April Astronomical Events

Star gazing is something that everyone can enjoy in ANY universe, and I plan to make my time on this planet pleasantly filled with it!

Here are a few things to look out for this month:

mercury
Mercury will be at its greatest eastern elongation, and visible at sunset on Monday, April 18.

full moon
Full moon happens on Tuesday, April 22.

meteor shower
Lyrids Meteor Shower can be observed Tuesday-Wednesday, April 22-23. The shower consists of debris from the Comet Thatcher.

meteor shower
Eta Aquarids Meteor Shower can be observed Friday-Saturday, May 6-7. The shower consists of debris from the Comet Halley.

MARCH: Gas Turbine Engines

In January, I studied the viability of using internal combustion engines commonly used in automobiles for my trans-dimensional rocket ship. Those types of engines ended up being too inefficient, and far too slow. But the research led me to another area of internal combustion engines—the gas turbine engine.

There are many different kinds of gas turbines, each with a slightly different design and used for different purposes, but one thing seemed common: they provide a great amount of thrust, which is exactly what I need.

Much like automobile engines, there are a lot of similar steps involved in a turbine engine’s ability to produce work; there is a compression stage, combustion stage, and a “power stage”, where the power produced by the combustion stage is turned into work by rotating the turbine. Of course, how the turbine engine achieves these stages is pretty different from piston engines, which I’ll get into shortly. I studied a turbine engine that looked most useful for my problem: the turbojet.

Turbine Engine Diagram Ia

First, incoming air goes through the air intake. The intake acts as a sort of diffuser. This allows the air coming into the engine to maintain the speed essential for combustion. In the turbojet engine in Figure I, the air passes by to an axial compressor. An axial compressor allows the air to remain parallel to the axis of the turbine while it is being compressed. The compressor stage consists of sets of blades—powered by the turbine shaft—which act as a means to increase the pressure of the air and get it ready for the combustion stage. The air—which contains the oxygen essential to combustion—enters the combustor.

Turbine Combustion Chamber Ia
The combustor consists of a fuel nozzle that sprays fuel into the chamber. The igniter then ignites the fuel, burning the fuel and the air that is allowed to enter the chamber through inlet air holes. The air that is now energized with heat from the combustion heats up the surrounding air and then pushes the higher energy, higher pressured air to the turbine.

The turbine blades use the energy from the passing flow to spin, which—much like the crankshaft in an automobile engine—rotates to produce mechanical energy which can be used for work. This work is used for electrical generation, as well as powering the compressor. After the expanded gases pass through the turbine blades, the engine is fitted with a nozzle. Nozzles use the properties between pressure and outlet flow area to increase the velocity of the exiting gases. The gases exit the nozzle at a speed which produces a lot of thrust—hence using these engines for things like planes, some of which can go several times faster than the speed of sound!

Of course, as I mentioned, there are loads of different types of turbine engines, and each one is used in a slightly different way. For example, the turbojet engines featured here are most efficient at high speeds. Engineers are still coming up with improvements for such systems to make them even more efficient and more versatile; each system has its pros and cons. For now, I think these turbojet engines are a good look at the basic functionality of a gas turbine engine.

I think these types of engines look very promising, but they are also very complex…and require an environment with an oxygen-rich atmosphere! As far as going fast in atmosphere, this definitely looks like the way to go! But where my trans-dimensional ship is concerned, I think I’ll have to look for something that provides a lot of thrust and uses a fuel source I can actually take with me.

So the search isn’t over yet, but I feel like I’m getting closer!

– Little T

March Astronomical Events

Star gazing is something that everyone can enjoy in ANY universe, and I plan to make my time on this planet pleasantly filled with it!

Here are a few things to look out for this month:

Equinox
The equinox  happens on Sunday, March 20, which marks the first day of spring!

full moon
Full moon happens on Wednesday, March 23.

lunar ecplise
If you live in the Southern Hemisphere, watch out for the lunar eclipse on Wednesday, March 23, also.

FEBRUARY: Voltaic Cells

Sweet sassy-molassy!

Energy sure is a hard thing to grasp—because energy in this universe just keeps slipping out of my tiny, half-metal hands! And I’m going to need a lot of it if I’m going to make it back to my own dimension any time soon!

