Skip to content

Surprising Science — October 12, 2011

Earth’s Oceans Delivered by Comets?

Using the powerful Herschel Space Telescope, scientists have found evidence that the water in Earth’s oceans could have been delivered by comets rather than asteroids.

bigthinkeditors

Sign up for the Smarter Faster newsletter

A weekly newsletter featuring the biggest ideas from the smartest people

What’s the Latest Development?

During observations made with the powerful Herschel Space Telescope last year, astronomers found frozen water on a comet called Harltey 2. More recent analysis shows that the molecular composition of the comet’s water—specifically, its deuterium-to-hydrogen ratio—matches that of Earth’s. The Hartley 2 comet comes from the Kupiter belt, a band of space rocks much larger than our solar system’s asteroid belt. Scientists will now look to other comets in the Kupiter belt to see if their composition is similar to Hartley 2.

What’s the Big Idea?

Water has been found on six comets prior to Hartley 2 but never before has the chemical composition of the water matched that of Earth’s oceans. What’s more, “the handful of water-bearing comets previously discovered, the researchers believe, came from the Oort cloud, a band of comets about a light-year away from the sun.” The Kupiter belt, which scientists believe Hartley 2 calls home, is 1,000 times closer to Earth and could explain the difference in chemical compositions.

Sign up for the Smarter Faster newsletter

A weekly newsletter featuring the biggest ideas from the smartest people

Related

An abstract composite image depicting where life began with mountainous terrain, chemical structures, and a monochrome inset of a cloudy sky.

Starts With A Bang

What was it like when life first sprang forth on Earth?

Although early Earth was a molten hellscape, once it cooled, life arose almost immediately. That original chain of life remains unbroken.

Abstract representation of the first possible molecules in a cosmic setting with a celestial body.

Starts With A Bang

What was it like when life first became possible?

Earth wasn’t created until more than 9 billion years after the Big Bang. In some lucky places, life could have arisen almost right away.

A series of images showing different types of micrometeorites recovered in the transantarctic mountains

Starts With A Bang

Harvard astronomer’s “alien spherules” are industrial pollutants

Finding alien technology on the seafloor would be truly incredible. This extraordinary claim, however, is debunked by the actual evidence.

Earth-like exoplanet

Starts With A Bang

Is K2-18b an inhabited ocean world? Don’t bet on it

Some fascinating observations of K2-18b have come along with horrendous, speculative communications. There’s no evidence for oceans or life.

breakthrough starshot

Starts With A Bang

Ask Ethan: Did we recover alien technology from the bottom of the ocean?

A Harvard astronomer went to the bottom of the ocean, claiming he recovered alien technology. But what does the science actually indicate?

Up Next

Personal Growth

Human Psychology in Space

While space exploration was once a field for engineers and physicists, psychologists are playing an ever bigger role. A new book reviews how the human psyche copes in space.