Transcript 6.4 What can you see?

7 April 2016
6.4 What can you see?
A man and his son were in
a car crash. The father died,
but the son was critically
injured and rushed to
hospital. When he reached
the operating table, the
doctor on duty looked at
him and said ‘Oh goodness,
it's my son!’ How can this
be?
Lesson
Learning outcomes
6.2
I can look up data in tables. (Level 4)
6.2
I can explain that there is no friction in Space. (Level 4)
6.2
I can remember that gravity holds planets in orbit around the Sun, and the Moon
and satellites in orbit around the Earth. (Level 4)
6.3
I can describe the uses of some satellites. (Level 4)
6.4
I can describe how models of the Solar System have changed over time. (Level 4)
6.4
I can describe the current model of the Solar System. (Level 4)
6.5
I can describe weight as a force. (Level 4)
6.6
I can explain how scientists use models to describe things (Level 4)
6.2
I can explain how to improve the accuracy of experiments. (Level 5)
6.2
I can explain how friction affects the motion of objects. (Level 5)
6.2
I can explain how to take measurements accurately. (Level 5)
6.3
I can explain the difference between natural and artificial satellites. (Level 5)
6.4
I can explain why the Sun seems to move across the sky. (Level 5)
6.5
I can calculate weight from mass. (Level 5)
6.6
I can describe the motion of objects under simple conditions. (Level 5)
6.3
I can relate the properties of a satellite to its use. (Level 6)
6.4
I can relate observations in history to Solar System models. (Level 6)
6.5
6.2
6.3
I can describe the use of gravity meters to explore underground. (Level 6)
I can explain the link between the gravitational attraction of an object and force and
distance. (Level 7)
I can describe the way that gravitational attraction causes satellites to orbit. (Level 7)
6.5
I can explain how a gravity meter works. (Level 7)
6.6
I can describe the motion and gravitational affects of spacecraft visiting the Moon from
Earth. (Level 7)
6.2
I can discuss Cavendish’s experiment in detail. (Level 8)
6.3
I can describe the relationship between orbital speed, distance and gravitational
attraction. (Level 8)
I can describe the relationship between planet size, distance from Sun and surface
conditions.(Level 8)
6.3
6.6
I can explain the limitations and uses of a variety of models. (Level 8)
Before
Learned
Revised
Did the Universe always exist?
Learn about
• Different models of the Solar System and
how beliefs influenced them
• How evidence from observations helps
improve models
• How scientists get evidence about the
Universe now
Explaining the Universe
• For thousands of years people have used
their observations and beliefs to explain
the movements they see in the night sky
• In 550 BCE Pythagoras believed that
everything was made of four materials
(elements) with fire being the most
important
• His model had fire at the centre of the
Universe with everything (including the
Sun) moving around it
Explaining the Universe
• One hundred years later Plato observed
that from the Earth we see the Sun and
planets apprarently moving around us
• He came up with a geocentric model
• Aristotle was Plato’s pupil, in his model
stars and planets were attached to 56
‘celestial spheres’ which surround the
Earth
Making observations
• In around 100 CE, Ptolemy observed that
some planets seem to do a slow loop-theloop as they move across the sky
• He used Aristotle’s model and added a
small sphere to each celestial sphere to
that each planet performed a loop during
its circuit
• Ptolemy’s model was accepted for
thousands of years as it explained
observations and fitted with their religious
Making observations
• In the sixteenth century, Copernicus spent 30
years observing the night sky. He devised the
heliocentric model of the solar system which
had the sun at the centre
• In 1609 Galileo invented the telescope and more
observation could then be made
• A few decades later Kepler used Brahe’s
observations to make the heliocentric model
better by working out that planets move in
elliptical orbits
Astronomy today
• Using telescopes and space exploration,
astronomer have gathered more evidence
to support Keplers heliocentric model
• This has led to the discovery of hundreds
of other planets going around other stars
• In observing the Universe, scientists have
discovered other galaxies so more
models have been constructed to explain
these observation
Questions 4-6
• Scientists now believe that it is gravity that
holds planets in their orbit. In Aristotles
model what kept planets in their place? (4)
• Why did Ptolemy say his model was better
than Aristotle’s? (5)
• Do you think that the belief that heaven is
located around the Earth is a belief that
began during the time of the heliocentric or
geocentric model? (6)
Questions 7-8
• The idea of galaxies as clusters of billions
of stars doesn’t feature in early models of
the Universe. Use this as an examples to
show the link between observations and
models. (7)
• If a star has a massive planet nearby, the
planet can be detected by a wobble in the
stars light as the planet moves around and
pulls the star. Why is it harder to detect a
small planet orbiting the same star? (8)
Orbits
• The Earth moves around the Sun in its
orbit
• The length of the time it takes to do this is
called a year
• This takes about 365.24 days so every
four years we have a leap year
• Mr Porter was born on this extra day
The Moon
• A satellite is something that goes around a
planet (not really)
• The Moon is a natural satellite of the Eart
but we also have many man-made
satellites
• It takes about 28 days for the Moon to go
round the Earth, this is a Month (from
Moon)
This was first proposed
by______________. It drew on
Galileo’s and Copernicus’ claim
that_________________________.
Newton believed that it was
____________________________. It
required the understanding that
____________________________
This was first proposed by…
(Newton). It drew on Galileo’s claim
that…(the Earth orbits the Sun).
Newton believed that it was
(natural forces not gods that lead
to planetary motion). It required
the understanding that…
(gravitational forces act through
space, the Earth is a sphere).