The Extreme Temperatures of the Universe
For most of us, temperature is a very easy variable to overlook.
Our vehicles and indoor spaces are climate controlled, fridges keep our food consistently chilled, and with a small twist of the tap, we get water that’s the optimal temperature. Of course, our concept of what’s hot or cold is actually very narrow in the grand scheme of things.
Even the stark contrast between the wind-swept glaciers of Antarctica and the blistering sands of our deserts is a mere blip on the universe’s full temperature range. Today’s graphic, produced by the IIB Studio, looks at the hottest and coldest temperatures in our universe.
But First: What is Temperature Anyway?
Before looking at this top-to-bottom view of extreme temperatures, it helps to remember what temperature is actually measuring – kinetic energy, or the movement of atoms.
Hypothetically, atoms would simply stop moving as they reach absolute zero. As matter heats up, it begins to “vibrate” more vigorously, changing states from solid to gas. Eventually, plasma forms as electrons wander away from the nuclei.
With that quick primer, let’s dig into some of the hottest insights in this cool data visualization.
Highs and Lows on Planet Earth
Earth’s lowest air temperature, -135ºF (-93ºC), was recorded in Antarctica in 2010. Since then, scientists have discovered that surface ice temperatures can dip as low as -144ºF (-98ºC).
The conditions need to be just right: clear skies and dry air must persist for several days during the polar winter. In surroundings this cold, human lungs would actually hemorrhage within just a few breaths.
On the other end of the spectrum of extreme temperatures, the hottest surface reading on Earth of 160ºF (71ºC) occurred in Iran’s Lut Desert in 2005. In fact, the Lut Desert clocked the highest surface temperature in 5 out of 7 years during a 2003-2009 study, making it the world’s hottest location. The desert’s dark pebbles, dry soil, and lack of vegetation create the perfect conditions for blistering heat.
There are very few organisms that can withstand such temperatures, but one fascinating phylum makes the cut.
The Amazing Tardigrade
Commonly known as a “moss pig” or “water bear”, the one-millimeter long tardigrade is extremely resilient. While most organisms need water to survive, the tardigrade gets around this by entering a “tun” state, in which metabolism slows to just 0.01% of its normal rate.
When water is scarce, the creature curls up and synthesizes molecules that lock sensitive cell components in place until re-hydration occurs. Beyond dry conditions, the tardigrade can also survive both freezing and boiling temperatures, high radiation environments, and even the vacuum of space.
This video courtesy of TEDEd explains more about the hardy critter:
Testing the Limits
For better or worse, humans have pushed the limits of temperature here on Earth.
At MIT, scientists cooled a sodium gas to half-a-billionth of a degree above absolute zero. In the words of the Nobel Laureate Wolfgang Ketterle, who co-led the team: “To go below one nanokelvin (one-billionth of a degree) is a little like running a mile under four minutes for the first time.”
Not all experiments are conducted out of simple curiosity. Conventional bombs already explode at around 9,000ºF (5,000ºC), but nuclear explosions take things much further. For a split second, temperatures inside a nuclear fireball can reach a mind-bending 18,000,000ºF (10,000,000ºC).
The highest man-made temperature ever recorded is 9,900,000,000,000ºF (5,500,000,000,000ºC), created in the Large Hadron Collider at CERN in Switzerland. It was achieved by accelerating heavy lead ions to 99% the speed of light and smashing them together.
Highs and Lows of the Universe
While humans have been able to manufacture extremely hot and cold temperatures, the universe has created these extremes naturally.
Undoubtedly, the creation of the universe is made of the hottest stuff of all. The temperature of the universe at 10⁻³⁵ seconds old was a whopping 1 octillion ºC. Moments later, it “cooled down” to 1,800,000,000ºF (1 billion ºC) when the universe was less than two minutes old.
On the other end of the spectrum, the coolest natural place currently known in the universe is the Boomerang Nebula at -457.6ºF (-272ºC). It’s found 5,000 light years away from us in the constellation Centaurus, and it is currently in a transitional phase as a dying star.
As space exploration goes further than ever, these extreme temperatures may one day reach even hotter or colder heights than we can imagine.
Where Will the World’s Next 1,000 Babies Be Born?
This graphic paints a picture of the world’s population, showing which countries are most likely to welcome the next 1,000 babies.
Where Will the World’s Next 1,000 Babies Be Born?
View a higher resolution version of this map.
