What's the closest known black to Earth as of 2025?

 If the Milky Way were a football field, the closest known black hole to Earth sits on our one-yard line. Meet Gaia BH1, a completely silent, invisible ghost just 1,560 light-years away.

Discovered in late 2022 by the European Space Agency's Gaia mission, it is located in the constellation Ophiuchus. For years, astronomers believed other objects held this title. In 2020, a system called HR 6819 was declared the closest black hole at just 1,000 light-years away, but follow-up observations proved it was a "vampire" star system with no black hole at all. As of 2025, Gaia BH1 remains the undisputed record-holder.

The reason it remained hidden for so long is its dormancy. Most black holes are discovered because they are "active"—meaning they tear apart companion stars and gorge on the resulting gas. This violent feeding process heats the gas to millions of degrees, emitting intense X-rays that space telescopes can easily spot. Gaia BH1, however, is not feeding. It emits absolutely no light or radiation.

Astronomers found it by looking at its dance partner. Gaia BH1 is locked in a binary system with a normal, Sun-like star. By analyzing data from the Gaia spacecraft, researchers noticed this star was wobbling in space, orbiting an invisible object every 185.6 days. The unseen object has a mass nearly 10 times that of the Sun—far too heavy to be a neutron star or a white dwarf. It could only be a black hole.

The Milky Way is likely teeming with these dormant black holes. In the years since finding BH1, the Gaia mission has also discovered Gaia BH2 (3,800 light-years away) and Gaia BH3 (a massive 33-solar-mass black hole about 1,926 light-years away).

While 1,560 light-years sounds far, it is practically right next door in cosmic terms. Astronomers estimate there are upwards of 100 million stellar-mass black holes wandering through the Milky Way. Given those numbers, it is a statistical certainty that an even closer, dormant black hole is out there right now, waiting to be discovered by its gravitational tug on the stars around it.

An illustration of the Gaia BH1 system, showing the dormant black hole distorting the background starlight near its Sun-like companion. Photo by International Gemini Observatory/NOIRLab/NSF/AURA/J. da Silva/Spaceengine/M. Zamani is licensed under CC BY 4.0.

Why was Sita born from the Earth and not a womb?

It's backstory is in Uttar Kand where it's written that a daughter of Sage Kushadhwaja was very beautiful and many men wanted her hand but he refused them all saying that he wanted Lord Vishnu to be her husband. A demon named Shambhu due to this killed Kushadhwaja and his wife due to grief entered fire. Unprotected Vedvati left for the woods and wore matted locks and black antelope’s skin and did penance to get Lord Vishnu as her husband.

Ravana once saw her and praised her beauty. She introduced herself and called her Vedas personified. He proposed her and called her penance unworthy as she was very beautiful and young. When she rejected his offer, he grabbed her hair which angered her. She cut her hair through her hand which magically became as sharp as blade due to her penance. She entered fire vowing to return and destroy Ravana.

She later was reborn on a lotus with fragrance of lotus. Ravana saw her and brought her in his palace but his ministers seeing her told him that she would be the reason of his destruction. Ravana got angry and threw the baby in the Sea which was taken to Mithila by the waves and when Janaka was doing ritual ploughing ,he found the baby (reborn Vedvati) in the line of ploughed field and therefore named her as Sita and adopted her as his child. He gave her to his Queen and reborn Vedvati became Sita, Princess of Mithila.

Ironically, if Ravana had not thrown the baby despite his ministers warning him, Sita would not be brought up by Janaka but Ravana. But, he was unworthy to become father of Mahalakshmi and therefore she chose Rajrishi Sheerdhwaj Janaka as her father and fate played it's course.

Source- Uttar Kand, Valmiki Ramayana

What is the deadliest place on Earth?

 The deadliest place in the world can be measured in different ways:

1. Most gruesome death
2. Fastest death
3. Fundamentally hostile to life

For a gruesome death, I would recommend a final cannonball into Lake Irazú in Costa Rica. This lake is an acidic crater lake where a gruesome death is guaranteed!

In my opinion, the candidate for the fastest death is the Kilauea volcano in Hawaii. This volcano can reach temperatures well over 1000°C, which guarantees an exceptionally quick death.

