How do radio waves differ from visible light

Posted on February 11, 2018 by lin0214

Radio waves actually travel at the speed of light in vacuum, which is about 300,000,000 meters per second. It is fast enough for anyone on Earth to contact others on Earth in less a second. Radio waves are electromagnetic waves, so is light. The differences between light and radio waves are their frequencies and wavelengths.

Wavelengths with different sizes also have slightly different properties. For example,  radio waves have a longer wavelength and lower frequencies, so they are less energetic than visible light and that is why radio waves have relatively no effects on human body.

It is also because of their differences in frequencies and wavelengths, radio waves can pass through certain materials that visible light can not. However, when light encounters a thick and opaque material, it is likely to be reflected or absorbed. That is why, people can use cellular services inside buildings but can not do so in elevators.

 

427639_orig
Picture from Gilnahirk Action Group

 

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How do radio waves differ from visible light

Posted on February 11, 2018 by lin0214

Radio waves actually travel at the speed of light in vacuum, which is about 300,000,000 meters per second. It is fast enough for anyone on Earth to contact others on Earth in less a second. Radio waves are electromagnetic waves, so is light. The differences between light and radio waves are their frequencies and wavelengths.

Wavelengths with different sizes also have slightly different properties. For example,  radio waves have a longer wavelength and lower frequencies, so they are less energetic than visible light and that is why radio waves have relatively no effects on human body.

It is also because of their differences in frequencies and wavelengths, radio waves can pass through certain materials that visible light can not. However, when light encounters a thick and opaque material, it is likely to be reflected or absorbed. That is why, people can use cellular services inside buildings but can not do so in elevators.

 

427639_orig
Picture from Gilnahirk Action Group

 

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Blog 3 – The Great Collision

Posted on February 11, 2018 by natsastronomy

collision
A visual representation of our collision with Andromeda

Right now, everything in our universe is getting further and further away from us. Except for one thing. That one thing is Andromeda, the closest galaxy to our Milky Way. Instead of getting further away, Andromeda is actually getting closer and closer. Right now, we are getting closer at a rate of 300 kilometers per second. In a mere 4 billion years, our very own Milky Way will go through an epic collision with Andromeda. Except, the collision won’t be as epic as it seems.

Chances are, when the two galaxies collide, they will form one large galaxy. However, there will not be a huge explosion from the collision of stars and planets. In reality, the bodies are so far apart and there is so much space between each celestial body that it is very likely that most stars and planets will survive the collision untouched. That’s not to say the galaxy will look the exact same. There could be some new coloring from the collision, and definitely a new shape. It is uncertain if life on our would continue the same way, and if our galaxy would continue to operate in the same way. Guess we’ll have to just wait to find out!

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Blog 3 – The Great Collision

Posted on February 11, 2018 by natsastronomy
collision
A visual representation of our collision with Andromeda

Right now, everything in our universe is getting further and further away from us. Except for one thing. That one thing is Andromeda, the closest galaxy to our Milky Way. Instead of getting further away, Andromeda is actually getting closer and closer. Right now, we are getting closer at a rate of 300 kilometers per second. In a mere 4 billion years, our very own Milky Way will go through an epic collision with Andromeda. Except, the collision won’t be as epic as it seems.

Chances are, when the two galaxies collide, they will form one large galaxy. However, there will not be a huge explosion from the collision of stars and planets. In reality, the bodies are so far apart and there is so much space between each celestial body that it is very likely that most stars and planets will survive the collision untouched. That’s not to say the galaxy will look the exact same. There could be some new coloring from the collision, and definitely a new shape. It is uncertain if life on our would continue the same way, and if our galaxy would continue to operate in the same way. Guess we’ll have to just wait to find out!

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Blog 3 – The Great Collision

Posted on February 11, 2018 by natsastronomy
collision
A visual representation of our collision with Andromeda

Right now, everything in our universe is getting further and further away from us. Except for one thing. That one thing is Andromeda, the closest galaxy to our Milky Way. Instead of getting further away, Andromeda is actually getting closer and closer. Right now, we are getting closer at a rate of 300 kilometers per second. In a mere 4 billion years, our very own Milky Way will go through an epic collision with Andromeda. Except, the collision won’t be as epic as it seems.

Chances are, when the two galaxies collide, they will form one large galaxy. However, there will not be a huge explosion from the collision of stars and planets. In reality, the bodies are so far apart and there is so much space between each celestial body that it is very likely that most stars and planets will survive the collision untouched. That’s not to say the galaxy will look the exact same. There could be some new coloring from the collision, and definitely a new shape. It is uncertain if life on our would continue the same way, and if our galaxy would continue to operate in the same way. Guess we’ll have to just wait to find out!

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Gravity

Posted on February 11, 2018 by samssolarsystem

Gravity is a fascinating phenomenon of physics that is integral to understanding the universe.  Gravity keeps Earth in orbit around the sun, and the Moon in orbit around Earth.  Any object that has mass, also has gravity. Moreover, the gravitational force between two objects is caused by two factors: mass and distance.  The gravitational force between two large objects at the same distance is greater than the gravitational force between two smaller objects.  Furthermore, the closer the distance between two objects, the greater the gravitational force.  The gravitational force between two objects can be summarized by the equation F = G * M1M2/r^2, where G is the gravitational constant, M1 is the mass of object one, M2 is the mass of object 2, and r is the distance between the two objects. As you can see, the force of gravity changes by object or planet.  Thus, an object’s weight — the force of gravity acting on an object — changes based on location, as the forces of gravity change from one planet to another (see below).  So, a person’s weight on Earth is more than their weight on Mars, but less than their weight on Jupiter.  This is because Mars is less massive than Earth, while Jupiter is more massive than Earth.  As a result, Mar’s gravitational force acting on an object on its surface is less than Earth’s, which in turn is less than Jupiter (which is more massive than Earth).  Note, a person exerts the same gravitational force on Earth (or any object they are on) as the Earth does on that person.  Yet, since the Earth is exponentially more massive than that person, your gravitational force is all but negligible on the planet, while the planet’s gravitational force keeps you from floating off into space.