Every four minutes, approximately 1,000 babies are born across the globe. But in which countries are these babies the most statistically likely to come from?
Using data from the CIA World Factbook, this graphic by Pratap Vardhan (Stats of India) paints a picture of the world’s demographics, showing which countries are most likely to welcome the next 1,000 babies based on population and birth rates as of 2022 estimates.
The Next 1,000 Babies, By Country
Considering India has a population of nearly 1.4 billion, it’s fairly unsurprising that it ranks first on the list. Of every 1,000 babies born, the South Asian country accounts for roughly 172 of them.
|Place||Region||Births Per 1,000 Global Babies|
|🇨🇩 Congo, Democratic Republic of the||Africa||31.90|
|🇺🇸 United States||Americas||30.42|
|🇿🇦 South Africa||Africa||7.84|
|🇨🇮 Cote d'Ivoire||Africa||5.97|
|🇧🇫 Burkina Faso||Africa||5.41|
|🇬🇧 United Kingdom||Europe||5.37|
|🇸🇦 Saudi Arabia||Asia||3.69|
|🇸🇸 South Sudan||Africa||3.19|
|🇰🇵 Korea, North||Asia||2.71|
|🇰🇷 Korea, South||Asia||2.63|
|🇱🇰 Sri Lanka||Asia||2.35|
|🇸🇱 Sierra Leone||Africa||2.06|
|🇵🇬 Papua New Guinea||Oceania||2.04|
|🇩🇴 Dominican Republic||Americas||1.42|
|🇨🇫 Central African Republic||Africa||1.31|
|🇨🇬 Congo, Republic of the||Africa||1.30|
|🇸🇻 El Salvador||Americas||0.86|
|🇦🇪 United Arab Emirates||Asia||0.79|
|🇨🇷 Costa Rica||Americas||0.55|
|🇵🇸 West Bank||Asia||0.54|
|🇳🇿 New Zealand||Oceania||0.47|
|🇭🇰 Hong Kong||Asia||0.43|
|🇵🇸 Gaza Strip||Asia||0.41|
|🇬🇶 Equatorial Guinea||Africa||0.37|
|🇧🇦 Bosnia and Herzegovina||Europe||0.24|
|🇵🇷 Puerto Rico||Americas||0.18|
|🇲🇰 North Macedonia||Europe||0.16|
|🇸🇧 Solomon Islands||Oceania||0.12|
|🇹🇹 Trinidad and Tobago||Americas||0.11|
|🇨🇻 Cabo Verde||Africa||0.08|
|🇸🇹 Sao Tome and Principe||Africa||0.04|
|🇧🇸 Bahamas, The||Americas||0.04|
|🇳🇨 New Caledonia||Oceania||0.03|
|🇵🇫 French Polynesia||Oceania||0.03|
|🇱🇨 Saint Lucia||Americas||0.01|
|🇫🇲 Micronesia, Federated States of||Oceania||0.01|
|🇲🇭 Marshall Islands||Oceania||0.01|
|🇦🇬 Antigua and Barbuda||Americas||0.01|
|🇻🇨 Saint Vincent and the Grenadines||Americas||0.01|
|🇻🇮 Virgin Islands||Americas||0.01|
|🇮🇲 Isle of Man||Europe||0.01|
|🇲🇵 Northern Mariana Islands||Oceania||0.01|
|🇹🇨 Turks and Caicos Islands||Americas||0.01|
|🇫🇴 Faroe Islands||Europe||0.01|
|🇦🇸 American Samoa||Oceania||0.01|
|🇰🇾 Cayman Islands||Americas||0.01|
|🇰🇳 Saint Kitts and Nevis||Americas||0.00|
|🇸🇽 Sint Maarten||Americas||0.00|
|🇲🇫 Saint Martin||Americas||0.00|
|🇻🇬 British Virgin Islands||Americas||0.00|
|🇸🇲 San Marino||Europe||0.00|
|🇼🇫 Wallis and Futuna||Oceania||0.00|
|🇨🇰 Cook Islands||Oceania||0.00|
|🇸🇭 Saint Helena, Ascension, and Tristan da Cunha||Africa||0.00|
|🇧🇱 Saint Barthelemy||Americas||0.00|
|🇫🇰 Falkland Islands (Islas Malvinas)||Americas||0.00|
|🇵🇲 Saint Pierre and Miquelon||Americas||0.00|
It’s worth noting that, while India ranks number one on the list, the country’s birth rate (which is its total number of births in a year per 1,000 individuals) is actually slightly below the global average, at 16.8 compared to 17.7 respectively.
