround was that spacecraft engineers supporting the launch would have to share just a few workstations; they would also have to share telemetry displays, which limited the amount of information available at any one time.

"We were concerned that the limited availability of telemetry could interfere with any contingency response we would have to make in case of an anomaly after we separated from the launch vehicle," recalls APL's Dave Kusnierkiewicz, then the New Horizons mission systems engineer, who was manning a console near the launch site at Kennedy Space Center. "So, we decided to wait another day."

The Charm
Third try, Jan. 19: power had returned to APL, yet clouds returned to the Cape. This day, though, the weather cooperated just in time. "The clouds cleared just enough for our launch at 2 p.m., the very end of our launch window," Bowman says.

"While we [in the MOC] were proud of the successful launch, we all knew that the we didn't have a viable mission until we received that first bit of telemetry from the spacecraft [after it separated from the launch vehicle] and could evaluate how it had faired during the launch."

That data reached mission ops exactly 52 minutes and 40 seconds after liftoff, through NASA's Deep Space Network antenna station in Canberra, Australia. "All telemetry showed nominal status," Bowman says. "We now had a mission!"

The team's focus turned to transmitting commands, downloading and analyzing data the spacecraft had recorded since launch, priming the propulsion system, reducing the spacecraft's stabilizing spin (from 62 to 15 rotations per minute), and making sure New Horizons' autonomy (self-checking) system was configured for post-launch operations.

"Eleven hours and 20 minutes after launch, the spacecraft mission operations and engineering team accomplished all the objectives, and we called it a day," Bowman says.

"At first, Jan. 19 seemed like it was going to be a repeat of Jan. 17," says Kusnierkiewicz, now the chief engineer in APL's Space Department.

"Lots of recycling of the countdown procedure, which involves a hierarchy of polling to ensure launch readiness. When we finally got our chance, everything and everyone performed flawlessly. It was actually much easier than not launching. And a lot more fun."

So Far, a Smooth Flight
"January 19, 2006, was the culmination of the work of a marvelous team who had designed, built and launched the spacecraft," says New Horizons Project Manager Glen Fountain, of APL.

"On that day it was turned over to another marvelous team that has brought the spacecraft over halfway in both time and distance to our goal."

APL mission design lead Yanping Guo reports that New Horizons has had a very smooth and accurate flight through the outer solar system, needing fewer trajectory correction maneuvers than planned before launch. New Horizons' odometer (if it had one) would read 3.12 billion kilometers (1.94 billion miles) or 20.87 astronomical units - nearly 21 times the distance between the Sun and Earth.

New Horizons is now 18.92 astronomical units from the Sun, moving 15.83 kilometers per second toward Pluto for an encounter on July 14, 2015. In 2010 the spacecraft zipped through a number of "halfway" milestones: half the distance from Earth (launch location) to Pluto (at flyby time); halfway to Pluto's distance at the encounter; half the sun-centered mileage traveled between Earth and Pluto; halfway in travel time to reach Pluto.

"Passing all of our halfway points this past year was certainly encouraging and our upcoming crossing of the orbit of Uranus on March 18 - the same day the MESSENGER spacecraft goes into orbit around Mercury - will be another milestone of progress made," says Becca Sepan, the real-time mission operations lead at APL.

With so much time between launch and the Pluto encounter, Sepan says she's often asked how the team stays busy.

"I think even we have been surprised just how much there is to do during the cruise to Pluto. The first year and a half was spent commissioning the spacecraft and executing a very successful Jupiter flyby campaign [in early 2007] that included extensive science observations. We thought things might slow down a bit after that but in fact, we've been busy since then with activity-packed annual checkouts, ground system upgrades, responding to the occasional spacecraft anomaly, getting accustomed to dealing with long round-trip light [radio transmission] times, and most importantly, preparing for the Pluto encounter.

"The encounter is a once-in-a-lifetime opportunity so we're taking great care and lots of time and effort to plan every second with purpose," she continues. "To think, in another five years, we'll be looking at the images and other data that will show the results of all our work!"

Time for Science
The early 2007 flight through the Jupiter system resulted in the mission's largest science haul to date. Photos of Jupiter, its largest (and smallest) moons and even its faint rings captured the attention of causal sky watchers and professional astronomers alike.

Science team Co-Investigator Fran Bagenal remembers how she and fellow Co-Is Dave McComas and Ralph McNutt (principal investigators for SWAP and PEPSSI, respectively) and team members Heather Elliott, Matt Hill and Dennis Haggerty gathered in a University of Colorado Laboratory for Atmospheric and Space Physics (LASP) conference room in May 2007 for mini-workshop on data New Horizons collected in Jupiter's magnetotail. They were looking at three months' worth of data, gathered as New Horizons cruised millions of miles "downtail" from the giant planet.

The data sets that the small team assembled and stuck on the wall that day went all the way around the room. Bagenal says that meeting only kicked off the discoveries and the discussions.

"So far there are at least six papers on the magnetotail, a Ph.D., an M.S. and more degrees coming," she says. "Moreover, the New Horizons observations provoked a new way of looking at solar wind interaction with the Jovian magnetosphere. I expect further papers and much debate."