Electrostatic forces are relatively strong forces and can either be attractive or repulsive. When harnessed in the right way, and electrical potential is created, and it can be very useful to doing all sorts of work.

Electricity is something that is very common on this particular earth, but the production of this energy seems to vary, a lot. Sadly, a lot of the energy still comes from chemical sources, such as natural gas and coal. These sources aren’t inherently bad, and they seem to be efficient enough to keep up with power demands, BUT…they do produce a lot of waste heat and chemicals that aren’t doing very nice things to the environment.

I think it seems unfortunate more renewable power sources haven’t been exploited in the regions of this world with power demands. Perhaps a better energy source can be found? Or maybe the common archaic power distribution system can be upgraded to mitigate the demand?

Anyway, back to my research— Experimenting with the various types of ways to produce electrical currents, I stumbled upon a simple recipe for electricity: a voltaic cell.

Voltaic cells use the chemical properties of metals and oxidation-reduction reactions to form a circuit which can produce electricity—a flow of electrons. It is an example of a source of chemical energy, but in a different way than what I explored last month with combustion reactions.

Little T’s Research Notes: Zinc-Copper Voltaic Cell (not to scale):

Voltaic Cell Figure I Colour
Voltaic cells are broken into two halves. Each half contains an electrode. In the zinc-copper voltaic cell, the electrodes are the zinc and copper rods. The zinc and copper rods are placed in separate solutions of zinc nitrate and copper nitrate respectively. Note: other ionic compounds which can dissolve in solution can be used as well—it only needs to be a compound which will not react with the metals used as the electrodes! And don’t forget the salt tube which bridges the gap between the two halves— this AND a conductive wire connection between the two electrodes is needed to complete the circuit.

Voltaic cells use oxidation-reduction reactions—a chemical reaction in which a chemical species reacts with another to lose electrons (oxidizes) to become more positively charged, and the other chemical species reacts to gain the others electrons (reduces) to become more negatively charged.

As you can imagine, with electrons being sort of exchanged in this reaction, it’s the perfect recipe for electrical current. Voltaic cells use the spontaneity of this reaction to produce a steady flow of moving electrons, and thus a source of electrical energy.

Voltaic Cell Figure II
The anode—the zinc rod—is the negative half of the cell, and here’s why:
Zinc is a metal that is more likely to oxidize—get rid of its electrons—so solid zinc atoms become positively charged zinc ions and electrons which are now in solution:
oxidation half reaction
Due to electrostatic properties, like charges repel each other, so the electrons begin to trek towards the cathode half of the cell. The salt bridge of sodium nitrate between them helps this flow.

Voltaic Cell Figure III
The cathode—the copper rod—is the positive half of the cell. In this reaction, the copper acts as the oxidizing agent, which is another way of saying it is greedy for electrons. Despite gaining electrons to it, it is called the reduction half of the reaction because its over all charge is reduced, or becomes more negative. Since the copper ions already in solution are positive, they become copper metal, and migrate to the copper rod.
reduction half reaction
The salt bridge allows electrons to flow between the two halves.

Theoretically, I should have gotten a reading of 1.10 volts from the voltmeter when I tested this cell. I got around 1.0 volt that varied—which seems perfectly acceptable for a test conducted with scraps I found around the lab.

Of course, after I had completed several hours of tests on the cell, a nice human presented me this:
battery
A portable battery! It was a relief to know that batteries—upgraded versions of voltaic cells—have been  in circulation on this planet for a while now. And luckily, engineers and scientists and still working to make them even better.

A lot more research needs to be done before I can figure out if battery power is the way to go in my trans-dimensional ship repairs, but for now, I’m happy that I can use them for nearly everything else! I can see a lot of potential for batteries in my circuitry—but that will be research best left to a later date.

-Little T

Notes from the author:
Don’t go playing around with chemicals or electricity all willy-nilly, dear readers, as both can be very dangerous! Experiments should be done in labs only, with proper safety equipment, and under the supervision of a professional! 🙂

 

 

February Astronomical Events

Star gazing is something that everyone can enjoy in ANY universe, and I plan to make my time on this planet pleasantly filled with it!

