OrbitalHub

Credits: ESA – D. Ducros, 2009

While the media has been busy with the launch of the STS-125 Atlantis for the Hubble Servicing Mission #4 from Cape Canaveral, another exciting launch is undergoing preparations further south, in Kourou, French Guiana.

Herschel and Planck are scheduled to launch on May 14, 2009. They will be stacked on the same Ariane 5 launch vehicle.

The two spacecraft will separate shortly after the launch (Herschel a couple of minutes before Planck) and will proceed independently to the L2 point of the Sun-Earth system. L2 is a point in space that has some special characteristics situated at 1.5 million kilometers from Earth in the opposite direction to the Sun. Herschel and Planck will operate from independent orbits around the L2 point.

Credits: ESA – D. Ducros, 2009

Stacked together, Herschel and Planck measure around 11 m in length, 4.5 m in diameter, and have a mass of approximately 5,700 kg. The piece that holds them together is called Sylda. Sylda is a support structure for Herschel and forms a protective cover for Planck.

The final orbit for Herschel will be a large, 900×500-thousand km, Lissajous orbit around the L2. There are three trajectory-correction maneuvers (TCM) planned for Herschel, during days L+1, L+2, and L+12. Planck will require a total of 5 TCMs that will enable it to operate from a 300×200-thousand km Lissajous orbit also around the L2 point.

The Lissajou orbits are inherently unstable, so both spacecraft will need regular thruster burns throughout their missions to stay on track.

“Without regular trajectory corrections, they would naturally drift off into a useless orbit about the Sun or Earth, with the rate of drift increasing with time,” says Gottlob Gienger, the senior flight dynamics advisor for the Herschel and Planck missions.

To read more about the launch of Herschel and Planck, you can visit the dedicated page on ESA’s website.

Credits: Arianespace

An updated version of the Soyuz launch vehicle will liftoff at the end of the year from the European Spaceport at Kourou in French Guyana.

Soyuz will complete the range of launchers operated by Arianespace, which already includes the Ariane 5, with the Vega small launcher soon to come.

The construction of the Soyuz site in Guyana has reached a major milestone: the construction of the launch system has begun. The launch system supports and services the launch vehicle when it is erected for liftoff.

The concrete launch pad supports a multi-segment steel ring inset (known as the support crown). Two umbilical masts have also been positioned on top of the support crown. The masts, together with four support booms, will keep the launch vehicle in position on the launch pad. The two towers visible at the launch site will protect the Soyuz vehicle from lightning strikes.

Credits: Arianespace

One interesting detail about the launch site is that the support crown is fixed on the launch pad, in contrast to the launch pads built for Soyuz in Russia and Kazakhstan, as the updated Soyuz operated from Kourou is able to manage the launch azimuth during ascent.

You can read more about the Kourou Spaceport on the Arianespace website.

Credits: ESA/CNES/ARIANESPACE-Service Optique CSG 2002

Arianespace accounted for 50 percent of all commercial launches to geostationary transfer orbit during 2008 and retained its strong market share, which represented 72 percent of the orders booked in 2008.

Arianespace was founded in 1980. Among its 23 shareholders are the French space agency CNES with thirty-four percent and EADS Astrium with thirty percent. With only around 300 employees, the company has generated sales of about one billion euros in 2008.

2009 will be the year of the launcher family for Arianespace, as Arianespace Chairman and CEO Jean-Yves Le Gall pointed out during the company’s New Year’s press conference in Paris. The development of the Vega launcher is being finalized, the maiden launch of the medium-lift Soyuz launcher from Kourou in French Guiana will take place this year, and more than six missions are scheduled for Ariane 5.

“As a result of our launcher family strategy, Arianespace has a sustained agility that allows us to be ever more responsive to our customers,” Le Gall told the journalists. “The agility has been demonstrated with our 28 consecutive mission successes for Ariane 5 and the 21 for Soyuz – and is underscored by launches that are on target, and on time.”

