GRADING for Essay # 3
Solar Phenomena
50 points total
Read through the essay once before grading…
5 points
Identification – Name, Date, Period, Title
-
5 points
Mechanics
-
10 points
Up to -3 points if they severely limit your ability to read the papers. Do not attempt to mark
all of the errors…
Introduction
-
25 points
1 point if any one of the 4 missing.
Must make a claim… which solar events (radiation, sunspots/solar flares, life cycle) pose a
threat to us in your lifetime?
Must cite some reasons for their claim (general)
Supporting / Informational Paragraphs
-
Must have information about radiation [Activity 5]
1. Must address ultraviolet – the biggest threat??? – comes from nuclear fusion / sun –
high energy, low wavelength EM radiation, reaches Earth, some blocked by ozone
layer – but ozone layer is being depleted… more reaches us now than in past and
likely even more will reach us in the future… causes skin damage… may lead to skin
cancer – we can protect ourselves… sunglasses, sunscreen, limit exposure
2. May address other harmful radiation
 Gamma rays and X-rays – blocked by our atmosphere – dangerous to
astronauts and frequent airplane users – particularly supersonic airplanes –
 Other radiation is not harmful – radiowaves, microwaves, infrared rays,
visible light… and can – in fact be helpful… [POSSIBLE EXTRA CREDIT]
3. Radiation is an ongoing concern to us… particularly UV radiation…
-
Must have information about sunspots / solar flares [Activity 5]
1. sunspots – small dark areas on sun’s visible surface – look dark because they are
cooler (~ 1500 K cooler) than surrounding area – highly magnetic - caused by
magnetic field lines just below the Sun’s surface that are twisted and poke through
the solar photosphere – last for a few hours to a few months – appear to move
because the Sun is actually rotating on its own axis – Number of Sunspots vary over
a 10-11 year cycle.
2. solar flare – blasts from the sun that release enormous amounts of UV, X-ray, and
radiowaves as well as protons and electrons; can intensify the solar winds…
3. Both sunspots and solar flares cause disturbances here on earth… (OK to associate
these mainly with solar flares…)… high radiation events can disturb Earth-orbiting
satellites and astronauts – can create electric currents that cause power surges that
-
knock out power grids – can disrupt telecommunications traffic – interrupt cell
phone reception; can intensify solar winds which can lead to radio signal
interference; can intensify solar weather which is a hazard to astronauts and people
aboard high-flying aircraft – especially that in the polar regions. Can also cause the
auroras – which are beautiful, colorful displays.
4. Solar flares (sunspots) are a continued concern to us… particularly as our
dependence on energy and telecommunications expands. Perhaps we will be able to
develop something to prevent the hazards to our lifestyle?
Must have information about life cycle [Activity 7]
1. all stars start in a molecular cloud – a cloud of gas and dust (nebula)
2. material in cloud is drawn together by gravity… starts mixing / swirling / - forms a
disc with a central hub (core) that starts to heat up – this is called a protostar… these
events happen in places called stellar nurseries… star births can sometimes be
started from the collision of 2 galaxies… or from nearby supernovas…
3. when the temp is high enough in the core (15 million K) nuclear fusion starts…
hydrogen atoms fuse together to make helium…a star is born… these are often very
beautiful areas in space… as there is lots of UV radiation being given off… which
vaporizes the cloud and makes beautiful shapes in space…
4. the outward force from fusion balances the inward force of gravity… and the star is
now a main sequence star… many stars will spend 90% of its life on the main
sequence…
5. our star – the Sun is currently a middle aged yellow star on the main sequence. It is
about 4.6 billion years old and is expected to live about 10 billion years.
6. As stars age, the lose mass in the form of a stellar wind…
7. The end of a star depends on its mass…
 stars that are in the lower mass (like our sun) will end up forming a white
dwarf – the white dwarf is often surrounded by beautiful shells of gas and
dust… and are described as a planetary nebulae
 the Sun and other stars its size and smaller actually runs out of
hydrogen… collapses… starts fusing helium… expands to form a red
giant… runs out of helium… collapses to form a white dwarf.
 stars that are more massive will end up forming a neutron star or black hole.
 more massive stars also run out of hydrogen… collapses… starts
fusing helium… expands to form a super red giant… runs out of
helium… collapses … starts fusing bigger atoms – explodes in a
supernova…. then stops fusing when iron is formed… collapses to
form a very dense neutron star… even more massive stars end in a
black hole…
8. Is there a threat here? Unlikely – the Sun is expected to last for another 5 billion
years. If we were near a supernova, we would experience strong radiation and shock
waves from the explosion. However there are no stars near enough to us that are
near their end time either…
5 points
Conclusion
-
Must restate claim… which solar events/phenomena pose a threat to us in our lifetime….
Must cite some reasons for their claim (general)
OTHER GRADING NOTES:
Flexibility – It is OK for students to make different claims – no absolutely right /wrong answer….
Students won’t have every specific fact listed… just need some – hopefully compelling ….
Don’t get hung up on grammar, etc.
Need paragraphs … ok to have different organization
Writing Organizer for Chapter Challenge
Essay 3 – Solar Influences
Write on a different sheet of paper! You will turn these notes in for points.
Solar Influences - Describe the kinds of solar activities that influence the earth – particularly those that are harmful. Be sure to
include the possible consequences of these solar activities. [Relates to Activity 5, 6 & 7 – Particularly the readings: Activity 5 on
pages E50-E55; Activity 7 on pages E73-E77] Key terms to include: ultraviolet radiation; ozone; sunspots; solar flares; solar wind;
planetary nebula; supernova explosion
Solar Activity
Describe the
activity
How often does this What is the impact
activity occur? How of this activity on us
likely is it to occur
Earth?
in the future?
Harmful Solar
Radiation (Types)
Sunspots / Solar
Flares
5 points
Death of our Sun
Death of other stars
5 points
Helpful Solar
Radiation (for extra
credit)
5 points
Up to 3 extra credit points
Source of
Information?
[Text? Incl pages;
Science Notebook?
Incl pages; other?
Include url, etc.]