Star FAQs:


Q: Is a star a luminous sphere of plasma held together by its own gravity?

A: Yes.

Q: Were stars permanently affixed to a heavenly sphere and that they were immutable?

A: Yes.

Q: Is a star determined by its radius and surface temperature?

A: Yes.

Q: Are stars those that undergo a dramatic change in their properties?

A: Yes.

Q: Are stars thought to be rare?

A: Yes.

Q: Are stars observed to be members of binary star systems?

A: Yes, and the properties of those binaries are the result of the conditions in which they formed.

Q: Is a star determined by the rate of energy production of its core and by its radius?

A: Yes, and is often estimated from the star's color index.

Q: Are stars greater than the current age of the universe?

A: Yes, and no stars under about 0.85 M☉ are expected to have moved off the main sequence.

Q: Are stars so dim that their light is as bright as a birthday candle on the Moon when viewed from the Earth?

A: Yes.

Q: Is a star cooler than the core?

A: Yes.

Q: Is a star the main factor that determines its evolution and eventual fate?

A: Yes.

Q: Were stars also given names?

A: Yes, and particularly with Arabic or Latin designations.

Q: Were stars equally distributed in every direction?

A: Yes, and an idea prompted by the theologian Richard Bentley.

Q: Is a star at least 5,000,000 times more luminous than the Su?

A: Yes, and t least 5,000,000 times more luminous than the Sun.

Q: Are stars generally referred to as being spheres of plasma?

A: Yes.

Q: Are stars likely to have existed in the very early universe?

A: Yes, and may have started the production of chemical elements heavier than hydrogen that are needed for the later formation of planets and life.

Q: Were stars like the Sun?

A: Yes, and may have other planets, possibly even Earth-like, in orbit around them, an idea that had been suggested earlier by the ancient Greek philosophers, Democritus and Epicurus, and by medieval Islamic cosmologists such as Fakhr al-Din al-Razi.

Q: Are stars often surrounded by a protoplanetary disk and powered mainly by the conversion of gravitational energy?

A: Yes.

Q: Are stars longer than the age of the universe?

A: Yes, and no such star has yet reached the white dwarf stage.

Q: Are stars much too small in angular size to be observed with current ground-based optical telescopes?

A: Yes, and so interferometer telescopes are required to produce images of these objects.

Q: Are stars red dwarfs?

A: Yes, and most stars in the Milky Way are likely single from birth.

Q: Are stars visible to the naked eye from Earth during the night?

A: Yes, and appearing as a multitude of fixed luminous points in the sky due to their immense distance from Earth.

Q: Are stars given a single-letter classification according to their spectra?

A: Yes, and ranging from type O, which are very hot, to M, which are so cool that molecules may form in their atmospheres.

Q: Are stars believed to be part of multiple-star systems?

A: Yes.

Q: Is a star the amount of light and other forms of radiant energy it radiates per unit of time?

A: Yes.

Q: Is a star expressed in terms of its apparent magnitude?

A: Yes.

Q: Is a star in a state of hydrostatic equilibrium: the forces on any small volume almost exactly counterbalance each other?

A: Yes.

Q: Are stars not spread uniformly across the universe?

A: Yes, but are normally grouped into galaxies along with interstellar gas and dust.

Q: Are stars between 1 billion and 10 billion years old?

A: Yes.

Q: Are stars also found?

A: Yes.

Q: Were stars made primarily of hydrogen and helium in her 1925 PhD thesis?

A: Yes.

Q: Were stars further understood through advances in quantum physics?

A: Yes.

Q: Is a star generated within regions of the interior where convective circulation occurs?

A: Yes.

Q: Is a star determined by its initial mass?

A: Yes, and including such characteristics as luminosity, size, evolution, lifespan, and its eventual fate.

Q: Is a star at least on the order of 107 K?

A: Yes, The resulting temperature and pressure at the hydrogen-burning core of a main sequence star are sufficient for nuclear fusion to occur and for sufficient energy to be produced to prevent further collapse of the star.

Q: Is a star several million kelvins?

A: Yes.

Q: Were stars classified from A to Q based on the strength of the hydrogen line?

A: Yes.

Q: Were stars grouped into constellations and asterisms?

A: Yes, and the brightest of which gained proper names.

Q: Are stars said to be on the main sequence?

A: Yes, and are called dwarf stars.

Q: Is a star found?

A: Yes, such as by measuring the parallax, then the luminosity of the star can be derived.

Q: Are stars through occultation?

A: Yes.

Q: Was a star formed?

A: Yes.

Q: Is a star manifested as the stellar wind?

A: Yes, and which streams from the outer layers as electrically charged protons and alpha and beta particles.