Slide 1 of 13
The underground labs
Studies of the universe and its makeup generally conjure images of astronomers at telescopes, peering up at the galaxies, nebulas and stars scattered across the night sky. But to understand the decidedly less visible, but very important, parts of the universe, such as neutrinos and dark matter, scientists have to take a different approach — namely, by going underground.
Being underground givesscientists protection from most of the "noise" created by other kinds of particles entering the Earth, such as cosmic rays and other background radiation from the universe.
Of course, it is somewhat complicated to get underground, so scientists how have to get creative. Sometimes researchers work in repurposed mines. Others are required to drill big tunnels themselves to run particle accelerators or study nuclear fuel disposal.
The underground labs here are sprinkled across two continents and are seeking answers to questions such as how the universe formed, how particles can transform into other ones, and the true nature of dark matter.
SNOLABSlide 2 of 13
Sharing space with miners, SNOLAB (an expansion of the Sudbury Neutrino Observatory) lies 1.2 miles (2 kilometers) below the ground in the Vale Creighton Mine in Sudbury, Canada. While the miners are working on producing nickel, the researchers at SNOLAB are focused on astroparticle physics.
Among its many projects are several devoted to dark matter, which is a mysterious substance believed to make up most of the matter in the universe (unlike the matter that makes up Earth, humans and everything else visible in the universe). SNOLAB's PICASSO experiment, for example, is searching for a theorized particle of dark matter (called a WIMP, for weakly interacting mass particle) using freon droplets in a gel. The forthcoming Cryogenic Dark Matter Experiment plans to hunt for WIMPS in solid-state detectors constructed from germanium, which is a sort of carbon metal.Slide 3 of 13
Large Hadron ColliderSlide 4 of 13
Large Hadron Collider
Billed as the world's "largest and most powerful particle accelerator" by its parent organization the European Organization for Nuclear Research (CERN), the Large Hadron Collider is the most visible of a series of colliders located as deep as 570 feet (175 metres) in an area near Geneva, Switzerland. LHC has a 16.7-mile (27-kilometer) magnetized ring where two beams of particles can smash into each other at speeds close to the speed of light. The collisions take place close to four particle detectors around the ring. Through examining the collisions, scientists hope to learn more about how the universe was formed, and if there are unseen dimensions to space.
The particle accelerator lies in a tunnel that was originally carved out for another collider, called the Large Electron Positron collider. "The rock surrounding the LHC is a natural shield that reduces the amount of natural radiation that reaches the LHC and this reduces interference with the detectors," according to the United Kingdom's Science and Technology Facilities Council. "Vice versa, radiation produced when the LHC is running is safely shielded by 50 to 100 meters [160 to 330 feet] of rock."Slide 5 of 13
Soudan Underground LaboratorySlide 6 of 13
Soudan Underground Laboratory
An old iron mine in Minnesota hosts several detectors to learn more about fundamental particles that make up our universe. The experiments are almost half a mile (0.8 kilometers) underground and search for the nature of dark matter and interactions between neutrinos (neutral subatomic particles), among other things.
In 2011, the MINOS neutrino experiment in the lab found evidence of one kind of rare particle — a neutrino — changing into a different kind. Neutrinos are chargeless and almost massless particles that have three types: electron, muon and tau. The lab was one of two that recorded muon neutrinos changing into electron neutrinos, a world first.Slide 7 of 13
Gran Sasso National LaboratorySlide 8 of 13