With a full range of payload lift capabilities, including Vega, Soyuz, and Ariane 5, Arianespace is able to meet the changing trends in satellite weights, orbiting everything from light weight scientific payloads to heavy telecommunication relay platforms.

Credits: NASA

Orbital will employ its Taurus II medium-lift launch vehicle and the Cygnus spacecraft in order to service the International Space Station (ISS) under the Commercial Resupply Services (CRS) contract.

Orbital is one of the two companies awarded CRS contracts under the Commercial Orbital Transportation Services Project (COTS).

NASA announced the COTS project on January 18, 2006. The purpose of the program is to stimulate the development of access to low Earth orbit (LEO) in the private sector. At the time, with the imminent retirement of the Space Shuttle fleet, NASA was faced with the option of buying orbital transportation services on foreign launch systems: the Russian Soyuz / Progress, the European Ariane 5 / ATV, or the Japanese H-II / HTV.

Another factor taken into consideration by NASA was that competition in the free market could lead to the development of more efficient and affordable launch systems compared to launch systems that a government agency could build and operate.

Credits: Orbital

Orbital relies on proven experience in launch vehicle technology. Taurus II is designed to provide low-cost and reliable access to space, and it uses systems from other members of Orbital’s family of successful launchers: Pegasus, Taurus, and Minotaur.

Taurus II is a two-stage launch vehicle that can use an additional third stage for achieving higher orbits. The payloads handled by Taurus II can have a mass of up to 5,400 kg.

Orbital is responsible for overall development and integration of the first stage. The two AJ26-62, designed and produced by Aerojet and Orbital, are powered by liquid oxygen and kerosene. The core design is driven by NPO Yuzhnoye, the designer of the Zenit launchers.

The AJ26-62 engines are basically the NK-33 engines designed by the Kuznetsov Design Bureau for the Russian N-1 launch vehicle, and remarketed by Aerojet under a new designation.

The second stage uses an ATK Castor-30 solid motor with thrust vectoring. This stage evolved from the Castor-120 solid stage.

The optional third stage is developed by Orbital. The stage was dubbed the Orbit Raising Kit (ORK) and it uses a helium pressure regulated bi-propellant propulsion system powered by nitrogen tetroxide and hydrazine. ORK evolved from the Orbital STAR Bus. Because it is a hypergolic stage, it allows several burns to be performed in orbit, and can be used for high-precision injections using various orbital profiles.

Credits: Orbital

Cygnus will only have cargo capability and will be able to deliver up to 2,300 kg of pressurized or un-pressurized cargo to the ISS. The spacecraft will also be able to return up to 1,200 kg of cargo from ISS to Earth.

The two components of the Cygnus spacecraft will be the service module and the cargo module.

The service module is based on the Orbital STAR bus (like the ORK stage), and will use two solar arrays for producing electrical power for the navigation systems onboard.

The pressurized cargo module is based on the Italian-built Multi-Purpose Logistics Module (MPLM). The un-pressurized cargo module is based on NASA’s ExPRESS Logistics Carrier.

Cygnus will not dock to the ISS in the same manner as the European ATV, but it will be able to maneuver close to the ISS where the Canadarm 2 robotic arm will be used to capture it and berth it to the Node 2 module, similar to the Japanese HTV or SpaceX’s Dragon spacecraft.

The Mid-Atlantic Regional Spaceport (MARS), located at NASA’s Wallops Island Flight Facility on Virginia’s Eastern shore, was chosen by Orbital to serve as the base of operations for the Taurus II launch vehicle.

MARS has two FAA licensed launch pads for LEO access. MARS also offers access to suborbital launchers, vehicle and payload storage, and processing and launch facilities.

Credits: NASA

Due to the location of the spaceport, latitude 37.8 degrees N, longitude 75.5 degrees W, optimal orbital inclinations for the launches performed at MARS are between 38 and 60 degrees. Polar and retrograde orbits can also be serviced with additional in-flight maneuvering.

The first flight of Orbital’s new Taurus II / Cygnus launch system under COTS is scheduled for late 2010.