Astronomy �Merit Badge

Presenter: Tara Jordan

Troop 742

Requirements

Requirements

1. Do the following:
1. Explain to your counselor the most likely hazards you may encounter while participating in astronomy activities, and what you should do to anticipate, help prevent, mitigate, and respond to these hazards.
2. Explain first aid for injuries or illnesses such as heat and cold reactions, dehydration, bites and stings, and damage to your eyes that could occur during observation.
3. Describe the proper clothing and other precautions for safely making observations at night and in cold weather. Then explain how to safely observe the Sun, objects near the Sun, and the Moon.

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Requirements

2. Explain what light pollution is and how it and air pollution affect astronomy.
3. With the aid of diagrams (or real telescopes if available), do each of the following:
1. Explain why binoculars and telescopes are important astronomical tools. Demonstrate or explain how these tools are used.
2. Describe the similarities and differences of several types of astronomical telescopes, including at least one that observes light beyond the visible part of the spectrum (i.e., radio, X-ray, ultraviolet, or infrared).
3. Explain the purposes of at least three instruments used with astronomical telescopes.
4. Describe the proper care and storage of telescopes and binoculars both at home and in the field.

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Requirements

4. Do the following:
1. Identify in the sky at least 10 constellations, at least four of which are in the zodiac.
2. Identify at least eight conspicuous stars, five of which are of magnitude 1 or brighter.
3. Make two sketches of the Big Dipper. In one sketch, show the Big Dipper's orientation in the early evening sky. In another sketch, show its position several hours later. In both sketches, show the North Star and the horizon. Record the date and time each sketch was made.
4. Explain what we see when we look at the Milky Way.

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Requirements

5. Do the following:
1. List the names of the five most visible planets. Explain which ones can appear in phases similar to lunar phases and which ones cannot, and explain why.
2. Using the Internet (with your parent's permission), books, and other resources, find out when each of the five most visible planets that you identified in requirement 5a will be observable in the evening sky during the next 12 months, then compile this information in the form of a chart or table.
3. Describe the motion of the planets across the sky.
4. Observe a planet and describe what you saw.

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Requirements

6. Do the following:
1. Sketch the face of the moon and indicate at least five seas and five craters. Label these landmarks.
2. Sketch the phase and the daily position of the Moon at the same hour and place, for four nights within a one week period. Include landmarks on the horizon such as hills, trees, and buildings. Explain the changes you observe.
3. List the factors that keep the Moon in orbit around Earth.
4. With the aid of diagrams, explain the relative positions of the Sun, Earth, and the Moon at the times of lunar and solar eclipses, and at the times of new, first-quarter, full, and last-quarter phases of the Moon.

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Requirements

7. Do the following:
1. Describe the composition of the Sun, its relationship to other stars, and some effects of its radiation on Earth's weather and communications.
2. Define sunspots and describe some of the effects they may have on solar radiation.
3. Identify at least one red star, one blue star, and one yellow star (other than the Sun). Explain the meaning of these colors.

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Requirements

8. With your counselor's approval and guidance, do ONE of the following:
1. Visit a planetarium or astronomical observatory. Submit a written report, a scrapbook, or a video presentation afterward to your counselor that includes the following information:
• Activities occurring there
• Exhibits and displays you saw
• Telescopes and instruments being used
• Celestial objects you observed.
2. Plan and participate in a three-hour observation session that includes using binoculars or a telescope. List the celestial objects you want to observe, and find each on a star chart or in a guidebook. Prepare a log or notebook. Discuss with your counselor what you hope to observe prior to your observation session. Review your log or notebook with your counselor afterward.
3. Plan and host a star party for your Scout troop or other group such as your class at school. Use binoculars or a telescope to show and explain celestial objects to the group.
4. Help an astronomy club in your community hold a star party that is open to the public.
5. Personally take a series of photographs or digital images of the movement of the Moon, a planet, an asteroid, a meteor, or a comet. In your visual display, label each image and include the date and time it was taken. Show all positions on a star chart or map. Show your display at school or at a troop meeting. Explain the changes you observed.

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Requirements

9. Find out about three career opportunities in astronomy. Pick one and find out the education, training, and experience required for this profession. Discuss this with your counselor, and explain why this profession might interest you.

