The Sun
This process generates energy in the Sun.
What is fusion?
This unit of distance is approximately equal to 3.26 light years.
What is a parsec?
This is the reason an interstellar cloud collapses to form a star.
What are gravitational forces or external triggers?
This phase of a star's life describes when it is fusing hydrogen into helium in its core.
What is the main sequence?
This is the difference between a Type I supernova and a Type II supernova.
What is that Type I involves the explosion of a white dwarf in a binary system, while Type II involves the explosion of a massive star?
UH OH! PHD TIME!
This highly hypothetical phenomenon, requiring a specific combination of quantum tunneling and exotic nuclear interactions, could cause an ultra-rapid energy release in the solar core, resulting in a short-lived and localized increase in solar luminosity orders of magnitude greater than the typical solar output.
What is a hypothetical "solar hiccup" event, involving the simultaneous quantum tunneling of multiple protons leading to an instantaneous and localized chain reaction of nuclear fusion within the Sun's core?
This term refers to the brightness of a celestial object as seen from Earth.
What is apparent magnitude?
UH OH! PHD TIME!
The coupling between these two phenomena in the molecular cloud caused by the interaction of a certain type of radiation with a specific class of interstellar dust grains can result in a complex process that generates rotational-vibrational transitions in molecules that are detectable in the microwave region of the electromagnetic spectrum.
What is the coupling between the excitation of molecular hydrogen (H2) by far-ultraviolet (FUV) photons and the radiative torque (RAT) alignment of dust grains in the presence of an anisotropic radiation field?
This factor determines the main sequence lifetime of a star.
What is mass?
These are the possible outcomes for a stellar remnant after a supernova explosion.
What are neutron star, black hole, or complete dispersal of the material into the surrounding interstellar medium?
This layer of the Sun is where most of its energy is produced.
What is the core?
These are the main sequence temperature and spectral feature classifications of stars.
What are spectral classes?
This is the major form of energy production for a collapsing nebula before fusion begins.
What is gravitational contraction (Kelvin-Helmholtz contraction)?
This type of fusion occurs during the helium flash in a low-mass star.
What is helium fusion?
This term refers to a rapidly rotating, highly-magnetized neutron star that emits beams of electromagnetic radiation.
What is a pulsar?
This is the reason sunspots appear dark on the solar surface.
What is that sunspots are cooler than their surroundings?
This plot shows stars by temperature and luminosity.
What is the Hertzsprung-Russell (HR) diagram?
A protostar achieves hydrostatic equilibrium in this situation.
What is when internal pressure balances gravitational forces?
This is the final stage of a star like the Sun after it has evolved off the main sequence.
What is a white dwarf?
This process involves the transfer of material between a white dwarf and a companion star, leading to a less violent explosion.
What is a nova?
The solar wind is composed of these.
What are charged particles, mostly electrons and protons?
On the Hertzsprung-Russell (HR) diagram, the giants are located here.
What is the upper region of the diagram?
These are the steps involved in the formation of a star like our Sun.
What are gas cloud, fragmentation, protostar, Kelvin-Helmholtz contraction, Hayashi Track, ignition, and adjustment to main sequence?
This is how you determine the age of a star cluster using an HR diagram.
What is identifying the point where the most massive stars are turning off the main sequence and using stellar evolution models to estimate the age?
This is what causes a neutron star to become a pulsar.
What is a strong magnetic field and rapid rotation, which channels the emission of radiation into beams observed as pulses?