Decoding Starlight: Electromagnetic Radiation Quiz

If a hot dense object produces a continuous spectrum and this light then passes through a cooler gas, then the gas atoms will absorb specific photons corresponding to their energy levels; if these specific wavelengths are removed from the continuous beam, then the resulting spectrum will feature dark lines, which is defined as an absorption spectrum.

If Wien's Law states that the peak wavelength is inversely proportional to the absolute temperature, then as temperature rises, the peak wavelength must decrease; if the wavelength decreases, then the light shifts toward the blue/ultraviolet end of the spectrum.

If every element possesses a unique configuration of electron energy levels, then each element will absorb only specific frequencies of light; if we detect these specific "fingerprint" lines in a stellar spectrum, then we can logically conclude that those specific elements are present in the star's atmosphere.

If an atom absorbs a photon with energy matching the difference between electron shells, then the electron must transition to a higher state; if the electron moves to a higher state without being removed from the atom, then this specific process is termed excitation.

If a light source is moving away from an observer, then the waves are stretched as they travel; if the waves are stretched, then their wavelength increases; if the wavelength increases, the light appears shifted toward the red end of the spectrum.

If the Balmer Series is defined specifically by electron transitions involving the n=2 level of Hydrogen, then any absorption or emission line in the visible spectrum of a star relating to these transitions is part of this series; if we see these lines, then we are observing Hydrogen in a specific state of excitation.

If the color of a star is determined by its surface temperature according to blackbody radiation laws, then higher temperatures produce shorter (bluer) wavelengths; if a star is blue, then it must be hotter than a star emitting primarily longer (redder) wavelengths.

If a star is rotating rapidly, then one side moves toward us (blueshift) and the other moves away (redshift); if these shifts occur simultaneously across the star's disk, then the spectral lines will appear thickened or "broadened."

If the mathematical expression for the Stefan-Boltzmann Law is E=σT4, then the relationship between energy and temperature is exponential; if the exponent is 4, then the energy is proportional to the fourth power.

If an electron moves from a high-potential state to a lower one, then the law of conservation of energy requires the excess energy to be released; if this energy is released as electromagnetic radiation, then a photon is emitted.

If temperature affects peak wavelength, composition affects specific lines, velocity affects Doppler shift, pressure affects line width, and magnetic fields cause Zeeman splitting, then all these physical properties are encoded in the light we receive.

If spectral analysis allows us to calculate the abundance of elements based on line strength, and if Hydrogen lines are consistently the most dominant in the vast majority of stellar spectra, then it follows that Hydrogen is the primary constituent.

If an object emits light, then it must interact with the electromagnetic force; if "dark matter" is defined by its lack of electromagnetic interaction (it does not emit or absorb light), then it cannot produce spectral lines.

If stellar classification (OBAFGKM) is organized by decreasing temperature, then 'O' stars are at the start of the sequence; if 'O' stars are at the start, then they are the hottest.

If an atom is placed in a magnetic field, then its energy levels are split into multiple components; if these levels split, then the resulting transitions produce multiple closely spaced spectral lines instead of one.

If an object is a perfect absorber and perfect emitter, then its radiation curve is determined solely by thermal equilibrium; if this is the case, then it fits the scientific definition of a blackbody.

If a star peaks in the green wavelength, then it is also emitting significant amounts of red and blue light; if the human eye receives a mix of all visible colors from the peak of the blackbody curve, then the brain perceives the star as white, not green.

If the Sun has a cooler atmosphere (photosphere/chromosphere) surrounding its dense interior, then the atoms in that atmosphere will absorb specific wavelengths; if absorption occurs, then the spectrum will contain dark Fraunhofer lines.

If the Doppler Effect only measures the radial component of velocity (motion toward or away), then motion that does not change the distance between the source and observer creates no wave compression or stretching; if waves aren't stretched or compressed, then no shift occurs.

If stars act as blackbody radiators across a wide range of temperatures and involve high-energy processes in their coronae, then they must emit radiation across the entire electromagnetic spectrum, from long radio waves to short X-rays.