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Preparation

Parts 1-3 of the Merit Badge involve preparing yourself with the proper skills and tools for astronomical observations.

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Hazards

• Weather: Dress appropriately for being outdoors for extended periods of time. Be prepared for changes in temperature when going from daytime to nighttime.
• Insects and animal bites: Use bug spray and cover exposed skin. Wear closed toed shoes.
• Darkness: Prepare your site during the daytime and note/mark any holes, crevices, or other tripping hazards. Use red-filtered flashlights.
• Eye damage: Never look directly at the Sun, even if you are wearing sunglasses. Never look at the Sun through binoculars or telescopes without proper lens.
• Dehydration: Stay well hydrated when outdoors. Do not wait to drink until you feel thirsty.

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First Aid

• When you are doing daytime viewing (such as a solar eclipse) or setting up equipment for later use, be aware of and protect yourself from sun exposure.
• Sunburn: Wear appropriate clothing, hats, and sunscreen. Reapply sunscreen often.
• Heat exhaustion and Heatstroke: Heat exhaustion is where body overheats and a person appears pale, clammy, sweaty and reports nausea, dizziness or shows symptoms of dizziness or pronounced weakness. Treat by laying the person in a cool area or near a fan with legs elevated. Loosen clothing and apply damp cloths to the skin. If the person becomes confused, disoriented, starts convulsing the condition has worsened to heatstroke. Cool them immediately. Put them in a cold bath or stream if possible. Seek medical attention; call 911.

First Aid

• Temperatures can drop during the night time, and winter months are often better for astronomy viewing. Be aware of and protect yourself from cold exposure. Bring layers for viewing including a hat, gloves, scarf, extra socks, and a coat.
• Hypothermia: Initially a person will shiver. As the person gets colder, the shivering will stop and a person may get irritable, sleepy, incoherent, confused, or disoriented. Move the person to a shelter, remove damp clothing, wrap in a blanket or sleeping bag, and offer hot drinks. Severe hypothermia will require medical attention.

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Proper Observations

• Sun/Solar Eclipse: The best way to look at the Sun is by projection. You can make a pinhole viewer out of a cereal box.

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Proper Observations

• Objects near the sun: Look for Mercury only when the sun is below the horizon. Mercury is visible only in bright twilight and is either very low in the western sky after sunset or very low in the east before sunrise.
• Moon: When doing any astrological viewing, it is important to know the phase of the Moon. If viewing the Moon itself, it is ideal for it to be close to a Full Moon. For other observations, a New Moon might be ideal so less light interferes with your viewing.

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Light Pollution

• Light pollution is artificial light introduced into the natural night, especially where it is not needed or wanted. This unwanted light appears in the sky, causing sky glow, obscuring the stars and creating perpetual twilight.

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Other Viewing Limitations

• Air Pollution: In the US, pollutants from power plants and vehicle exhausts are the primary cause of haze in the Eastern US.

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• Natural Conditions: Air turbulence, humidity, and clouds can also interfere with your ability to view the night sky unencumbered.

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Binoculars

• Binoculars allow you to use both eyes to view.

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• Binoculars show the image the right way up (as opposed to telescopes that show the image upside down).

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• Binoculars are easier to transport and can be handheld.

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• Binoculars are often cheaper than telescopes.

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Binoculars

Refracting Telescopes

• Refracting telescopes: Use a system of lenses to collect and focus the incoming light.
• These are the earliest type of telescopes, first patented by Galileo Galilei in 1609.
• Refracting telescopes are generally better for bright objects like the Moon.

Reflecting Telescopes

• Reflecting telescopes: Use a system of mirrors to concentrate incoming light.
• The first reflecting telescope was invented by Isaac Newton in 1668.
• Reflecting telescopes are better suited for deep-sky objects like star clusters and nebulas.

Proper Care of Binoculars and Telescopes

• Handle carefully and with respect. Try not to bump, shake or drop the instruments.
• Keep the equipment clean. Use a microfiber cloth with cleaner specifically made for lenses to clean. Apply cleaner to the cloth, not directly to the lens.
• Keep dust off lenses. Keep them covered with lens caps.
• Protect the equipment from water, especially saltwater.
• Use and wear the strap that comes with binoculars.
• Store instruments in a cool, dry place away from humidity and extreme temperatures.

