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From gas to stars over cosmic time
1Department of Astrophysics, American Museum of Natural History, 79th Street at Central Park West, New York, NY 10024, USA. mordecai@amnh.org
Science (New York, N.Y.)
|July 2, 2013
Summary
The universe's star formation rate density peaked 10 billion years ago, exceeding present levels tenfold. Understanding this dynamic cosmic history requires advanced observations and simulations to model stellar feedback accurately.
Area of Science:
- Cosmic star formation history
- Astrophysics
- Galaxy evolution
Background:
- Star formation has evolved dynamically since the universe's inception.
- The star-formation rate density peaked approximately 10 billion years ago, significantly higher than today's rate.
- Early star formation rise is poorly constrained by current observations.
Purpose of the Study:
- To investigate the dynamic history of cosmic star formation.
- To address challenges in theoretical modeling of star formation, particularly stellar feedback.
- To outline the expected contributions of next-generation observational and simulation tools.
Main Methods:
- Analysis of observational data from ground and space-based instruments.
- Theoretical modeling incorporating stellar radiation and supernova feedback.
- Comparison of simulation predictions with observational constraints.
Main Results:
- Identified a dramatic increase in star-formation rate density, peaking 10 billion years ago.
- Highlighted difficulties in observing and modeling the initial rise of star formation.
- Noted challenges in simulating the impact of stellar feedback on subsequent star formation.
Conclusions:
- Future observations and advanced simulations are crucial for a comprehensive understanding of star formation history.
- Next-generation instruments are expected to reveal the complete cosmic star formation timeline.
- Simulations are becoming capable of accurately predicting observed star formation histories.
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