Is There Life in Space? 5/23/19

Link by NASA Solar System Exploration

      We all know the typical sci-fi movie where an alien monster drops out of some unknown planet and takes control of the earth. We may laugh at this - the possibility of alien life somewhere out there - but it's a real possibility. For years, scientists have been striving towards one simple but very detailed question: is there life in space? The answer is entirely possible. We may not find extraterrestrial beings living across the galaxy within our lifetime, but with the knowledge scientists have now, it may be possible soon. There can be life out in space, but it isn't likely we'll find it soon. We're still a couple steps away from being able to hail our alien neighbors and bounce over to the next planet to meet them.

      Is there life in space? It's too complex a question for us to just say yes or no immediately without any thought. Scientists have, for decades, been experimenting with different methods and technologies to find planets that may be able to support life, and what qualities they need to make it possible. We all know the things we need to survive: water and oxygen. That's what scientists look for: a planet in the Goldilocks zone, where water can stay liquid on the planet's surface. Narrowing it down to planets around a life-supporting star and with water on the surface can help scientists find more potentially life-holding planets. Also, looking for a star that can support life is a good plus. Our sun is a star, and it can support life on our Earth. Stars are categorized by color and temperature. The hottest stars, colored blue, are not able to support life, so scientists ignore planets orbiting a star they already know won't be able to support life on it. The coldest stars, colored red, can support life, but the planet would need to be extremely close to it. Scientists watch the stars for planets because a planet would be dark against a dark sky, so a dark planet in front of a huge, illuminated star would make it easier to find for sure.

      There probably is life in space, somewhere out there. Since NASA's Kepler telescope launched in 2009, 21 planets less the size of Earth have been discovered - and in the region where liquid water could be possible. If a planet around the size of Earth with liquid water on it around a life-supporting star is found, life could definitely be possible out in space. The chances of finding it within the next twenty years are not very promising, but it might be possible after twenty years of more research. Scientists have come a long way since their telescope launched and have come across so many possible planets that it probably will happen, and soon. We just need to make sure that we don't tick off the aliens so that the rest of the extraterrestrial life hiding out there doesn't choose to suddenly attack Earth. That would be some way to discover it. 

Galaxies and Solar System 5/17

When we look up at the clear night sky, we may see something beautiful. We can see galaxies, stars and the vastness of our universe. Space goes on forever, much further than our own little eyes can see. And if we had a perfect telescope that could take us anywhere, we could see many interesting things.

Space is a clutter of stars, galaxies, planets and debris. All of these make up the beauty of our endless universe.

Galaxies
Galaxies are clusters of stars, planets and debris. They can be in three shapes, spiral galaxies, elliptical galaxies and irregular galaxies. All of these galaxies have a special shape and can be huge, thousands of light years long.

Link by JPL - NASA

Spiral galaxies are shaped like spirals. Our own galaxy, the Milky Way, is a spiral galaxy. Our solar system is located in the Orion Arm of the galaxy. The arm of a galaxy is one of the protrusions on the outside of the galaxy. Newer stars can be found in these galaxies, generally in the arms. About 77% of observed galaxies are spiral. 

Link by Wikipedia

Elliptical galaxies are shaped like ellipses. They are generally round, but are sometimes stretched longer along one axis that the other. Older stars can be found in these galaxies. 

Link by Flickr

Irregular galaxies are random and have no particular shape. This is generally because of the gravitational influence of other galaxies nearby. They lack distinct form and are irregularly shaped. These galaxies have dust and gas to form new stars and have many young stars.

Stars

Stars are made in dark molecular clouds. In the clouds, matter and dust collects together to collapse in gravity. Inside these collections, denser matter is formed into the core of the star. In the middle of the core, the matter is compressed and heats up, forming the light a heat that stars give off.

Link by Flickr

Space is filled with hundreds of stars. They can be in any shape, size or point in their life cycle. Our own sun is also a star, and there are many others around this size. Seeing the sun in pictures next to the planets makes us surprised at how big it is, but there are many other stars that can be hundreds of times larger and make the sun look tiny next to them. 

The video compares the size of the planets to the sun to some of the other stars in the universe. There are so many others that make the sun look puny, and while we think that it's huge, it really isn't compared to these supergiants.

Stars can be different colors, too. Our own sun is a yellowy orange. What temperature is this? We may say very hot. Red is hot and blue is cold. It says so on our bathroom water faucets and kettles and everything. In terms of stars, though, blue stars are actually the hottest. Red stars are the coolest. Not to say they aren't hot - they are - but they are considered the coldest stars. Red is the coldest, then orange, yellow, white and blue.