Space Telescopes

• Radio, ultraviolet, infrared , x-ray and gamma ray telescopes detect light outside of the visible electromagnetic spectrum.
• Ultraviolet telescopes help astronomers study the formation of stars and galaxies. Because most ultraviolet waves are blocked by the Earth’s atmosphere, ultraviolet telescopes must be placed in space.
• Infrared and x-ray telescopes detect light and energy emitted by objects in space. They can see into the coldest and dustiest areas of space.

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Hubble Space Telescope

• The Hubble Space Telescope was launched in 1990. It can see from ultraviolet through the visible light spectrum.

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• It is classified as a Cassegrain reflector. It’s primary mirror is 94.5 inches in diameter.

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• It has made more than 1.4 million observations.

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Chandra Space Telescope

• The Chandra X-Ray Telescope was launched in 1999. It can see from visible light through x-ray.

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• It is classified as a Wolter x-ray telescope.

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• Chandra observations have helped provide evidence of black holes, pulsars, and neutron stars.

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Multiwavelength Astronomy

Multiwavelength Astronomy

Multiwavelength Astronomy

Multiwavelength Astronomy

Other Instruments

• Spectrograph: An instrument that separates light coming from a star into a pattern of colored lines (or spectrum). The more these lines are shifted to the red end of the spectrum, the farther away the star is from us. This is how we find the distance to stars in our part of the galaxy.
• Filar Micrometer: Identifies the distance between two objects that are very close together, such as binary stars (suns that orbit each other). By knowing this distance, and by observing the increase and decrease in brightness, astronomers can deduce the mass of each star.
• Photometer: Measures the brightness (luminosity) of a star; that is, the magnitude. By knowing the magnitude and the distance, astronomers can determine the size of the star, which helps identify their age. Photometers are also used to discover exoplanets (planets orbiting other stars).

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Observations

Parts 4-8 of the Merit Badge involve learning about and observing different astronomical objects such as stars, constellations, planets, and the Moon.

The Sky

• The Earth moves in a counterclockwise spin (from west to east), so it makes the sky appear to rotate in the opposite direction, from east to west.
• The east-west path that the Sun, planets, and the Moon follow is called the ecliptic.
• If you watch the night sky for a few hours, you will see that the stars appear to rotate about a fixed point in the sky (which happens to be near the pole star, Polaris).
• Umbrella model by H.A. Rey: https://www.youtube.com/watch?v=RclpJt43mTU

Conspicuous Stars

• A conspicuous star is a bright star that is easily seen with the naked eye. A star’s magnitude is a measure of how bright it is.
• Absolute magnitude is the star’s true brightness if all stars were viewed from the same distance.
• Apparent magnitude is the brightness of a star from Earth.
• The lower the apparent magnitude number, the brighter the star. Stars brighter than a magnitude of 1 have a zero or negative number.

Conspicuous Stars

Constellations

• Constellations are groups of visible stars that form a perceived outline or patter, typically representing an animal, mythological being, or object.
• In 1922, the International Astronomical Union (IAU) codified the modern sky map and adopted official constellation boundaries.
• There are 88 official constellations in the sky.
• Asterisms are other star patterns that are used by observers. An example of an asterism is the Big Dipper, which is a small section of Ursa Major.

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Circumpolar Constellations

• Due to the Earth’s rotation and axial tilt, there are constellations that never appear to rise or set. These are called circumpolar constellations.
• In the Northern Hemisphere (where we live), these stars cluster around the star Polaris. Polaris is sometimes called the North Star or the Pole Star.
• Northern circumpolar constellations include Ursa Major, Ursa Minor, Draco, Cepheus, Cassiopeia, and Camelopardalis. These constellations are visible at most times of the year.

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Circumpolar Constellations

Zodiacal Constellations

• There is a singular path that the Sun, Moon, and planets appear follow through the sky called the ecliptic.
• The 12 zodiacal constellations map the ecliptic. You can see them in the evening sky during different seasons.
• Astrology is the belief that the zodiacal constellation that was rising at the time when you were born somehow influences your personality.

