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Evacuate Earth Facts

CGI IMAGE: A Neutron star.

A Neutron star. (View larger version)

Photograph by National Geographic Channels/ Nate Evans

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  • Our solar system orbits around the galaxy once every 210 million years, which means since the beginning of life it has gone around the solar system only 20 times!

  • A neutron star is incredible dense and can have the mass of two or three times the sun, but only have a diameter of 10 to 20 miles.

  • Because of the neutron star’s incredible density, it’s gravitational pull gets much stronger the closer you get to it. This means that a neutron star has a deep gravity well and that could pull objects apart at they get closer to it.

  • A neutron star is so dense and hot that if the Earth came close to one, it would rip the Earth apart and either suck it into the neutron star or the matter would orbit the star and become a ring system.

  • An exo-planet is a planet that orbits a star that isn’t our sun. Today, we know of hundreds of exo-planets.

  • Kepler is a telescope that is tasked with finding exo-planets, planets orbiting other stars in hopes of finding a planet that can sustain life like Earth.

  • Kepler studies the light of a star and looks for a slight drop in the brightness. If this slight drop is repeated, we can determine that there is a planet passing in front of the star and Kepler is seeing the planet’s shadow.

  • The Kepler Space telescope has found planets the size of Earth, but that doesn’t mean that they are habitable. For example, Earth and Venus are the same size, but Venus is hot enough to melt lead on its surface. So we’re looking for more than just the right size. Scientists are also looking to see if the planet is in the Goldilocks Zone, the distance from the star where the temperature on the planet would be just right for liquid water. They are also looking for gases like oxygen that would indicate signs of life.

  • We can identify gases on other planets like Mars, Venus, or Jupiter by using a technique call spectrometry. For exo-planets that are far away we need a very large telescope. In fact, we have already looked at 30 Earth-like planets with the Hubble Space telescope and Spitzer Space Telescope, but they have turned out to be large hot planets not suitable for life.

  • Gravity is one of the major concerns for long term space travel, even taking the 18 month trip to Mars has scientists concerned about astronauts’ health. Without gravity the human body losses muscles mass  and the bones suffer from calcium decay. Fortunately, there is a way to create gravity in space –if you have a cylinder that is slowly rotating, the centripetal force on your body is enough to simulate gravity.

  • The planet Venus has no magnetic field and if we were to live on it we’d be exposed to much more radiation than we are here on Earth.
11 comments
John Orhan
John Orhan

To answer the gentleman's previous question, we cannot deflect its trajectory, it weighs far too much (up to twice the weight of the sun in spite of its small 15km diameter). Just one cubic cm of its 'stuff' (neutronium) would weigh as much as a mountain (100billion tons or more). Its gravity would be up to twice that of the sun. If it magically entered our solar system, it would fall into a decaying orbit around our sun, stripping gas from the suns surface before eventually merging with it and possibly collapsing further to a smaller diameter (3km?). Earth and all the other planets would be basically turned into energy as their atoms are tripped apart from the immense gravity. There wouldn't be enough energy or mass on earth with all the other planets combined to even slow it down. Any matter falling onto the neutron stars surface would be turned into the same degenerate matter its made of letting off gamma ray bursts as it went E.G: If you dropped a pen onto the stars surface, it would impact with the force of a hydrogen bomb at ridiculous speeds approaching light speed.


BTW, any attempt to leave the solar system would fail, the star would destroy everything with its radiation. We would all die.


Cheers,

John


John Orhan
John Orhan

Still I guess that begs the bigger question, what could be energetic enough to move a neutron star?! We would have t be incredibly unlucky. Not likely to happen.

John Orhan
John Orhan

I guess luckily for us, since the sun is about 99.7% of all the solar systems mass, it would attract the Neutron star towards it rather than earth. Still I guess that as it passed earth on its way into orbit around the sun, earth (and the other planets) would b spagettified in milliseconds.


Regards,

John

John O'Halloran
John O'Halloran

Some things to consider one the scale of this project. A majority of the GDP of the world would be funneled into this project in one form or another. The current global GDP is likely in the neighborhood of $50 trillion. With that type of budget I think we might be able to move "heaven and Earth".


The United Nations will likely morph into a world government. This will be forced by the realization that if we do not learn to live together we will definitely all die alone.


The crew will be trained from birth. If the time line is at least 40 years this will mean for at least 10 years they will be developing the training with every child on the planet as a test subject. By the launch date most of the people alive at that time will have been through a training program that would have conditioned to calmly accept the fact if they are not chose for the journey.


With the resource available for this most likely a much larger number of people will be part of the crew and many fewer will be left behind as birth control will have been strongly encouraged for 40 years. Even without the encouragement many will not want to have children with the prospect of them either living out their lives in a space ship or watching the last days of Earth from the front row.

