Propulsion
Propulsion glossary term

Specific Impulse (Isp)

A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate.

Propulsion Also: Specific Impulse (Isp), specific-impulse-isp, Isp, isp Has Dossier → 8 sources

01 Definition

A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds.

02 Detailed_Analysis

A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds. A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds.

03 Key_Facts

  • A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate
  • Higher Isp means less propellant for a given delta-v
  • Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds
  • Related Concepts: Fusion Driven Rocket, Plasma Propulsion

04 Deep_Dive_Intelligence

Overview

A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds.

Role: Glossary term: Specific Impulse (Isp)

Entity Type: Concept — Specific Impulse (Isp) is a technical concept or theoretical framework.


Technical Definition

A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds.


Related Concepts: Fusion Driven Rocket, Plasma Propulsion

06 Related_Terms (2)

07 Related_Entities (4)

08 Timeline_Mentions (10)

1958

Project ORION Active

The Air Force and NASA engage in Project ORION, a classified effort to develop external nuclear pulse propulsion using fission-driven pulse units. The program involved prominent physicists and enginee

defense-programs
1965

Project ORION Terminated

Project ORION is terminated primarily for political reasons, ending early research into external pulsed plasma propulsion despite promising technical results.

historical-context
1967

Malmstrom AFB ICBM shutdown (March 16, 1967): 10 missiles off-line, 'red pulsating oval 30 feet' over gate, Salas witness, 'signal sent to missiles'

10 ICBMs simultaneous shutdown. Lt. Salas DMCCC. 'Red pulsating oval, 30 feet.' Guard screaming, weapons drawn. 'Signal sent to missiles.' 'National security incident.' No explanation. 2025 Pentagon c

uap-research
1972

Astron experiment funding cancelled at LLNL

16-year project ends without achieving field reversal. Compact torus concept disperses to spheromak and FRC research.

historical-context
1973

Christofilos Astron experiment cancelled at LLNL

17-year Astron project ends. Field reversal concept disperses to LANL (FRC) and LLNL/PPPL (spheromak).

historical-context
1995

Fission Plasma Propulsion Research

R.A. Gerwin, R.A. Nebel, and D.I. Poston present research on using spheromak configurations for magnetic control of gas-core fission plasma propulsion at the 31st AIAA Joint Propulsion Conference.

fusion-physics
1999

EPPP and GABRIEL Framework Proposed

NASA researchers propose External Pulsed Plasma Propulsion (EPPP) and the GABRIEL evolutionary framework as a viable path for human exploration beyond Mars.

fusion-physics
2006

AFRL DPF paper (Feb 2006): 'pulsed-train plasmoid weapons,' 'gravity or time-distorting devices,' Q=3-6 overunity, gigawatts — the smoking gun

AFRL paper ADA446973. Aneutronic p-B11 DPF fusion. Q=3-6 → gigawatts. Explicitly mentions 'plasmoid weapons' and 'gravity/time-distorting devices.' SSTO military aerospace vehicle. MHD propulsion. Tim

uap-research
2009

MSNW ELF thruster and NASA FRC propulsion

MSNW LLC's FRC-based ELF thruster with NASA funding.

propulsion-physics
2009

M2P2 Propulsion Prospects Analyzed

Kelly A. Wallenstein evaluates Mini-Magnetospheric Plasma Propulsion (M2P2), a concept by Robert Winglee using plasma to inflate magnetic sails.

fusion-physics
View Full Timeline →

09 FAQ

What is Specific Impulse (Isp)?
A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate. Higher Isp means less propellant for a given delta-v. Fusion propulsion concepts target Isp of 10⁴-10⁶ seconds.
Why does Specific Impulse (Isp) matter?
A measure of rocket propulsion efficiency, defined as thrust divided by propellant mass flow rate.
How does Specific Impulse (Isp) relate to other concepts?
Specific Impulse (Isp) is closely related to Fusion Driven Rocket, Plasma Propulsion. These relationships are documented in the research glossary and cross-referenced with primary source documents.
When did Specific Impulse (Isp) appear in the research timeline?
Specific Impulse (Isp) is referenced in 10 timeline events, including "Project ORION Active" (1958). The timeline provides chronological context for the development and application of this concept.
Which entities are associated with Specific Impulse (Isp)?
4 entities are associated with Specific Impulse (Isp) in the network graph, including MSNW LLC, Fusion Driven Rocket (FDR), Salt Typhoon / APT28 (GRU). Explore the network graph for full relationship mapping.
Is there a detailed dossier for Specific Impulse (Isp)?
Yes, Specific Impulse (Isp) has a comprehensive intelligence dossier with deep dive analysis, source documents, and network connections. View the full dossier for complete intelligence assessment.