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Zodiacal Constellations

Seasonal Constellations

• Some constellations (including all zodiacal constellations) are only visible at certain times of the year.
• Spring: Leo, Virgo, Libra, Cancer
• Summer: Lyra, Cygnus, Aquila, Scorpius, Sagittarius
• Fall: Pegasus, Andromeda, Perseus, Aries, Pisces, Capricornus, Aquarius
• Winter: Orion, Canis Major, Gemini, Auriga, Taurus

The Milky Way

• Our solar system is part of a spiral galaxy called the Milky Way. Our galaxy's vast rotating disk of stars spans at least 170,000 light-years, and possibly up to 200,000 light-years.
• When we look up and see the Milky Way in the sky, we are looking edge-on at our galaxy.
• Pretend you are an atom inside a Frisbee. You are located about 2/3rds of the way from the center, closer to the edge. Now, look all around you. As you look at the Frisbee, you see the stars that make up our galaxy. When you look up or down, away from the Frisbee, you are looking at Globular Clusters, a few stray stars, and other galaxies (other Frisbees).

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The Milky Way

The Milky Way

Planets

• Mercury, Venus, Mars, Jupiter, and Saturn were indentified by ancient Babylonian astronomers . Records can be found dating back to 1000 BCE.   The word planet comes from the Greek word planetes, meaning “wanderer.” The Greeks noted that the planets moved independently of the fixed stars.
• Because the planets wander around the sky and do not stay fixed in a particular location, you will need to research which planets are visible prior to your astronomical observations. Most guides will tell you what time and what constellation to look in.
• This is for 2020: https://www.space.com/39240-when-to-see-planets-in-the-sky.html

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Planets

Planets

Planets

• The ‘inferior’ planets – so called because they are inside of Earth’s orbit – appear to have phases like our Moon. It is easy to see these phases on Venus with binoculars. You will need a telescope to see the phases of Mercury, but wait until the Sun has set or look before it has risen. As these two planets travel around the Sun, we can see the sunlight hitting their surface as well as part of the planet that the Sun cannot reach.
• The ‘superior’ planets, Mars, Jupiter, and Saturn, are outside of Earth’s orbit. This means that we always get the same view of the planet as the Sun, and therefore cannot see the part of the planet where the sun doesn’t shine. So we are unable to see the phases.

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Phases of Venus

Moon

• The Moon is the Earth’s only natural satellite. It is the brightest object in the night sky.
• Gravity and inertia are forces that act to keep the Moon in rotation around the Earth.
• The Earth pulls the Moon towards the Earth with gravity. Without gravity, the Moon would fly away in the direction it was moving when gravity disappeared. The Moon also exerts gravity on the Earth. This is what causes the ocean’s tides.
• Inertia is an object’s resistance to change when in motion. Without inertia (Newton’s First Law of Motion), the Earth and Moon would collide.  

Moon

• The Moon is in synchronous rotation with Earth, and thus always shows the same side to Earth, the near side.
• The face of the Moon is covered with mountains, plains, valleys, and is marked with craters.
• When you look at the Moon at night, you can see light areas and dark areas. The dark areas were named marias (seas) because the astronomers in the 1600s thought they were bodies of water. The light areas were named terrae (lands).
• The Moon also has millions of pits, called craters, covering its surface.

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Moon

Moon Phases

• The moon takes about 29 days to make a full circuit (revolution) around the Earth.
• The Sun always illuminates the Moon, but as the Moon orbits the Earth, we cannot always see the illuminated area.
• The Moon goes through phases. It is said to wax from New Moon to Full Moon and then to wane from Full Moon to New Moon.

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Moon

Eclipses

• An eclipse happens when the Moon moves directly into line with the Earth and the Sun. Eclipses only happen during the New Moon or Full Moon, and only when the Moon is in the Earth’s orbital plane.
• There are two types of eclipses: Solar eclipses and lunar eclipses.
• Solar Eclipse: The Moon passes directly between the Earth and the Sun so that the Moon’s shadow strikes the Earth. During a total solar eclipse, the light from the Sun is completely blotted from view.
• Lunar Eclipse: The Moon passes directly behind the Earth, passing into the Earth’s shadow.

