---
title: "NASA discovers Mars once had more water than the Earth’s Arctic Ocean"
description: "A huge primitive ocean covered one-fifth of the red planet's surface, making it warm, wet and ideal for alien life to gain a foothold."
date: "2015-03-06"
modified: "2015-08-13"
authors:
  - name: "Andreea Popescu"
    link: "https://futurism.com/authors/andreeathecat"
url: "https://futurism.com/nasa-discovers-mars-once-had-more-water-than-the-earths-arctic-ocean"
categories:
  - "Astronomy"
  - "Mars"
  - "NASA"
  - "Space"
tags:
  - "space"
---

# NASA discovers Mars once had more water than the Earth’s Arctic Ocean

![Default Futurism featured image](<https://futurism.com/wp-content/uploads/2025/10/Futurism-Filler-Image.jpg>)

- The huge body of water spread over a fifth of the planet’s surface, as great a portion as the Atlantic covers the Earth, and was a mile deep in places. In total, the ocean held 20 million cubic kilometres of water, or more than is found in the Arctic Ocean, the researchers found.
- Unveiled by Nasa on Thursday, the compelling evidence for the primitive ocean adds to an emerging picture of Mars as a warm and wet world in its youth, which trickled with streams, winding river deltas, and long-standing lakes, soon after it formed 4.5bn years ago.
- The view of the planet’s ancient history radically re-writes what many scientists believed only a decade ago. Back then, flowing water was widely considered to have been a more erratic presence on Mars, gushing forth only rarely, and never forming long-standing seas and oceans.