Loft Orbital — an infrastructure company that flies customer payloads and/or technology as a service
In 2017, the commercial company Loft Orbital Inc. started with a mission to be the fastest and simplest path to orbit for any space mission. To achieve this vision we've built a team that combines the best of aerospace, hardware and software, hailing from all over the world, with diverse professional background and perspectives. While the trust our customers have placed in us is always top of mind, we never forget to have fun! 1)
Our mission is to be the fastest, simplest, and most reliable path to orbit for any payload. We fly customer payloads onboard regularly scheduled satellites missions, and we handle the entire mission as a service. With Loft, our customers can focus on what matters most to them: their payload and the data it collects.
Under the hood, we've developed the software and hardware products that make our satellite missions truly plug and play, eliminating years of painful design and engineering. With qualified, commodity satellite buses procured in advance and available off-the-shelf, we deliver payloads to orbit in months not years.
About Loft Orbital: Loft Orbital deploys and operates space infrastructure as a service, providing rapid, reliable, and simplified access to orbit for customer missions. The company has developed modular hardware and software products that enable any payload to fly on any commodity satellite bus. By remaining payload-agnostic and holding these satellite buses in inventory, Loft Orbital is able to deliver unprecedented speed-to-orbit without compromising reliability or schedule for even the most demanding customer payloads.
Loft Orbital offers an end-to-end service that delivers your mission to orbit on a standard microsatellite bus. The company handles all elements of a satellite campaign from end to end - booking, launching and operating a satellite as well as securing the necessary licenses, insurance, and financing.
The company was founded by Alex Greenberg, Antoine de Chassy, and Pierre-Damien Vaujour, in San Francisco, California.
First launch of Loft Orbital YAM microsatellites on the Transporter-2 rideshare mission of SpaceX
• June 28, 2021: A small US company with a business model that involves bundling a mix of customer payloads on prefabricated satellite buses expects to mark its first launch tomorrow (29 June). 2)
- San Francisco-based Loft Orbital describes its YAM-2 (Yet Another Mission) and YAM-3 satellites - as “rideshare satellites”. About 100 kg each, they are carrying a total of 10 payloads from customers that include European satellite operator Eutelsat and the United Arab Emirates Space Agency, plus Loft Orbital’s own instruments with which it will serve multiple customers.
- The satellites are among 88 onboard SpaceX’s Transporter-2 flight, itself the company’s second designed specifically as a rideshare. In another sign of the times, it is also the eighth flight for this particular Falcon 9 booster. Originally scheduled to launch 25 June from Cape Canaveral Space Force Station, Florida, SpaceX delayed the launch to give “additional time for pre-launch check outs”.
- Started in 2017, Loft Orbital spent its first couple of years developing hardware and software, hiring staff and meeting with “hundreds of customers” to refine the company’s business plan, chief operating officer Alex Greenberg told ROOM.
- The idea, which Loft Orbital is now demonstrating for the first time, was to invent an adapter of sorts - its Payload Hub “hosting environment” - to easily mount numerous payload types on an on-hand inventory of buses from outside vendors such as Blue Canyon Technologies and LeoStella. YAM-2 and YAM-3 represent one of each.
- According to Greenberg this model should give customers “the ability to fly very quickly”. He said the aim was to “make space simple” so that any kind of organization can get a payload into orbit and receive data back without the customary time or expense of designing a new satellite from scratch. “It’s all baked into Loft’s product set,” Greenberg added.
- YAM- 2 and YAM-3 include internet-of-things experiments and panchromatic, multispectral, and hyperspectral imagers among other payloads. If a customer can’t provide its own payload, Loft Orbital will help to supply one off the shelf.
- Loft Orbital developed its customer interface Cockpit in-house. Customers go to Cockpit to request tasks for their payloads. Cockpit calculates whether a task is within the scope of the mission and returns the desired data.
- Loft Orbital works out deals with its customer for the appropriate level of service, Greenberg said - how often they can expect to take a picture of a given location, for example - to make sure one satellite can accommodate everything on it.
- A challenge included figuring out how to give customers the ability to control their individual payloads while keeping the underlying platform secure, Greenberg added.
- Loft Orbital owns and operates the satellites. A customer may also ride as the sole payload and YAM-4 will be a standalone experiment by the Canadian Space Agency in quantum key distribution, Greenberg added.
