Showing posts with label Science. Show all posts
Showing posts with label Science. Show all posts

Thursday, April 25, 2019

Forensic Firearm Examination

We just learned about Ballistic Fingerprints.

Another type of science is Forensic Firearm Examination.

When guns are made, they are each given a special different code number called a "serial number".
No two guns have the same number, and when someone buys a gun they keep track of who owns which gun with which serial number.

This is done so that if a gun is used for a crime, the police can look at the serial number on the gun and figure out who owns the gun.

The serial number is printed right into the metal of the gun.
Sometimes people try to scrape off the metal where the serial number is, but police can use special electromagnets and chemicals to tell what the serial number was even if it has been scraped off.

Some guns these days are also being made to mark the serial number of the gun on the bullet when it is fired.
That way each bullet can be tracked down to who fired it if a crime is committed.

(from: wikipedia - forensic firearm examination)

Kid Facts - Blast from the past: Rocket Engine Nozzle

Thursday, April 18, 2019

Ballistic Fingerprints

We just learned about the Toxicology.

Another part of forensics is the study of Ballistic Fingerprints.

When someone uses a gun to shoot someone else, and they run away before the police can arrest them, there are ways that scientists can look at the bullets to try and figure out which gun they came from.

When a bullet is shot out of a gun, it spins around inside the gun's barrel.
This is a special thing called rifling, and it helps the bullet go straighter.
The way the bullet is spun around inside the gun leaves marks on the metal bullet.

If the police find the bullet that was used to shoot someone, and they find the gun that they think was used, they can test shooting another bullet out of that same gun and see if the marks on the bullets match.

They put both bullets under a microscope and if the lines match up, then they can use that as evidence to put a bad person in jail.

(from: wikipedia - forensic firearm examination)

Kid Facts - Blast from the past: Gas Rocket Propellants

Thursday, April 11, 2019


We just learned about the Fingerprints.

Another part of forensic science is Toxicology.

Long ago when someone died and it was a mystery, it was very hard to tell what happened.
If a bad person had killed someone by using poison, there was no good way to prove it so they could be sent to jail.

In 1832, a scientist named James Marsh came up with a test that could be used to show if a poison called arsenic was used to kill someone.
Arsenic did not have a smell or a strong taste, so people would sometimes sneak it into someone's food to poison them.
With the Marsh test, they would take some liquid from the body of the person that was poisioned.
Either some blood, or saliva (or spit) from their mouth, or urine from their bladder.
That liquid would be put into a bottle with some other chemicals, then burned up with some other gases, and then if it left a silvery black stain after being burned, it was proof that arsenic was used.

After Marsh proved to everyone that this test worked, it was used by police all over the world to put people in jail for trying to poison other people!

Because this worked so well, people worked on coming up with other ways to test for chemicals in a person's body.
These days scientists can test hair, blood, saliva, sweat or even food that is in the intestines that was not totally digested yet.

Toxicology helps the police prove what the truth is, using the evidence that is in the body!

(from: wikipedia - marsh test)

Kid Facts - Blast from the past: Liquid Rocket Propellants

Thursday, April 4, 2019


Let's keep learning about Forensics, the science of a detective!

Another part of forensic science is Fingerprints.

Everyone's fingers have tiny little ridges that are made over years and years of touching things.

The skin on the hand is the epidermis, and the fingerprints are called epidermal ridges.
These little ridges stick up, and have oils on them that is made by the skin.
When a person touches something, the oil from the ridges leaves a mark.

A good way to test it is to touch a mirror or a piece of glass, and it should show the finger print.

Detectives figured out that using a little brush with some ink on it, they could find fingerprints on windows, desks, or anything a person touches.
To match up the fingerprints, they take a persons finger and get ink on it, then make a mark on a piece of paper.
If the paper mark matches the one they found, then it is for sure a match, as no two people have the same fingerprints.

There are special names for some types of shapes on the fingerprints, like arch, loop, and whorl.

(from: wikipedia - fingerprint)

Kid Facts - Blast from the past: Solid Rocket Propellants

Thursday, March 28, 2019


We just learned about the Falcon Heavy rocket engine made by SpaceX.
From rocket fuel to navigation systems to the history of rockets, we've learned a whole lot about rockets!

Let's move on to something new, called Forensics!

This is the science of figuring out things that happened, by looking around for clues.
The word "forensic" comes from the Latin language and means "of or before the forum".
In the old days when someone did something bad, they would have to come before a group of people called a forum and tell them what happened.

When detectives and police officers are working to solve crimes, they use forensic science to look around at the place where the crime happened and see if they can figure out what really happened.

This can be things like fingerprints, talking to people who saw the crime, or even looking at what kind of animals are in the area!