S&EP: Models

This week, I used models to examine the behavior of stars and planets. Scientists have tried for years to determine if there are other planets orbiting other stars, and whether or not they can support life. To do this, they can use two methods to determine if there are planets orbiting around stars like our planet and sun. Large planets are able to 'wobble' the star they orbit around. Sometimes the star will wobble a little bit, and sometimes it will wobble more. This is called the Doppler effect, and scientists use this to see if a star could be influenced by a planet. The second method is called the transit method, and to do this, scientists use telescopes to watch large stars like the sun. The light intensity of the stars will change if a planet passes in front of it. Scientists watch the stars rather than the planets because planets are dark against the dark sky, and it's easier to see the darkness against a star. These models helped me understand how stars and planets would really work in real life, and how scientists will both accurately and inaccurately study the stars and determine if there are other planets out there like earth.


XCC: Patterns

When studying the stars and trying to discover new things, scientists will look for patterns. Patterns like the transit method help them make new discoveries every day. This way, they can rely on more than one occurence of an event to see if they have accurate data. By watching to see if there is dimness in the stars, scientists can examine and record how many times this occurs and if it can be considered a pattern. If it is, it could be a planet orbiting that one star in particular. If it isn't, it could simply be an asteroid or other piece of debris floating around in space. Scientists look for these patterns because more than one occurence of these types of events can help explain and prove points they can try to make. Patterns are important in science because we can't rely on a single piece of evidence that only happened once; we need more background and a further understanding of the topic and data in order to be successful.

Seasons and Tides 5/3

Every year, every month, sometimes every day, they happen, and we usually don’t even notice. The seasons change like they always do, the tides go up and down as usual, and we will occasionally see the sun or moon eclipse. But we don’t really know what causes the seasons, tides and eclipses we see, and it all happens around us every day.

Tides
There are two high tides and two low tides every day. In the diagram of the Earth (below), the two blue bulges on the sides are called tidal bulges. As we pass through the tidal bulges, we experience a high tide.

One of the tidal bulges always points towards the moon, and the other points away from the moon. These bulges are the result of the moon’s gravitational pull on the Earth. Because the Earth has a gravitational pull of its own, most of the things on the planet are not influenced by the moon’s pull. However, the liquid water of the ocean is less influenced by the Earth’s gravity and is pulled slightly towards the moon. The moon’s gravity pulls the water towards and away from the moon.

When the tide is extremely high and the tide is extremely low, it is called a spring tide. When there is less of a difference between the heights of the tides, they are called neap tides. Neap tides occur when the gravity of the sun and moon pull on the Earth’s surface at a ninety degree angle. Spring tides occur when they pull in the same direction or in opposite directions.

Seasons

Seasons happen because of the Earth’s tilt on its axis. The Earth is tilted at a 23.5 degree angle on the axis and rotates around the sun. The Earth is split in half by the equator, the invisible line that wraps around the center. North of the equator is the Northern hemisphere, and south of it is the Southern hemisphere.

When the sun’s energy hits the Earth’s surface, most of it is absorbed by the equator. The North and South poles absorb the least, which is why they are so cold. It is colder at the poles that at the equator because more sunlight and solar energy reaches the equator than the poles. There is always a pole that is facing away from the sun and cannot reach them to give them light and warmth. The other pole cannot be reached because the equator is always facing the sun.

The seasons are caused by the Earth’s rotation around the sun and how it is tilted. No matter what season is going on in the Northern hemisphere, it is always the opposite in the Southern hemisphere and vice versa.

If it is winter in the north, it would be summer in the south. No matter what season it is, they are always opposites.

S&EP: Models
While studying how the seasons changed, it was helpful for me to refer to a model to see how it worked. The model I have constructed below shows how the seasons can be determined in any hemisphere in any position. For me, this was helpful because I could relate the amount of sunlight each hemisphere was getting with the season the was going on in each hemisphere.

This model helped me understand because I noticed that more sunlight can reach different areas better, which would mean that spring or summer would be in that position.

XCC Patterns
The seasons follow patterns often, and so do the tides. They follow the moon phases. The seasons follow with the Earth’s rotation and its tilt, which is why each season starts in roughly the same spot every year. The equinoxes and solstices are in the same months, because the seasons follow the same pattern. The Earth continues rotating in the same pattern, and the seasons follow with it.