Firefly Aerospace: Forging an End-to-End Path in the New Space Economy

Introduction

In the competitive landscape of the modern space industry, Firefly Aerospace has emerged as a resilient and strategically significant company. It has evolved far beyond its initial identity as a simple rocket manufacturer to become an integrated, end-to-end space transportation provider. The company’s business model now encompasses a comprehensive suite of services, including launch vehicles, in-space mobility, and lunar landing capabilities. This positions Firefly as a single-source solution for customers navigating the complexities of missions from Earth to the Moon and beyond. The company’s journey has been marked by significant challenges, including financial hardship and a dramatic restructuring, but it has persevered to become a key contractor for NASA, the U.S. Department of Defense, and major commercial clients. Its story is a compelling case study in strategic adaptation and its role in the rapidly evolving space economy is becoming increasingly defined.

A Tumultuous Ascent: The Firefly Story

The history of Firefly Aerospace is a narrative of ambition, failure, and rebirth that provides essential context for its current operational posture and strategic direction. The company’s early struggles and subsequent revival have shaped its engineering philosophy and solidified its place within the national security industrial base.

From Concept to Crisis

Firefly was founded in March 2014 as Firefly Space Systems by a team of experienced aerospace engineers and entrepreneurs, including Tom Markusic, Michael Blum, P.J. King, and Eric Salwan. The initial vision was clear: to provide affordable and reliable access to space, specifically targeting the growing market for small satellite launches. The company’s name was reportedly inspired by a moment of reflection by Markusic, who envisioned a future where frequent spacecraft launches to Mars would illuminate the night sky like fireflies.

The company experienced rapid early growth. By November 2014, it had expanded to 43 employees and moved its headquarters from Hawthorne, California, to a sprawling 215-acre site in Cedar Park, Texas, which was designated for manufacturing and engine testing. Technologically, the original Firefly Space Systems was ambitious, focusing on developing an advanced aerospike engine known as FRE-2 for its Alpha rocket. This design successfully underwent its first hot-fire test in September 2015, with the goal of carrying payloads of up to 400 kg to low Earth orbit (LEO).

However, this initial momentum was derailed by a series of severe challenges. Virgin Galactic filed a lawsuit against the company, alleging that then-CEO Tom Markusic, a former employee, had misappropriated trade secrets to start Firefly. This legal battle, compounded by the unexpected withdrawal of a major European investor, created insurmountable financial pressure. By the end of 2016, the company was forced to furlough its entire staff, halting all operations. This culminated in a Chapter 7 bankruptcy filing in April 2017, bringing the first chapter of Firefly to an abrupt and seemingly final close.

Rebirth and Realignment

The company’s assets did not languish for long. In March 2017, they were acquired at auction by Noosphere Ventures, a firm led by Ukrainian technology entrepreneur Max Polyakov. Polyakov’s substantial investment, reported to be over $200 million, was the catalyst for the company’s revival under the new name, Firefly Aerospace.

This rebirth was accompanied by a critical strategic realignment. The new leadership team undertook a major redesign of the Alpha rocket. The high-risk, technically complex aerospike engine was abandoned in favor of a more conventional and reliable tap-off engine cycle for its new Reaver and Lightning engines. This pragmatic shift in engineering philosophy, which also embraced a “simplest/soonest” approach using commercial off-the-shelf components, was a direct lesson from the previous failure. The redesign not only prioritized reliability but also more than doubled the rocket’s payload capacity, fundamentally changing its market position.

Just as Firefly was gaining momentum, it faced another defining challenge. The U.S. government, through the Committee on Foreign Investment in the United States (CFIUS), raised national security concerns over Polyakov’s ownership. As Firefly began securing sensitive contracts with the Department of Defense, the government mandated that Polyakov divest his 58% stake in the company. After a nominal sale to co-founder Tom Markusic, the stake was ultimately acquired by AE Industrial Partners (AEI), a U.S.-based private equity firm specializing in aerospace and defense, in 2022. This forced ownership change, while disruptive, was a pivotal moment. It demonstrated that as a private company’s capabilities become vital to national security, its control becomes a matter of strategic state interest. The intervention by CFIUS and the subsequent acquisition by AEI firmly aligned Firefly with the U.S. national security industrial base, strengthening its position as a trusted partner for sensitive government missions and giving it a distinct advantage in securing defense and intelligence contracts.

