Hawkeyes in Space: UI Physics, Past and Present

<Ashley>

 On November 15th my group and I went to the "Hawkeyes in Space" exhibit. This exhibit was located in the Old Capitol Building. It was really interesting. We saw many historic pictures and objects. The whole exhibit was dedicated to objects in space. I thought it was really cool how this exhibit was displayed. There were many real props that people used in the past. I think most people do not know much about space because it isn’t something we think about in our daily lives.

I learned that there are many objects in space besides just planets, starts and the sun. Space is filled with microscopic particles that are constantly interacting with each other. Most of the discoveries about space were found only 65 years ago. I learned a lot about the sun. The sun lies in the middle of the solar system. It is the largest object in space containing 99% of the solar system mass. It is so large that over one hundred earths could fit inside the sun!

The sun was formed 4.6 billion years ago. Scientists believe that the sun was made from a large cloud of gas and dust also known as the solar nebula. The sun has several layers it is not just one giant hollow ball floating in space. The innermost layer is called the core. This is the deepest part of the sun. The core only makes up 2 percent of the suns volume but yet it makes up for half the weight of the sun. This means that the core is little in size compared to the rest of the layers but it is really heavy. The radiative zone comes after the core. Light from the core gets inserted into this zone but it takes a million years for a single photon to pass through the zone. This is because this zone is a thick layer. Next is the convection zone. This zone reaches up to the sun’s surface. This layer is filled with tons of convection cells. There are two types of convection cells, granulation cells and supergranulation cells. You would assume that because these are cells that they would be small but they are actually really large. Granulation cells are six hundred miles wide and supergranulation cells are twenty thousand miles wide!

            The light that we see from the sun comes from the photosphere. This is the lowest level of the suns atmosphere. The temperature of the photosphere is about 11,000 degrees Fahrenheit. The sun is made up of hydrogen and helium. It also contains oxygen, carbon, neon, nitrogen, magnesium, iron and silicon but in smaller amounts. The sun also contains sunspots. These dark spots on the surface of the sun. These spots tend to be cooler than the suns temperature. Sunspots happen because a magnetic field lines are emerging from the suns inner core. When there is more magnetic activity there are more sunspots. It just depends how much magnetic activity is going on. Coronal mass ejections also occur. They are the largest explosions of magnetic field and plasma from the sun’s corona. Coronal mass ejections have a big impact on Earth’s magnetosphere. They cause changes in space weather and also cause bright auroras. These ejections are created from very highly twisted magnetic field structures on the sun. Solar flares happen when magnetic energy that has been built up in the sun’s atmosphere is released. This causes a fast intense change in brightness. During a solar flare, contents from the surface of the sun is released into the solar system.

<Chanel>

The Students at the University of Iowa are studying the aurora borealis. The aurora borealis is also known as the northern lights. The aurora occurs near the South Pole. The flow of electrons and ions streaming from the surface of the sun is how the aurora gets energy. When the particles interact with the Earth’s magnetic field, energy is built up and then released. This happens when there is high latitude also known as the auroral oval. Electrons collide with atoms of nitrogen and oxygen in the atmosphere then some atoms emit some of this energy as visible light being the aurora. They use electron and ion detectors that measure the energy and direction that the electrons and ions have as they go into the atmosphere. In order to deliver their detectors to various places above aurora they use sounding rockets. The sounding rockets they use get their name from the nautical term “to sound” or record measurements. The rocket has two major parts, the engine and the payload. The engine is solid fuel rocket motors and the payload contains the instruments. The rockets also come in a variety sizes, some even have four stages like the Black Brant XII. The entire flight takes about ten to fifteen minutes but that is enough time for it to collect a lot of information which is sent by telemetry back to Earth. They normally launch the rockets from Poker Flat, Alaska the only high latitude auroral zone rocket launching facility in the United States. Other times they launch from Andoya Norway as well. During the Great Geomagnetic Storm of August 28- September 2, 1859 the New York Times reported that it was possible to read at night by the auroral light alone in the New England area. If a similar event was to take place today, it would cause widespread damage to modern technologies including satellites, power systems, and telecommunications. This threat has generated an interest in space weather forecasting. Earth is not the only planet with aurora. They have been observed on Jupiter and Saturn as well.

<Alexis>

The planets within our solar system are one complex but very interesting galaxy. The solar system has been around for 4.5 billion years, consisting of eight of the most complex planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. During our visit to the Old Capital basement, we learned many interesting facts and concepts about our solar system. Some important information was about our lovely planet, Jupiter. Jupiter is the largest planet within this system, the fifth planet from the sun and is widely known for its giant red spot. This giant red spot has been described as storm, like a hurricane storm. The color of the red spot is red and brown, and three times the size of Earth. This planet, unlike Earth, is mostly made up of hydrogen and helium. Jupiter is one of the planets that spins the fastest on its axis, for example it takes this planet under 10 hours to spin completely upon its axis (compared to Earth that takes 365 day).

During our visit to the space center in the Old Capital, we learned that several missions were sent by NASA to orbit Jupiter, but that the only successful mission to orbit Jupiter was Galileo. Gallieo is the first spacecraft that orbited Jupiter successful but orbiting completely around Jupiter with no trouble. This spacecraft was launched in October of 1989 from NASA. Space Shuttle Atlantis, and it arrived to Jupiter on December of 1995. This spacecraft discovered that Jupiter has about 63 moons, one of the moons being the largest within out solar system, Ganymede. This spacecraft also found that Jupiter has 3 rings wrapped around it. The first ring is flattened, the second one is similar to a cloud, and the third ring is transparent. Galileo also sent a probe towards Jupiter while orbiting this plan in order to distinguish the accurate measurements of the atmosphere, by measuring the water and chemicals within this planet. Although Galileo was a successful mission, it was destroyed on September 21, 2003. This is because NASA was trying to prevent any contamination to the moons.