Using footage from the International Space Station (courtesy of NASA’s Johnson Space Center), National Geographic filmmaker Fede Castro has created one of the most breathtaking time-lapse videos of Earth from space.
The video is just over four minutes, and features the world’s major cities, as well as the aurora borealis (Northern Lights) and a few massive thunderstorms, among other things.
Take a trip around the world in just minutes in National Geographic’s video “Nuestra Tierra—Our Earth”:
Today, we think of Mars as having a cold, dry, and desolate environment (because it does).
But that was not always the case. Four billion years ago, while our Sun was still in its infancy, Mars was covered with water.
Back then, it had a much thicker atmosphere, which kept the planet warm enough for water to exist in its liquid form. Some estimates say that at one point, up to 1640 ft (about half a kilometer) of water covered the whole planet.
Okay so everyone hopefully understands that you can’t just simply survive in the openness of outer space. That’s why astronauts are required to wear sophisticated suits to keep them safe.
There are many reasons why outer space is not naturally habitable for humans, the lack of air and extreme temperatures being just the tip of the iceberg.
But with a proper suit built to provide protection and breathable air, one can spend limited amounts of time in outer space.
According to Space.com four of the most hostile elements in space are:
1. The Empty Vacuum – The vacuum force, caused by a lack of air in space, can be large and significant. If instruments are unsealed they can break apart. If an astronaut has a suit leak or damage it will be exposed and compromised.
2. Extreme Temperature/Temperature Variation – According to Space.com,
“If an astronaut’s back is facing the sun and the front is not, the temperature difference can be as much as 275°F”
That is an extreme temperature difference for just the direction that you are facing. Astronaut suits must have heavily shielded face plates to protect astronauts from the sun, as well as the capability to handle both temperature exteremes (hot and cold).
Universetoday.com did a great piece called “How Cold is Space” that helped answer a few questions on how extreme the temperatures get in outer space. According to them, the International Space Station…
“…under constant sunlight can get as hot as 260 degrees Celsius (500 F). This is dangerous to astronauts who have to work outside the station. If they need to handle bare metal, they wrap it in special coatings or blankets to protect themselves. And yet, in the shade, an object will cool down to below -100 degrees Celsius (-148 F).”
3. Meteorite Impacts – Although colliding with other objects in space is rare, it is entirely possible and a legit threat. If you are within the orbit of a planet, where much of this debris gets captured, the threat is even higher.
The amount of satellites in space is growing by the day, steadily increasing the amount of “space junk” within Earth’s orbit. Aside from that, small meteorites zoom past the outskirts of space and into our ozone everyday.
4. Radiation Damage – This is one of the most significant threats in space, especially to equipment. There are several sources and forms of radiation in space which can all be harmful to human health in a large enough dose.
The main issue, however, is that this radiation can damage the finely-tuned instrumentation used by astronauts to do experiments in space. The radiation can alter and destroy data, and eventually renders almost all instruments in space useless.
Roger Shawyer is one of the most persistent and driven individuals in the world.
For years, he has been working on a new type of propulsion engine that could theoretically run forever without needing any fuel. He calls his device the EmDrive.
The engine works by bouncing around microwave radiation in a small space to produce thrust, rather than burning a propellant fuel. The microwaves are produced by solar power which is generated from panels on the outside of the engine.
When he first began proposing the idea for a quantum vacuum plasma thruster, Shawyer was laughed at. Most scientists he talked to told him the idea was ludicrous, saying that (among other issues) it defied the theory of conservation of momentum.
Only a group of Chinese scientists was willing to actually try out the idea. In 2009, they built a model of Shawyer’s engine that actually worked, producing enough thrust to power a small satellite.
Even then, many people weren’t convinced. But recently, American scientist Guido Fetta and a team at NASA Eagleworks (NASA’s experimental technologies division) recreated the engine for themselves, and found that the design actually does in fact work.
In a statement about their findings, the NASA research team said:
“Test results indicate that the RF resonant cavity thruster design, which is unique as an electric propulsion device, is producing a force that is not attributable to any classical electromagnetic phenomenon and therefore is potentially demonstrating an interaction with the quantum vacuum virtual plasma.”
The whole mystery behind the engine stems from the difference between how physics operates on a large scale in our every day world, and how it operates on the microscopic, quantum level (ie. quantum physics).
When we observe molecules in their most basic form, they often don’t follow the same rules of physics that govern our visible world.
For example, if you throw a tennis ball off of a wall, you wouldn’t expect it to speed up after hitting the wall- its acceleration is totally dependent on how much force you release the ball with.
But on the quantum level, things change. Shawyer describes the principles of how the engine works here, but the wording is a bit overly scientific if you’re not an engineer, so I’ll try to break it down as best I can.
Basically, the microwave particles that the EmDrive uses can travel extremely fast (up to almost the speed of light). Because of this high velocity, the particles exert a force (albeit a very, very small one) on the reflective inner walls of the engine.
So, each reflector has a different velocity at its surface, depending on how many radiation molecules are hitting it and how fast they’re moving. Imagine someone throwing marbles at the surface of a number of drums- the drum being hit by the largest amount of fast-moving marbles is going to be vibrating the most.
