I think that we have all done it, boys and girls alike. Maybe it starts with tossing pine cones at a tree. Or maybe by tossing a rock or ball into the air to see if you can hit it with a handy stick. This game often changes into one of, “How high can I throw this ball?” And then it becomes, “Can I throw it so high that it won’t come down?” To our vast disappointment, no. It always comes back down. And it always will thanks to gravity (g). No matter how much force (F) we put into it, no matter how hard we throw it, it always comes down.
A recent NASA/AP article published in the online Herald out of Rock Hill, SC provided a picture of Russian astronaut Sergey Prokopyev flinging a small satellite into orbit from outside the International Space Station (ISS). The ISS is itself in orbit around the Earth at a velocity of about 5 miles per second. Sergey’s sturdy “fling” (the word used to describe the launch) imparted additional velocity (V) to the satellite as it traveled away from the ISS.
The satellite is …. – wait! What is the satellite for? That information is hard to find; I will keep looking for it. But the interesting part of the NASA/AP release (no pun intended) is the novel approach to the satellite launch. When I think of a satellite launch I picture massive engines belching fire and towering rockets boosting bus-size devices to be hurled into space. In the time since satellites were first launched in the 1960’s, improvements in technology have allowed satellites to shrink so that now there is a distinct class of satellites that go by various names such as cube-sats, mini-sats, and nano-satellites. NASA Ames Research Center (ARC) has been working to guide the development of this area of space science over the last decade or more, and since 2016 ARC has hosted the Small Spacecraft Systems Virtual Institute (S3VI). The S3VI provides information on the state of the art of small space craft technology which includes nano-satellites and other space craft weighing less than 180 kg (up to about 400 pounds). The larger satellites at the higher end of this scale dwarf the nano-satellites such as the tissue-box size Sirius recently launched from the ISS. All these “small” satellites still need to be carried above the Earth’s atmosphere by some rocket, but for these Sirius satellites I find their final launch/release quite amazing.
The Sirius “nano” satellite is described in the NASA/AP article as being about the size of box of tissues. “Nano” means one-billionth of a unit, but in this case it is used as a word for tiny or diminutive. The satellite is small enough to be held by one hand. According to the NASA released video (https://www.youtube.com/watch?v=APko4n4H8fc) it has a handle to make it easier to hold and launch.
“OK Sergey, you are a ‘Go’.” says the director. “Hold it by the handle and just deploy it.” And with that Astronaut Prokopyev achieves the dream of every child that has ever tossed a ball into the air; it does not come down. Of course it will eventually come down as gravity (g) plays its ruthless role and overcomes the imparted forces of the velocity (V) of the ISS and the force (F) of Sergey’s “fling”. Eventually gravity will tug the little satellite down into Earth’s atmosphere where it will burn up on re-entry.
But if Sergey was five years old and continued to look up after he had tossed the nano-sat, he would be excited to see the small, gleaming satellite continually traveling away from him until it disappeared from sight.
How thrilling to feel that you have won against gravity.
The picture is based on a Charles Schultz drawing of the ”Peanuts” character Charlie Brown. I know we all wish Charlie Brown the best of luck in hitting the big toss.
Watch for my article reporting back on what the satellite is for. Perhaps we will use a sling shot next time. Why not?