Our directory of things of interest

University Directory

Into the dark side

The Milky Way as seen over the desert of Bardenas in Spain The Milky Way as seen over the desert of Bardenas in Spain Inigocia
11 Apr
2015
Every 30 million years or so, the Earth passes through the most crowded section of the galactic disc. Mass extinction events and radical changes to the Earth’s geology follow

New research has suggested that what the Earth encounters when it enters the Milky Way’s crowded section of the galactic disc – namely dark matter – causes changes deep within the planet’s core.

‘When the Earth passes through [that part of] the disc, it might encounter dense clumps of invisible dark matter,’ says professor Michael Rampino, a biology professor at New York University, whose research shows a correlation between mass extinctions, geological change and the Earth’s orbit.

‘Dark matter is slowed by collisions with the Earth, loses energy and spirals into the Earth’s core,’ says Rampino. ‘If the particle is its own antiparticle they will annihilate each other, giving off energy.’

As the particles annihilate each other, immense heat is created in the Earth’s core. This heat triggers volcanic eruptions, mountain building, changes sea levels and can even flip the Earth’s magnetic fields.

A passage through dark matter also changes pathways for comets orbiting far from Earth in the outer Solar System. Comets that usually take orbits far from Earth can be pushed onto a collision course.

‘As well as being important on the largest scales, dark matter may have a direct influence on life on Earth,’ says Rampino. These changes apparently take place over a long time period and the professor warns that it may not be possible to predict encounters with dense clumps of dark matter.

‘We are fortunate enough to live on a planet that is ideal for the development of complex life. But the history of Earth is punctuated by large scale extinction events, some of which we struggle to explain,’ says Rampino. We can rest easy for a while though. Earth’s last journey through the disc was three million years ago.

This article was published in the April 2015 edition of Geographical Magazine

Related items

Geographical Week

Get the best of Geographical delivered straight to your inbox every Friday.

Subscribe to Geographical!

Adventure Canada

EDUCATION PARTNERS

Aberystwyth University University of Greenwich The University of Winchester

TRAVEL PARTNERS

Ponant

Silversea

Travel the Unknown

DOSSIERS

Like longer reads? Try our in-depth dossiers that provide a comprehensive view of each topic

  • National Clean Air Day
    For National Clean Air Day, Geographical brings together stories about air pollution and the kind of solutions needed to tackle it ...
    The Air That We Breathe
    Cities the world over are struggling to improve air quality as scandals surrounding diesel car emissions come to light and the huge health costs of po...
    Diabetes: The World at Risk
    Diabetes is often thought of as a ‘western’ problem, one linked to the developed world’s overindulgence in fatty foods and chronic lack of physi...
    Mexico City: boom town
    Twenty years ago, Mexico City was considered the ultimate urban disaster. But, recent political and economic reforms have transformed it into a hub of...
    Hung out to dry
    Wetlands are vital storehouses of biodiversity and important bulwarks against the effects of climate change, while also providing livelihoods for mill...

MORE DOSSIERS

NEVER MISS A STORY - Follow Geographical on Social

Want to stay up to date with breaking Geographical stories? Join the thousands following us on Twitter, Facebook and Instagram and stay informed about the world.

More articles in NATURE...

Wildlife

NGOs shine a light on the underreporting of wildlife crime…

Wildlife

Pioneering laser photography is being used by scientists on the…

Geophoto

Annual competition looks to celebrate island life in all its…

Oceans

Increasing interest in offshore aquaculture is dividing environmentalists

Energy

Well-meaning promises don’t always have positive outcomes. Marco Magrini finds…

Wildlife

The RSPB introduces a new hotline for reporting the unlawful…

Wildlife

With the death earlier this week of the world’s last…

Geophoto

The essence of street photography is its raw, unfiltered, unstaged…

Energy

For Marco Magrini, a tax on fossil fuels would be…

Wildlife

Half of animal species in world’s most biodiverse areas could…

Wildlife

Four-year project to reestablish safe breeding grounds for seabirds on…

Wildlife

First global atlas of soil bacteria reveals a small minority…

Polar

Scientists discover how shrubs are dominating the Arctic tundra

Wildlife

War and conservation have a complicated relationship, with two studies…

Climate

Why is Europe so cold right now? Marco Magrini suggests…

Wildlife

Threatened Californian owls are suffering from digesting rat poison administered…

Oceans

With the majority of the ocean still remaining undiscovered, a…

Oceans

Belize bans offshore oil extraction to protect the second longest…

Geophoto

With their horns still much-prized by poachers, will the revered…

Wildlife

Narwhals show a complex response to interaction with humans and…