Category The Universe, Exploring the Universe, Solar System, The Moon, Space, Space Travel

Gravity is one of only four forces that govern every event in the entire Universe. Gravity binds together the Universe, while electromagnetic force is responsible for light and electricity. A strong nuclear force holds together basic particles, and a weak nuclear force causes the decay of unstable atoms. These four forces may have been united during the Big Bang, emitted as one superforce bound by extremely high temperatures. As temperatures began to cool, the superforce was gradually broken down into four separate forces. All four forces are linked with special particles that act in the same way as couriers, transferring the force from one place to another. Electromagnetism and gravitation can work over large distances, but the two nuclear forces only operate on an atomic level.

In physics, the fundamental interactions, also known as fundamental forces, are the interactions that do not appear to be reducible to more basic interactions. There are four fundamental interactions known to exist: the gravitational and electromagnetic interactions, which produce significant long-range forces whose effects can be seen directly in everyday life and the strong and weak interactions, which produce forces at minuscule, subatomic distances and govern nuclear interactions. Some scientists hypothesize that a fifth force might exist, but these hypotheses remain speculative.

Each of the known fundamental interactions can be described mathematically as a field. The gravitational force is attributed to the curvature of space-time, described by Einstein’s general theory of relativity. The other three are discrete quantum fields, and their interactions are mediated by elementary particles described by the Standard Model of particle physics.

Within the Standard Model, the strong interaction is carried by a particle called the gluon, and is responsible for quarks binding together to form hadrons, such as protons and neutrons. As a residual effect, it creates the nuclear force that binds the latter particles to form atomic nuclei. The weak interaction is carried by particles called W and Z bosons, and also acts on the nucleus of atoms, mediating radioactive decay. The electromagnetic force, carried by the photon, creates electric and magnetic fields, which are responsible for the attraction between orbital electrons and atomic nuclei which holds atoms together, as well as chemical bonding and electromagnetic waves, including visible light, and forms the basis for electrical technology. Although the electromagnetic force is far stronger than gravity, it tends to cancel itself out within large objects, so over large distances (on the scale of planets and galaxies), gravity tends to be the dominant force.

Many theoretical physicists believe these fundamental forces to be related and to become unified into a single force at very high energies on a minuscule scale, the Planck scale, but particle accelerators cannot produce the enormous energies required to experimentally probe this. Devising a common theoretical framework that would explain the relation between the forces in a single theory is perhaps the greatest goal of today’s theoretical physicists. The weak and electromagnetic forces have already been unified with the electroweak theory of Sheldon Glashow, Abdus Salam, and Steven Weinberg for which they received the 1979 Nobel Prize in physics. Progress is currently being made in uniting the electroweak and strong fields within what is called a Grand Unified Theory (GUT). A bigger challenge is to find a way to quantize the gravitational field, resulting in a theory of quantum gravity (QG) which would unite gravity in a common theoretical framework with the other three forces. Some theories, notably string theory, seek both QG and GUT within one framework, unifying all four fundamental interactions along with mass generation within a theory of everything.

Space science has led to many amazing developments in technology. Scientists have studied combustion in microgravity in order to design more efficient jet engines. We have all benefited from technology that was designed for use in space. Microchips found in digital watches, computers and mobile phones were first developed so that lots of equipment could fit into a small spacecraft. Many household items have come about because of space technology, including air-tight cans and tin foil. Technologies such as solar power and keyhole surgery have also advanced largely due to the space programme.

The study of space has taken ideas that began outside our corner of the universe and adapted them to benefit our own planet Earth in amazing ways. Here are some out of this world space exploration technologies and innovations that came from studying space but have changed our lives here on Earth. These contributions from space may have had out-of-this-world origins, but they ended up advancing technology right here on our own planet.

Digital photography technology was developed at NASA’s Jet Propulsion Laboratory in the 1960s as a way to capture images from long range telescopes. In the 1990s, the technology was miniaturized to enable spacecraft to carry it on board, which led to the ability to make cameras on smartphones inexpensively. The first wireless headsets were created so Neil Armstrong and other astronauts could communicate with NASA from the moon, and technology has continued to evolve into today’s Bluetooth technology and other wireless communication devices.

This easy-to-use device for taking someone’s temperature in seconds started out as a way for space scientists to determine the temperature of distant planets and stars using infrared technology. Now, it enables medical professionals and parents to easily take the temperature of patients, their kids, or anyone in need of medical evaluation. Originally developed by NASA to use aboard spacecraft, the technology for purifying water supplies is now commonly used in water treatment plants. It keeps contaminants and pollutants from getting into Earth’s water distribution systems and causing widespread disease outbreaks.

Solar energy was responsible for two-thirds of the new energy capacity generated worldwide in 2017. Solar energy technology came from space scientists who wanted to find ways to generate energy in space without using fossil fuels, which are heavy to carry and eventually run out. Space scientists developed temper memory foam to make space capsule seats more comfortable for long flights. However, it is now used in mattresses, pillows, shoes, and prosthetic limbs to provide comfort and cushioning for those with chronic pain or who spend long hours on their feet. Equipment used to track the heart rates of astronauts while they were in space or walking on the moon was modified to provide a way to track athletes’ and exercisers’ heart rates and make sure they are within healthy limits.