Figure 1: Artistic rendering of Loft Orbital YAM-2 (right) and YAM-3 (left) microsatellites in space (image credit: Loft Orbital)
Development status and events
• January 14, 2022: Condosat operator Loft Orbital has ordered more than 15 satellite buses from Airbus in a deal announced Jan. 14 that calls for building the initial OneWeb-derived platforms in France before shifting serial production to Florida. 3) 4)
- Loft Orbital expects to receive the buses in 2023, leveraging the automated production line that Airbus is using to build hundreds of satellites for OneWeb’s broadband megaconstellation under the Florida-based Airbus OneWeb Satellites joint venture.
- Work to modify the Arrow satellite platform, including extending operational life and broadening the range of capabilities beyond broadband, will initially take place at Airbus facilities in Toulouse, France.
- After building the first few in France, Airbus said the remaining Arrow-derived platforms would be made at scale by Airbus OneWeb Satellites (AOS). The joint venture’s automated production line in Merritt Island, Florida, was designed to produce up to two satellites per day.
- Even with Airbus expected to fulfill most of Loft Orbital’s order out of the Florida factory, the contract is a solid win for France, according to a senior French government official quoted in the Airbus news release.
- “I am very pleased that the project presented by Loft with the support of Airbus relies on French suppliers, more than 60% of the value being created in France,” Bruno Le Maire, French minister for the Economy, Finances and the Recovery, said in the news release.
- San Francisco-based Loft Orbital buys satellite buses from multiple vendors and outfits them with payloads flown on behalf of customers looking to avoid the hassle and expense of owning satellites.
- Loft Orbital co-founder and CEO Pierre-Damien Vaujour said that, while the company plans to use its initial Arrow procurement “to deliver to our customers who have ordered services based on a few tens of satellites, we see this as an opportunity to offer much larger constellation services to governments and companies worldwide.”
- He told SpaceNews in an interview that the Arrow-derived bus will become its “workhorse satellite platform” as it leverages the AOS factory’s scalability and heritage.
Figure 2: An artist view of the Arrow platform (image credit: Airbus)
- The AOS announcement comes shortly after Loft Orbital said it had ordered additional buses from LeoStella, after securing undisclosed customers looking to fly payloads in 2023.
- LeoStella was already under contract to build a bus for a satellite that Loft Orbital plans to deploy in the first half of this year. A separate Loft Orbital satellite slated to launch toward the end of 2022 will use a bus supplied by Blue Canyon Technologies.
- Loft Orbital is currently flying two condosats with buses built by LeoStella and Blue Canyon.
- According to Vaujour, Loft Orbital’s deal for Arrow marks the first time a mass-manufactured megaconstellation bus has been sold to a commercial third party for flying non-broadband payloads.
- “It’s a completely different scale compared to everything we or the industry have done before,” he said.
- Vaujour said Loft Orbital expects to take delivery of the Arrow-derived buses in 2023, using at least some of them for satellites slated to launch later that year on behalf of a backlog of customers.
- “We’ve secured well in excess of $100 million of bookings,” Vaujour said, adding that Loft Orbital had been “turning down customers because we just don’t have enough bandwidth.”
- He said the Arrow contract also has options “with set prices where we can just trigger a purchase order for any number of additional satellites.”
- Plans to scale up Loft Orbital’s business with a rush of satellite bus orders come after the company secured $140 million in a funding round completed in October and led by investment giant BlackRock.
Florida factory future
- Loft Orbital’s order provides some backlog for a Florida factory facing uncertainty after OneWeb executives made conflicting statements about where it intends to build its planned second generation of satellites. In early December, OneWeb’s head of government affairs said the company, which is partially owned by the British government, planned to open a U.K. factory to build the second-gen satellites. The following week, OneWeb’s chief technology officer said no decision had been made.
- The first six of OneWeb’s first-generation satellites were built in Toulouse, before moving serial production to AOS in Florida. With 394 OneWeb satellites now in orbit, AOS is building 254 more to complete the 648-satellite constellation OneWeb expects to have in orbit before the end of the year.
- An Airbus official in the U.S. told SpaceNews it has “no plans to close the Florida factory.” The $85 million facility, located near major NASA and U.S. Space Force launch facilities in Cape Canaveral, Florida, opened in 2019.