The Firefly Ecosystem: An Integrated Space Transportation Model

Firefly Aerospace has strategically positioned itself not merely as a launch provider but as a comprehensive, end-to-end space transportation company. This integrated business model, which combines launch, in-space mobility, and lunar services, is designed to create a competitive advantage in an increasingly crowded market.

Core Business Strategy: The End-to-End Model

The company’s strategy is built upon three core product lines: launch vehicles (Alpha and Eclipse), lunar landers (Blue Ghost), and on-orbit vehicles (Elytra). By offering a “single source for missions,” Firefly plans to simplify the complex process for customers, who would otherwise need to manage multiple vendors for launch, in-space transport, and final payload operations. This vertical integration is intended to reduce overall mission risk and cost for the customer.

A critical step in executing this strategy was the acquisition of Spaceflight Inc. in June 2023. This move was described as an “overnight game changer,” as it immediately provided Firefly with Spaceflight’s flight-proven orbital vehicles and deep expertise in mission management, including a track record of deploying over 460 payloads. This acquisition instantly bolstered the on-orbit segment of Firefly’s ecosystem, providing flight heritage and an existing customer pipeline.

This end-to-end model creates a powerful flywheel effect. Launch contracts can feed the company’s on-orbit services business, and the availability of those in-space services makes the initial launch offering more attractive. This increases the switching costs for customers; a satellite operator that uses Firefly for a complete mission lifecycle is less likely to choose a different provider for its next launch due to the seamless integration. This strategy plans to build a competitive moat in a market where launch services are becoming increasingly commoditized.

Key Partnerships and Customers

Firefly’s success is underpinned by a diverse and growing network of government and commercial partners.

Government and Defense

Firefly has become a trusted partner for the U.S. government, securing high-profile contracts that validate its capabilities.

• NASA: The agency is a primary customer, primarily through its Commercial Lunar Payload Services (CLPS) program. Firefly has been awarded multiple task orders for its Blue Ghost lunar lander missions, with contracts valued at more than $230 million. Additionally, NASA has selected Firefly’s Alpha rocket to launch key science missions, including the INCUS and QuickSounder satellites.
• U.S. Space Force: The Space Force is a key client for responsive launch services. Firefly’s VICTUS NOX mission in 2023 was a landmark achievement, setting a new national record by launching a satellite just 27 hours after receiving the official order. This demonstrated capability has led to further contracts for tactically responsive missions like VICTUS HAZE and VICTUS SOL.
• Other Agencies: Firefly also holds contracts with the National Reconnaissance Office (NRO) and the Defense Innovation Unit (DIU) for on-orbit technology demonstrations using its Elytra vehicle, further cementing its role in the national security space sector.

Commercial and Strategic Partnerships

The company has forged critical alliances with major aerospace players and has a strong manifest of commercial customers.

• Northrop Grumman: This is a cornerstone partnership for Firefly. It includes a $50 million investment from Northrop Grumman and the joint development of the new medium-lift Eclipse rocket. Firefly is also leveraging its advanced manufacturing to build the entire first stage for Northrop’s upgraded Antares 330 rocket. This symbiotic relationship provides an elegant solution for both companies. For Northrop Grumman, it solves an urgent supply chain crisis created by its reliance on Russian engines and Ukrainian structures for the original Antares rocket. For Firefly, it provides a significant capital injection, enhanced credibility, and a de-risked pathway into the lucrative medium-lift market, a venture that would be immensely challenging to undertake alone.
• Major Defense Contractors: Demonstrating strong market confidence in its Alpha rocket, Firefly has secured major multi-launch agreements with some of the largest names in defense, including a deal for up to 25 launches with Lockheed Martin and another for up to 23 launches with L3Harris.
• International Collaboration: Firefly’s reach extends globally. Its lunar missions include payloads and partnerships with the European Space Agency (ESA), the United Arab Emirates’ Mohammed Bin Rashid Space Centre, and Australia’s Fleet Space Technologies, highlighting its role as a facilitator of international space exploration.

From Earth to Orbit: Launch Vehicle Capabilities

Firefly Aerospace has developed a family of launch vehicles designed to serve distinct segments of the space transportation market. From its workhorse Alpha rocket to the next-generation Eclipse, the company’s launch capabilities are central to its end-to-end business model.

