Mixed Deck — All ASP Topics Flashcards

What are gravitational waves?

Answer: Ripples in spacetime generated by accelerating massive objects, as predicted by general relativity

Gravitational waves are propagating distortions (ripples) in the fabric of spacetime generated by accelerating massive objects such as merging black holes or neutron stars, traveling at the speed of light.

What is the Hertzsprung-Russell diagram primarily used to show?

Answer: The relationship between stellar luminosity and temperature

The H-R diagram plots stars by their luminosity versus surface temperature, revealing distinct groups like the main sequence and giant branches.

What is the difference between a meteor, meteoroid, and meteorite?

Answer: Meteoroid is in space, meteor is in Earth's atmosphere, meteorite reaches the ground

A meteoroid is a small rocky body in space, a meteor is the visible streak of light when it enters Earth's atmosphere, and a meteorite is any portion that survives to reach Earth's surface.

What is the advantage of space-based telescopes over ground-based ones?

Answer: Space telescopes avoid atmospheric absorption and blurring, enabling diffraction-limited observations across all wavelengths

Space telescopes operate above Earth's atmosphere, which absorbs UV, X-ray, gamma-ray, and some infrared wavelengths, and causes optical blurring (seeing); space telescopes achieve diffraction-limited performance across the full spectrum.

What is the Doppler effect and how is it used in astronomy?

Answer: The change in observed frequency of waves from a moving source; used to measure radial velocities of celestial objects

The Doppler effect is the change in observed frequency or wavelength of waves emitted by a moving source; in astronomy, spectral line shifts reveal radial velocities of stars, galaxies, and gas clouds.

What is the Chandrasekhar limit in stellar astrophysics?

Answer: The maximum mass of a white dwarf (~1.4 solar masses)

The Chandrasekhar limit (~1.4 solar masses) is the maximum mass a white dwarf can have before electron degeneracy pressure can no longer support it.

What is the Fermi Gamma-ray Space Telescope's primary contribution?

Answer: It mapped the gamma-ray sky, discovering gamma-ray bursts, pulsars, blazars, and the Fermi bubbles above and below the Milky Way

The Fermi Gamma-ray Space Telescope has produced the most comprehensive gamma-ray sky map, detecting thousands of sources and discovering giant gamma-ray-emitting bubbles (Fermi bubbles) extending 25,000 light-years above and below the galactic center.

What is a galaxy cluster?

Answer: A collection of hundreds to thousands of galaxies bound together by gravity, the largest gravitationally bound structures in the universe

Galaxy clusters are the largest gravitationally bound structures in the universe, containing hundreds to thousands of galaxies plus hot intracluster gas and dark matter, spanning millions of light-years.

What is the habitable zone (Goldilocks zone) around a star?

Answer: The orbital range where liquid water could exist on a planet's surface given sufficient atmospheric pressure

The habitable zone is the orbital distance range around a star where a planet with sufficient atmospheric pressure could maintain liquid water on its surface—considered essential for life as we know it.

What is the significance of the 51 Pegasi b discovery in 1995?

Answer: It was the first confirmed exoplanet found orbiting a sun-like star, a 'hot Jupiter'

51 Pegasi b, discovered by Mayor and Queloz using the radial velocity method, was the first confirmed exoplanet orbiting a sun-like star, revealing an unexpected 'hot Jupiter' class of giant planets orbiting extremely close to their host stars.

What is the significance of the Chandrayaan and Artemis programs for lunar exploration?

Answer: They represent renewed international efforts to explore and characterize the Moon, including searching for water ice at the lunar poles for potential human missions

India's Chandrayaan missions and NASA's Artemis program represent a renewed global focus on the Moon, targeting polar water ice deposits, geological exploration, and ultimately returning humans to the lunar surface for sustained exploration.

What is a neutron star?

Answer: An ultra-dense stellar remnant composed mainly of neutrons

A neutron star is an extremely dense stellar remnant formed from the collapsed core of a massive star after a supernova, with densities so extreme that protons and electrons merge into neutrons.

Community of astronomy clubs engaging the public with telescopes.

Answer: NASA Night Sky Network

The NASA Night Sky Network is a nationwide consortium of astronomy clubs that partners with NASA to engage the public in astronomy. These clubs frequently host public stargazing events and educational programs, often utilizing telescopes, making it a direct fit for the description of a community engaging the public with telescopes.

What is the magnitude scale in astronomy?

Answer: A logarithmic scale of stellar brightness where lower numbers indicate brighter objects

The magnitude scale is a logarithmic measure of brightness where each step of 1 magnitude corresponds to a brightness ratio of ~2.512, with lower (and negative) numbers indicating brighter objects.

The celestial coordinate equivalent of longitude on Earth is called:

Answer: Right ascension

Right ascension is the celestial equivalent of geographic longitude, measured in hours eastward from the vernal equinox.

Members receive Society publications without charge

Answer: Publication Access

'Publication Access' refers to a common benefit offered to members of a society, allowing them to receive the organization's journals, newsletters, or other published materials without incurring additional charges. This perk ensures members stay informed about the society's activities and advancements in the field.

Which spacecraft first provided detailed images of Pluto's surface in 2015?

Answer: New Horizons

NASA's New Horizons spacecraft made its historic flyby of Pluto on July 14, 2015, returning the first close-up images of the dwarf planet's surface.

What is the Andromeda Galaxy (M31) and what is its fate relative to the Milky Way?

Answer: The nearest large spiral galaxy; it is on a collision course with the Milky Way in about 4.5 billion years

The Andromeda Galaxy is the nearest large spiral galaxy at about 2.5 million light-years and is gravitationally bound to the Milky Way, with simulations predicting a merger in approximately 4.5 billion years.

What is Hubble's Law?

Answer: The relationship showing that galaxies recede from us at a velocity proportional to their distance

Hubble's Law states that distant galaxies recede from us with velocities proportional to their distances (v = H₀ × d), providing evidence for the expanding universe.

Series of over 400 volumes of professional astronomy conference proceedings

Answer: Astronomical Society of the Pacific Conference Series (ASPCS)

The Astronomical Society of the Pacific Conference Series (ASPCS) is a well-established publication series that compiles the proceedings from numerous professional astronomy conferences. With over 400 volumes, it serves as a significant repository for research and discussions within the astronomical community.