- “We remain committed to supporting OneWeb’s future endeavors including Generation 2 satellites and those of our US Government and industry customers,” the Airbus U.S. official said via email. “Airbus will continue to use its manufacturing hubs in the US, France and the UK to be a leading provider of satellites and their payloads for the global market.”
- The Airbus U.S. official said AOS is also “performing on other subcontracts to Airbus for our US government and industry customers.”
- These include work on two satellite buses for the Blackjack LEO constellation, under a contract the Defense Advanced Research Projects Agency (DARPA) awarded Canadian operator Telesat last year.
- Sara Shell, public relations manager for Space Florida, the State of Florida’s aerospace economic development agency, said she could not go into details about the facility’s future because of non-disclosure agreements with both OneWeb and Airbus.
- However, she said: “It is safe to say that Space Florida is confident the facility here at the Cape will continue to produce satellites for multiple customers for many decades into the future.”
• August 9, 2021: The space industry needs to significantly simplify services for customers outside the sector to unlock its next phase of growth, space executives told the Small Satellite Conference Aug. 9. 5)
- New space-as-a-service (SaaS) business models have vastly expanded the market, offering more customers the benefits of space infrastructure without the burdens of satellite manufacturing, launch, regulations or other technical intricacies.
- SaaS offerings from companies including Spire Global, SSTL, Momentus and Loft Orbital Solutions — which participated in a Northern Sky Research panel for the virtual conference, aim to lower barriers to entry for companies lacking in-house expertise to develop space services.
- They also promise to significantly speed up the time it takes these customers to launch their services.
- But many SaaS offerings are still being provided to organizations that consider themselves as a space company, with a keen interest in all its technical details.
- “They want to deploy some satellites so they can then build a business around the data coming off of it,” explained Theresa Condor, executive vice president and general manager for space services and Earth intelligence at satellite operator Spire Global.
Figure 3: An artist's rendering of Loft Orbital's YAM-3 satellite, which used a bus from LeoStella (image credit: Loft Orbital)
• June 24, 2021: SpaceX is getting set to launch scores of satellites for its Transporter-2 rideshare mission, and one of those satellites marks a milestone for LeoStella. 6)
- Loft Orbital’s satellite, known as YAM-3 (“Yet Another Mission-3”), is the first of its kind built for San Francisco-based Loft Orbital by LeoStella, a joint venture between BlackSky and Thales Alenia Space.
- All of the satellites previously shipped out from LeoStella’s factory in Tukwila, Wash., were built for BlackSky’s Earth observation constellation.
- “This is the first satellite LeoStella has delivered to a customer other than BlackSky,” Brian Rider, LeoStella’s chief technology officer, told GeekWire in an email. “LeoStella successfully tailored its core production satellite as a multi-mission bus to support Loft, on a very different payload and mission. Loft is our first customer for which we applied this approach.”
- YAM-3 will host a variety of payloads — including a demonstration for the Defense Advanced Research Projects Agency’s Blackjack satellite constellation program, and an Internet of Things telecom payload for Eutelsat. The satellite is part of a broader contract that calls on LeoStella to build and integrate satellite buses for several upcoming Loft Orbital missions.
Figure 4: A team of company engineers pose for an image of the YAM-3 spacecraft (image credit: LeoStella)
Figure 5: Loft Orbital’s satellite, known as YAM-3, is the first of its kind built for San Francisco-based Loft Orbital by LeoStella, a joint venture between BlackSky and Thales Alenia Space (video credit: LeoStella)
- “We’ve been impressed by the LeoStella team’s agility and dedication, and we’re looking forward to expanding our partnership for future missions,” Pierre-Damien Vaujour, Loft Orbital co-founder and CEO, said in a news release. “Now that our Payload Hub is fully compatible with LeoStella’s product, our upcoming missions will be even more reliable and delivered to orbit even faster.”
- Loft Orbital and BlackSky aren’t LeoStella’s only customers: Since its founding in 2018, the joint venture has also made deals with NorthStar Earth and Space and Cloud Constellation Corp. for satellite design and assembly. Rider said the approach developed for Loft Orbital could be used for other satellites.