Solar Eclipse

Solar Eclipse

Lunar Eclipse

Lunar Eclipse

Sun

• The Sun is mainly hydrogen and helium, which are the two lightest chemical elements.
• The Sun’s core is only about 2% of the volume but 60% of the mass of the Sun. This is where nuclear fusion occurs, which turns hydrogen to helium and other lighter elements like carbon into heavier elements like iron. Because the Sun is so massive, the pressure in the core squeezes these atoms together making heavier elements and releasing massive amounts of energy – like an atomic bomb. This energy radiates from the core outward, heating up the rest of the Sun (convection), and eventually escaping the Sun to warm its Solar System.

Sun

• The surface of the Sun is called the photosphere.
• Sunspots are cooler areas on the photosphere. They are not permanent features.
• When sunspots are plentiful, there seems to be more solar activity and releasing of radiation and matter into space. These bursts of radiation can reach Earth and knock out satellite transmissions like TV, radio, and other communications. They are also hazardous to astronauts who do not have the Earth’s atmosphere to protect them.

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Sun

• The Sun’s energy drives weather and climate on Earth. It heats the atmosphere, creates warm air masses which create wind, and evaporates water.
• The Earth has seasons due to its tilted axis, which keeps the northern hemisphere tilted towards the Sun for half the year and away for the other half of the year. Thus, the northern hemisphere gets more sun during the summer and less sun during the winter.

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Star Quality

• Blue and Blue-White Stars: The hottest stars with temperatures ranging from 18,000 to more than 45,000 degrees F. An example is Rigel in Orion.
• White Stars: White stars have temperatures from 13,500 to 18,000 degrees F. Examples would be Sirius in Canis Major and Polaris in Ursa Minor.
• Yellow Stars: Yellow stars are cooler with temperatures of 9,000 to 13,500 degrees F. The Sun is a yellow star. Others are Lambda in Sagittarius and Zeta in Cygnus.
• Orange Stars: Orange stars are between 6,000 and 9,000 degrees F. Arcturus in Bootes is an orange star.
• Red Stars: The coolest stars are red, and are less than 6,000 degrees F. Betelgeuse in Orion is a red star.

Hertzsprung-Russell Diagram

Astronomy Careers

Part 9 of the Merit Badge involves learning about different career opportunities in astronomy.

Astronomy Careers

• If you would like to consider a career in astronomy, it would be best if you were observant, logical, curious, and determined. Astronomers are typically very good at math and science.
• Possible careers that you could consider include Astronomer, Astrophysicist, Planetarium Administrator, Astronomy Writer/Editor, Science Teacher, Computational Astrophysicist, Aeronautical Engineer, or Meteorologist.
• https://www.indeed.com/career-advice/finding-a-job/astronomy-jobs

Homework and Star-Party Work

• 4a. Identify in the sky 10 constellations, at least 4 of which are in the zodiac.
• 4c . Make two sketches of the Big Dipper. In one sketch, show the Big Dipper's orientation in the early evening sky. In another sketch, show its position several hours later. In both sketches, show the North Star and the horizon. Record the date and time each sketch was made.
• 5b. Using the Internet (with your parent's permission), books, and other resources, find out when each of the five most visible planets that you identified in requirement 5a will be observable in the evening sky during the next 12 months, then compile this information in the form of a chart or table.
• 5d. Observe a planet and describe what you saw.
• 6a. Sketch the face of the moon and indicate at least five seas and five craters. Label these landmarks.
• 6b. Sketch the phase and the daily position of the Moon at the same hour and place, for four nights within a one week period. Include landmarks on the horizon such as hills, trees, and buildings. Explain the changes you observe.
• 7d. Identify at least one red star, one blue star, and one yellow star (other than the Sun). Explain the meaning of these colors.
• 8b. Plan and participate in a three-hour observation session that includes using binoculars or a telescope. List the celestial objects you want to observe, and find each on a star chart or in a guidebook. Prepare a log or notebook. Discuss with your counselor what you hope to observe prior to your observation session. Review your log or notebook with your counselor afterward.
• 9. Find out about three career opportunities in astronomy. Pick one and find out the education, training, and experience required for this profession. Discuss this with your counselor, and explain why this profession might interest you.��