Sometimes it’s hard to remember that NASA also does atmospheric research too. While typically thought of as the province of the National Oceanic and Atmospheric Administration (NOAA), America’s space agency also has a vested interest in exploring our atmosphere and in the technologies that enable us to do so. As such, its NASA Institute for Advanced Concepts (NIAC) program provided a Phase I grant to a team from the University of Pennsylvania to develop a novel type of propulsion using only light to collect data in the Earth’s challenging-to-explore mesosphere.
Continue reading “A new Propulsion System Could Levitate Vehicles in the Earth’s Upper Atmosphere”Light Pollution is Obscuring the Night Sky. RIP Stargazing

A citizen science initiative called Globe at Night has some sobering news for humanity. Our artificial light is drowning out the night sky for more and more people. And it’s happening more rapidly than thought.
Continue reading “Light Pollution is Obscuring the Night Sky. RIP Stargazing”Could Next-Generation Telescopes See That Earth Has Life?
While the Earth absorbs a lot of energy from the Sun, a lot of it is reflected back into space. The sunlight reflected from Earth is called Earthshine. We can see it on the dark portion of the Moon during a crescent Moon. The Farmer’s Almanac said it used to be called “the new Moon in the old Moon’s arms.”
Earthshine is one instance of planetshine, and when we look at the light from distant exoplanets, we’re looking directly at their planetshine without it bouncing off another object.
If distant astronomers were looking at Earthshine the way we look at exoplanet shine, would the light tell them our planet is rippling with life?
Continue reading “Could Next-Generation Telescopes See That Earth Has Life?”Should Planetary Defence Take Center Stage?

Throughout the Solar System, planets and moons bear the scars of a past fraught with collisions. The Moon, Mercury, and Mars are so scarred from these impacts that craters overlap one another on their surfaces. Earth was subject to the same bombardment, though most of its impact scars disappeared over time due to active geology.
But some are still visible, and we know how catastrophic some of these impacts were for life.
Continue reading “Should Planetary Defence Take Center Stage?”Earth’s Water is 4.5 Billion Years Old

The origin of Earth’s water has been an enduring mystery. There are different hypotheses and theories explaining how the water got here, and lots of evidence supporting them.
But water is ubiquitous in protoplanetary disks, and water’s origin may not be so mysterious after all.
Continue reading “Earth’s Water is 4.5 Billion Years Old”To Fight Climate Change, We Could Block the Sun. A Lightweight Solar Sail Could Make it Feasible
Can we build an enormous umbrella to dim the Sun? Such a feat would be a megaproject on a scale like no other. It would take at least 400 dedicated rocket launches a year, for ten years (There have been 172 rocket launches by all nations so far in 2022). The project would weigh in at 550,000 tons: at its lightest. And it would be an ecological experiment that puts us all – the entire planet – in the petri dish, with high risk and high reward. But could such a project actually reverse climate change and bring us back from the brink of global disaster?
The answer seems to be yes, it could work. But there are consequences, and with the planet at stake, it seems wise to examine them before committing to such a thing.
Continue reading “To Fight Climate Change, We Could Block the Sun. A Lightweight Solar Sail Could Make it Feasible”Should We Build a Nature Reserve on Mars?
There are 8 billion of us now. The UN says when the population peaks around the year 2100, there’ll be 11 billion human souls. Our population growth is colliding with the natural world on a greater scale than ever, and we’re losing between 200 and 2,000 species each year, according to the World Wildlife Federation.
An Engineer from the UK says that one way to mitigate the damage from the clash between humanity and nature is to create more habitat. We could do that by building Terran ecosystem preserves on Mars.
Continue reading “Should We Build a Nature Reserve on Mars?”OK, Artemis. Now You’re Just Showing Off. A Stunning View of the Moon Eclipsing Earth From the Orion Spacecraft
Have you ever seen a lunar eclipse of the Earth from the far side of the Moon? Now we have.
On Monday (November 28, 2022) NASA’s Orion spacecraft streamed back live video showing the Earth and Moon right next to each other, followed by a stunning view of the Moon eclipsing the Earth.
What a time to be alive! Image editor Kevin Gill might have said it best:
Continue reading “OK, Artemis. Now You’re Just Showing Off. A Stunning View of the Moon Eclipsing Earth From the Orion Spacecraft”What’s the Best Mix of Oceans to Land for a Habitable Planet?

Earth is about 29% land and 71% oceans. How significant is that mix for habitability? What does it tell us about exoplanet habitability?
Continue reading “What’s the Best Mix of Oceans to Land for a Habitable Planet?”Volcanoes are the worst. They’ve caused extinctions on Earth, and probably killed Venus

Is there anything good about volcanoes? They can be violent, dangerous, and unpredictable. For modern humans, volcanoes are mostly an inconvenience, sometimes an intriguing visual display, and occasionally deadly.
But when there’s enough of them, and when they’re powerful and prolonged, they can kill the planet that hosts them.
Continue reading “Volcanoes are the worst. They’ve caused extinctions on Earth, and probably killed Venus”