CosmicReplay: Space News, Deep Space & Astronomy

A tiny black hole glowing faintly against the infant universe, dense knots of hot gas collapsing around it in the first second after the Big Bang

Black Holes & Singularities

Nov 8, 20269 min read

Are Primordial Black Holes Dark Matter?

Born in the first second of the universe, primordial black holes could be the dark matter. In 2026 the case narrowed sharply. One hiding place is left.

Cosmic Replay

An eight-rotor octocopter drone flying over vast orange sand dunes on Titan, with ringed Saturn low on the hazy horizon

Missions

Nov 6, 20269 min read

Why NASA Is Flying a Nuclear Drone to Titan

NASA's Dragonfly is an 875-kg nuclear octocopter launching in July 2028 to fly Titan's dunes and sample the chemistry before life. Here’s why it has to fly.

Cosmic Replay

A glowing spherical map of the cosmic microwave background in orange and blue, with a large deep-blue cold patch low on the sphere

Cosmic Mysteries

Nov 1, 20269 min read

The CMB Cold Spot: A Cold Case 20 Years On

A ten-degree patch of the Big Bang’s afterglow sits 70 microkelvin colder than it should. Twenty years on, no suspect fully explains it.

Cosmic Replay

A large vintage radio telescope dish under a dense Milky Way sky at night, with glowing blue radio waves rippling upward from the dish into the stars

Cosmic Mysteries

Oct 30, 20269 min read

The Wow! Signal at 50: Still Unexplained

The Wow! Signal was a 72-second burst in 1977 that never repeated. A 2025 re-analysis made it stronger and sharper, and telescopes will listen again in August 2027.

Cosmic Replay

Venus as a glowing golden crescent of thick swirling sulfuric acid clouds seen from orbit, the Sun flaring just beyond the planet’s limb against black space

Terraforming & Sci-Tech

Oct 25, 202610 min read

Terraforming Venus: The Harder, Hotter Twin

Venus is Earth’s twin in size and gravity, but its surface is a 465°C pressure cooker. Terraforming it means shading the planet, burying its CO2, and importing water.

Cosmic Replay

A white Orion-style crew capsule with extended solar array wings approaching a tall stainless-steel lunar lander test vehicle in low Earth orbit, the curved blue limb of Earth glowing below against a starfield

Missions

Oct 23, 20267 min read

Why Isn't Artemis III Going to the Moon?

Artemis III was supposed to return astronauts to the Moon. Instead, four astronauts will spend two weeks in Earth orbit, rehearsing the docking the landing depends on.

Cosmic Replay

The Milky Way as a small glowing blue-white spiral galaxy drifting alone in an immense dark cosmic void, vast empty black space stretching in all directions with only a few faint distant galaxies at the far edges

Cosmic Mysteries

Oct 21, 20268 min read

Do We Live in a 2-Billion-Light-Year Void?

The KBC Void is a proposed 2-billion-light-year underdensity around our galaxy, 20% thinner than average. Fresh data says it could solve the Hubble tension.

Cosmic Replay

A Martian colony at dawn: domed habitats and a glowing geodesic greenhouse lit amber against a butterscotch sky, three astronauts in white EVA suits walking between modules, red dust drifting low over volcanic hills

Terraforming & Sci-Tech

Oct 18, 202610 min read

A Sol on Mars: One Day in a Martian Colony

One Martian sol, 24 hours and 39 minutes, through butterscotch dawns, greenhouse breakfasts, dusty EVA walks, and blue sunsets: daily life on Mars, hour by hour.

Cosmic Replay

A sleek unbranded futuristic car hovering above wet pavement at night, brilliant compressed-air thruster plumes erupting from its sides like rocket exhaust under a star-filled black sky with neon cyan rim lighting

Missions

Oct 16, 20269 min read

The Flying Roadster: Real Rocket Science

Tesla’s new Roadster flew over its own lineup on cold-gas thrusters borrowed from orbital flight. Here’s what the hover demo proved, and what it didn’t.