Finally, I would like to mention the coldest places in the world, since cold makes life impossible. The cold brings chemical processes to a standstill, thus halting all forms of life. One such place is the Pole of Cold, a high plateau in eastern Antarctica where temperatures can plummet to -90°C.

Are there concrete plans to remove old satellites and debris from Earth's orbit?

 Plans were circulated, but it turns out to be a devilishly difficult problem to solve, incredibly expensive, and not as big as most people think.

Most satellites are properly disposed of these days. Satellites in low Earth orbit either re-enter the atmosphere on their own due to air resistance or are intentionally removed from their orbit towards the end of their lifespan. Satellites in geosynchronous orbits are moved to a graveyard orbit where they cannot interfere with active satellites.

However, this doesn't mean that debris isn't a problem. Everything from loose cameras to paint splatters is floating around in Earth's orbit, and all of these things can be deadly if they hit an astronaut or satellite at orbital speeds.

The problem with collecting debris in space is that the large objects are easy to detect and avoid, while the really small objects - which can still be deadly - are extremely difficult to detect and therefore difficult to capture with a debris-collecting satellite.

The low-hanging fruit—which we'll probably do first—is moving satellites that die prematurely. When a satellite is placed into a geosynchronous orbit, the plan is always to move it to a graveyard orbit at the end of its life, but if the satellite dies prematurely, it's stuck where it is. If we could launch a cheap shuttle that would attach itself to the dead satellite and move it to the graveyard orbit where it was meant to end up, that might be worth considering.

It's worth noting that every single graphic that attempts to show the "crowded" space around the Earth is misleading. Consider images like this one:

...and this...

These images give the impression that we can barely squeeze in another satellite. The problem is that each of these graphics massively overestimates the size of the satellites.

A typical satellite is about the size of an SUV, but in the second image above, it's depicted as if all the satellites were the size of the greater Atlanta area. In the first image, the satellites are the size of several countries. I understand why they do this—if they showed the satellites to scale, you wouldn't be able to see them—but most people take these graphics at face value.

Space debris is not yet a crisis, but it is something we need to think about, and thankfully some people are.

What are some mind-blowing facts about the planet Earth?

 Earth hides oceans locked in solid rock and a metal core burning as hot as the Sun. Yet if you shrank the planet to the size of an apple, the atmosphere would be thinner than its skin.

This fragile envelope of life-supporting gas is incredibly shallow. Looking at photographs taken from the International Space Station, you can see this boundary as a razor-thin, glowing blue line separating the planet's surface from the deep black vacuum of space. The troposphere, which contains about 75% of the atmosphere's mass and almost all of its water vapor, extends only about 5 to 12 miles (8 to 20 kilometers) above the surface—a mere fraction of the planet’s 7,917-mile (12,742 km) diameter.

The thin blue line of Earth's atmosphere separates the planet from the darkness of space, as photographed from the International Space Station with the Moon in the background. Source: Wikimedia Commons.

Beneath this thin shell lies a planet of extremes and hidden reservoirs:

• An "ocean" locked in stone: Deep within the Earth’s transition zone, between 250 and 410 miles (410 to 660 kilometers) below the crust, lies a vast reservoir of water. It is not a liquid sea, but rather water molecules chemically bound inside the crystal structure of a rare, high-pressure mineral called ringwoodite. If this transition zone is fully saturated, it could hold as much water as all of Earth's surface oceans combined.
• A lumpy gravity field: Earth’s gravity is not uniform. Because the planet’s mass is distributed unevenly due to deep mantle convection currents and the uneven thickness of the crust, gravity varies by location. For instance, parts of Canada's Hudson Bay region have lower gravity than surrounding areas, a remnant of the last ice age when thick glaciers compressed the crust, which is still slowly rebounding.
• The driest place is frozen: While the Sahara and Atacama deserts are famous for their dryness, the driest place on Earth is Antarctica's McMurdo Dry Valleys. These ice-free valleys have extremely low humidity, and powerful katabatic winds sweeping down from the mountains at speeds up to 200 mph (320 km/h) evaporate any snow. Some sections of these valleys have not seen rain or snowfall in nearly two million years.
• A solid furnace: Earth's inner core is a solid sphere of iron and nickel with temperatures reaching up to 6,000 °C (10,800 °F)—matching the surface temperature of the Sun. Despite being hot enough to melt any known metal, the pressure at Earth's center—about 3.6 million times atmospheric pressure—squeezes the atoms so tightly that they cannot transition into a liquid state.
• A planetary thermostat: Earth is the only known planet in the solar system with active plate tectonics. Beyond shifting continents, this process acts as a global thermostat through the carbonate-silicate cycle. Subducting plates carry carbon dioxide locked in rocks deep into the mantle, while volcanoes release it back into the atmosphere, stabilizing Earth's climate over millions of years.