• January 6, 2021: Condosat operator Loft Orbital has ordered another batch of small satellite buses from LeoStella after securing undisclosed customers looking to fly payloads in 2023. 7)
- The companies declined to discuss how many buses were ordered, but Loft Orbital CEO Pierre-Damien Vaujour told SpaceNews that customers have already fully booked one of them and another is “partially full.” Both of those satellites are targeting a launch in the first half of 2023.
- Vaujour said: “We always try to procure satellite buses before we have customers, but we keep running into the issue of needing more satellites buses, because we see more customer demand than anticipated.”
- San Francisco-based Loft Orbital is building a small fleet of multipurpose satellites to carry payloads and provide services on behalf of companies that do not want the hassle or expense of buying or flying their own satellites.
- LeoStella primarily builds satellites for its part-owner BlackSky, an Earth observation operator, but also sells products including its LEO-100 commercial off-the-shelf satellite bus to third parties.
- The Jan. 6 announcement from Loft Orbital that it ordered multiple LEO-100 buses from LeoStella comes soon after the company raised $140 million in a funding round led by investment giant BlackRock.
- “Now that we have more capital, we anticipate placing a large order of buses soon to build inventory in order to resolve this issue and be able to address our customer needs,” Vaujour said, adding that the company will seek to procure buses from multiple partners.
- Boulder, Colorado-based Blue Canyon built the satellite bus for the YAM-2 satellite that launched on a SpaceX rideshare mission in June, and for YAM-4 that is counting down to a launch in the fourth quarter of 2022.
- LeoStella, a joint venture between BlackSky Holdings and Europe’s Thales Alenia Space, built the bus for Loft Orbital’s YAM-3 satellite that launched on the same rideshare mission as YAM-2 in June 2021, as well as for the YAM-5 that plans to launch in the second quarter of 2022. Note: Leostella of Seattle, WA, was founded on the vision to reinvent satellite constellation development and manufacturing. 8)
- French satellite operator Eutelsat and the U.S. Defense Advanced Research Projects Agency (DARPA) are among YAM -3’s customers.
- YAM-5 has been fully booked for some time, added Vaujour, who said customers include one of the top 10 largest companies by market capitalization, a large civil space agency, a U.S. prime contractor and a connectivity provider for small devices.
- “While we can’t disclose any individual use case, most of the use cases we are seeing revolve around AI and Autonomy applications,” he said.
- Brian Rider, chief technology officer at LeoStella, told SpaceNews that pandemic-related supply chain and operational issues “have not significantly slowed satellite production” that it aims to ramp up this year.
- “The fact that we operate in a continuous manufacturing model allows us to build in a schedule buffer between our supply chain parts and production need dates,” Rider said.
- “We expect to keep that buffer wherever possible to ensure our production line continues uninterrupted.”
• December 10, 2020: Hydrosat, a company planning to create a thermal infrared map of Earth, announced an agreement Dec. 9 with Loft Orbital to launch its first satellite mission in early 2022. 9)
- Under the agreement, Hydrosat’s first multi-spectral infrared mission will launch on Loft Orbital’s YAM-6 spacecraft aboard a SpaceX Falcon 9 rocket. The mission, called VanZyl-1, will provide the first commercial space-based thermal imagery to track water stress, assess wildfire risk and support agricultural monitoring, according to Hydrosat CEO Pieter Fossel.
- “We are building the world’s first commercial infrared satellite constellation capable of measuring temperature,” Fossel said in a statement. “Until now, thermal infrared has been the sole domain of government programs. We are demonstrating that a highly accurate capability can be delivered commercially at low cost.”
- Washington-based Hyrdosat was founded in 2017 to provide geospatial data to commercial and government customers. San Francisco-based Loft Orbital, also founded in 2017, offers microsatellite missions as a service by integrating customer payloads with standard satellite buses and mission operations software.
- “We chose Loft Orbital because of their flexibility and end-to-end approach,” Fossel said. “Loft is a fantastic partner for us because of their ability to remove risk from the system and deliver value on the satellite bus and launch services. We look forward to working with them as we deliver game-changing data and analytics to the agriculture market and to address climate change.”
- Hydrosat’s VanZyl-1 is named for Hydrosat co-founder Jakob van Zyl, who died in August. Before co-founding Hydrosat, van Zyl worked at the NASA Jet Propulsion Laboratory, where he served as associate director for project formulation and strategy and solar system exploration director. “There is no better way for us to honor our friend’s legacy than with this space mission,” Fossel said.
