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Afelion and perihelion. Intoduction. The orbits of some planets are almost perfect circles, but others are not. Some orbits are shaped more like ovals. Scientists call these oval shapes "ellipses“. - PowerPoint PPT Presentation
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AFELION AND PERIHELION
Intoduction The orbits of some planets are almost
perfect circles, but others are not. Some orbits are shaped more like ovals.
Scientists call these oval shapes "ellipses“.
Since the Sun is not at the center of an elliptical orbit, the planet moves closer towards and further away from the Sun as it orbits.
Introduction The place where the planet is closest to the
Sun is called perihelion When the planet is furthest away
from the Sun, it is at aphelion. The words "aphelion" and
"perihelion" come from the Greek language.
In Greek, "helios" mean Sun,"peri" means near, and "apo" means away from.
How to find Distance? If you want to find distance, you must
know Eccentricity of an Orbit, Semi-major axis, Sun’s diameters when she is in
perihelion and aphelion.
Formulas You will need these formulas:
Where a is the mean distance to the Sun,
e the eccentricity of an ellipse. da – Sun’s diameter in aphelion dp –Sun’s diameter in perihelion. aA - distance in aphelion. ap - distance in perihelion.
Targets To find distance from Earth to Sun. To find the eccentricity. To compare sun‘s diameters in photos. To compare rezults. To find out, why is cold in winter.
?
Hypothesis I think, that distance in perihelion
and afelion will be very close to Semi-major axis.
Work progres I found 2 Sun pictures , when she is in
aphelion and perihelion.
I gauged sun’s diameters.da=7,9cmdp =8,15cm
I found
I found how many persent differentiate sun diameters in aphelion and perihelion.
I found the eccentricity.
I found aA and ad
For the Earth a = 149,600,000 km Aphelion:
Perihelion:
Why is cold in winter? I found out why is cold in winter. Earth
reaches perihelion, its closest approach to the Sun and when you might think it should be warmest, in January - the middle of winter in the Northern Hemisphere! The difference in distance is not the cause of our seasons. Instead, seasons are caused by the tilt of Earth's axis.
Results Name Real size My size
Perihelion 147 098 074 km 147 264 159 kmAphelion 152 097 701 km 151 931 614 kmEccentricity 0,016 710 219 0,0156
Inference My Hypothesis had reasserted. Now I know what’s mean eccentricity,
perihelion and aphelion. I know how to find eccentricity, perihelion
and aphelion. I know why in summer are warm and why in
winter are cold. If you want to fly in the Sun, you must fly in
winter, because distance is the shortest in winter.
Thanks