Famous detectives from books like Sherlock Holmes were experts in forensics and could figure out any crime that happened!

(from: wikipedia - forensic science)

Kid Facts - Blast from the past: Rocket Propellant

Thursday, March 21, 2019

Falcon Heavy

We just learned about the Falcon rocket.

Another SpaceX rocket is the Falcon Heavy.

This rocket is a lot more powerful than just one Falcon rocket, and it is being made to hopefully some day take people into outer space, to the Moon or even to Mars!

It is made from three "Falcon 9" rockets strapped together.
The one in the middle is the core main rocket, and the two on the outside are booster rockets.

This rocket can carry a lot of weight, about 141,000 pounds into outer space!
On the first of the Falcon Heavy rocket launch, the owner Elon Musk sent his car into space, a shiny red Tesla Roadster, and they also put a fake person inside in a space suit, and nicknamed him "Starman".

When the space craft makes it up into space, the Falcon 9 rockets actually fall off the main spacecraft and fall back to earth.
They don't crash into the ocean though, they actually use guidance systems to come back down to the ground and land safely on a launch pad so they can be used again!

(from: wikipedia - falcon heavy)

Falcon Heavy boosters landing - SciNews

Kid Facts - Blast from the past: Rockets

Thursday, March 14, 2019


We just learned about the Space Shuttle.

Another famous rocket is the Falcon made by SpaceX in 2008.

In 2002 the SpaceX company was started by Elon Musk as a way to try and build rockets to go to outer space and even someday Mars!

The big difference with SpaceX is that it was a business that was in charge, instead of a people that worked for the government like USA or Russia.

These rockets were two stage, and made to use liquid rocket fuel.
Elon Musk said that the name of the Falcon rocket came from the Millennium Falcon from Star Wars!

(from: wikipedia - falcon 1)

Kid Facts - Blast from the past: Speleoseismite

Thursday, March 7, 2019

Space Shuttle

We just learned about the Ariane rocket.

Another famous rocket is the Space Shuttle, made in the USA in 1981.

This was a kind of airplane made for doing work in outer space, and then bringing people home.
The space shuttle had two big rockets to help it launch called "Solid Rocket Boosters" or SRBs.
These are the tall skinny white rockets on either side of the shuttle.

These SRBs used solid rocket propellant, together weighed about 2.6 million pounds, were about 150 feet long, and 12 feet wide.
When the shuttle was launched, these rockets helped bring it to 28 miles up into the sky, at a speed of over 3,000 miles per hour.
They used gimbaled thrust like we learned about, to tilt the engine nozzle and steer the rocket, and they used gyroscopes to make sure they were going the right way.
After these rockets ran out of fuel, they would let go of the shuttle and fall to earth with a parachute.
When they made it down to earth, they were found and fixed up and reused over and over again.

The Space Shuttle main engine, called the SSME uses liquid fuel, and has three rocket engines with nozzles at the bottom of the space shuttle.
These engine nozzles also used gimbaled thrust, just like the SRBs.
It holds its fuel in a giant fuel tank called the Space Shuttle external tank (ET).
The ETs weighed over 70,000 pounds, was over 150 feet long, and 27 feet wide.

During launch, the SSME would burn the fuel in the fuel tank for about eight minutes, and then it would drop off the ET which would fall into the ocean and never be reused.

After it was coming back from space it used small thrusters called the Reaction Control System or RCS to help steer it down, and then it mostly flew down to earth like a glider.

The space shuttle flew 135 missions into space, from 1981 to 2011.

(from: wikipedia - space shuttle)

Space Shuttle Launch Audio - play LOUD (no music) HD 1080p - indiegun

Kid Facts - Blast from the past: Seismite

Thursday, February 28, 2019


We just learned about the SM-65 Atlas.

Another famous rocket was the Ariane.

In Europe, a few countries worked together to make a rocket that would be used to launch things up into space, like satellites or even for space exploration.

France, Germany and the UK came up with it and its first launch was in 1973.

They were multi-stage rockets, using liquid rocket fuel.
These rockets change a little every few year, but some are still mostly working today, launching satellites and exploration things into outer space.

(from: wikipedia - ariene (rocket family))

Kid Facts - Blast from the past: Mercalli Intensity Scale

Thursday, February 21, 2019

SM-65 Atlas

We just learned about the R-7 Rockets.

Another famous rocket in history is the SM-65 Atlas.

After the Russians had developed missiles that could go from one continent to another, the USA worked to try and do the same so they could have the same kinds of weapons.

The SM-65 Atlas was the first rocket that the US made that was an ICBM, meaning it could fly all the way to another continent.

