Hey there and welcome to Life Noggin.
大家好！欢迎来到脑洞大开的生命奇想！
Triangle Bobert snuck into my lab and hit the big red button on the half gravity machine I told him not to go next to.
三角博贝特溜进我的实验室，按下了我不让他靠近的半重力机器的大个红色按钮。
I probably should have made the button a little smaller. That was my fault.
或许我应该做一个更小一些的按钮，这是我的错。
I was able to reverse everything, but it did have me thinking, what if this happened to your world. What if earth only had half its gravity? Well first off, just what is gravity?
后来，我阻止了半重力的情况发生，但是我也不禁思考起来，如果这种情况发生在现实世界呢？如果地球的重力只有现在的一半会怎么样呢？首先我们得知道什么是重力？
In general, we can define gravity as an attractive force that pulls two bodies together.
通常我们可以这样定义重力：重力是把两个物体拉在一起的引力。
It’s what keeps all of the planets in orbit around the sun and what keeps you from floating off into space.
重力使所有的行星都在轨道上绕着太阳运行，重力的存在让你不会飘向太空。
And anything with mass has gravity. The more massive something is, the greater its gravitational pull.
任何有质量的物体都有重力。质量越大的物体，其引力就越大。
So a big, massive planet like the Earth is going to pull you toward it a lot more than one of my small pizza bagels will.
所以，像地球这样一个巨大的星球跟我的一个小披萨百吉饼相比，前者对你的引力大得多。
let me just get in here really quick. Delicious.
让我快点吃到这个百吉饼，美味。
Distance also matters with gravity. The closer you are to something, the more gravity is going to draw you toward it,
距离也与重力有关。你和一样东西的距离越近，你们之间的引力就越大。
and the farther away you are, the weaker the gravitational force will be.
同样，你和一样东西的距离越远，你们之间的引力就越小。
Not only that, but gravity isn’t even the same everywhere on Earth.
除了距离因素，地球上各个地方的重力也不相同。
According to NASA and data from the Gravity Recovery and Climate Experiment, gravity is ever so slightly stronger over places on Earth with higher concentrations of mass.
根据美国国家航空航天局(NASA)和重力恢复与气候实验(Gravity Recovery and Climate Experiment)的数据，在地球上质量浓度较高的地区，重力会稍微强一些。
And these concentrations can even change over time.
这些浓度甚至可以随时间变化。
But what would happen if the gravity here on Earth was suddenly cut in half?
但是如果地球上的重力突然减半，会发生什么呢?

It’s pretty hard to tell exactly what would happen, especially since whatever would cause this sudden change would likely have other effects,
很难准确地说出将会发生什么，尤其是因为不管是什么因素导致这种突然的变化，它都可能会有其他影响，
but if we look at the universe around us, we can get a good idea of what might happen.
但是如果我们观察我们周围的宇宙，我们就会知道可能会发生什么。
To start off, you’d probably lose a bunch of weight.
首先，你可能会减重。
That’s because our weight isn’t actually a constant.
这是因为我们的体重不是恒量。
It changes depending on where we are in the universe since it’s determined by how much gravity is acting upon us.
体重取决于你在宇宙的什么地方，因为它取决于有多少重力施加在我们身上。
For instance, if you weigh 100 Newtons on Earth, then you’d only weigh about 17 Newtons on the moon.
例如，如果你在地球上重100牛顿，那么你在月球上大约只重17牛顿。
That’s because up there, you'd only experience about a sixth of the gravity you normally do on Earth.
这是因为月球的重力大约只有地球的六分之一。
So with half gravity, it makes sense that you’d only probably weight about half as much.
所以在半重力的情况下，你可能只有现在体重的一半。
That, if you survived, and everything on Earth seemed to carry on about the same but just with half gravity, there would likely be health consequences.
在这种情况下，如果你幸存了，而且地球除了重力减半之外其它一切照常，这时候可能就会有健康问题了。
That’s because your body is always working against gravity.
这是因为你的身体将会一直对抗重力。
Your muscles have to work against gravity even when you’re relatively still, your bones have to support your weight,
即使在你静止的时候，你的肌肉也会对抗重力，你的骨骼在重力的影响下也不得不支撑你的体重，
which is affected by gravity, and even your heart has to work against gravity to pump your blood throughout your body.
而且你的心脏也要对抗重力，以给你的全身供血。
So at half gravity, and half your weight, your heart would likely become weaker, your muscles might become smaller, and you could even lose bone mass.
所以在半重力的情况下，你的体重减半，你的心脏可能会变弱，你的肌肉可能会变少，甚至有可能造成骨质流失。
These are issues that astronauts face when experiencing weightlessness, so with half your weight, it stands to reason that similar things would happen but to a lesser extent.
这些就是是宇航员在失重时所面临的问题，所以体重减半的话，人们就会遭遇类似的问题，只是程度会小一些。
But that’s if everything carried on about the same, just with half gravity. If we actually suddenly lost half of the gravity on Earth, other things would probably change as a result.
但是这只是地球除了重力减半之外其它一切照常的情况。如果地球重力真的突然减半的话，其它事物的状况也会改变的。
One of those things would be escape velocity. Since the Earth would have less gravity, how fast you would need to go to escape Earth, otherwise known as escape velocity, would be less.
这其中就包括逃逸速度。既然地球的重力变小，人逃离地球的速度，即逃逸速度，也会变小。
This means that you wouldn't need to go as fast to get off this planet, which might be a good idea if all this gravity stuff actually happened.
这意味着人逃离地球的速度就不用现在这么快了，如果重力减少的事情真的发生了，这可能是个好想法。
Two tickets to Mars please! I would like to chill with the aliens.
给我来两张去火星的票！我想和外星人玩会儿。
Let us know in the comment section below what we should talk next!
请在评论区告诉我们下期你想讨论什么！
Curious to know what it would take for the earth to explode? Check out this video. It only carved out a chunk of Earth a few kilometers deep.
想知道怎样才能让地球爆炸吗？来看看这个视频吧。它只挖出了几公里深的一大堆土。
Asteroids that are bigger, denser, or made of different materials could have the ability to hit us with enough power to shatter our planet.
那些体积更大、密度更高或由不同材料构成的小行星，可能会有足够的能量撞击我们，将我们的星球撞碎。
As always, my name is Blocko, this has been Life Noggin, don't forget to keep on thinking!
我是宝高，这里是脑洞大开的生命奇想。思考不要停！