Alpha: The Workhorse Rocket

The Firefly Alpha is a two-stage, expendable launch vehicle engineered to address a specific gap in the market between dedicated small-satellite launchers and large, heavy-lift rockets. It provides a cost-effective, dedicated launch option for payloads in the 500 kg to 2,000 kg class, competing with vehicles like Rocket Lab‘s Electron and India’s PSLV.

The rocket stands 29.5 meters tall and is constructed primarily from lightweight carbon composite materials, a design choice that significantly improves its payload-to-weight ratio. Its propulsion system consists of four Reaver 1 engines on the first stage and a single Lightning 1 engine on the second stage. Both engines utilize a tap-off cycle and burn a combination of liquid oxygen (LOX) and RP-1, a highly refined form of kerosene.

In terms of performance, Alpha can lift 1,030 kg to a 300 km low Earth orbit (LEO) or 630 kg to a 500 km sun-synchronous orbit (SSO), with an advertised price point of approximately $15 million per launch. A defining feature of Alpha is its proven capability for “responsive launch.” As demonstrated in the VICTUS NOX mission for the U.S. Space Force, Firefly can prepare and launch a payload with just 24 hours’ notice, a critical capability for national security clients. This rapid turnaround is enabled by streamlined processes like their “Load and Go” fueling and the use of a Horizontal Integration Facility (HIF) for payload processing.

Firefly Alpha Specifications

Firefly Alpha Launch History

The operational maturity of Firefly is best illustrated by its launch history. The following table chronicles each Alpha mission, telling a story of iterative development, learning from failures, and achieving consistent success.

Eclipse: Scaling Up for the Medium-Lift Market

To address the needs of larger payloads, Firefly is developing the Eclipse rocket, previously known as the Medium Launch Vehicle (MLV). This vehicle represents a significant step up in capability and is being co-developed with Northrop Grumman to serve the underserved medium-lift launch market.

The Eclipse will be a substantially larger rocket than Alpha, standing nearly 59 meters tall with a wide 5.4-meter payload fairing. Like its smaller sibling, it will feature a structure made from advanced carbon composites. The first stage will be powered by a cluster of seven new Miranda engines, while the second stage will use a single vacuum-optimized Vira engine. Both engines will employ the same reliable tap-off cycle and LOX/RP-1 propellant combination as the Alpha’s engines.

The performance goals for Eclipse are ambitious. It is designed to lift over 16,000 kg to LEO, 3,200 kg to a geostationary transfer orbit (GTO), and 2,300 kg on a trans-lunar injection (TLI) trajectory. Crucially, the first stage is being designed for reusability from its inception, with plans for propulsive landings back at the launch site (RTLS), a capability pioneered by SpaceX with its Falcon 9 rocket.

Development is well underway, with the first launch scheduled for the second half of 2026 from Wallops Island, Virginia. To support this aggressive timeline, Firefly has significantly expanded its manufacturing and test facility in Briggs, Texas.

Eclipse (MLV) Specifications

This table outlines the planned capabilities of Firefly’s next-generation Eclipse rocket.

Beyond Earth’s Orbit: In-Space Services

Firefly’s ambitions extend far beyond simply launching payloads. The company is actively building the vehicles and services needed to operate in the cislunar environment, a key component of its end-to-end strategy designed to capture value in the “last mile” of space transportation.

Blue Ghost: A Commercial Gateway to the Moon

The Blue Ghost lunar lander, named after the rare Phausis reticulata firefly, is the centerpiece of Firefly’s lunar services and a flagship vehicle in NASA‘s Commercial Lunar Payload Services (CLPS) initiative. In March 2025, the lander achieved a historic milestone with its Blue Ghost Mission 1. It became the first commercial mission to execute a fully successful soft landing on the Moon, touching down safely in Mare Crisium and operating for a full lunar day. This success was particularly notable as it followed a competitor’s mission where the lander had tipped over upon arrival, highlighting the difficulty of the task.

The Blue Ghost lander is a versatile platform designed to deliver up to 240 kg of scientific and commercial payloads to the lunar surface. It is engineered to be adaptable, with future missions planned to include capabilities for surviving the harsh lunar night, deploying rovers for surface mobility, and potentially returning samples to Earth. During missions, the lander provides essential power, data relay, and thermal management for all customer payloads. The entire process, from manufacturing to mission control, is managed at Firefly’s dedicated 50,000-square-foot spacecraft facility in Cedar Park, Texas.

