Marcelo Gleiser

Two years ago yesterday, Dec. 12, nearly 200 countries came to a consensus that greenhouse emissions — mostly caused by the burning of fossil fuels — had to be drastically cut if we were to halt the planetary-changing consequences of a choking atmosphere.

Trial and error, experimentation, the understanding that some questions have complex answers or no answers at all, the notion that failure teaches, the acceptance that mistakes can actually guide you in the right direction, persistence in the face of difficulty: These are some of the everyday components of scientific research, accumulated wisdom that can serve us well in many walks of life — from how to face challenges as individuals to running corporations.

For this post-Thanksgiving week, I'd like to suggest a remarkable video produced over two decades by NASA scientists.

Satellites monitored populations of plant life on land and oceans, mapping variations of green regions of vegetation and snow cover on the North and South Poles. As seasons pass, we witness a rhythmic dance between white and green, as if the planet itself were breathing.

As Europe was being torn apart in the early 17th century by conflicts between Catholics and Protestants — that would lead to the devastating Thirty Years War in 1618 — the German astronomer Johannes Kepler wrote:

"When the storm rages and the shipwreck of the state threatens, we can do nothing more worthy than to sink the anchor of our peaceful studies into the ground of eternity."

Some 130 million years ago, when dinosaurs roamed Earth, two dead stars in a far-away galaxy collided violently, after spiraling around each other for millions of years.

The dead stars were neutron stars, exotic objects the size of Mount Everest and with the mass of the sun. Being this small and dense, the gravitational force is fierce. Someone once compared the pull of gravity near the surface of a neutron star to having all the population of Paris tied to your feet.

As a Brazilian-born scientist, it pains me to witness the devastating cuts — and proposal of future additional reductions — to the country's science funding.

The cut of 44 percent in March brought the 2017 budget for Brazil's Ministry of Science, Technology, Innovation and Communications the lowest level in 12 years. Additional cuts of about 16 percent have been proposed for the 2018 budget.

If it's true that a picture is worth a thousand words, what NASA's Cassini mission has left for us is indeed a treasure.

Launched in 1997, the mission terminated dramatically last week with the probe's final plunge into Saturn's upper atmosphere.

America seems to be a magnet for devastating hurricanes these days.

This year, Harvey came out strong with its horrific toll on parts of Texas and Louisiana. Now Irma, downgraded slightly Friday morning to a Category 4 storm from its most recent days as a Category 5, has left destruction in its wake as it plows through the Caribbean and Cuba — and is on path to hit Florida Sunday morning.

Hurricane Harvey is a devastating reminder of how helpless we are when facing nature's human-dwarfing powers.

We dig holes and barricades, build dams and create ingenious systems of canals and levees. We try to pull the brakes on natural forces, or at least tame them. These measures protect us, and we surely would be worse off without them. We have come a long way since our cave dwellings.

This has been quite a space week for Americans.

After Monday's stunning solar eclipse, Wednesday night PBS will air its two-hour documentary film about the two Voyager missions, launched 40 years ago. The Farthest: Voyager In Space, celebrates a technological and intellectual achievement rarely matched in history. Two small, nuclear-powered spacecraft have traveled farther than any other man-made machine and have forever changed our views of the solar system — and our place in it.

"Nature loves to hide."

This is how, more than 25 centuries back, the pre-Socratic Greek philosopher Heraclitus of Ephesus expressed the sense of mystery we all feel when we start pondering how the world works.

There seem to be hidden mechanisms, secret pacts between the things that make the world the world, from the smallest building blocks of matter to the neurons in our brains to the way the whole universe is stretching out in its inexorable expansion.

I entered the packed cafeteria with tray in hand, searching for the right food to eat.

Around me, hundreds of people of all ages spoke excitedly in dozens of different languages, commenting on each other's ideas, asking questions, and thinking of the next steps in their research programs.

Lunchtime at the United Nations?

On Aug. 21, a narrow, 70-mile wide swath of the United States from Oregon to South Carolina will be the stage for one of the most (if not the most) spectacular celestial events, a total eclipse of the sun.