Current technology, which can be used on tumors resistant to other methods, was developed by NASA to grow food in space and perform other tasks. NASA asked Black & Decker to create Dustbusters in 1979 as a handheld device to suck up moon rocks and dust to be studied. The company then applied the technology to portable vacuum cleaners and a new era of cleaning tools was born.

The type of insulation used in most newly built homes today was developed as a way to protect its equipment and systems from extreme temperatures in space. The first portable computers were developed for use during space travel and were later adapted for commercial use by manufacturers. Now, they are the majority of the home computer market.

It was Isaac newton who discovered that all falling bodies accelerate at the same rate. His second law of motion states that the greater an object’s mass, the greater the force required accelerating it. A bowling ball weighing 7kg is pulled to Earth by a gravitational force 100 times as strong as a 70g tennis ball. However, because the bowling ball’s mass is 100 times greater to start with, the acceleration of the two balls will be exactly the same.

Most of the time, people ask this question with the idea of a Newtonian “feather vs. bowling ball” concept in mind. Based on those terms, the typical answer is correct: two objects will fall at the same speed in a vacuum, and air resistance can appear to make an object fall slower. However, there is a surprising, but more complicated nuance to this problem.

Every action has an equal and opposite reaction. This means that, just as the Earth is exerting a gravitational force on the objects, the objects are exerting a gravitational force on the Earth. Just as much as the objects fall onto the Earth, the Earth falls onto the objects as well. It’s just the fact that the Earth is so much larger and more massive that we default to viewing things from the first perspective and not the latter. Nevertheless, the gravitational force exerted on the Earth by the objects cannot be ignored. Gravitational force is determined by the Universal Gravitation law:

Where m and M are the two masses involved in the interaction. If we do two separate calculations, one for the mass of the lesser object, and one for the mass of the greater object, we can see that there will actually be a larger gravitational force involved with the more massive object.

This is where most people would interject that, well, yes, the larger mass needs a larger force in order to achieve the same acceleration. But reverse the frame of reference; now let’s consider this from the point of view of the objects doing the pulling, instead of the Earth. Now we can see that the force exerted by the larger mass is doing more.

Working in Space allows scientists to explore how different things are affected by gravity. The European Space Agency’s Spacelab was designed with two pressurized laboratories where microgravity experiments could be carried out. Special racks held hundreds of different kinds of cells and organisms including bacteria, lentil seedlings and shrimp eggs. Tests were run on these organisms, and on human beings, to determine whether they behaved differently in space.

Scientific research on the International Space Station is a collection of experiments that require one or more of the unusual conditions present in low Earth orbit. The primary fields of research include human research, space medicine, life science, physical sciences astronomy, and meteorology. The 2005 NASA Authorization Act designated the American segment of the International Space Station as a national laboratory with the goal of increasing the use of the ISS by other federal agencies and the private sector.

Research on the ISS improves knowledge about the effects of long-term space exposure on the human body. Subjects currently under study include muscle atrophy, bone loss, and fluid shift. The data will be used to determine whether space colonisation and lengthy human spaceflight are feasible. As of 2006, data on bone loss and muscular atrophy suggest that there would be a significant risk of fractures and movement problems if astronauts landed on a planet after a lengthy interplanetary cruise (such as the six-month journey time required to fly to Mars). Large scale medical studies are conducted aboard the ISS via the National Space Biomedical Research Institute (NSBRI). Prominent among these is the Advanced Diagnostic Ultrasound in Microgravity study in which astronauts (including former ISS Commanders Leroy Chiao and Gennady Padalka) perform ultrasound scans under the guidance of remote experts. The study considers the diagnosis and treatment of medical conditions in space. Usually, there is no physician on board the ISS, and diagnosis of medical conditions is a challenge. It is anticipated that remotely guided ultrasound scans will have application on Earth in emergency and rural care situations where access to a trained physician is difficult.

Researchers are investigating the effect of the station’s near-weightless environment on the evolution, development, growth and internal processes of plants and animals. In response to some of this data, NASA wants to investigate Microgravity’s effects on the growth of three-dimensional, human-like tissues, and the unusual protein crystals that can be formed in space.

The investigation of the physics of fluids in microgravity will allow researchers to model the behaviour of fluids better. Because fluids can be almost completely combined in microgravity, physicists investigate fluids that do not mix well on Earth. In addition, an examination of reactions that are slowed by low gravity and temperatures will give scientists a deeper understanding of superconductivity.

The study of materials science is an important ISS research activity, with the objective of reaping economic benefits through the improvement of techniques used on the ground. Other areas of interest include the effect of the low gravity environment on combustion, through the study of the efficiency of burning and control of emissions and pollutants. These findings may improve our knowledge about energy production, and lead to economic and environmental benefits. Future plans are for the researchers aboard the ISS to examine aerosols, ozone, water vapour, and oxides in Earth’s atmosphere, as well as cosmic rays, cosmic dust, antimatter, and dark matter in the universe.