- Loft Orbital planned to launch its first satellite, Yet Another Mission (YAM-2), in mid-2020 prior to the COVID-19 pandemic. That mission is now expected to launch in early 2021. Loft Orbital shelved YAM-1, a demonstration mission, to make way for operational flights.
• May 2, 2019: Loft Orbital, a company preparing a constellation to carry payloads for customers who don’t want to operate their own satellites, has filled up its first satellite and booked a January 2020 launch through Spaceflight Industries. 10)
- San Francisco-based Loft Orbital will carry five customer payloads on its first mission, designated YAM-2, Alex Greenberg, Loft Orbital co-founder and head of operations, told SpaceNews. Greenberg said the satellite will launch aboard an Indian Polar Satellite Launch Vehicle to low Earth orbit.
- Greenberg said the YAM-2 satellite will use a chassis from Blue Canyon Technologies, and has a mass slightly under 100 kilograms. Customers on the mission include hyperspectral imaging startup Orbital Sidekick, blockchain startup SpaceChain, and a UAE government agency, he said. Greenberg declined to identify the other two customers for YAM-2, but said one is an established geostationary satellite operator.
- Pierre-Damien Vaujour, Loft Orbital co-founder and head of product, said a second “condosat” is 85 percent filled with customers, and a third is 15 percent booked.
- Greenberg said YAM stands for “Yet Another Mission,” and represents what the company hopes will be the start of an escalating launch cadence. Loft Orbital is aiming for three or four satellites in orbit by the end of 2020, he said. The company envisions a higher launch rate following those early spacecraft.
- “We are thinking about three or four satellites a quarter on a given launch, which could mean about 10 satellites a year,” Vaujour said. “That’s pretty much where we want to be by the end of 2021.”
- Loft Orbital does have a YAM-1 mission planned, Vaujour said, but he declined to give details on that mission.
- Vaujour said Loft Orbital doesn’t have a target constellation size. Some prospective customers are discussing systems that would require upward of 40 satellites, he said.
- Greenberg said Fugro, a Netherlands-based geologic data company that generated 1.65 billion euros ($1.84 billion) in revenue last year, has a payload launching on a future Loft Orbital satellite, but doesn’t have current plans for more than a tech demo mission.
- Loft Orbital doesn’t build satellites, but is developing a payload hub to serve as a universal adapter to fit customer payloads inside different spacecraft buses. Greenberg said Loft Orbital is outsourcing the hardware for the hub, but writing all the software that will enable payloads to interface with their host satellite.
- Vaujour said the company is working closely with Blue Canyon Technologies of Boulder, Colorado, Surrey Satellite Technology Limited in the U.K., and Luxembourg-based OHB LuxSpace on making the payload hub compatible with their satellite platforms.
- “We are very rigid about not redesigning the satellite for each mission,” Greenberg said. “We use the same family of satellite designs for all the missions we will ever do.”
- Greenberg said Loft Orbital settled on a target mass of around 100 kg for each satellite. The customers Loft is seeking typically have payloads between 5 and 10 kg, a range Vaujour said often makes them too large for a CubeSat but not big enough to warrant a stand-alone microsatellite.
- Loft Orbital consists of about 20 people, and envisions growing to 25 to 30 by the end of the year, Greenberg said. The company raised $3.2 million in 2017, and last year unveiled a network of 21 partners across the launch, manufacturing, ground segment and analytics sectors. Vaujour said Loft Orbital has modestly expanded that partner network by adding SSTL and OHB LuxSpace, but intends to strengthen existing partnerships rather than continue adding partners.
• March 1, 2019: Mike Hettich has finally completed his transition from chief learning officer to chief executive officer at LeoStella, the satellite manufacturing joint venture headquartered here. 11)
- Hettich came to LeoStella from Kirkland, Wash.-based Astronics Advanced Electronic Systems, where he served as vice president for 19 years.
Figure 6: LeoStella satellite venture hands over CEO reins to aerospace executive Mike Hettich (image credit: LeoStella)
- For the past few weeks, he’s been learning the ropes at the Tukwila development and manufacturing facility from Chris Chautard, who stepped down from the CEO post and is returning to his home base at Thales Alenia Space in France. In an interview, Hettich joked that “chief learning officer” came the closest to describing his role during the transition.
