NASA's Small Space Technology Program


CubeSats at NASA

The Small Spacecraft Technology Program, one of the nine programs in the Space Technology Mission Directorate, has three primary objectives:  

  1. Identify and support the development of new subsystem technologies to enhance or expand the capabilities of small spacecraft. The program seeks to develop subsystem technologies that are new and revolutionary in their impact, rather than incremental improvements of existing subsystems. The goal is to advance subsystem technologies from a readiness level of 3 (analytical and experimental critical function and/or characteristic proof of concept) to a readiness level of 5 (component and/or breadboard validation in relevant environment).                                                             

  2. Support flight demonstrations of new technologies, capabilities and applications for small spacecraft. The program seeks to demonstrate technologies that are new and capabilities that have not previously been demonstrated in space. The goal is to advance technologies and capabilities from a readiness level of 5 (component and/or breadboard validation in relevant environment) to a readiness level of at least 7 (system prototype demonstration in an operational environment).                                                                              

  3. Use small spacecraft as platforms for testing and demonstrating technologies and capabilities that might have more general applications in larger-scale spacecraft and systems. The program seeks to contribute to the full range of NASA's science and technology challenges, where demonstrations with small spacecraft can reduce the cost, risk, complexity or time required to advance the state-of-the-art.

All efforts focus on small spacecraft capabilities that are relevant to NASA's missions in science, exploration, space operations and aeronautics including those with crosscutting applications for NASA and other users.


The program’s current focus is systems for communications, propulsion, pointing, power and autonomous operations.


The program consists of four elements:

Mission Capability Demonstrations: flight demonstration projects for new mission capabilities involving both competitive contracts and directed NASA efforts.

Leveraged Investments: continuation of selected projects from Small Business Innovation Research or other programs as well as prize challenges and other initiatives.

Smallsat Technology Partnerships: collaboration between universities and NASA in technology development and demonstrations (the subject of this notice).


The first Pathfinder Technology Demonstrator (PTD-1) mission, which launched in late 2019, demonstrated a propulsion system with a water-based propellant.

What is a Small Spacecraft?

SSTP considers small spacecraft to be those with a mass of less than 180 kilograms. Some commonly accepted terms used for small spacecraft are the following:

Minisatellite, 100 kilograms or higher
Microsatellite, 10-100 kilograms
Nanosatellite, 1-10 kilograms
Picosatellite, 0.01-1 kilograms
Femtosatellite, 0.001-0.01 kilograms












A cubesat is a special category of nanosatellite. One cubesat unit (1U) has dimensions of 10 by 10 by 11 centimeters. Cubesats have been built in 1U, 1.5U, 2U, 3U and 6U sizes.

Source: National Aeronautics and Space Administration

Page Last Updated: March 11, 2019

Page Editor: Loura Hall        NASA Official: Brian Dunbar


The Science of our Mission

Collect spatially resolved measurements of plasma density irregularities in the ionosphere 

Our mission is a scientific investigation to measure plasma electron density at sub-meter level resolution. The science payload will be a fast Time Domain Impedance Probe (TDIP) designed to operate for measurements in the upper F layer, between 400 km to 800 km and will make adequate measurements in the equatorial and mid-latitude ionosphere.





Payload: Time Domain Impedance Probe (TDIP)
Science/Technology Demonstration: Astrophysics
Focus Areas: Scientific Research
Year Selected: 2017
POC: Dr. Edmund Spencer



Measurements of Plasma Properties

This project will be to design, develop and deliver a cubesat for the scientific purpose of measuring plasma electron density at meter to sub-meter level resolution. The development will

enable the study, for the first time, turbulent irregularities in the topside F region on meter to sub-meter scales.


A specialized instrument called a Time Domain Impedance Probe will be developed that can make measurements of plasma properties once every 0.35 meters for a satellite velocity of 7 km/s, which is unprecedented (By way of comparison, the state of the art to date is to make one measurement spread out over roughly 100 meters). The technology objective is to develop a fully functional cubesat specifically with power, attitude control, and telemetry specifications sufficient to support the science objective.

The cubesat will be designed to operate for measurements in the upper F layer, between 400 km to 800 km. The orbit inclination is

anticipated to be roughly 50 degrees so as to make adequate measurements in the equatorial as well as mid-latitude ionosphere. However, the cubesat will be designed and developed to be capable of operation in a circular orbit between 40 to 60 degrees inclination. The cubesat will be designed to be deployed through the NASA Cubesat Launch Initiative (CSLI) program.