You Are Examining Quasars and You Happen Upon Two Quasars

question 16

Multiple Choice

You are examining quasars and you happen upon two quasars in the same part of the sky that have identical spectra.You cannot see any massive object in the region between the two quasars.What is a reasonable explanation for this discovery?

• A) The discovery is not really a surprise because all quasars are formed by the same processes and all have virtually identical spectra.
• B) The two quasars are part of a binary pair of quasars that were formed together, are at the same stage in their lives, and have the same spectra.
• C) The two quasars cannot be gravitational lensing images because there is no visible lensing object in the space between them.
• D) The two quasars are most likely gravitational lensing images, and the lensing object is mostly dark matter with little visible emission.

---

Definitions:

Point

A specific location in space defined by coordinates on a graph or plane, often represented as an ordered pair (x, y).

General Form

A standard way of writing something, in mathematics, typically referring to the standard form of an equation.

Points

Refers to specific positions or locations in a geometric space, each defined by coordinates.

Line

An infinitely extending one-dimensional entity without any thickness, known as a line.