Mira's Science Blogs

The Solar System by Sea and Sky There are many things astronomers look for when finding life in space. The first and most important step is to look for other planets. Just because you may find a new planet does not mean it meets all requirements for life. To find other planets, scientists use two methods, the transit method, and the Doppler technique. The first method, called the transit method, is when scientists look in changes of brightness in stars. This change in brightness occurs when a planet orbits in front of it. It is easier to see a change for larger planets because they have a larger mass in front of the star. The next technique, known as the Doppler technique, occurs when we see a change in velocity of the star. The planet's gravity moves the star, which is called a 'wobble.' When looking for habitable planets, scientists look in something known as the habitable zone. This is where liquid water could be possible. The closer a planet is to the star it i...

Finding another Earth by NASA/Ames/JPL-Caltech Summary There are two techniques scientists use to detect new planets. Of these include the transit method and the doppler technique. Rather than simply looking through a telescope for planets, scientists study the stars. This is because stars are brighter and easier for data samples. If a star's brightness dims slightly, it means a planet is orbiting in front of it. This is the transit method. Another way we detect planets is by looking for changes in the star's velocity. This is the doppler technique. If the star moves slightly, it is caused because of the planet orbiting around it. The motion of a star caused by a planet is called a 'wobble.' The cause for the star wobbling is because the gravitational force from the star acts to keep the planet in orbit, and the force of gravity from the planet moves the star as the planet orbits. The pull results in the star's movement. The larger the mass of the planet, th...

Earth's Tides by National Geographic Summary We have all heard and seen tides, but what causes them, and how are they created? The position of the moon affects the tides. As you can see in the image above, the moon's gravity is pulling the body of water towards the moon. High and low tides are caused by tidal bulges.  Tidal bulges  occur when the body of water is pulled towards and away from the moon's gravity. The bulge facing away from the moon occurs because the Earth itself is pulled.  During a tidal bulge, there is a high tide, however, in between the two tidal bulges, there is a low tide. In the image above, you can see that the top and bottom of the Earth have low tides, whereas the sides have high tides because they are facing towards and away from the moon.  As well as the moon, the sun also influences the tides. When the high tide is high, and the low tide is low, it is a spring tide. Over a 15 -day period, the spring tide occurs on days 0 and 1...