Apr 18, 2017

What planets need for life

Our expert voices conversation on "How to look for alien life."

We find ourselves in a universe that appears, at first glance, ripe for life. Liquid water, abundant even in our own solar system (though most of it is hiding underneath thick icy crusts), amino acids hitching rides on comets, simple proteins found in young systems, millions upon millions of stars exactly like our sun in just the Milky Way galaxy.

By all appearances we should not be alone, and yet we don't see a single sign of anybody else, anywhere.

The chances of life appearing in the universe are obviously greater than 0 (otherwise I wouldn't be writing this and you wouldn't be reading this), but seem far, far less than 1.

What Earth got right: We can understand why planets like Mars and Venus wound up dead — too small to sustain a protective magnetic field and choking on its own oppressive atmosphere, respectively — even though they had a decent shot. But we don't fully understand the special sauce that makes life possible. So we're playing a numbers game. How many planets are out there? How many have liquid water? How many have a stable star and the right cocktail for life? It's only by obsessive, detailed observations will we crack it.

The other voices in the conversation:

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Amid racial unrest, a test at the polls

Photo: Stephen Maturen/Getty Images

Eight states plus D.C. are holding primary elections today following a week of intense protests across the country over the brutal police killing of George Floyd.

Why it matters: It's the first major test for voting since the national outcry. Concerns over civil unrest and the police — as well as the coronavirus and expanded absentee voting — could reduce the number of voters showing up in person but heighten tensions for those who do.

Axios-Ipsos poll: America’s big racial divide on police, virus

Data: Ipsos/Axios survey; Note: ±3.2% margin of error; Chart: Andrew Witherspoon/Axios

A new Axios-Ipsos poll finds that America has a massive racial gulf on each of our twin calamities — trust in police, and fear of the coronavirus.

  • 77% of whites say they trust local police, compared with just 36% of African Americans — one of many measures of a throbbing racial divide in Week 11 of the Axios-Ipsos Coronavirus Index, taken the week George Floyd was killed by a white policeman in Minneapolis.
Updated 51 mins ago - Politics & Policy

Updates: George Floyd protests nationwide

Police officers wearing riot gear push back demonstrators outside of the White House on Monday. Photo: Jose Luis Magana/AFP via Getty Images

Protests over the death of George Floyd and other police-related killings of black people continued for a seventh day across the U.S., with President Trump threatening on Monday to deploy the military if the unrest continues.

The latest: Four police officers were struck by gunfire while standing near a line in St Louis on Monday after a peaceful demonstration, Police Chief John Hayden said early Tuesday. They were all taken to hospital with non-life threatening injuries. He said a small group of people had thrown rocks and fireworks at police officers.