Cosmic Replay

A small black hole with a glowing orange accretion ring where the Sun should be, background starlight bending around it, with a tiny blue Earth in the distance

Black Holes & Singularities

Oct 13, 20268 min read

What If the Sun Became a Black Hole?

Would Earth fall in? No, its orbit would not change at all. But with the Sun’s light gone, our planet would freeze solid within months.

Cosmic Replay

Mars mid-transformation, red desert blending into blue oceans and green land under orbital mirrors

Terraforming & Sci-Tech

Oct 12, 20269 min read

How to Turn Mars Into Earth: A Blueprint

From super-greenhouse gases to an artificial magnetosphere, here is the engineering sequence scientists have proposed to make Mars habitable.

Cosmic Replay

A vast swarm of solar collector satellites encircling a sun-like star

Cosmic Mysteries

Oct 12, 20266 min read

Dyson Spheres: Alien Megastructure Search

In 1960, Freeman Dyson described how to find alien civilizations: look for the waste heat of star-sized machines. Sixty-six years later, the hunt just got interesting.

Cosmic Replay

A giant black hole shadow surrounded by a blazing orange accretion disk

Black Holes & Singularities

Oct 11, 20266 min read

The Biggest Black Holes in the Universe, Ranked

Ranked: TON 618 (41-66B Suns) leads the giants, Phoenix A may reach 100B, Holmberg 15A* and S5 0014+81 (40B each), M87* (6.5B), Sgr A* (4.3M). How each was weighed.

Cosmic Replay

A lone Earth-like planet beneath a vast, silent spiral galaxy, the cosmic loneliness of the Fermi paradox

Cosmic Mysteries

Oct 11, 20267 min read

The Fermi Paradox: Where Is Everybody?

The galaxy should be crawling with civilizations. Seventy-six years after Fermi asked the question over lunch, the silence is still deafening.

Cosmic Replay

A tiny lightsail spacecraft riding a giant laser beam toward distant stars

Missions

Oct 11, 20267 min read

Project Starshot: Sailing to Alpha Centauri

A gram-scale chip riding a laser-pushed sail could reach another star system in twenty years. The physics checks out: the engineering is the adventure.

Cosmic Replay

Starlight stretched into streaks spiraling down into a black hole interior

Black Holes & Singularities

Oct 11, 20266 min read

Inside a Black Hole: The Singularity Problem

Past the event horizon, our best theories collapse into contradiction. Firewalls, fuzzballs, and wormholes, a tour of physics’ most guarded secret.

Cosmic Replay

An orange ring of plasma around a black hole shadow with a bright flare on its edge

Black Holes & Singularities

Oct 8, 20269 min read

EHT Films a Hot Spot Orbiting Sagittarius A*

A sequence of polarized images captures a blob of plasma circling our galaxy’s central black hole every 70 minutes, just outside the horizon.

Cosmic Replay

Telescope domes on a desert mountain under the Milky Way with a laser guide star

Cosmic Mysteries

Oct 7, 20269 min read

Fast Radio Burst Repeats Every 16 Days

FRB 20180916B keeps firing on schedule from a spiral galaxy 500 million light-years away. New data rules out the simplest explanations.

Cosmic Replay

Artist impression of a hazy blue ocean planet orbiting a red dwarf star

Cosmic Mysteries

Oct 5, 20269 min read

A Sharper Spectrum of K2-18 b

Fresh transmission data tightens constraints on methane and carbon dioxide in the atmosphere of the sub-Neptune 124 light-years away.

Cosmic Replay

Towering orange gas pillars of the Carina Nebula against a blue starfield

Missions

Oct 4, 20268 min read

JWST Reveals Star Nurseries in Carina

New near-infrared mosaics expose hundreds of previously unseen protostars and jets carving through the walls of the Carina Nebula.

Cosmic Replay

A deep field image full of distant galaxies and lensing arcs

Black Holes & Singularities

Oct 3, 20269 min read

JWST Spots "Naked" Black Hole Seeds

Several galaxies at redshift 10+ host black holes far too heavy for their stars, supporting the theory that some formed directly from collapsing gas clouds.

Cosmic Replay