It was made in 1959, was over 75 feet tall, and weighed over 260,000 pounds.
The rocket fuel was liquid oxygen, held in thin stainless steel tanks that were held in place by the pressure of being full of fuel like a balloon.
It used radio guidance to keep it's path, and vernier rockets to help make small steering changes.

This rocket type was used for many years, and was the one used for the Mercury space program that launched American astronauts into orbit.

(from: wikipedia - sm-65 atlas)

Kid Facts - Blast from the past: Richter Magnitude Scale

Thursday, February 14, 2019

R-7 Rockets

We just learned about the PGM-11 Redstone.

Another type of rocket from history is the R-7 Rocket.
Sometimes it's called the R-7 Semyorka, because the Russian word for seven is "Семёрка" which sounds like Semyorka.

After World War II when the Russians brought German scientists to work for their country making missiles, they learned a lot about making missiles, and made the R-1, R-2, and R-5 missiles.
Then they sent the Germans home and started making their own missiles.

The Russians made a missile called the R-7, and it was the first "ICBM" missile which stands for "Intercontinental Ballistic Missile".
This means it could be launched from one continent like Europe or Asia, and fly all the way in the air to land on another continent like North America.

For the first time in history, someone could launch a missile from over 5,000 miles away to bomb another city.
Because this was such a scary thing, it pushed the scientists in the USA to try and make their own ICBMs to fight back if they were being bombed from across the Atlantic ocean.

The R-7 rocket was not just used for war, it was used for space exploration.
Sputnik was the first satellite to be launched into space to orbit the earth.
In 1957 the Russians used a type of R-7 rocket to launch it up into space.
This also pushed the other countries of the world like the USA to make rockets for space exploration.

(from: wikipedia - r-7 (rocket family))

Kid Facts - Blast from the past: Seismogram

Thursday, February 7, 2019

PGM-11 Redstone

We just learned about the V-2 Rocket.

Another famous rocket from history is the PGM-11 Redstone.

This was an American rocket made from the German scientists who had made the V-2 rocket.

It was part of the American rocket program for a very long time.
This rocket was the first one to carry a nuclear bomb, that was exploded up in the atmosphere in the sky.
It was also part of the rocket program to launch the US Explorer 1 space satellite.

The family of rockets that were made as copies of this later went on to send a person into space!

(from: wikipedia - pgm-11 redstone)

Kid Facts - Blast from the past: Seismometer

Thursday, January 31, 2019

V-2 Rocket

We just learned about the Bell X-1.

Another part of rocket history is the V-2 Rocket.

During World War II when everyone was making rockets for war, the Germans made a rocket called the V-2.
It came from the German words "Vergeltungswaffe 2" meaning "Retribution Weapon 2".

It was the world's first missile that used a guidance system to make sure it hit the target.
The rocket used ethanol and liquid oxygen for its propellant, and launched itself into the air for 65 seconds.
After that it would start falling towards its target, and it used gyroscopes, accelerometers and tail fins to guide its path as it fell toward the target.

It was also the first man made object to go into outer space on June 20, 1944.

After the war, Great Britain, the USA, the Russians all used these rockets to help learn how to make rockets to launch into space.

(from: wikipedia - v-2 rocket)

Kid Facts - Blast from the past: Seismic Wave

Thursday, January 24, 2019

Bell X-1

We just learned about the World War II Rocket Weapons.

Another famous part of rocket history was the Bell X-1.

The Bell X-1 was actually a rocket powered airplane, that was built to go faster than the speed of sound, over 700 miles per hour!
It was made to be shaped kind of like a bullet, and with wings going straight out, not tilted back like most airplanes.

In 1947, pilot Chuck Yeager flew the X-1 to 700 miles per hour and broke the sound barrier.
The plane was carried up into the sky from another bigger plane called the B-29, and dropped so that it didn't have to launch itself.

The rocket engine on the back of the X-1 was the XLR11, the first liquid propellant rocket engine made in the US to be used in an aircraft.

It used ethyl alcohol and liquid oxygen as propellants, and had four combustion chambers.

(from: wikipedia - bell x-1)

Chuck Yeager Breaks the Sound Barrier -- X-1 -- 1947 - Motherboard

Kid Facts - Blast from the past: Induced Seismicity

Thursday, January 17, 2019

World War II Rocket Weapons

We just learned about the The Rocket into Planetary Space - Hermann Oberth.

Another part of rocket history are the World War II Rockets.

The science of making rockets has always been spread out between people who use them for fun to make big explosions,
people who try to make them for travel like flying into outer space,
and people who try to make them for war blow up and hurt people.

During World War II, there were many different types of rockets made for war.

Some were made for anti-aircraft, meaning they shot from the ground to try and blow up airplanes.
Others were made to launch from the ground and then land at another city and blow it up.
Still others were used to shoot from one aircraft to another.