Infographic showing how much you'd weigh on other planets and the moon

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Gravity

Posted on February 11, 2018 by samssolarsystem

Gravity is a fascinating phenomenon of physics that is integral to understanding the universe.  Gravity keeps Earth in orbit around the sun, and the Moon in orbit around Earth.  Any object that has mass, also has gravity. Moreover, the gravitational force between two objects is caused by two factors: mass and distance.  The gravitational force between two large objects at the same distance is greater than the gravitational force between two smaller objects.  Furthermore, the closer the distance between two objects, the greater the gravitational force.  The gravitational force between two objects can be summarized by the equation F = G * M1M2/r^2, where G is the gravitational constant, M1 is the mass of object one, M2 is the mass of object 2, and r is the distance between the two objects. As you can see, the force of gravity changes by object or planet.  Thus, an object’s weight — the force of gravity acting on an object — changes based on location, as the forces of gravity change from one planet to another (see below).  So, a person’s weight on Earth is more than their weight on Mars, but less than their weight on Jupiter.  This is because Mars is less massive than Earth, while Jupiter is more massive than Earth.  As a result, Mar’s gravitational force acting on an object on its surface is less than Earth’s, which in turn is less than Jupiter (which is more massive than Earth).  Note, a person exerts the same gravitational force on Earth (or any object they are on) as the Earth does on that person.  Yet, since the Earth is exponentially more massive than that person, your gravitational force is all but negligible on the planet, while the planet’s gravitational force keeps you from floating off into space.

Infographic showing how much you'd weigh on other planets and the moon

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Blog 2 – Archeoastronomy

Posted on February 11, 2018 by natsastronomy

machupicchu
An image of Machu Picchu

For this post, I’ve chosen to write about archeoastronomy in the ancient Peruvian city of Machu Picchu. I will be visiting the city this summer, which is perfect for this blog! First, a little bit about archeoastronomy. Archeoastronomy is the study of astronomical knowledge from ancient societies and civilizations. Machu Picchu is hidden away in the mountains of Andes in the Cuzco region of Peru, and is estimated to have been home to around 500-750 residents when it was being inhabited. Within the city is buildings and temples that demonstrate the vast amount of astronomical knowledge these people possessed long before our time.

As time went on and more discoveries were made, it became increasingly clear the Machu Picchu was an astronomical observatory. One of the most fascinating, and well known, things at the site is The Intihuatana stone. Translated to English, it is the “Hitching Post of the Sun”. At around midday on each equinox, there would be almost no shadow on this stone, indicating the equinox. This would be a signal to begin religious ceremonies surrounding the holidays. This stone is only one of many fascinating devices used at Machu Picchu to gain insight into astronomy. I look forward to finding those devices this summer!

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Blog 2 – Archeoastronomy

Posted on February 11, 2018 by natsastronomy
machupicchu
An image of Machu Picchu

For this post, I’ve chosen to write about archeoastronomy in the ancient Peruvian city of Machu Picchu. I will be visiting the city this summer, which is perfect for this blog! First, a little bit about archeoastronomy. Archeoastronomy is the study of astronomical knowledge from ancient societies and civilizations. Machu Picchu is hidden away in the mountains of Andes in the Cuzco region of Peru, and is estimated to have been home to around 500-750 residents when it was being inhabited. Within the city is buildings and temples that demonstrate the vast amount of astronomical knowledge these people possessed long before our time.

As time went on and more discoveries were made, it became increasingly clear the Machu Picchu was an astronomical observatory. One of the most fascinating, and well known, things at the site is The Intihuatana stone. Translated to English, it is the “Hitching Post of the Sun”. At around midday on each equinox, there would be almost no shadow on this stone, indicating the equinox. This would be a signal to begin religious ceremonies surrounding the holidays. This stone is only one of many fascinating devices used at Machu Picchu to gain insight into astronomy. I look forward to finding those devices this summer!

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Exercising in Space

Posted on February 10, 2018 by adventuresinspace

Image result for space travel Picture Source

When asked what we want to be when we grow up as kids, many of us answer “Astronaut!” We imagine going into space is cool, and it is! Astronauts “floating” in space looks like the best thing ever. One thing we don’t know as kids is that astronauts don’t float in space, it’s actually quite opposite; astronauts are in a constant state of free-fall and are only stay in orbit around the earth because of the gravitational pull of earth. Because of the change in gravitational pull, astronauts’ daily life looks much different than ours. Astronauts must exercise more than a person on Earth because they have to prevent bone and muscle loss. As a result, they exercise for two hour each day. Luckily for them, gravity is on their side; lifting 200 pounds in space is much different than lifting 200 pounds on earth. Astronauts maintain an active lifestyle even when their feet can’t touch the floor.

What do you think working out while being in a constant state of free-fall would feel like?

A day in the life of an Astronaut

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