John O'Halloran
John O'Halloran

For the question of changing the trajectory we are talking about a start. Even as a neutron start in has many times the mass of Jupiter. It would be easier to convert the moon into a ship to fly to a new home than it would be to change a neutron stars trajectory in any way. In fact this may be a more reasonable idea then the one presented in the video.

For the person who said they would want to stay on Earth, what they missed in this was that if this did happen as they described it no one alive today would be taking the trip. The scale of the voyage would be 40 or more years in the making, every adult alive today would be too old to make the trip. It is unlikely that any child alive today would be deemed fit to make the trip. It is likely the grandchildren of the kid today would be the ones to make the trip.

The drive the think is most likely to take us to a different star is silly. I would compare it to the Vern idea of sending people to the Moon by cannon. The idea that we could not come up with a better idea with all the world resources and people looking for one is down right stupid. The more likely engine will be the same one that brings the neutron star, plasma drive. It may user anti-matter to boost the power but the main source of impulse will be a stream of plasma.

Mario Donato
Mario Donato

why cant they just change its trajectory

Michael Super
Michael Super

Unfortunately, whether or not this scenario were to come about, the earth will, at some point in time, be unable to sustain life as we know it. To enable the survival of the species, we MUST begin to plan for the evacuation now, not when a threat like this presents itself. We must immediately start planning to build a ship capable of carrying 25,000 or more people with the DNA diversity they mention here. This way, all of the people on board will be not only volunteers, but there would not be the worldwide turmoil that will inevitably be created by the existence of a planet killing threat. This turmoil would also include of course, the 99.999 percent of the people on the planet that will refuse to participate financially or in any other way towards the building of this ark if they won't be chosen to go. Also, if we only need to build a ship capable of carrying this much smaller number of people, we can build more than one and go in different directions. By the time these ships are built, we almost surely will have identified numerous other worlds that we believe will sustain our life forms. If we really want to preserve the species, we cannot put all of our eggs in one basket, or in this case on one world. These different ships would also be able to communicate with each other so that if you of them finds a habitable world they would be able to know where they all are in case one or more the destination planets turns out to be uninhabitable once they get there.

Neil Weisthal
Neil Weisthal

Fantastic show.  I would take my chances staying on a doomed Earth though rather than going to an unknown new planet.  Just too many risks with that.  Sort of the Devil you know thing

Thomas Franckowiak
Thomas Franckowiak

I watched Evacuation Earth today. It was a fascinating program except the timeline of events of the earth´s evacuation seemed to be tardy. Evacuees would be wise to evacuate well before the neutron star entered the solar system essentially because the construction of a colossal mother ship capable of transporting 250,000 people would require vast resources. So if the neutron star had already neared the solar system, already weakening the earth´s atmosphere, distorting its orbit, affecting its weather, and causing increased radiation to threaten life, there would already be too much chaos on earth and vastly reduce resources to coordinate and to complete mother ship´s construction. 

Moreover, the people who would be selected to board the ship would be probably 50,000 to 100,000 rather than 250,000 because much room aboard the ship to carry spare parts and construction materials and machinery would be necessary. Most of the people aboard the ship would either be scientists, engineers, or construction technicians who could both keep the ship going for its 80 to 100 year voyage and be able to build a habitation on the exoplanet. If the explanet were not completely friendly or conducive to life, they would need to be able to construct a habitation with an artificial environment. But what if the exoplanet could not sustain life at all or was already inhabited by intelligent and advanced civilizations? What would be plan B? How would the crew of the ship locate another planet and continue its time in space?

Thomas Franckowiak
Thomas Franckowiak

I watched Evacuation Earth today. It was a fascinating program except the timeline of events of the earth´s evacuation seemed to be tardy. Evacuees would be wise to evacuate well before the neutron star entered the solar system essentially because the construction of a colossal mother ship capable of transporting 250,000 people would require vast resources. So if the neutron star had already neared the solar system, already weakening the earth´s atmosphere, distorting its orbit, affecting its weather, and causing increased radiation to threaten life, there would already be too much chaos on earth and vastly reduce resources to coordinate and to complete mother ship´s construction. 

Moreover, the people who would be selected to board the ship would be probably 50,000 to 100,000 rather than 250,000 because much room aboard the ship to carry spare parts and construction materials and machinery would be necessary. Most of the people aboard the ship would either be scientists, engineers, or construction technicians who could both keep the ship going for its 80 to 100 year voyage and be able to build a habitation on the exoplanet. If the explanet were not completely friendly or conducive to life, they would need to be able to construct a habitation with an artificial environment. But what if the exoplanet could not sustain life at all or was already inhabited by intelligent and advanced civilizations? What would be plan B? How would the crew of the ship locate another planet and continue its time in space?