What is the strangest place on Earth?

 Not many people can claim hell as their birthplace.

But Todd Domboski and the few thousand former residents of Centralia, Pennsylvania, come closest to that distinction.

Signs warn visitors of the dangers of death by suffocation or being swallowed by the ground, but the old mining town of Centralia, Pennsylvania, was once home to more than 1,000 people.

Now it is nothing more than a smoldering ghost town that has been burning for half a century.

It started with a fire that was intentionally set to burn out a landfill for Labor Day in 1962.

The problem was that the dump was also an old mine connected to a maze of abandoned underground mine tunnels full of coal.

Although the city managed to extinguish the fire above ground, a much larger inferno burned beneath it, eventually making its way under the city center of Centralia.

The fire was so widespread, destructive, and endless—it is said that there is enough coal underground to stoke the fire for another 250 years.

- that in 1980 a $42 million plan prompted most residents to move (most houses were demolished), leaving only about a dozen survivors behind.

What place on Earth would be more inhospitable to human life?

 Unexpectedly, it's neither the Sahara Desert, nor the icy plains of Antarctica, nor the dangerously deadly Amazon rainforest…

Ladies and gentlemen, I present to you Rannoch Moor , in the heart of Scotland.

Rannoch Moor is only six kilometers in diameter and doesn't seem so bad. But a few years ago, one of those crazy people who want to conduct survival experiments decided to challenge Rannoch Moor.

See that beautiful hut? Well, that's where they found 29-year-old David Austin, dead from hypothermia after trying to survive on Rannoch Moor.

The problem with this place is that it's very flat and open. And worse: the ground isn't solid. It's an area full of moss, where you'll walk through muddy swamps and soggy marshes.

There's nowhere to rest. There are no trees. There's no dry land. And if you try to cross Rannoch Moor even a little bit faster than normal, you're quite likely to badly twist your ankle.

What are some unusual natural phenomena that can be observed on Earth?

 Everyone dies, but it's such a rare event that it only happens once in a lifetime to anyone or anything. I think death is the rarest phenomenon that can ever occur to any being.

In the case of humans, death is extremely rare, and once it occurs, we are wiped off the face of the Earth, but I think we are simply transforming into some other kind of energy.

In nature, there are phenomena that restore what has been destroyed.

The same thing happens to us. We don't die; we simply change to adapt. Nature wastes nothing, not even waste.

I believe death is one of the greatest phenomena that occur in nature.

Edward Bohren, Shipwreck, Namibia

What are the places on Earth that are inaccessible to humans?

 This is Gangkhar Puensum, the highest unclimbed mountain in the world at 7,570 meters. No one in history has ever reached the summit, and likely no one will for a long time.

The mountain is located in Bhutan, which has banned climbing for religious reasons, so reaching the summit is not only physically difficult, but also legally impossible.

The highest peak in this category is Muchu Chhish in Pakistan, at 7,453 meters, an incredibly challenging mountain that has only been climbed twice in history.

As a species, we have been both to the Moon and to the deepest part of the ocean, but there are still several dozen mountains around the world whose peaks have never been reached by anyone, making them perhaps the most difficult places to reach on the entire planet.

What is the deadliest place on Earth?

