1. What are exoplanets?
Exoplanets are planets out with of our solar system, which orbit stars which are not our Sun.
2. Why can’t we detect exoplanets by direct observation?
Even using telescopes, we cannot directly observe exoplanet as these exoplanets are too close to their star in which they orbit, in terms of the perspective we have on Earth.
3. What are the main ways in which exoplanets can be detected?
Exoplanets are easier to observe through indirect observation. These take three main types:
Astrometric Methods – investigate the planets motion and wobbles due to the gravitational forces which exist between the exoplanet and its star. However, no exoplanet has been detected by astrometric methods yet, as the wobbles are simply too small to detect at the huge distances between the Earth and other stars.
Radial Velocity Methods – This requires the light given out by the star to be diffracted by a prism and split into a spectrum. Emission lines can be gained from this spectrum, which relate to the wavelength of light absorbed by atmospheric chemicals in the star. Emission lines thus allow scientists to work out whether a star has a planet orbiting it, as due to a gravitational field, the planet causes the star to wobble, indicating that there is a planet orbiting the star. However, radial velocity methods cannot detect Earth
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Each element has a different set of lines which appear on a spectrum and so scientists can work out what exactly is in each stars spectrum. Spectral lines allow scientists to work out the elements present in the stars atmosphere, but also the temperature of the element in the star, the density of the element, the stars magnetic field, and the width of the line allows scientists to work out how fast the element is moving, letting us see if there are winds present in the star for example. A spectral line which gets stronger and weaker alerts is to physical changes on the
The two astronomers found many patterns after developing their graph. They found that 90% of stars graphed fell within a band that ran through the middle of the graph. These stars range from cool, dim, red stars at the lower right of the H-R Diagram to hot, bright, blue stars at the upper left corner of the H-R Diagram. The stars that fall into to this band are known as main-sequence stars. Stars such as the sun, and almost every start visible in the night sky fall within this band of main sequence stars. There is another group of stars which are cool and bright that appear near the upper right corner of the H-R Diagram.
The purpose of this lab was to understand the relationship between emission spectra and atomic structure using small samples of 7 chloride salts of different metals. Emission spectra(or line spectra) is a collection of wavelengths representing different energies. Electrons in an atom occupy different energy levels and are in the ground state when they are at a low energy level. When they start to enter a higher energy level after gaining energy, they start to enter their excited state. Once in their excited state, they proceed to go back to their respective energy level by emitting light in the form of a
The research area of detecting exoplanets, planets outside our own solar system, is a huge area of interest and funding. The importance of being able to detect these planets is they can give us information and an insight into planetary formation, to help the search for ”Earth- like” planets in the habitable zone, and of course the ever-present question of extraterrestrial life. So on order to attempt to gather information about these things we must be have solid detection techniques in place for exoplanets. A few of the important methods shall be discussed here, including the radial velocity method, transit method, direct imaging and gravitational microlensing among others .
There is a cultural assumption that there are many alien civilizations in the universe. However, what do we really know about extraterrestrial life? With recent findings of water on Mars and the discovery of Trappist-1, there could be hope for extraterrestrial life out in the universe. Even though the water on Mars is frozen under the polar ice caps and Trappist-1 could be far from finding any alien life, there are still many articles supporting the research and looking forward to finding additional news. In the article “Could the TRAPPSIT-1 worlds harbor alien life?’ written by Liz Fuller-Wright, she reports the announcement of astronomers that they found a miniature solar system of seven Earth-sized planets. Furthermore, the argument is effective towards bright individuals because it makes one think about what it will be if there was actually life outside of Earth.
To better understand the planets, we need to first have a basic understanding of our
Although carbon stars are the reddest of the red stars, there are different levels of red in these stars. Astronomers determine a star’s redness by observation and simple math. They measure the star’s magnitude through blue (B) and visual (V) filters. Then they subtract the visual magnitude from the blue. This leaves a number designated B-V called the color index. The more positive the color index, the redder the star is.
Whether it is a full moon, a waxing crescent, or a new moon, many wonder what is out there. If there is more to the universe, than just Earth. The Moons of Jupiter are an unknown topic to many, and there are many interesting facts about it. Galileo Galilei, born in 1564 played a huge role in most of the science we know today, and it is because of him we are beginning to understand the moons of Jupiter. All these moons of Jupiter’s have their own reason as to which they stand out why. All in all, even though the moons of Jupiter’s are unknown to many, it is an important piece to connecting the puzzle in our universe.
