Explanations 
Textbooks 
Exams 
GCSE 
IGCSE 
AS 
A Level 
International A Level 
University Admissions Tests 
Flashcards 
Vaia AI 
Notes 
Study Plans 
Study Sets 
Find a job 
Find a degree 
Student Deals 
Magazine 
Mobile App Chapter 21: Problem 25
The concept of a galactic habitable zone does not consider a. the radiation field. b. the ages of stars. c. the amount of heavy elements. d. the distance of a planet from its central star.
Short Answer
Expert verified
d. the distance of a planet from its central star.
Step by step solution
01
Understand the Galactic Habitable Zone
The Galactic Habitable Zone (GHZ) is a region in a galaxy where conditions are favorable for habitable planets to exist. This concept usually includes several factors like radiation levels, the abundance of heavy elements, and the age distribution of stars.
02
Examine Each Option
Consider each provided option and check if it is a factor in the concept of the GHZ.
03
Analyze Option a
The radiation field in a galaxy can affect the habitability of planets by affecting their atmospheres and surfaces. It is generally considered in the concept of the GHZ. Thus, this option is usually considered.
04
Analyze Option b
The ages of stars are significant because older stars are more likely to have planets that have had time to develop conditions favorable for life. Therefore, the ages of stars are considered in the GHZ.
05
Analyze Option c
The amount of heavy elements, or metallicity, is crucial in planet formation. Planets need heavy elements to form from the protoplanetary disk. Thus, this factor is also considered in the GHZ.
06
Analyze Option d
The distance of a planet from its central star is a crucial factor for habitability because it determines the planet's temperature and conditions. However, this is considered more in the context of a planetary habitable zone rather than the GHZ.
07
Conclusion
Based on the analysis, the aspect that the GHZ does not consider is the distance of a planet from its central star, as this is more relevant to the specific habitable zone around individual stars rather than the galactic scale.
Unlock Step-by-Step Solutions & Ace Your Exams!
-
Full Textbook Solutions
Get detailed explanations and key concepts
-
Unlimited Al creation
Al flashcards, explanations, exams and more...
-
Ads-free access
To over 500 millions flashcards
-
Money-back guarantee
We refund you if you fail your exam.
Over 30 million students worldwide already upgrade their learning with Vaia!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Radiation Field
In the context of the Galactic Habitable Zone (GHZ), the radiation field plays a crucial role. High levels of radiation can strip away planetary atmospheres, making them uninhabitable.
This field includes various types of radiation such as ultraviolet (UV) rays, X-rays, and cosmic rays.
In regions closer to the galactic center, radiation levels are typically higher due to the presence of a large number of stars and supernovae.
Conversely, regions further away from the center may have lower radiation levels, which could be more favorable for planetary habitability.
This field includes various types of radiation such as ultraviolet (UV) rays, X-rays, and cosmic rays.
In regions closer to the galactic center, radiation levels are typically higher due to the presence of a large number of stars and supernovae.
Conversely, regions further away from the center may have lower radiation levels, which could be more favorable for planetary habitability.
Stellar Ages
Stellar ages are significant when evaluating a GHZ. Older stars are more likely to have planets that have had the necessary time to develop life.
As stars age, their radiation output typically becomes more stable, providing a more consistent environment for planets.
Moreover, older stars are less likely to experience catastrophic events like supernovae that could disrupt the habitability of nearby planets.
The distribution of stellar ages also affects the metallicity and the formation of planets, which is another key factor in determining habitability within a galaxy.
As stars age, their radiation output typically becomes more stable, providing a more consistent environment for planets.
Moreover, older stars are less likely to experience catastrophic events like supernovae that could disrupt the habitability of nearby planets.
The distribution of stellar ages also affects the metallicity and the formation of planets, which is another key factor in determining habitability within a galaxy.
Heavy Elements
The abundance of heavy elements, also known as metallicity, is essential for planet formation. Heavy elements form the building blocks of planets, including Earth-like planets.
In regions of the galaxy where heavy elements are abundant, planet formation is more likely.
These elements come from previous generations of stars that have undergone supernova explosions, dispersing these materials into space.
Therefore, the GHZ considers regions where the chemical enrichment of the interstellar medium is sufficient to support the formation of complex planetary systems.
In regions of the galaxy where heavy elements are abundant, planet formation is more likely.
These elements come from previous generations of stars that have undergone supernova explosions, dispersing these materials into space.
Therefore, the GHZ considers regions where the chemical enrichment of the interstellar medium is sufficient to support the formation of complex planetary systems.
Planetary Habitability
Planetary habitability refers to the potential of a planet to develop and sustain life. While the GHZ provides a broader context, the habitability of individual planets is determined by several factors.
The planet's distance from its central star affects its temperature and climate.
The presence of liquid water, a stable atmosphere, and a solid surface also contribute to its habitability.
It's important to note that the GHZ primarily focuses on galactic-scale factors, whereas planetary habitability zooms in on conditions around individual stars and planets.
The planet's distance from its central star affects its temperature and climate.
The presence of liquid water, a stable atmosphere, and a solid surface also contribute to its habitability.
It's important to note that the GHZ primarily focuses on galactic-scale factors, whereas planetary habitability zooms in on conditions around individual stars and planets.