The Germans and Russians were the ones that made the most rockets like the German Nebelwerfer or V-2, and the Russians RS-132 and Katyusha.

The Allied forces like the US or England made some ground to air rockets that they would attach to tanks or pull along like a wagon.

During this time the science of making rockets was all about war and who could blow up the other person.
It helped make the world of rockets better, but it also was very dangerous for the world as they killed over 10,000 people.
Even making these rockets was dangerous, and 20,000 people died in explosions when they were trying to make the rockets.

(from: wikipedia - bachem ba 349)

(from: wikipedia - nebelwerfer)

(from: wikipedia - katyusha rocket launcher)

(from: wikipedia - rs-82 (rocket family))

(from: wikipedia - t34 calliope)

Kid Facts - Blast from the past: Volcano Tectonic Earthquakes

Thursday, January 10, 2019

The Rocket into Planetary Space - Hermann Oberth

We just learned about the Le Prieur Rocket.

Another part of rocket history is the book The Rocket into Planetary Space by Hermann Oberth.

Oberth lived in Germany, and after reading the science fiction books by Jules Verne he loved thinking about rockets.
He became a scientist and wrote a book about launching rockets into space called "Die Rakete zu den Planetenräumen" which means "The Rocket into Planetary Space".

Later on he wrote another book called "Wege zur Raumschiffahrt" which means "Ways to Spaceflight".

In 1929 there was a movie called "Frau im Mond" which means "Woman in the Moon", and the director of the movie asked Oberth to make a fake rocket to use in the movie.

When it was made, the movie had the most real looking rocket ever made on film, with a multiple stage rocket, liquid fuel and other real parts of rocket science.

Oberth later went on to work for NASA to help make rockets for space flight.

(from: wikipedia - hermann oberth)

Kid Facts - Blast from the past: Earthquake Swarm

Thursday, January 3, 2019

Le Prieur Rocket

We just learned about the De Laval Nozzle.

Another part of rocket history is the La Prieur Rocket.

During World War I, a French scientist came up with the idea to shoot rockets from an airplane.
He made some rockets that were a lot like the old Fire Arrows, just a tube filled with gunpowder strapped to a stick.
Usually they would only go straight for a little over 100 yards.

People were worried that this would start the airplane on fire, so he tested it by strapping an airplane to a car and driving around, and shooting the arrows from the airplane on top of the car.
It worked, so they started putting them on airplanes in 1916.

The rockets were launched when the airplane pilot pressed an electronic ignition switch in the plane, and then the rockets would shoot off one by one.

They were mostly used to shoot down balloons that the enemy was using to spy on them.

(from: wikipedia - le prieur rocket)

Kid Facts - Blast from the past: Tsunami Earthquake

Thursday, December 27, 2018

De Laval Nozzle

We just learned about the Nell Rocket by Robert Goddard.

Another part of rocket science is the de Laval Nozzle.

When Robert Goddard was working on his rockets, he decided to use a type of nozzle that would have a pinch in the middle.
The smaller part of the nozzle puts pressure on the burning fuel, and it comes out at a supersonic speed, burning faster than the speed of sound.

The De Laval Nozzle was actually invented by a German engineer who came up with it for steam engines.

(from: wikipedia - de laval nozzle)

Kid Facts - Blast from the past: Supershear Earthquake

Thursday, December 20, 2018

Nell Rocket - Robert Goddard

We just learned about the L'Astronautique by Robert Esnault-Pelterie.

Another famous rocket was Nell made by Robert Goddard.

Goddard was a famous inventor who read about rockets in the books by Jules Verne and H. G. Wells, and came up with the very first rocket that used liquid fuel.
He named it "Nell" and launched it in 1926.
His team launched 34 rockets, going over a mile and a half in the sky, and over 500 miles per hour.

The work he did with rockets helped get people interested in space travel and rockets.

(from: wikipedia - robert h. goddard)

Kid Facts - Blast from the past: Submarine Earthquake

Thursday, December 13, 2018

L'Astronautique - Robert Esnault-Pelterie

We just learned about the Tsiolkovsky rocket equation.

Another part of rocket history is the book L'Astronautique by Robert Esnault-Pelterie.

Robert was a French scientist who was studying airplanes.
He made his own "REP" airplanes not long after the Wright Brothers in America made their first flight.

A while later he got very interested in space travel using rockets, and wrote some books and papers about using atomic power for jets.

He later worked with other scientists in France to try and make rockets using liquid rocket fuel, and worked so hard that one time after an explosion he lost three fingers from his right hand!

The vectored thrust that we learned about, where the nozzle is moved to steer a rocket was first invented by him.

(from: wikipedia - robert esnault-pelterie)

Kid Facts - Blast from the past: Slow Earthquake