The biggest event in the universe, in terms of shaping everything we know, is the Big Bang, the moment ~13.8 billion years ago when space, time, matter, and energy began from an infinitely hot, dense point. While the Big Bang started everything, currently observed massive events include immense galaxy cluster mergers, ultra-powerful gamma-ray bursts (GRBs), and the feeding of supermassive black holes, like the Ophiuchus Supercluster eruption, which released unimaginable energy.
In gamma-ray astronomy, gamma-ray bursts (GRBs) are extremely energetic events occurring in distant galaxies which represent the brightest and most powerful class of explosion in the Universe. These extreme electromagnetic emissions are second only to the Big Bang as the most energetic and luminous phenomena known.
In 1 sextillion years (10²¹ years), the universe will be a vastly different, dark place: the era of star formation will have ended, all stars will have burned out into white dwarfs, neutron stars, or black holes, planets will be cold and lifeless, and even protons might begin to decay, leading towards the "Big Freeze" or heat death, with only black holes slowly evaporating via Hawking radiation over unimaginable timescales. All familiar structures, including galaxies, will have long dissolved as the universe expands, leaving behind a cold, dark, and nearly empty expanse.
About 95% of the universe is "invisible" because it's composed of dark matter (around 27%) and dark energy (around 68%), which don't emit, absorb, or reflect light, unlike the normal matter (stars, planets, us) that makes up the visible 5%. Dark matter's presence is inferred through its gravitational pull on visible galaxies, while dark energy is a mysterious force causing the universe's accelerated expansion.
In Big Bang cosmology, the Planck epoch or Planck era is the earliest stage of the Big Bang, before the time passed was equal to the Planck time, tP, or approximately 10−43 seconds.
The magnitude of this scale factor (nearly 300,000 kilometres or 190,000 miles in space being equivalent to one second in time), along with the fact that spacetime is a manifold, implies that at ordinary, non-relativistic speeds and at ordinary, human-scale distances, there is little that humans might observe that is ...
The unseen repellant force required to explain this observation has been labelled “dark energy,” and current models say it makes up about 68% of the Universe. That leaves only 5% of the Universe that is visible to us.
Space, or outer space, is a vast, near-perfect vacuum largely devoid of matter. This vacuum contains very few particles compared with Earth's atmosphere. However, it's not entirely empty. Space is dotted with scattered matter called the interstellar medium, which includes hydrogen and helium atoms.
We are extremely confident black holes exist due to overwhelming evidence like stars orbiting invisible, super-massive objects (Sagittarius A*), gravitational waves from merging black holes detected by LIGO, and direct imaging of their shadows by the Event Horizon Telescope (EHT). While "100% sure" is rare in science, the consistency between Einstein's relativity, observed phenomena, and these new direct proofs leaves virtually no doubt within the scientific community.
As defined by the International Astronomical Union (IAU), a light-year is the distance that light travels in vacuum in one Julian year (365.25 days). Despite its inclusion of the word "year", the term is not a unit of time.
Finally, the planet will likely be absorbed by the Sun in about 7.5 billion years, after the star has entered the red giant phase and expanded beyond the planet's current orbit.
The Sun has about 5 billion years left of stable life as a main-sequence star, but it will become too hot for life on Earth much sooner, potentially in 1 to 1.5 billion years, as it gradually brightens. Eventually, the Sun will swell into a red giant, engulfing the inner planets, before shrinking into a white dwarf that slowly fades, ending its life cycle over trillions of years.
The Bible does not directly address the age of the Earth or the universe. The number of 6000 years came from Archbishop Ussher in the 17th century.
T Coronae Borealis nova 2025: bottom line
During the eruption, the star will temporarily rival the brightness of the North Star! This is possibly a once-in-a-lifetime experience – the next time T Coronae Borealis will brighten up won't be for another 80 years.
Once every 176 years, the giant planets on the outer reaches of the solar system all gather on one side of the sun, and such a configuration was due to occur in the late 1970s.
This is why TON 618 is so interesting to astronomers: with an ultramassive black hole of 66 billion solar masses, it lies above King's estimate of the maximum limit (50 billion solar masses) for a non-spinning black hole.
Black Holes. Find out why we can't see them! At the center of most galaxies is one of the strangest and deadliest things in the universe: a black hole.
One minute near a black hole can equal years, decades, or even millennia on Earth due to extreme gravitational time dilation, where time slows drastically as gravity intensifies; the exact duration depends on the black hole's mass and your proximity to its event horizon, with the effect becoming almost infinite at the horizon itself, making an observer seem frozen to someone far away, though time still passes normally for the person falling in.
By analyzing the frequencies of gravitational waves from a merger between two black holes, the team verified Stephen Hawking's 1971 black-hole area theorem, which states the total surface area of black holes cannot decrease.
But eventually, the lack of oxygen will take its toll. One by one, your major organs will shut down. After only a handful of minutes you will suffer complete organ failure, otherwise known in the medical community as death.
Return to the Moon
Artemis II, scheduled for launch between February and April sees the return of the first people to the Moon since Apollo 17 in 1972. Three American and one Canadian astronaut will orbit the Moon on a 10 day journey that lays the foundation for lunar landings in the coming years.
Unfortunately, the answer is "not very long at all." Within just 10 to 15 seconds, a person in space without a spacesuit would fall unconscious due to a lack of oxygen. Even if they held their breath, their lungs would expand and rupture before their blood and other bodily fluids began to boil, causing massive damage.
These are the first words in the Bible: “In the beginning God created the heavens and the earth” (Genesis 1:1). Everything that exists has been created by God. This means the full expanse of the universe was created by God.
Looking toward the sun we thus see a brilliant white light while looking away we would see only the darkness of empty space. Since there is virtually nothing in space to scatter or re-radiate the light to our eye, we see no part of the light and the sky appears to be black.
The universe is approaching the midpoint of its 33-billion-year lifespan, a Cornell physicist calculates with new data from dark-energy observatories. After expanding to its peak size about 11 billion years from now, it will begin to contract – snapping back like a rubber band to a single point at the end.