In simple terms
A ballistic missile burns its rocket motor for only the first part of the journey. After that it is a thrown object, following the curve that gravity gives it.
The Arms Control Association puts it plainly: ballistic missiles are powered by rockets initially but then follow an unpowered, free falling trajectory toward their targets.
How it works
Flight comes in three phases. In the boost phase the motor burns and the hot exhaust is easy to spot; the US Missile Defense Agency says this window lasts one to five minutes.
The midcourse phase follows, much of it above the atmosphere, and can last as long as 20 minutes. The warhead then reenters the atmosphere in a very short terminal phase, the last chance to stop it.
Missiles are grouped by range. Short range reaches under 1,000 kilometers, medium range 1,000 to 3,000, intermediate range 3,000 to 5,500, and intercontinental missiles travel more than 5,500 kilometers.
Why it matters
Because the arc is set early in flight, a ballistic missile arrives fast and high. Defending against one means striking a small object moving at enormous speed.
Ballistic missiles are also the main way nuclear weapons would be delivered, which is why their spread is governed by arms control treaties and export controls.
Where you’ll see it
- Reports of missile launches and interceptions
- Arms control and nonproliferation negotiations
- Defense budget debates over interceptor systems
- Satellite launch coverage, which uses related rocket technology
Example
The Arms Control Association counted 31 countries in possession of ballistic missiles as of its August 2023 review, nine of them known or suspected to hold nuclear weapons.
Often confused with
A cruise missile is not ballistic. It keeps its engine running and flies low like a small aircraft, steering all the way to its target.
Key facts
- Ballistic missiles are powered by rockets initially but then follow an unpowered, free falling trajectory toward their targets.1
- Range classes are short range under 1,000 km, medium range 1,000 to 3,000 km, intermediate range 3,000 to 5,500 km, and intercontinental above 5,500 km.1
- The Arms Control Association counted 31 countries possessing ballistic missiles, nine of them known or suspected of possessing nuclear weapons, as of August 2023.1
- The boost phase, when the motor is burning and the missile is easiest to detect and track, lasts from one to five minutes.2
- The midcourse phase can last as long as 20 minutes, while the terminal phase after reentry is very short.2
Related concepts
In the news
Quick checkWhat makes the flight of a ballistic missile ballistic?Show answer
After the rocket motor stops, it coasts unpowered along a trajectory shaped by gravity.
Sources
- Arms Control Association. Worldwide Ballistic Missile Inventories. August 2023 (accessed 22 September 2026)
- U.S. Missile Defense Agency. Ballistic Missile Defense System Elements. Undated (accessed 22 September 2026)
Editorially reviewed by Specialty Digest Editorial TeamLast reviewed September 22, 2026Researched and drafted with AI assistanceReport an issue