Podcast Summary
Expert Perspective on 'Gravity': Though 'Gravity' contains some inaccuracies, focusing on the scientific facts presented and acknowledging creative liberties can make for an engaging educational experience.
While the survival story in the movie "Gravity" may seem simple at first, with only Sandra Bullock and George Clooney in space, the film is anything but boring due to the constant action and danger. Neil DeGrasse Tyson, who is an astrophysicist in real life, found the concept underwhelming until they brought in astronaut Mike Massimino, who has actually been in space. Massimino shared his experiences and helped answer scientific questions about the film, acknowledging that while there were some inaccuracies, the overall grounding of the movie in science was sufficient. High school biology teacher Allison, who called in, asked Neil about addressing the inaccuracies with students, and Neil suggested focusing on the correct elements while acknowledging that some liberties are often taken in movies.
Accurately portraying space travel in 'Gravity': 'Gravity' realistically depicted space using astronaut tools, authentic locations, and captured the mood and danger of space travel, though some aspects like jet packs were dramatized.
"Gravity," a movie about space travel, accurately portrayed the look and feel of space, using the same tools and suits as real astronauts. Sandra Bullock's character even repaired the Hubble Telescope with similar tools. The movie captured the mood and danger of space travel effectively. However, some aspects, like the ease of moving around in space with jet packs, were taken liberties with for dramatic effect. The inclusion of the retired Space Shuttle and the International Space Station added to the authenticity, despite requiring some creative license. While watching the movie, a real astronaut experienced some anxiety, recognizing the dangers portrayed. Overall, the movie's accurate representation of space and space travel was impressive.
The Misconception of Weightlessness in Space: Astronauts are in a constant state of falling towards Earth due to gravity, contrary to the popular belief of weightlessness in space.
While the movie "Gravity" may not have accurately portrayed the scientific aspects of space travel, such as the presence of gravity and the experience of weightlessness, the fundamental concept of free fall and its relationship to gravity is an essential part of space exploration. Contrary to popular belief, astronauts are not weightless in space; instead, they are in a constant state of falling towards Earth due to Earth's gravitational pull. This misconception was addressed by Astro Mike Massimino during a StarTalk Radio episode, where he clarified the physics behind free fall and gravity for listeners. The episode also touched upon the importance of accurate scientific representation in movies and the potential impact of such misrepresentations on public perception.
Experience Weightlessness: Orbits and Amusement Park Rides: Orbits create weightlessness, similar to amusement park rides, and living in such an environment could lead to more efficient use of space
An orbit is a continuously falling object that never hits the ground due to the curvature of the planet. This results in a weightless state for objects and people in space. This weightless feeling can be experienced in everyday life through certain situations like riding an amusement park ride or feeling the sensation of weightlessness in a neutrally buoyant environment, such as a swimming pool. When in a weightless state, people may experience a sensation similar to nausea, but they quickly adjust after a day or so. If we could live in a weightless environment, we could use our living spaces more efficiently, allowing us to access high ceilings and float around our homes. To illustrate this concept, try filling a tall cup with water and poking two holes in it, one at the bottom and one at the top. The water will spout out farther from the upper hole due to less pressure, demonstrating the principle of weightlessness.
Misconception of astronauts falling in space: Astronauts don't constantly fall towards Earth at 17,500 mph. They fall towards Earth due to the Earth's curvature and the horizontal speed acquired during launch.
The astronauts in space are not constantly falling at 17,500 miles per hour as it may appear from our perspective on Earth. Instead, they are falling towards the Earth at a rate determined by the Earth's curved surface and the horizontal speed they acquire during launch. This misconception arises because most of the energy from the rocket engines is used to give the spacecraft horizontal speed rather than lifting it up into space. The scene in the movie Gravity where Sandra Bullock uses a fire extinguisher as a makeshift propulsion device to maneuver in space is largely a Hollywood effect, as the nozzle on a fire extinguisher is not capable of generating the necessary thrust for such maneuvers.
Newton's Laws Affect Astronauts in Space: Newton's laws cause equal and opposite reactions in space, impacting astronauts' movements and cognitive abilities
In a weightless environment like space, any change in mass or directional force will cause an equal and opposite reaction on the individual, as per Newton's law of action and reaction. This means that if an astronaut propels any part of their body or an object, they will recoil and potentially rotate if not aimed correctly. For instance, using a fire extinguisher as a propulsion device could lead to unintended rotation. Astronauts, like Mike Massimino, have experience with controlled propulsion systems in space, such as jetpacks, to maneuver around. The weightlessness of space can also affect cognitive capabilities, as the brain struggles to determine up from down due to the absence of gravity, which can impact balance and orientation.
Adjusting to Space: Inner Ear and Body Challenges: Astronauts face disorientation and physical changes when going to space due to inner ear confusion and body fluid redistribution, but they eventually adapt, allowing them to function effectively despite initial difficulties.