China, which comes second on the list, is similar to India, with a high population but relatively low birth rate as well. On the other hand, Nigeria, which ranks third on the list, has a birth rate that’s nearly double the global average, at 34.2.
Why is Nigeria’s birth rate so high?
There are various intermingling factors at play, but one key reason is the fact that Nigeria’s economy still is developing, and ranks 131st globally in terms of GDP per capita. Further, access to education for women is still not as widespread as it could be, and research shows that this is strongly correlated with higher birth rates.
The World’s Population Growth Rate is Declining
While there are hundreds of thousands of babies born around the world each day, it’s worth mentioning that the world’s overall population growth rate has actually been declining since the 1960s.
This is happening for a number of reasons, including:
- Increased wealth around the world, which research has correlated with fewer births
- Various government policies discouraging large families
- The global shift from rural to urban living
By 2100, global population growth is expected to drop to 0.1%, which means we’ll essentially reach net-zero population growth.
This would increase our global median age even further, which poses a number of economic risks if countries don’t properly prepare for this demographic shift.
All the Contents of the Universe, in One Graphic
We explore the ultimate frontier: the composition of the entire known universe, some of which are still being investigated today.
All the Contents of the Universe, in One Graphic
Scientists agree that the universe consists of three distinct parts: everyday visible (or measurable) matter, and two theoretical components called dark matter and dark energy.
These last two are theoretical because they have yet to be directly measured—but even without a full understanding of these mysterious pieces to the puzzle, scientists can infer that the universe’s composition can be broken down as follows:
|Free hydrogen and helium||4%|
Let’s look at each component in more detail.
Dark energy is the theoretical substance that counteracts gravity and causes the rapid expansion of the universe. It is the largest part of the universe’s composition, permeating every corner of the cosmos and dictating how it behaves and how it will eventually end.
Dark matter, on the other hand, has a restrictive force that works closely alongside gravity. It is a sort of “cosmic cement” responsible for holding the universe together. Despite avoiding direct measurement and remaining a mystery, scientists believe it makes up the second largest component of the universe.
Free Hydrogen and Helium
Free hydrogen and helium are elements that are free-floating in space. Despite being the lightest and most abundant elements in the universe, they make up roughly 4% of its total composition.
Stars, Neutrinos, and Heavy Elements
All other hydrogen and helium particles that are not free-floating in space exist in stars.
Stars are one of the most populous things we can see when we look up at the night sky, but they make up less than one percent—roughly 0.5%—of the cosmos.
Neutrinos are subatomic particles that are similar to electrons, but they are nearly weightless and carry no electrical charge. Although they erupt out of every nuclear reaction, they account for roughly 0.3% of the universe.
Heavy elements are all other elements aside from hydrogen and helium.
Elements form in a process called nucleosynthesis, which takes places within stars throughout their lifetimes and during their explosive deaths. Almost everything we see in our material universe is made up of these heavy elements, yet they make up the smallest portion of the universe: a measly 0.03%.
How Do We Measure the Universe?
In 2009, the European Space Agency (ESA) launched a space observatory called Planck to study the properties of the universe as a whole.
Its main task was to measure the afterglow of the explosive Big Bang that originated the universe 13.8 billion years ago. This afterglow is a special type of radiation called cosmic microwave background radiation (CMBR).
Temperature can tell scientists much about what exists in outer space. When investigating the “microwave sky”, researchers look for fluctuations (called anisotropy) in the temperature of CMBR. Instruments like Planck help reveal the extent of irregularities in CMBR’s temperature, and inform us of different components that make up the universe.
You can see below how the clarity of CMBR changes over time with multiple space missions and more sophisticated instrumentation.
What Else is Out There?
Scientists are still working to understand the properties that make up dark energy and dark matter.
NASA is currently planning a 2027 launch of the Nancy Grace Roman Space Telescope, an infrared telescope that will hopefully help us in measuring the effects of dark energy and dark matter for the first time.
As for what’s beyond the universe? Scientists aren’t sure.
There are hypotheses that there may be a larger “super universe” that contains us, or we may be a part of one “island” universe set apart from other island multiverses. Unfortunately we aren’t able to measure anything that far yet. Unravelling the mysteries of the deep cosmos, at least for now, remains a local endeavor.