Space.com has put together a nice informational guide, including a video and a map explaining where to go, what to expect, and how to watch it safely. This is the first total solar eclipse in America in almost 40 years. The next one in the U.S. will be on April 8, 2024.

The history of science — in particular the physical sciences, like physics and astronomy — can be told as the incremental realization that there is large-scale coherence in the universe.

By large-scale coherence, I mean that some of the same physical laws hold at scales as diverse as the atom and the galaxy, and even the universe as a whole. In a sense, the universe speaks one language and scientists act as the interpreters, translating this language in terms that humans can understand and relate to.

Let's face it: Vegetarians are a strict minority of the U.S. population.

The numbers seem to be increasing, though data from various surveys vary widely.

Sometimes, I veer off my beloved scientific topics to explore another of my passions — human endurance.

Today we address the composition of the universe, in the final essay of our trilogy on cosmic questions.

As the great German astronomer Johannes Kepler once wrote in the early 17th century: "When the storm rages and the shipwreck of the state threatens, we can do nothing more worthy than to sink the anchor of our peaceful studies into the ground of eternity."

This is the "big question" — the one that has been with us in one way or another since the beginning of history.

Every culture that we have a record of has asked the very same question: How did the world come to be? How did people and life come to be? Taken within this broader cultural context, it's no surprise that modern-day scientists are as fascinated with the question of origins as were the shamans of our distant ancestors.

I often get asked what an "expanding universe" really means.

It's confusing, and for very good reasons. So, if you are perplexed by this, don't feel bad. We all are, although cosmologists — physicists that work on the properties of the universe — have figured out ways to make sense of it. In what follows, I'll try to explain how to picture this.

In the next few weeks, we will address other bizarre cosmic questions, such as the meaning of the Big Bang and the future and material composition of the universe.

If you are going to watch The Lost City of Z expecting some sort of Indiana Jones sequel, don't bother.

In the midst of the current debate about fabricated facts, the former Microsoft CEO Steve Ballmer launched a new website, USAFacts.org, where people can go to check the numbers for themselves.

The site is mainly devoted to government spending and revenue, offering a wealth of data on many fronts, including analysis on the effectiveness of different programs.

We humans have this uncanny ability to tell time and create schemes to measure its passage.

Time is our greatest ally and our greatest enemy.

The idea that neuroscience is rediscovering the soul is, to most scientists and philosophers, nothing short of outrageous. Of course it is not.

Picture this: You are in the bathroom, doing your usual thing after breakfast, when you notice blood in the water sitting in your white, porcelain toilet.

Scared, you schedule an appointment with a gastroenterologist, who recommends a colonoscopy and a biopsy. It could be cancer, it could be a harmless colitis. But there you are, confronted, perhaps for the first time of your life, with your own mortality.

(Spoiler Alert: If you haven't watched the movie Logan and are planning to, you may want to read this essay only after you do.)

In generic heroic sagas, the hero leaves home to face numerous tribulations in a pilgrimage of the self.

The obstacles along the way are tests of the hero's strength, molding his/her character through pain and suffering. Glory, when achieved, is bittersweet, as it comes heavy with loss, usually of loved ones, family or companions. In tragic sagas, the hero pays with his/her life in the end so that others may be free.

Last week, Adam Gopnik of The New Yorker published a satirical essay, in which he wondered whether the strange reality we live in could be some kind of computer game played by an advanced intelligence (us in the future or alien).

The alliance between science and state is ancient.

Archimedes, the great Greek mathematician and inventor, designed weapons to protect the city of Syracuse from attacking Roman fleets. For thousands of years, blacksmiths developed new, more powerful alloys to make arrows and swords for their king's army.

To go to space we need math. Lots of it.

Most of us look in awe at the towering rocket ship strapped to the launching platform and forget the tremendous amount of work it took for it to get there — and, from there, to get into Earth's orbit and beyond. Engineering, math, physics, chemistry, computer science: It's all there, waiting for blast-off.

Some physicists, mind you, not many of them, are physicist-poets.

They see the world or, more adequately, physical reality, as a lyrical narrative written in some hidden code that the human mind can decipher.