When humans go to space, their inner ear and body have to adjust to new conditions. The inner ear, which helps us maintain balance based on gravity, can be confusing when we're upside down or weightless. Our brains initially interpret the environment as having rotated, leading to disorientation. Additionally, our bodies produce more urine due to the redistribution of fluids, and some astronauts experience nausea. Despite these challenges, the brain and body eventually adapt, allowing astronauts to function effectively in space. However, the process can take a few days, and astronauts must take precautions, such as drinking enough water and managing waste, to stay healthy. The disorientation and physical changes can make simple tasks, like moving around or accessing other spacecraft, more difficult, but with time and adjustments, astronauts can overcome these challenges.
Astronauts face unique challenges during spacewalks: Despite advanced equipment, astronauts' gloves are the weakest part of their suits, requiring flexibility but susceptible to tears. Airlock doors open from the inside, necessitating pressure equalization before accessing sealed spaces.
Space exploration requires careful attention to detail, even with the most advanced equipment. During spacewalks, astronauts face unique challenges, such as weak points in their gloves, which need to be flexible but can tear easily. These gloves are part of a multi-layered suit, including Kevlar, for protection against debris and pressure leaks. However, the gloves do not have Kevlar layers, making them the weakest part of the suit. Airlock doors open from the inside due to pressure, making it impossible to access sealed spaces from the outside without equalizing the pressure first. These precautions are necessary to ensure the safety of astronauts in the harsh environment of space.
Misconception of lighter space doors due to gravity absence: Space doors are heavy to open due to significant internal pressure caused by air pushing from all directions, similar to suction cups on Earth.
The concept of a door in space being able to be opened with less pressure due to the absence of gravity is a misconception. The pressure inside a spacecraft or space station is significant due to the air pushing from all directions, making the doors heavy to open. This is similar to how suction cups work, where the atmosphere pushes down on them, creating a force that needs to be overcome to lift them. Additionally, most items in space are fireproof, and the behavior of fire in zero gravity is not fully understood as there haven't been extensive real-life experiments.
Fires in Space vs Earth: Fires in space self-extinguish due to lack of oxygen, while astronauts have varying shapes and sizes with high cost to reach orbit
Fires in space behave differently than on Earth due to the lack of oxygen and gravity. A candle on Earth will continue to burn because of the continuous flow of oxygen and the convection caused by gravity. However, in space, there is no fresh oxygen to replace what's used, making it impossible for a fire to sustain itself. Fires in space are like our debt ceiling on Earth - a potential disaster that no one wants to explore. As for astronauts, they may look good on screen, but in reality, they come in all shapes and sizes. And, just like on Earth, an astronaut's weight doesn't affect the Earth's gravity when they're not there. But it does cost a pretty penny to get them and their supplies into orbit. So, in summary, fires in space are self-extinguishing due to the lack of oxygen, and astronauts come in all shapes and sizes, with a hefty price tag for getting them into space.
Exploring Hypothetical Scenarios in Space: Quick thinking, problem-solving, and adaptability are crucial skills for space explorers, as they face unfamiliar environments and must make tough decisions.
Space exploration involves making tough decisions and adapting to unfamiliar environments. During a discussion, Mike and Chuck explored various hypothetical scenarios. One topic was weight in space, with Mike admitting he weighed more than his stated terrestrial weight. Another topic was the existence of a suicide pill in space, to which both agreed they would rather survive as long as possible. They also discussed the possibility of launching a satellite with the ability to change orbital altitudes and re-entering Earth's atmosphere, requiring fuel. Acidosis, a term used in the conversation, was revealed to be a term unfamiliar to some, and astronauts were said to focus on breathing lightly to conserve oxygen. Lastly, Mike inquired about the ability to look at the sun for extended periods in space, which was explained to be different from on Earth due to the lack of atmospheric protection. Overall, the conversation highlighted the importance of quick thinking, problem-solving, and adaptability in space exploration.
The Importance of Protective Gear in Spacewalks: Astronauts wear visors during spacewalks to shield themselves from the sun's brightness, emphasizing technology's role in enabling safe exploration of space.
Key takeaway from this episode of StarTalk Radio's Cosmic Queries is the importance of protective gear, specifically visors, during spacewalks. Astronaut Mike Massimino shared his personal experience from the movie Gravity and in real life, emphasizing the significance of having a visor to shield oneself from the brightest thing imaginable in space - the sun. This discussion highlights the crucial role of technology and equipment in enabling astronauts to perform their duties safely and effectively in the harsh conditions of space. So the next time you put on your sunglasses, remember the astronauts and their visors, and keep looking up to the wonders of the universe. This episode was brought to you in part by a grant from the National Science Foundation, and as always, we encourage you to keep exploring and learning about the cosmos. Thank you, Chuck Nice, for hosting, and a special thanks to Astro Mike for joining us and sharing his insights. Until next time, I'm Neil DeGrasse Tyson, your personal astrophysicist. Keep looking up!