Kepler’s primary mission is to discover extrasolar planets within a habitable zone that have sizes relatively similar to that of Earth’s; previous planetary research detected giant planets that were much more massive than Earth. In addition to detection, Kepler is designed to examine the planets and stars that reside in the Earth-like planet’s system. Analysis includes how many planets and stars are in the system, orbit ranges, masses, densities, and whether there are any giant planets in the system. According to the NASA Exoplanet Archive, Kepler has found 961 confirmed exoplanets in more than 76 stellar systems, as well as 2,903 unconfirmed planets.
...nce. The intensity of the light reflected from the sample substance is also compared to the light intensity before it passes through the material. The basis of this spectroscopy is based on the concept of electronic transition. The pi electrons (electrons in a pi bond) can become excited as the molecule containing them absorbs ultraviolet and/or visible light. As a result, the electrons move to a higher anti-bonding molecular orbital. This orbital holds an electron that is located on the outside region between two nuclei. In other words, an anti-bonding orbital contains lone pairs of electrons. The difference in the orbitals determines the wavelength and frequency of the light that was absorbed by the substance. This collected data allows scientists to infer the identity of the compound. Generally, this spectroscopy is used frequently for quantitative measurements.
Although Pluto was discovered in 1930, limited information on the distant planet delayed a realistic understanding of its characteristics. Today Pluto remains the only planet that has not been visited by a spacecraft, yet an increasing amount of information is unfolding about this peculiar planet. The uniqueness of Pluto's orbit, rotational relationship with its satellite, spin axis, and light variations all give the planet a certain appeal.
Later after Copernicus came Johannes Kepler and Galileo Galilei, who confirmed some of Copernicus’ observations. Kepler provided concise evidence of planetary motion regarding their path around the s...
A star begins as nothing more than a very light distribution of interstellar gases and dust particles over a distance of a few dozen lightyears. Although there is extremely low pressure existing between stars, this distribution of gas exists instead of a true vacuum. If the density of gas becomes larger than .1 particles per cubic centimeter, the interstellar gas grows unstable. Any small deviation in density, and because it is impossible to have a perfectly even distribution in these clouds this is something that will naturally occur, and the area begins to contract. This happens because between about .1 and 1 particles per cubic centimeter, pressure gains an inverse relationship with density. This causes internal pressure to decrease with increasing density, which because of the higher external pressure, causes the density to continue to increase. This causes the gas in the interstellar medium to spontaneously collect into denser clouds. The denser clouds will contain molecular hydrogen (H2) and interstellar dust particles including carbon compounds, silicates, and small impure ice crystals. Also, within these clouds, there are 2 types of zones. There are H I zones, which contain neutral hydrogen and often have a temperature around 100 Kelvin (K), and there are H II zones, which contain ionized hydrogen and have a temperature around 10,000 K. The ionized hydrogen absorbs ultraviolet light from it’s environment and retransmits it as visible and infrared light. These clouds, visible to the human eye, have been named nebulae. The density in these nebulae is usually about 10 atoms per cubic centimeter. In brighter nebulae, there exists densities of up to several thousand atoms per cubic centimete...
Individual atoms can emit and absorb radiation only at particular wavelengths equal to the changes between the energy levels in the atom. The spectrum of a given atom therefore consists of a series of emission or absorption lines. Inner atomic electrons g... ... middle of paper ... ... a sensitive multielement inorganic analyses.
Our solar system has eight planets, their moons and satellites, and they are all orbiting the Sun. The eight planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto used to be the ninth planet but IAU changed the definition of planet and Pluto did not meet the standards so it is now a Dwarf planet.
Also, he discovered that light could be split into a visible spectrum of colors. Spectral colors from stars would later be used to determine their size, temperature, chemical composition, and even the direction the star is moving. Today, professional astronomers play a very different role than hundreds of years ago. Surprisingly, astronomers today spend minimal time at the telescope gazing at the night sky. Operating planetariums, teaching astronomy classes, or operating and maintaining an observatory are some of the things astronomers today do.