The radiation molecules have virtually no mass. Because of this, their momentum can actually be increased by bouncing them from a reflector with a lower surface velocity to one with a higher surface velocity. This added momentum comes from the difference in force between the two surfaces.
By taking advantage of this principle and carefully designing the inner geometry of the thruster, Shawyer was able to create a compartment that perfectly bounced the microwave radiation between reflectors, steadily increasing its momentum until it gets released out of the end as thrust.
And since the microwaves are generated using solar panels, the engine could theoretically work forever, or at least until its hardware fails.
There still needs to be much more extensive testing to prove that the engine can be replicated and utilized on a larger scale, but the basic concept has been demonstrated twice now.
The lesson: never stop pursuing your dreams. The people who make the biggest impacts on our society are usually people who have been called crazy more than a handful of times throughout their lives.
So, to you Roger Shawyer: thanks for being a stubborn dreamer. I hope your engine plays a big role in revolutionizing this era of space exloration and discovery!
NASA’s Opportunity rover landed on the surface of Mars in January of 2004. As of Sunday (July 26), the Opportunity rover had driven a total distance of 25 miles (40 kilometers).
Opportunity took the top spot in total off-world distance traveled by surpassing Russia’s Lunokhod 2 lunar rover, which traveled a total distance of 39 kilometers across the surface of the moon between January and May of 1973.
The Russian rover helped to bring about a golden age of space exploration in the 70s. As a sign of respect, the Opportunity rover’s operators decided to commemorate the Russian rover by naming one of the first craters they encountered after it.
The craziest part of this record is that the Opportunity rover was only expected to travel a short distance when it was first sent to Mars in 2004. Here’s John Callas, who manages the Mars Exploration Project at NASA’s Jet-Propulsion Laboratory (JPL) in California:
“This is so remarkable considering Opportunity was intended to drive about one kilometer and was never designed for distance. But what is really important is not how many miles the rover has racked up, but how much exploration and discovery we have accomplished over that distance.”
The Opportunity rover is collecting data on Mars as part of a long-term plan for a manned mission to the planet around the year 2030.
The infographic below compares the distances driven by different rovers throughout the years. Click to enlarge (courtesy of NASA/JPL-Caltech):
But the mood has become a bit more somber with the end of the Cup and the resurgence of the conflict in the Middle East.
In a blog post he wrote for the European Space Agency’s website, Gerst gave insight into the astronauts’ perspective on the Israeli-Palestinian conflict. His introduction is very powerful:
“Some things that on Earth we see in the news every day and thus almost tend to accept as a ‘given,’ appear very different from our perspective. We do not see any borders from space.
We just see a unique planet with a thin, fragile atmosphere, suspended in a vast and hostile darkness. From up here it is crystal clear that on Earth we are one humanity, we eventually all share the same fate.
What came to my mind at the time of this photo was, if we ever will be visited by another species from somewhere in the universe, how would we explain to them what they might see as the very first thing when they look at our planet?”
How would we explain to them the way we humans treat not only each other but also our fragile blue planet, the only home we have? I do not have an answer for that.”
NASA is confident that underneath Jupiter’s moon Europa there could be more water than in our oceans here on Earth. So naturally, Europa has attracted a lot of attention, encouraging the curious to ask, “Could there be life on Europa?”.
Currently, NASA is aiming to send a new mission to Europa by 2025. The White House’s 2015 federal budget allocates $15 million towards making this Europa mission a reality.
Europa has recently become one of NASA’s main focuses because, out of all the other planetary bodies in our solar system, it has arguably the greatest chance of harboring life.
“Every 10 years, the U.S. National Research Council, a nonprofit organization that advises the government, issues a report that recommends a planetary exploration strategy for NASA and the National Science Foundation. The current report (which covers 2013 to 2022) ranks an exploration of Europa among the highest priority missions. According to the report, the future mission should focus on taking a closer look at the ocean that scientists suspect lies below the surface; characterizing its icy crust and looking for any subsurface liquid water; determining the surface composition and chemistry; examining surface features and identifying landing areas for future missions; and understanding the purpose of its magnetosphere — the magnetic field surrounding the celestial body. NASA officials said the instrument proposals should focus on at least one of these exploration goals. The announcement calls for instruments designed for a spacecraft that will orbit Europa or complete several flybys, since astronomers do not yet have enough data to pinpoint safe landing sites on the icy moon.”
The video below describes Europa in more detail.
NASA hopes that by providing monetary incentives to private parties, they will encourage competition and innovation, leading to affordable development processes for the instruments necessary for new missions like the upcoming one to Europa.
Two of the main challenges for teams developing instruments are overcoming Jupiter’s high levels of radiation and making sure that no organic material from Earth (like microorganisms, for example) is introduced to Europa’s potentially habitable surface.
The competition ends in April 2015. NASA will select the top 20 proposals, rewarding $25 million to each of the selected teams to further advance their designs for their instruments. NASA will also select eight winners whose instruments will be developed and actually used in NASA’s mission to Europa.
This competition is included in NASA’s budget to get to Europa, according to Space.com…
“NASA is in the process of designing a mission that will cost less than $1 billion and will still meet as many of the exploration goals as possible.”
Check out NASA’s full guidelines for Europa mission science instrument ideas here.
You can also learn more about how Europa works in this infographic from Space.com (click to enlarge):