Space stations typically orbit between 192 and 576km (120 and 360 miles) above the Earth’s surface. The Earth’s gravitational pull is still quite strong, even at this altitude. If you were standing on Earth and dropped a ball, it would fall to the ground. If an astronaut on a space station dropped a ball, it would fall, too. However, the ball would appear to float in mid-air because it, the astronaut and the space station are all falling at the same speed. They are not falling towards the Earth, but around it. This condition is called microgravity.

Microgravity is the condition in which people or objects appear to be weightless. The effects of microgravity can be seen when astronauts and objects float in space. Microgravity can be experienced in other ways, as well. “Micro-” means “very small,” so microgravity refers to the condition where gravity seems to be very small. In microgravity, astronauts can float in their spacecraft – or outside, on a spacewalk. Heavy objects move around easily. For example, astronauts can move equipment weighing hundreds of pounds with their fingertips. Microgravity is sometimes called “zero gravity,” but this is misleading.

Gravity causes every object to pull every other object toward it. Some people think that there is no gravity in space. In fact, a small amount of gravity can be found everywhere in space. Gravity is what holds the moon in orbit around Earth. Gravity causes Earth to orbit the sun. It keeps the sun in place in the Milky Way galaxy. Gravity, however, does become weaker with distance. It is possible for a spacecraft to go far enough from Earth that a person inside would feel very little gravity. But this is not why things float on a spacecraft in orbit. The International Space Station orbits Earth at an altitude between 200 and 250 miles. At that altitude, Earth’s gravity is about 90 percent of what it is on the planet’s surface. In other words, if a person who weighed 100 pounds on Earth’s surface could climb a ladder all the way to the space station, that person would weigh 90 pounds at the top of the ladder.

If 90 percent of Earth’s gravity reaches the space station, then why do astronauts float there? The answer is because they are in free fall. In a vacuum, gravity causes all objects to fall at the same rate. The mass of the object does not matter. If a person drops a hammer and a feather, air will make the feather fall more slowly. But if there were no air, they would fall at the same acceleration. Some amusement parks have free-fall rides, in which a cabin is dropped along a tall tower. If a person let go of an object at the beginning of the fall, the person and the object would fall at the same acceleration. Because of that, the object would appear to float in front of the person. That is what happens in a spacecraft. The spacecraft, its crew and any objects aboard are all falling toward but around Earth. Since they are all falling together, the crew and objects appear to float when compared with the spacecraft.

Space stations have given scientists a unique laboratory that can be found nowhere on Earth —one that is unaffected by gravity. Gravity influences everything on Earth, from the way that the human body works to the growth of crystals used in semiconductors for computers. In orbit, however, a space station’s speed cancels out the Earth’s gravitational pull, so scientists can carry out experiments in weightless conditions.

Space Science is the study and research of issues specifically related to space flight/ travel and space exploration. It comprises of interdisciplinary fields e.g. Stellar, Solar, Galactic and Extragalactic astronomy, Planetary Science and Physical Cosmology, Astrobiology, Astrochemistry, Astrophysics, Space plasma physics, Orbital mechanics/ Astrodynamics, Atmospheric/ Environmental Science, Satellite and Space Communications, Aerospace engineering, Control engineering, Space environment and Space medicine.

Rapidly growing subjects of Space Science in the present era of information technology are in process of evolution from the state of infancy to the advanced levels at academic and research institutions. The significant subjects falling under the umbrella of Space Science comprise Remote Sensing, Satellite Applications, Space Physics, Astrodynamics, Atmospheric Science etc. The courses offered in the department are the main building blocks of Space Science. Emphasis has also been given to research and applications oriented areas such as Flight Dynamics and Control, Space Mission Design and Analysis, Space Data Processing and Geoinformatics. The Space Science uses new space-age technologies like satellite positioning, space data visualizations, analysis tools and space data interpretation to greatly advance scientific understanding of Earth and its systems. With the launch of Earth resources satellites such as micro & Nano satellites in Low Earth Orbit and Communication Satellites in Geostationary orbits around the Earth, the last decade has witnessed a wide spectrum of applications in diverse fields subject to the need and quality of imagery datasets acquired from the Earth orbiting satellites. The advances in computing technology & techniques have also contributed a lot in the development of more sophisticated than ever sensors capable of observing the Earth with specialized and dedicated on-board sensors with the help of satellite constellations.

The Space Science department at IST is a truly multidisciplinary department within a multidisciplinary university. As society looks towards the future, we continue the pursuit of further understanding the Earth system and beyond with our focus on Space Communications, Remote Sensing, Astrodynamics, Atmospheric Science, Meteorology and Earth Sciences. The department also conducts public awareness programs like Sky-watch/ Star-gazing shows and World Space Week (UN) for scientific outreach.