The densely packed neutrons of a neutron star cannot balance the inward pull of gravity if the total mass is
A) greater than Schwartzschild's limit of 3 solar masses.
B) less than 1.0 solar masses.
C) Chandrasekhar's limit of 1.4 solar masses.
D) not at least 25 solar masses.
E) between 1.4 and 2.0 solar masses.
Question 2
According to our present theory of solar system formation, which of the following statements about the growth of terrestrial and jovian planets is not true?
A) Both types of planet begun with planetesimals growing through the process of accretion, but only the jovian planets were able to capture hydrogen and helium gas from the solar nebula.
B) Swirling disks of gas, like the solar nebula in miniature, formed around the growing jovian planets but not around the growing terrestrial planets.
C) The jovian planets began from planetesimals made only of ice, while the terrestrial planets began from planetesimals made only of rock and metal.
D) The terrestrial planets formed inside the frost line of the solar nebula and the jovian planets formed beyond it.
Population predictions for 2000–2050, using three different total fertility rates (
Artist's conception of the birth of a star within a dense molecular cloud.
The Sun is the nearest star to Earth.
The reflection nebula NGC 1999 is brilliantly illuminated by V380 Orionis (center), a variable star
Star Map Eastern Horizon
To keep the foot under the center of gravity, the biped’s femur is angled from hip to knee. The quad