Less than three days since it launched its Antares booster from Pad 0A at the Mid-Atlantic Regional Spaceport (MARS) on Wallops Island, Va., Orbital Sciences Corp. has successfully brought the second Cygnus cargo ship to a smooth berthing at the International Space Station (ISS). Flying high above Africa—and with the pale Moon coming into view of the station’s external cameras during the final moments—Cygnus was grappled by the 57.7-foot (17.6-meter) Canadarm2 robotic arm at 6:08 a.m. EST (11:08 a.m. GMT) Sunday. At the controls of the arm was NASA astronaut Mike Hopkins, assisted by fellow U.S. Orbital Segment (USOS) crewmen Koichi Wakata and Rick Mastracchio. Less than two hours later, Cygnus was firmly berthed at the “nadir” (or Earth-facing) port of the Harmony node, preparatory to hatch opening and crew ingress Sunday afternoon.
“The arrival capped the first successful contracted cargo delivery by Orbital Sciences,” explained NASA in a Sunday news release. The Dulles, Va.-based aerospace company received a $1.9 billion Commercial Resupply Services (CRS) contract from NASA in December 2008, whose language called for eight Cygnus missions by 2016 to haul a total of 44,000 pounds (20,000 kg) of supplies, payloads, and equipment to the ISS. As part of the requirements for the CRS missions, both Orbital and SpaceX were required to first execute a satisfactory Commercial Orbital Transportation Services (COTS) demonstration flight. SpaceX completed the COTS mission of its Dragon cargo ship in May 2012, followed by Orbital’s ORB-D test flight in September-October 2013. With the enormous success of both missions, Orbital and SpaceX were cleared to begin their dedicated CRS commitments. SpaceX has already flown two of its 12 contracted CRS flights—the first in October 2012 and most recently in March 2013—while the current ORB-1 flight represents the first CRS mission by Orbital. As a result, the United States now has two fully fledged private contractors restocking the space station.
Following Thursday’s picture-perfect liftoff of Antares, the ORB-1 vehicle—named “Spaceship C. Gordon Fullerton,” in honor of the former shuttle astronaut and research pilot who died last August—underwent more than two days of orbit-raising and “phasing” maneuvers to bring it into the neighborhood of the ISS. Late Saturday, at a distance of about 125 miles (200 km), closing at a rate of about 15 mph (24 km/h), Orbital tweeted that its baby swan “continues to perform well with less than 12 hours to grapple and berthing,” whilst NASA astronaut Cady Coleman quipped that “#Cygnus is on a collision course with @NASA #ISS! No worries though…It’s on purpose!”
Early Sunday morning, Hopkins, Wakata, and Mastracchio set to work configuring Robotic Work Station (RWS) assets in the Cupola and Destiny laboratory module, and at 4 a.m. EST it was confirmed that the ISS crew had successfully commanded Cygnus’ strobe lights “on.” An hour later, the cylindrical cargo ship had drawn to 820 feet (250 meters) and held its position, as planned, until it was cleared to continue its approach toward the space station. At 660 feet (200 meters), Cygnus entered the so-called “Keep Out Sphere”—a virtual exclusion zone, extending around the ISS to prevent a collision—and by 5:45 a.m. EST had reached its next “hold” point at 100 feet (30 meters). Shortly afterward, following “Go/No-Go” polls at Orbital’s Mission Operations Center in Dulles, Va., and at NASA’s Mission Control Center in Houston, Texas, ISS Flight Director Brian Smith gave authority for Cygnus to maneuver to 35 feet (10 meters), within range of Canadarm2. Creeping toward its quarry at a rate of just 0.6 feet per second (0.2 meters per second), at 6 a.m. Mike Hopkins was given the “Go” for capture by Capcom David Saint-Jacques. As the station flew high above Africa, Canadarm2 grasped Cygnus at 6:08 a.m. in a tight mechanized embrace.
In accomplishing this feat, Hopkins becomes the first U.S. astronaut to be present for two Cygnus berthings. He arrived at the ISS aboard Soyuz TMA-10M late on 25 September 2013, just a few days before the rendezvous and berthing of the ORB-D cargo ship. With the successful grappling of ORB-1, the actual physical berthing of the craft at the nadir port of the Harmony node was expected to occur about two hours later, but was completed at 8:05 a.m. EST. The two-part protocol saw hooks from Harmony’s nadir Common Berthing Mechanism (CBM) extend and grab Cygnus to pull their respective CBMs into contact, after which a series of 16 bolts were driven to rigidize the two vehicles. This task was completed about 20 minutes later, and Koichi Wakata set to work performing early leak checks. By early afternoon the fast-working astronauts were ready to open Cygnus’ hatch, and at 12:10 p.m. EST they were given a “Go” to begin pressure equalization, ahead of hatch opening and ingress into the ship’s Pressurized Cargo Module (PCM). Shortly after ingress, Orbital Sciences tweeted: “#Cygnus cargo hatch opened at @ISS. Everything looks good inside.”
Cygnus will remain berthed at the ISS until “mid-February,” with its 2,780 pounds (1,260 kg) of payloads and supplies expected to be unloaded in the coming days. “The cargo is comprised of vital science experiments, crew provisions, spare parts and other hardware,” explained NASA in a post-berthing news update. “This includes 23 student-designed science experiments. One newly arrived investigation will study the decreased effectiveness of antibiotics during spaceflight. Another will examine how different fuel samples burn in microgravity, which could inform future design for spacecraft materials.” AmericaSpace will continue to cover these events, with a major article by Leonidas Papadopoulos scheduled to appear next week to detail one of the mission’s educational payloads.
In the aftermath of today’s successful ORB-1 berthing, the congratulatory tweets flooded in. Former astronaut Ron Garan extended warm good wishes to the Orbital Sciences and NASA teams, as well as to Hopkins, Wakata, and Mastracchio, for their sterling work. But perhaps the most poignant reflection of how far the ISS program has traveled in recent years came in a tweet from the Canadian Space Agency (CSA), which noted: “Japanese man uses Canadian robot to capture American ship. Everybody wins.” Although, strictly speaking, it was U.S. astronaut Hopkins at the Canadarm2 controls, the sentiment was effective. And, as amply illustrated by the stunning views of Cygnus in the grasp of the arm, hanging in the ethereal blackness of space, with an ever-changing Earth hanging as a backdrop, that sentiment was that “The Future” is not some abstract thing, out of reach.
The Future is now.