Sentinel-6A is the first of two Sentinel 6 satellites.  The second will launch in 2025.

The mission is a joint venture between NASA, the European Space Agency, the European Union, the National Oceanic and Atmospheric Administration (NOAA), the European Organisation for the Exploitation of Meteorological Satellites, and the Centre national d'études spatiales (CNES) -- the French space agency.

Both of the Sentinel 6 spacecraft will provide high-precision observations of ocean circulation and measurement of sea-level heights with accuracy to the centimeter.

Launched into a polar orbit, Sentinel 6A will join the ongoing TOPEX/Poseidon mission and the Jason constellation to provide continuous monitoring of the oceans.

The spacecraft is named in honor of Dr. Michael Freilich, the leader of NASA’s Earth Science Division until his death in August 2020 of pancreatic cancer.

Image: NASA/SpaceX/ESA

Falcon 9 is a reusable, two-stage rocket designed and manufactured by SpaceX for the reliable and safe transport of people and payloads into Earth orbit and beyond.

Falcon 9 is the world’s first orbital-class reusable rocket.

Stats

Total launches: 395

Total landings: 351

Total reflights: 326

The Falcon 9 has launched 52 humans into orbit since May 2020

Specs

Height: 70 m / 229.6 ft

Diameter: 3.7 m / 12 ft

Mass: 549,054 kg / 1,207,920 lb

Payload to Low Earth Orbit (LEO): 22,800 kg / 50,265 lb

Payload to Geostationary Transfer Orbit (GTO): 8,300 kg / 18,300 lb

Payload to Mars: 4,020 kg / 8,860 lb

On January 24, 2021, Falcon 9 launched the first ride-share mission to Sun Synchronous Orbit. It was delivering a record-setting 143 satellites to space. And while this was an important mission for SpaceX in itself, it was also the moment Falcon 9 overtook United Launch Alliance’s Atlas V for the total number of consecutive successful launches.

SpaceX’s Falcon 9 had become America’s workhorse rocket, launching 31 times in 2021. It has already beaten that record this year, launching almost an average of once a week. While most of the launches deliver Starlink satellites to orbit, the company is still launching the most commercial payloads to orbit, too.

Falcon 9 is a medium-lift launch vehicle, with the capability to launch over 22.8 metric tonnes to low earth orbit. Unlike any other rocket, its first stage lands back on Earth after separating from its second stage. In part, this allows SpaceX to offer the cheapest option for most customers with payloads that need to reach orbit.

Under its ride-share program, a kilogram can be placed in a sun-synchronous orbit for a mere 1.1 million dollars, far cheaper than all other currently operating small satellite launch vehicles.

The reusability and fast booster turnaround times have made Falcon 9 the preferred choice for private companies and government agencies. This has allowed SpaceX to capture a huge portion of the launch market.

Photo courtesy of Jenny Hautmann for Supercluster.

Space Launch Complex 4 at Vandenberg Space Force Base is SpaceX’s west coast launch and landing facility. The launch pad is named SLC-4E (as it is the easternmost of the two areas).

Satellite image of the facility and surrounding area provided by SkyFi. With mobile and web apps, SkiFi is making it easier than ever to access Earth Observation data and analytics.

Originally built in the early 1960s for Atlas-Agena rockets, SLC-4E served that rocket line until 1967, when it was taken offline and then rebuilt for the Titan IIID rockets.

It launched the Titan IIID from 1971 to 1988, after which it was reconfigured and used for the Titan IV between 1991 and 2005.

SpaceX leased SLC-4E in 2011 and spent two years rebuilding the pad for the Falcon 9 rocket.

The pad exclusively launched Falcon 9 polar missions from 2013 to 2019.  However, in 2020, SpaceX began splitting those launches between Vandenberg and Cape Canaveral after the Air Force agreed to allow polar launches from Florida after a 51-year ban (because of the then-dangers of overflying Cuba during launch).

Despite new launch opportunities from Florida, SpaceX is not abandoning Vandenberg; many more launches are planned from this location.

Landing Zone 4 (LZ-4) is SpaceX’s only west coast landing pad for the Falcon 9 first stage.

Activated in 2018, the landing pad is built on the former SLC-4W launch pad.

SLC-4W was built just 427 meters (1,400 feet) from SLC-4E for the Atlas-Agena rockets between 1963 and 1965.  After that, it was rebuilt for the Titan IIIB rocket and used for that program from 1966 to 1987.

With the Titan IIIB’s retirement, the pad was reconfigured for the Titan 23G rocket between 1988 and 2003.

SpaceX leased SLC-4W in 2015 and renamed it Landing Zone 4 and created a landing pad for the Falcon 9 rocket’s first stage.

The first Return To Launch Site landing of a Falcon 9 to Landing Zone 4 took place on October 7th, 2018.

Image: Pauline Acalin for Supercluster