---
title: "Astrobiologist Explains How Invisible Aliens Could Live on Earth"
description: "Astrobiologist Samantha Rolfe has published an essay explaining how invisible aliens could already be living on Earth — and how they might have gotten here."
date: "2020-01-21"
modified: "2020-01-21"
authors:
  - name: "Kristin Houser"
    link: "https://futurism.com/authors/kristin"
url: "https://futurism.com/the-byte/astrobiologist-invisible-aliens-live-earth"
categories:
  - "Science & Energy"
tags:
  - "aliens"
  - "shadow biosphere"
  - "silicon-based life"
  - "the digest"
---

# Astrobiologist Explains How Invisible Aliens Could Live on Earth

![Astrobiologist Samantha Rolfe has published an essay explaining how invisible aliens could already be living on Earth — and how they might have gotten here.](<https://futurism.com/wp-content/uploads/2020/01/astrobiologist-invisible-aliens-live-earth.jpg>)
*\<em\>Image: Image via Pxhere/Victor Tangermann\</em\>*

## Alien Detection

During a [recent interview](<https://www.theguardian.com/lifeandstyle/2020/jan/05/astronaut-helen-sharman-this-much-i-know>) with *The Observer,* Helen Sharman, the first British astronaut, said not only that she believes [aliens exist](<https://futurism.com/the-byte/uk-first-astronaut-aliens-exist>), but also that they could be living undetected among us here on Earth.

Now, an astrobiologist has responded by detailing what form these invisible aliens might take — and how they might have gotten here.

## Shadow Biosphere

Samantha Rolfe, the principal technical officer at the United Kingdom's Bayfordbury Observatory, recently published an [essay](<https://theconversation.com/could-invisible-aliens-really-exist-among-us-an-astrobiologist-explains-129419>) in *The Conversation* responding to Sharman's alien assertions.

If Sharman is right and invisible aliens do live among us, Rolfe believes they most likely live in a microscopic "shadow biosphere."

"By that, I don’t mean a ghost realm, but undiscovered creatures probably with a different biochemistry," she wrote. "This means we can’t study or even notice them because they are outside of our comprehension."

## Cutting Carbon

Rolfe goes on to suggest that the invisible aliens could have a silicon-based biochemistry, as opposed to the carbon-based one we're familiar with.

Several research teams are already studying such alternative biochemistries, according to Rolfe, including [one from CalTech](<https://futurism.com/future-life-for-the-first-time-ever-living-cells-made-silicon-carbon-bonds>) that managed to coax living cells to bond with silicon— and if we can bring silicon to life on Earth, there's a chance silicon-based lifeforms could have evolved naturally elsewhere in the universe and hitched a ride here aboard a meteorite.

"\[W\]e do have evidence for life-forming, carbon-based molecules having arrived on Earth on meteorites," she wrote, "so the evidence certainly doesn’t rule out the same possibility for more unfamiliar life forms."

**READ MORE:** [Could invisible aliens really exist among us? An astrobiologist explains](<https://theconversation.com/could-invisible-aliens-really-exist-among-us-an-astrobiologist-explains-129419>) \[*The Conversation*\]

**More on aliens:** *[UK’s First Astronaut: Aliens Definitely Exist, May Be on Earth](<https://futurism.com/the-byte/uk-first-astronaut-aliens-exist>)*

### Author social links  
[LinkedIn](<https://www.linkedin.com/in/kristinjhouser>)