- Today marked Hettich’s first day as LeoStella’s CEO.
- LeoStella is a 50-50 joint venture of Thales Alenia Space, a French-Italian aerospace venture, and Seattle-based Spaceflight Industries. The company was created as part of a $150 million deal involving the two companies plus Italy’s Telespazio.
- Its top priority is to build satellites the size of filing cabinets for BlackSky, a subsidiary of Spaceflight Industries that is developing a constellation of Earth-observing satellites as well as a software platform to deliver satellite imagery and other sorts of geospatial intelligence.
- Two of BlackSky’s Global satellites, built before LeoStella entered the picture, have already been put into orbit. LeoStella’s team is finishing up the work on the next two satellites, and then the company will turn out 20 more satellites for the constellation.
- BlackSky aims to have 16 satellites in its constellation by early 2021, and eventually build up the orbiting array to a full complement of 60 satellites. The satellites are designed for a service life of 36 months, which means LeoStella will have to replenish satellites over the life cycle.
- Hettich said LeoStella has lined up other satellite business as well, although he declined to provide details about the customers. About 34 employees are currently working at the venture’s headquarters, located in a Tukwila office park, and a good number of them focus on spacecraft design.
- “A lot of the press has talked about this being a manufacturing facility,” Hettich said. “This is far beyond manufacturing. This is a turnkey facility. ... We can do from design to test.”
LeoStella’s Seattle-area satellite factory is open for business
- Because LeoStella and Thales Alenia Space serve different market niches, there’s no competition between the two ventures, according to Chris Chautard, LeoStella’s outgoing CEO.
- “However, what is unique about LeoStella is that we can dig into this huge engineering force that Thales has,” he said. “And we do that. ... Whenever we have a problem to solve, or some skill that is missing on our team, we can very easily pick up the phone and have someone in Thales help us.”
- All that collaboration makes the job easier for a chief learning officer.
- “I’ve transitioned a couple of times, where I’ve walked into a ... more troubled area, let’s say. Chris and the team have built something where I’m actually inheriting a very solid foundation. It’s not a turnaround. Everything’s in place. There is a transition, and there is a bit of ‘drinking from the firehose’ as far as just learning, but this is set up well. The team is highly skilled,” Hettich said. “This is actually a pretty smooth transition, and I have to thank Chris for that.
- “I wouldn’t have left without leaving you a good foundation,” Chautard told Hettich, with a smile on his face.
2) Amanda Miller, ”Loft offers unique satellite ‘rideshare’ opportunities,” ROOM, 28 June 2021, URL: https://room.eu.com/news/loft-offers-unique-satellite-rideshare-opportunities
3) Jason Rainbow, ”Airbus books Loft Orbital order for Florida satellite factory,” SpaceNews, 14 January 2022, URL: https://spacenews.com/airbus-books-loft-orbital-order-for-florida-satellite-factory/
”Industry first: Loft Orbital signs agreement with Airbus to
procure more than fifteen Arrow satellite platforms,” Airbus
Press Release, 14 January 2022, URL: https://www.airbus.com/en/newsroom/
5) Jason Rainbow, ”Simplification is key to space industry growth,” SpaceNews, 9 August 2021, URL: https://spacenews.com/simplification-is-key-to-space-industry-growth/
”LeoStella Delivers First Loft Orbital Satellite for
SpaceX’s Jam-Packed Rideshare Mission,” LeoStella news, 24
June 2021, URL: https://leostella.com/
7) Jason Rainbow, ”Loft Orbital orders more LeoStella satellite buses,” SpaceNews, 6 January 2021, URL: https://spacenews.com/loft-orbital-orders-more-leostella-satellite-buses/
9) Debra Werner, ”Hydrosat to fly thermal infrared mission with Loft Orbital,” SpaceNews, 10 December 2020, URL: https://spacenews.com/hydrosat-signs-with-loft-orbital/
10) Caleb Henry, ”Loft Orbital fills first condosat, preps for quarterly launches,” SpaceNews, 2 May 2019, URL: https://spacenews.com/loft-orbital-fills-first-condosat-preps-for-quarterly-launches/
”LeoStella satellite venture hands over CEO reins to aerospace
executive Mike Hettich,” LeoStella, 1 March 2019, URL: https://leostella.com/
The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (firstname.lastname@example.org).