Summarize the key information about the characteristics and classification of stars presented in the following passage:

Stars are the fundamental building blocks of galaxies and are among the most fascinating objects in the universe. These luminous celestial bodies are massive spheres of hot, ionized gas that generate energy through nuclear fusion reactions in their cores.

Stars can be classified based on their characteristics, such as temperature, luminosity, and composition. One of the most widely used classification systems is the Harvard Spectral Classification, which groups stars into seven main spectral types: O, B, A, F, G, K, and M, arranged in decreasing order of surface temperature.

O and B-type stars are the hottest and most massive, ranging from blue to blue-white in color. These stars have short lifespans and are often found in young star clusters and regions of active star formation. A-type stars are white or bluish-white and are among the brightest stars visible in the night sky.

F, G, and K-type stars are cooler and more stable, with surface temperatures ranging from white to yellow and orange. Our Sun is a G-type star, often referred to as a yellow dwarf. M-type stars are the coolest and smallest, appearing reddish in color and having relatively low luminosities.

Another important characteristic used in star classification is luminosity, which is a measure of the total amount of energy a star emits. Based on their luminosity, stars can be classified as dwarfs, giants, or supergiants. Dwarfs are smaller, less luminous stars like our Sun, while giants and supergiants are larger, more luminous stars that have exhausted their core hydrogen fuel and expanded in size.

Stars can also be classified based on their composition, with the majority being composed primarily of hydrogen and helium, while some may have higher concentrations of heavier elements like carbon, oxygen, and nitrogen.
Summarize the key information about the characteristics and classification of stars presented in the following passage:

Stars are the fundamental building blocks of galaxies and are among the most fascinating objects in the universe. These luminous celestial bodies are massive spheres of hot, ionized gas that generate energy through nuclear fusion reactions in their cores.

Stars can be classified based on their characteristics, such as temperature, luminosity, and composition. One of the most widely used classification systems is the Harvard Spectral Classification, which groups stars into seven main spectral types: O, B, A, F, G, K, and M, arranged in decreasing order of surface temperature.

O and B-type stars are the hottest and most massive, ranging from blue to blue-white in color. These stars have short lifespans and are often found in young star clusters and regions of active star formation. A-type stars are white or bluish-white and are among the brightest stars visible in the night sky.

F, G, and K-type stars are cooler and more stable, with surface temperatures ranging from white to yellow and orange. Our Sun is a G-type star, often referred to as a yellow dwarf. M-type stars are the coolest and smallest, appearing reddish in color and having relatively low luminosities.

Another important characteristic used in star classification is luminosity, which is a measure of the total amount of energy a star emits. Based on their luminosity, stars can be classified as dwarfs, giants, or supergiants. Dwarfs are smaller, less luminous stars like our Sun, while giants and supergiants are larger, more luminous stars that have exhausted their core hydrogen fuel and expanded in size.

Stars can also be classified based on their composition, with the majority being composed primarily of hydrogen and helium, while some may have higher concentrations of heavier elements like carbon, oxygen, and nitrogen.
user
The passage provides a comprehensive overview of the characteristics and classification of stars. It introduces stars as the fundamental building blocks of galaxies, describing them as massive spheres of hot, ionized gas that generate energy through nuclear fusion reactions in their cores.

The passage then outlines the Harvard Spectral Classification system, which groups stars into seven main spectral types (O, B, A, F, G, K, and M) based on their surface temperature, ranging from the hottest and most massive O and B-type stars to the coolest and smallest M-type stars.

It also discusses the classification of stars based on their luminosity, dividing them into dwarfs (smaller, less luminous stars like our Sun), giants, and supergiants (larger, more luminous stars that have exhausted their core hydrogen fuel and expanded in size).

Additionally, the passage mentions that stars can be classified based on their composition, with most being composed primarily of hydrogen and helium, while some may have higher concentrations of heavier elements like carbon, oxygen, and nitrogen.

The summary covers the key characteristics used to classify stars, including temperature, luminosity, and composition, providing examples and explanations for each classification system.
assistant
Generate a series of (instruction, response) pairs that are similar in context and structure to the example provided below. Each pair should consist of a concise instruction followed by an appropriate, detailed response. The instruction should pose a clear task or question, while the response should provide a comprehensive answer or solution that could be understood by someone with a basic understanding of the subject.

Example pair: 
Instruction: Please write a summary, in simple language, of who Daisy Eagan is using the following:

Throughout her multi-decade career, Tony award-winner Daisy Eagan has dazzled audiences from the stage to television and film, and with her writing. Next stop – time to take over the podcast world.
 
At age eleven, Eagan became the youngest actress to win a Tony Award for Best Performance by A Featured Actress for playing Mary Lennox in “The Secret Garden.” In 2016, Eagan returned to “The Secret Garden” to play Martha for the 25th anniversary concert production at Lincoln Center and at the Shakespeare Theatre in Washington, DC. Eagan also appeared on Broadway in “Les Miserables” and “James Joyce's The Dead,” and most recently on stage she starred in the First National Tour of Stephen Karam’s Tony-winning play, “The Humans.”
 
On television, Eagan can be seen on Freeform’s critically-acclaimed series “Good Trouble.” Additional television credits include HULU’s “The Path,” HBO’s “Girls,” CBS’ “The Mentalist,” “Without a Trace,” “Ghost Whisperer,” “The Unit” and “Numb3rs.”
 
A published award-winning writer with a loyal and growing audience, Eagan is a fierce fighter and activist for women's and LGBTQ rights. She is a rousing voice in political arenas and continues to fight for change throughout her literary career. She has written op-eds for publications including HuffPost and Playbill.com and had a column for USA Today Network’s The Journal News.
Response: Daisy Eagan is an award-winning stage and television actress, writer, and activist, and now can add podcaster to her list of roles. At only 11 years old, she won a Tony Award, she was the youngest actress to win such a prestigious award. She has appeared in several TV series, including The Path, Girls, and The Mentalist. Eagan is also an award-winning writer, activist, and a rousing voice in politics. 

Your task is to generate more pairs that maintain this level of clarity and detail. The topic is Summarization. Write a long text of instruction by yourself, then summarize the given instruction in a response. Ensure that the responses are informative and accurate, suitable for an educational context. 

Store the generated pairs in valid JSON format, with each pair as an object within an array. Each object should have two key-value pairs: "instruction" and "response". For instance: 

{"contents": [{"instruction": "text", "response": "text"}, {"instruction": "text", "response": "text"}, ...]} 

Remember to maintain consistency in the format and ensure the generated pairs are diverse and cover a broad range of subjects. You must return the response in the asked format and you must not add any additional text in your response.
