Answer:
<u>Geocentric Model</u>: - this model is Earth Centered
-Retrograde motion is explained by epicycles
<u>Heliocentric Model</u>: - This model is Sun Centered
-Retrograde motion is explained by the orbital speeds of planets
<u>Both models</u>:- Epicycles and deferents help explain planetary motion
-Planets move in circular orbits and with uniform motion
-The brightness of a planet increases when the planet is closest to Earth
Explanation:
Retrograde motion is an apparent change in the movement of the planet through the sky. Ptolemy's model of the solar systems was geocentric, where the Sun, Moon, planets and start all orbit the Earth in perfectly circular orbits. However this perfectly circular orbits around the Earth did not explain the occasional retrograde motion of the planets. In the Copernicus' heliocentric model, retrograde motion of planets is naturally explained. The explanation for retrograde motion in a heliocentric model is that retrograde occurs roughly when a faster moving planet catches up to and passes a slower moving planet.
Most developed countries experience a slower economic growth
compared the developing counties. Economic growth is very different from the
economic development. Development will elevate the people from the low standards
of living to proper employment which has suitable housing while growth does not
consider natural resources that will lead to pollution, diseases and
congestion. Development on the other hand is concerned with sustainability
meaning that it is meeting the needs of the present without compromising the future
needs.
Threats include:water controlintroduced species<span>development</span>
Answer:
its acually
Tokyo-Yokohama
Tokyo-Yokohama continues to be the largest city in the world, with nearly 38 million residents, according to the just released Demographia World Urban Areas (12th Annual Edition)
Answer:
World human population is expected to reach upwards of 9 billion by 2050 and then level off over the next half-century. How can the transition to a stabilizing population also be a transition to sustainability? How can science and technology help to ensure that human needs are met while the planet's environment is nurtured and restored?
Our Common Journey examines these momentous questions to draw strategic connections between scientific research, technological development, and societies' efforts to achieve environmentally sustainable improvements in human well being. The book argues that societies should approach sustainable development not as a destination but as an ongoing, adaptive learning process. Speaking to the next two generations, it proposes a strategy for using scientific and technical knowledge to better inform future action in the areas of fertility reduction, urban systems, agricultural production, energy and materials use, ecosystem restoration and biodiversity conservation, and suggests an approach for building a new research agenda for sustainability science.
Our Common Journey documents large-scale historical currents of social and environmental change and reviews methods for "what if" analysis of possible future development pathways and their implications for sustainability. The book also identifies the greatest threats to sustainability—in areas such as human settlements, agriculture, industry, and energy—and explores the most promising opportunities for circumventing or mitigating these threats. It goes on to discuss what indicators of change, from children's birth-weights to atmosphere chemistry, will be most useful in monitoring a transition to sustainability.