Firefly has already secured a manifest of annual lunar missions, positioning itself as a routine delivery service to the Moon.

• Blue Ghost Mission 2 (NET 2026): This is a complex international mission targeting the far side of the Moon. It will deliver payloads for NASA, the European Space Agency, Australia, and the United Arab Emirates. The mission will utilize Firefly’s Elytra orbital vehicle as both a transfer stage to deliver the lander to lunar orbit and as a communications relay, a necessity for operating on the far side.
• Blue Ghost Mission 3 (NET 2028): This mission will explore the geologically unique Gruithuisen Domes. It will deploy a rover and a suite of advanced NASA instruments to investigate the region’s unusual silica-rich composition, which could indicate the presence of water.

Blue Ghost Mission Payloads (Missions 1, 2, & 3)

The following table details the diverse scientific and technological payloads manifested on Firefly’s first three lunar missions, showcasing the company’s central role in advancing lunar science and enabling a future lunar economy.

Elytra: The On-Orbit Service Vehicle

Elytra, formerly known as the Space Utility Vehicle (SUV), is a family of scalable, multi-mission spacecraft that form the backbone of Firefly’s in-space services. It functions as the critical “in-space bridge,” connecting the company’s launch vehicles to final orbital destinations or to its lunar landers, thereby completing the end-to-end transportation chain. The acquisition of Spaceflight Inc. was a major catalyst for this product line, integrating their flight-proven orbital transfer vehicles and mission management expertise into Firefly’s portfolio.

The Elytra family is offered in three distinct configurations to meet a range of mission needs:

• Elytra Dawn: A lightweight and agile vehicle designed for rapid deployment on the Alpha rocket. It provides on-demand services in LEO and beyond, such as payload hosting, precise orbital delivery, and space domain awareness.
• Elytra Dusk: An enhanced version with greater power and maneuverability. It is designed for more complex missions, including rendezvous and proximity operations, and can operate in LEO, MEO, and GEO.
• Elytra Dark: The most capable vehicle in the lineup, engineered to serve as persistent orbital infrastructure. It can perform interplanetary transfers and will act as the transfer stage for Blue Ghost missions to the Moon.

These vehicles are designed to provide a wide array of on-orbit services, from simple payload delivery to more advanced applications like long-haul communications relay, lunar imaging, and, in the future, on-demand refueling and satellite de-orbiting. This positions Firefly not just as a transportation company, but as a long-term infrastructure and services provider for the burgeoning cislunar economy.

The Technology Underpinning the Vision

Firefly Aerospace’s ambitious strategy is enabled by a coherent engineering philosophy that prioritizes affordable reliability. This is most evident in its choices of propulsion systems and structural materials, which are designed to work in concert to produce capable and cost-effective vehicles.

Innovations in Propulsion: The Tap-Off Cycle

All of Firefly’s rocket engines—Reaver, Lightning, Miranda, and Vira—are based on a combustion tap-off cycle. This engine design represents a deliberate choice that balances performance with simplicity and reliability.

In any liquid-fueled rocket, propellants must be pumped into the combustion chamber under immense pressure. This is accomplished by a turbopump, a device similar in principle to a jet engine’s turbine. The tap-off cycle provides power to this turbopump in a straightforward manner. It “taps off” a small amount of the extremely hot gas generated in the main combustion chamber, channels it through the turbine to spin the pumps, and then vents the used gas overboard.

The primary advantage of this approach is its relative simplicity compared to more complex and higher-performance engine cycles like full-flow staged combustion. By using only one main combustion chamber and forgoing the need for separate pre-burners, the design has fewer parts, which can lead to higher reliability. It also allows for a “graceful” engine shutdown process, a desirable trait for future human spaceflight applications. This focus on simplicity aligns perfectly with Firefly’s “simplest/soonest” design ethos. The main engineering challenge of the tap-off cycle is that the turbine components must be constructed from highly advanced, heat-resistant materials, as they are exposed directly to the scorching temperatures of the main combustion chamber.

The Strength of Carbon Composites

A second technological pillar for Firefly is its extensive use of advanced carbon fiber composite materials. The primary structures and propellant tanks of the Alpha and Eclipse rockets, as well as the Blue Ghost lander, are all constructed from these lightweight materials.

