A supernova is a powerful explosion that occurs when a massive star reaches the end of its life. During this explosion, the star's core collapses and releases a tremendous amount of energy, causing the star to briefly outshine an entire galaxy.

Supernovae are classified into two main types based on their spectral features and the presence or absence of hydrogen in their ejecta. Type Ia supernovae result from the thermonuclear explosion of a white dwarf, while Type II supernovae occur when a massive star collapses under its own gravity.

The Hubble Space Telescope is a powerful tool for studying supernovae. It allows astronomers to observe supernovae in distant galaxies, measure their properties, and gain insights into the evolution of stars and the universe.

The Hubble Ultra Deep Field image, taken in 2004, revealed a vast collection of galaxies, including many that were undergoing supernova explosions. This image provided evidence for the existence of a supernova factory, a region where supernovae occur frequently.

The Hubble Space Telescope measures the expansion rate of the universe by observing the redshift of distant galaxies. As the universe expands, the light from distant galaxies is stretched, causing their spectral lines to shift towards longer wavelengths (redder colors). By measuring the amount of redshift, astronomers can determine the distance to the galaxies and calculate the expansion rate of the universe.

SN 1987A was a Type II supernova that occurred in the Large Magellanic Cloud, a satellite galaxy of the Milky Way. It was the closest supernova observed in modern history and was extensively studied by the Hubble Space Telescope and other telescopes.

The Hubble Deep Field image, taken in 1995, provided the first direct evidence for the existence of dark energy. By measuring the distances to distant galaxies and comparing them to their expected distances based on the expansion rate of the universe, astronomers found that the universe is expanding at an accelerating rate. This acceleration is attributed to the presence of dark energy, a mysterious force that is causing the expansion of the universe to accelerate.

The Hubble Space Telescope observes the light emitted by supernovae to study their chemical composition. By analyzing the spectral lines in the light, astronomers can identify the elements present in the supernova ejecta. This information provides insights into the nucleosynthesis processes that occur during supernova explosions and the origin of the elements in the universe.

The Supernova Legacy Survey is a Hubble Space Telescope mission dedicated to studying supernovae. The survey aims to obtain high-quality observations of a large number of supernovae in order to better understand their properties, evolution, and role in the universe.

The Hubble Space Telescope helps astronomers study the evolution of galaxies by observing the motion of stars in nearby galaxies. By measuring the velocities of stars, astronomers can infer the mass and structure of galaxies and gain insights into their formation and evolution.

The Hubble Space Telescope Treasury Program revealed the existence of a black hole at the center of our galaxy, known as Sagittarius A*. By observing the motion of stars near the center of the galaxy, astronomers were able to infer the presence of a massive black hole.

The Galaxy Evolution Survey is a Hubble Space Telescope mission dedicated to studying the formation and evolution of galaxies. The survey aims to obtain high-quality observations of a large number of galaxies in order to better understand their properties, evolution, and role in the universe.

The Hubble Space Telescope observes the cosmic microwave background radiation, the leftover radiation from the Big Bang, to study the early universe. By measuring the temperature and polarization of the cosmic microwave background radiation, astronomers can gain insights into the conditions and properties of the universe shortly after its birth.

The Hubble Space Telescope Treasury Program revealed the existence of a water vapor plume on Jupiter's moon Europa. By observing Europa in the ultraviolet and infrared wavelengths, astronomers were able to detect the presence of water vapor, suggesting the existence of a subsurface ocean on Europa.

The Exoplanet Atmosphere Survey is a Hubble Space Telescope mission dedicated to studying the atmospheres of planets outside our solar system. The survey aims to obtain high-quality observations of a large number of exoplanets in order to better understand their atmospheric composition, structure, and evolution.