 The deadliest place in the world can be measured in different ways:

1. Most gruesome death
2. Fastest death
3. Fundamentally hostile to life

For a gruesome death, I would recommend a final cannonball into Lake Irazú in Costa Rica. This lake is an acidic crater lake where a gruesome death is guaranteed!

In my opinion, the candidate for the fastest death is the Kilauea volcano in Hawaii. This volcano can reach temperatures well over 1000°C, which guarantees an exceptionally quick death.

Finally, I would like to mention the coldest places in the world, since cold makes life impossible. The cold brings chemical processes to a standstill, thus halting all forms of life. One such place is the Pole of Cold, a high plateau in eastern Antarctica where temperatures can plummet to -90°C.

What is the most difficult place on Earth to invade?

 Take a look at this seemingly unremarkable building, which could be a company headquarters or a multi-tenant building.

The true purpose of this building is something you would never guess from its unassuming exterior.

Have you ever heard the phrase, "All the gold bullion in Fort Knox"? The Federal Reserve Bank of New York holds far more gold bullion than Fort Knox. That's $250 billion worth, or 7,000 tons of gold bullion.

The United States owns only a small portion of it; most of it belongs to foreign central banks and international organizations.

Considering who owns some of the most valuable things in the world, this building must have some special features that justify their trust. Shall we take a peek inside?

First of all, the building is guarded by armed security guards, and the perimeter is constantly monitored by security cameras.

If you manage to slip past that, the next stop is the underground vault 24 meters deep where the gold bars are stored. The only passage leading up to it is a single 90-ton steel cylinder surrounded by a 140-ton steel and concrete frame. This passage is usually tilted at a 90-degree angle and is blocked by four iron bars until opening hours.

Outside of business hours, this passageway is sealed to such an extent that neither water nor air leaks out, and a person would suffocate in three days.

Once you pass through here, you will finally reach the inside of the vault. The vault room is under the same 24-hour surveillance as the building, plus it is equipped with motion sensors.

Congratulations! Now, let's take your gold bars. The gold bars are stored in separate compartments for each of the 122 account holders. Each compartment requires two combination locks, one padlock, and the auditor's seal. Unlocking each compartment requires three people: two New York Fed employees and one internal auditor. No single employee knows how to open all the locks.

Now, you finally have the gold bars in your hands. Each bar weighs a little over 12 kilograms, and there are more than 500,000 of them in total. Shall we make our escape now? But it won't be that easy. You'll have to go back through that tube, but it will probably be tilted 90 degrees or filled with New York City police officers who are dying to meet you.

Shall we start digging underground? The vault, like the passageway, is surrounded by a steel and concrete frame, and as a key part of the security system, it's equipped with a device that detects vibrations underground. Of course, we'll be digging in the heart of Manhattan, a place that's sure to attract a lot of attention.

There has never been a physical attempt to enter this building. This speaks volumes about how tightly this place is protected. Even if a brave challenger were to appear, it would undoubtedly end in mere "attempt."

Where are some of the most abandoned places on earth?

 1.Ross Island, Andaman

2.Fatehpur Sikri, Agra

3.Shettihalli Church, Karnataka

4.Jamali Kamali Tomb, Delhi

5. The Last House on Holland Island – U.S.A.

6. House of the Bulgarian Communist Party – Bulgaria.

7. Nara Dreamland – Japan.

8.The Jet Star Rollercoaster, Seaside Heights – New Jersey.

9.The 102-Year-Old Floating Forest in Sydney – Australia.

10.Abandoned Train Station, Abkhazia – Georgia

11.Underwater City in Shicheng – China.

12.Abandoned Soviet submarine base.

If you ever find yourself on the set of a post-apocalyptic movie almost scared to death, then there’s a possibility that you might have entered a real life abandoned Soviet submarine base left from the Cold war – an enormous building scoured by ocean tides and haunted by hulking machines, slowly rusting away.

13. A vending machine, brought inland by the catastrophic 2011 tsunami, in an abandoned rice field in Fukushima – Japan.

14.Bare footprints embedded forever in an abandoned nuclear reactor.

15.An Abandoned Mill – Sorrento, Italy.

Content Credits: inyminy.com,Namaste: Lets Walk Through India