Carbon fiber is a high-performance material made of incredibly thin, strong carbon threads woven into a fabric and then set in a durable resin. For rocketry, its most significant benefit is its exceptional strength-to-weight ratio. Carbon fiber is much lighter than the aluminum and titanium traditionally used in aerospace manufacturing. This weight reduction is critical; a lighter rocket requires less fuel to reach orbit, which means it can carry a heavier payload for the same amount of thrust. This directly translates into lower launch costs and greater mission capability. Firefly has stated that its use of composites can make its rockets up to 30% lighter than comparable vehicles.

Beyond weight savings, carbon composites are also extremely strong and stiff, allowing them to withstand the intense forces and vibrations of a launch. They also exhibit low thermal expansion, meaning they maintain their shape and strength across the extreme temperature fluctuations encountered in space. To accelerate production, Firefly has invested in its own in-house automated fiber placement machinery, allowing the company to rapidly manufacture these complex composite structures.

The combination of these two technologies reveals a deliberate engineering strategy. Firefly is not attempting to build the absolute highest-performing engine. Instead, it has chosen a reliable and simpler engine cycle (tap-off) and paired it with a highly efficient, lightweight airframe (carbon composites). The performance gains from the lightweight structure effectively compensate for a slightly less powerful engine, resulting in a launch system that is both dependable and cost-effective. This pragmatic approach directly supports the company’s core business model of providing affordable and reliable access to space.

Market Landscape and Competitive Standing

Firefly Aerospace operates in a dynamic and fiercely competitive market. Its strategy is tailored to navigate the complexities of the small and medium launch sectors while differentiating itself through a unique, integrated service model.

Navigating the Small and Medium Launch Market

The global market for small satellites is undergoing significant growth, with projections showing an expansion from approximately $7 billion in 2025 to over $33 billion by 2035. This surge is fueled by the deployment of massive satellite constellations for services like global broadband internet; the majority of deployments coming from SpaceX‘s Starlink and Amazon’s Kuiper. SpaceX and Amazon have already selected the launch providers for those mega constellations, leaving a much smaller demand for small satellite launch vehicles.

Firefly’s Alpha rocket is strategically positioned to capitalize on this trend by serving the small-to-medium payload class (500-2,000 kg).

However, this market is also becoming intensely competitive, with some analyses suggesting it is oversaturated with more than 75 companies developing launch vehicles. This environment places enormous pressure on providers to not only achieve orbit but also to demonstrate reliability and establish a consistent launch cadence to ensure long-term sustainability.

A Comparative Look at the Competition

Firefly’s competitive landscape is diverse, ranging from direct rivals in the small-lift market to the industry giants that define its upper echelons.

• Rocket Lab: As a publicly traded company with a similar end-to-end vision, Rocket Lab is Firefly’s most direct competitor. Both companies are developing integrated space solutions that combine launch vehicles with on-orbit service spacecraft (Rocket Lab’s Photon and Firefly’s Elytra). However, their strategies diverge in key areas. Rocket Lab has achieved a much higher launch frequency with its smaller Electron rocket, but Firefly’s Alpha already offers greater payload capacity. Furthermore, Firefly is aggressively moving into the medium-lift class with its Eclipse rocket, which is designed to be more capable than Rocket Lab’s forthcoming Neutron vehicle. Firefly also holds a distinct advantage in lunar services, having already successfully landed its Blue Ghost spacecraft on the Moon—a feat Rocket Lab has not yet attempted. This suggests that while Rocket Lab is competing on launch cadence, Firefly is competing on a broader and more advanced set of capabilities.
• Larger Players (SpaceX, ULA): While not direct competitors for small satellite launches, these companies set the standard for the broader launch industry. Firefly’s partnership with Northrop Grumman to develop the Eclipse rocket is a clear strategic move to challenge the market dominance of vehicles like SpaceX‘s Falcon 9 in the medium-lift category.
• Other Competitors: The space industry is a complex ecosystem that includes a wide array of players, from large satellite manufacturers like Airbus and Maxar Technologies to a host of other launch startups, all competing for a share of the growing market.

The Road Ahead: Firefly’s Future Trajectory

Firefly Aerospace is charting an ambitious course for the future, focused on scaling its operations, expanding its role in the cislunar economy, and deepening its support for U.S. national security.

