velocity articles
What mathematical relationship connects the total space velocity (V) using the radial velocity ($V_r$) and tangential velocity ($V_t$)?
When measuring radial velocity ($V_r$), what spectral phenomenon indicates a star is moving toward the observer?
What essential measurement, expressed in angular units like arcseconds per year ($ ext{arcsec}/ ext{year}$), is required to define tangential velocity ($V_t$)?
What is the standard reference frame used when quoting the measured velocity of a star relative to the Milky Way?
If a star’s distance ($d$) estimate is incorrect by a factor of two, how does this error propagate into the calculated tangential velocity ($V_t$)?
What observation, related to the Doppler effect, signifies that a star has a negative radial velocity ($V_r$)?
What astrophysical insights can researchers gain by analyzing the velocity distributions of large groups of stars within the Milky Way?
How do the random motion components typically compare between ancient, halo stars and younger stars concentrated in the galactic plane?
What inherent advantage in precision does the measurement technique for radial velocity ($V_r$) offer over tangential velocity ($V_t$) determination?
What study, foundational to astrophysics, involves determining the speed and direction of stars within the Milky Way?
What physical principle allows analysis of light to determine stellar speed?
What phenomenon describes light shifting toward the redder, longer wavelengths from a distant star?
What is the formal term for the speed measured along a star's line of sight?
What causes the characteristic dark absorption lines seen in a star's spectrum?
What motion component does the Doppler measurement technique primarily fail to register on its own?
How is the transverse velocity component, or proper motion, determined?
Which theorem is utilized to combine radial velocity ($v_r$) and transverse velocity ($v_t$) for total speed?
What happens to a star's light wavelengths when it is moving toward our planet?
What is the reference frame for the radial velocity measured for a distant star?
What provides the necessary fixed reference point for measuring the fractional spectral shift?
What is Earth's approximate speed as it orbits the Sun?
What is the approximate speed of the Sun traveling around the Milky Way's core?
Approximately how long does it take the solar system to complete one full circuit around the galactic center?
What reference frame is used to measure the bulk motion of our local patch of the universe?
What is the estimated velocity of the Milky Way relative to the CMB?
The Milky Way's motion relative to the CMB is currently directed toward which specific region?
Which structure is the Milky Way part of, which is itself a member of the Virgo Supercluster?
How much faster is the Milky Way's CMB velocity compared to Earth's orbital speed?
What is scientifically remarkable about the El Gordo galaxy cluster's motion?