Here are a few things to look out for this month:

full moon
Full moon on Monday, February 22.

jupiter
Jupiter will be most visible on Tuesday, March 8. IF you have a telescope, and wanted to see Jupiter, its moons, and the great red spot, this night would be the night to do it!

solar eclipse
And if you live in Indonesia or northern Australia, look out for a total/partial solar eclipse—but not directly at it, of course.

 

January Astronomical Events

Star gazing is something that everyone can enjoy in ANY universe, and I plan to make my time on this planet pleasantly filled with it!

Here are a few things to look out for this month:

full moon
Full moon happens on Sunday, January 24.

mercury
Mercury will most visible just before sunrise on Sunday, February 7.

JANUARY: Internal Combustion Engines

One of the troubles of getting around from one place to another in any universe is the distribution of energy. Thanks to the laws of thermodynamics, it’s always about making a system do as much work as possible, with the most efficient use of energy.

The concept of transferring chemical energy into usable mechanical energy certainly isn’t exactly new—which brought me to my first research project: the internal combustion engine. People of this world seem to use the things to get around everywhere and have no idea how they work!

Like with any system, energy can be lost before it can be transferred into work, but a lot of years of science and engineering has produced some pretty amazing systems. And engineers continue to work on improving these systems to make them even better.

The basic concept to an internal combustion engine uses the ideal gas laws and combustion reactions to rotate a crankshaft. The rotation of the crankshaft is where the chemical energy from the reaction is transferred into mechanical energy (specifically, a type of mechanical energy called rotational energy, imagine that!), which is used by the rest of the engine to do work—in other words, the engine is able to rotate the wheels and move the vehicle.

Little T’s Research Notes: Four stroke internal combustion engine (not to scale):

ICE stroke 1 intake
Here’s the first stroke: Gas intake.
The valve opens to allow a mixture of some hydrocarbons (usually gasoline) and air (which contains oxygen) into the cylinder. The crankshaft—which has an initial rotation—will cause the piston to move vertically in the cylinder.

ICE stroke 2 compression
Second stroke: Compression.
The piston is on its way towards the top of the cylinder, with the fuel and air mixture being compressed as it goes.

ICE stroke 2-3
At the end of the second stroke, the piston is is the top dead center position, where it and its connecting rod are parallel to the crankshaft. With the gasses fully compressed, the engine is ready to move on to the next stroke.

ICE stroke 3 spark
Third stroke: Power.
The power stroke is where the fun happens; the piston is ready to move down again, but without the energy to do it, the engine would seize. Instead, a perfectly timed spark from the spark-plug ignites the gasses in the cylinder, causing a combustion reaction. The combustion reaction is usually between the hydrocarbon octane and oxygen, and results in carbon dioxide gas and water vapor:
Combustion of octane
Since combustion reactions are exothermic—meaning the reaction gets rid of heat to the its surroundings, and heat is a form of energy—and the gases produced by the reaction expand rapidly in explosive excitement, the piston has been energized enough to give the crankshaft more rotation, and thus the rest of the engine more overall power.

ICE stroke 4 exhaust
Fourth stroke: Exhaust.
Now that energy has been transferred to where it needs to go, the exhaust gases aren’t so excited anymore—and they’re taking up space in the cylinder that would spoil another combustion reaction. So the exhaust valve opens. A combination of gas behavior and the motion of the piston allows the carbon dioxide and water vapor to escape.

Then engines in most vehicles have a network of these cylinders to make up the whole engine. Each cylinder fires at the right moments to provide an efficient and usable flow of energy, and over time, power. Other parts—like the transmission, radiator, and more—are also required to transfer the rotational and heat energy into work and keep the whole system running efficiently.

Unfortunately, carbon dioxide has a lot of negative effects to the atmosphere of this world, which means more research should be done to improve this type of engine, fuel, and exhaust. Maybe I can find a fuel source that doesn’t give off harmful chemicals? That’ll be research for another day!

So, I’m not sure I’ll be able use the internal combustion engine (as it is) to help me get back to my own dimension, but I definitely think it has potential to help me in other ways, while I’m here!

-Little T