Scaling Production and Operations

A primary objective for Firefly is to significantly increase its launch tempo. The company plans to ramp up production to support a cadence of six to eight Alpha launches in 2025. This requires a major expansion of manufacturing capabilities at its “Rocket Ranch” facility in Briggs, Texas.

In parallel, Firefly is broadening its launch infrastructure. The company is adding a new launch pad at the Mid-Atlantic Regional Spaceport (MARS) on Wallops Island, Virginia, which will be capable of supporting both Alpha and the much larger Eclipse rocket. Future launch sites are also planned at Cape Canaveral in Florida and potentially at the Esrange Space Center in Sweden, giving the company domestic and international launch flexibility. A central focus of the company’s efforts is bringing the next-generation Eclipse rocket to its inaugural flight by 2026 and operationalizing its first-stage reusability, a key factor for long-term cost competitiveness.

Expanding the Cislunar Economy

Firefly is positioning itself as a foundational player in the emerging economy centered around the Moon. The company is committed to flying annual Blue Ghost missions, establishing a regular and reliable delivery service to the lunar surface for a growing list of international and commercial customers.

Building on this transportation capability, Firefly has announced a new and highly strategic initiative: the Oculalunar imaging service, slated to begin as early as 2026. This service will utilize high-resolution telescopes mounted on Elytra orbital vehicles to provide detailed imaging of the Moon’s surface from lunar orbit. The stated goals for Ocula are to support future mission planning, aid in the detection of valuable resources like water ice and Helium-3, and provide surveillance capabilities for national security interests in cislunar space.

This is a particularly astute business move. By offering this service on existing, already-funded missions, Firefly can establish a new, high-margin data business with minimal initial capital outlay. This transforms the company from being just a transportation and infrastructure provider into a valuable data and intelligence provider. In the space industry, the data collected is often more valuable than the hardware that collects it. By creating one of the first commercial lunar imaging services, Firefly is positioning itself to be a primary source of high-resolution lunar data—a resource that will be critical for NASA, international space agencies, and any future commercial ventures aiming to operate on or around the Moon.

Supporting National Security

Responsive launch is a cornerstone of modern U.S. space strategy. In an era of increasing geopolitical tension, the ability to rapidly deploy, replace, or augment satellite capabilities in a crisis is considered a powerful deterrent against adversaries who might contemplate attacking American space assets.

Firefly has proven it is a leader in this critical domain. The successful VICTUS NOX mission, with its 27-hour call-up-to-launch timeline, placed Firefly at the forefront of this capability. The U.S. Space Force’s Tactically Responsive Space (TacRS) program is explicitly designed to leverage commercial partners like Firefly to provide this “on-demand” access to orbit. By offering a reliable, agile, and domestically controlled launch option, Firefly directly contributes to the resilience of the U.S. national security space architecture and fulfills a key policy objective of broadening the nation’s industrial launch base to ensure sovereign access to space.

Summary

Firefly Aerospace has navigated a difficult path from the brink of collapse to become a uniquely integrated and strategically vital company in the new space economy. Its story is one of resilience and pragmatic adaptation, having transformed itself from a specialized rocket builder into an end-to-end space transportation provider.

The company’s core business strategy is built on a comprehensive ecosystem that combines launch services with on-orbit mobility and lunar delivery. This model, supported by the workhorse Alpha rocket, the ambitious Eclipse medium-lift vehicle, the proven Blue Ghost lunar lander, and the versatile Elytra orbital vehicle, positions Firefly as a single-source solution for complex missions. This strategy is underpinned by a coherent engineering philosophy that prioritizes affordable reliability, skillfully combining the simplicity of tap-off cycle engines with the lightweight efficiency of advanced carbon composite structures.

In a competitive market, Firefly has carved out a distinct identity. It has become a trusted partner for U.S. government agencies, demonstrating record-setting responsive launch capabilities for national security and achieving a historic commercial Moon landing for NASA. The company is not just participating in the space economy; it is actively building the infrastructure for a future cislunar marketplace through its transportation services and innovative data-centric initiatives like the Ocula imaging service. By doing so, Firefly Aerospace has solidified its role as both a key enabler of commercial space development and a vital asset for ensuring national security in the contested domain of space.