What Ionizes the Gas in a Planetary Nebula (See the Image

question 35

Multiple Choice

What ionizes the gas in a planetary nebula (see the image below) and makes it visible?

• A) X-ray photons emitted by a pulsar
• B) ultraviolet photons emitted by a white dwarf
• C) the shock wave from a supernova
• D) hydrogen burning in the nebular gas

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Definitions:

Disturbing the Peace

A criminal offense involving acts that disrupt the public order, such as excessive noise or violent behavior in a public place.

Convicted

Found guilty of a crime following a trial or through a guilty plea in a court of law.

Felony

A serious crime, typically one involving violence, regarded more severely than a misdemeanor, and usually punishable by imprisonment for more than one year or by death.

Misdemeanor

A criminal offense that is less severe than a felony, typically punishable by fines or incarceration for less than one year.