Formation of the Extrasolar System(s)

1. Formation of the Extrasolar System(s) M. M. Montgomery UCF Physics

2. Research Focus Extrasolar planets, or exoplanets, are planets NOT from our solar system. Using extrasolar planet Excel data given on the CD ROM, find • the closest & furthest extrasolar planet to its star • the least & most massive extrasolar planet • The shortest and longest period extrasolar planet • Plot Mass of planet (vertical axis) and Distance from its star in A.U. (horizontal axis), print your graph, highlight the habitable zone with a highlighter (see www.astro.sunysb.edu/fwalter/AST101/habzone.html for a similar graph) Using the latest knowledge on the ten most intriguing extrasolar planets from Space.com (see DATA Section below) and your results above, find the numbers of extrasolar planets that fit into each new intriguing class of exoplanets. Draw conclusions whether these new classes are rare or common. How many extrasolar planets fit in your Habitable Zone? What is your definition of life? Based on the data in the table (like mass) and your definition, do you think we may be able to find life on these planets? If so, what kind of life and is this life intelligent? Do you have enough data to draw solid conclusions? Repeat the project using the latest data that can be found at exoplanet.eu. Draw new conclusions. Bonus: Review our current Solar Nebular Theory and establish whether our current theory needs to be updated. If so, formulate new hypotheses based on your data and observations of NASA cartoons of these intriguing extrasolar planets.

3. Context By studying extrasolar planetary data and establishing the habitable zone and the numbers of planets within the habitable zone, we engage students in a multidisciplinary fashion. Physics students can study Kepler’s/Newton’s laws, biology students can determine which planets may harbor life, and chemistry students can study specific planets for atmospheres (hot Jupiters) and whether metabolic processes may be at work. If you think about it, we are actually repeating the words of Galileo, Kepler, Newton, Aristarchus, Copernicus to determine what exosolar planetary systems look like!

4. Method • Using data called Planets Orbiting Other Stars that has been given to us on the CD Rom under And_Beyond_Data/ExtraSolarPlanets, simple analysis of data and simple plots can be generated and much information gained. Note the warnings on the Educator Implications Page. • Latest user-friendly data can be found at exoplanet.eu and the project should be repeated so students can see that conclusions will change with additional data. The advanced student could perform statistical analysis of the data, starting with simple box plots to see if any of the data is unusual and deserves a future look. Other statistical analysis could be used to compare, contrast, classify, evaluate, conclude, and revise current knowledge and understanding.

5. Data Summary (Part 1) For Example, I compared Planetary Mass (in Jupiter masses) as a function of Distance from its star (in A.U.) and found • Min Distance = 0.0177 A.U. (HD 41004 Bb) • Max Distance = 10.4 A.U. (HD 154345 b) • Min. Mass = 0.0185 Jupiter mass (GJ 876 d) • Max Mass = 22.7 Jupiter mass (HD 147510 b) • Min Period = 1.3283 d (HD 41004 B b) • Max Period = 13100 d (HD 154345 b)

6. Data Summary (Part 2) Using our CD ROM data set, I found through a quick analysis …. • No USPPs • No planemos or free floaters • Hot Jupiters are plenty • Future - Are they Fire/Ice Planets (I.e., tidally locked)? • Far-away planets • Future - Do they have liquid water?

7. Conclusion • Simple data analysis could suggest selective effects in data collection. • Simple data analysis could suggest that extra solar system nebula theory may need revision (or creation!) but possibly the solar system theory does not need revision • No data is given on inclination of axis w/r/t ecliptic plane, so conclusions can’t be drawn • No data is given on dusty disks in these systems, so conclusions can’t be drawn

8. Implications • Future work involves redoing the work with the latest data at exoplanet.eu. • Future work could involve comparing planetary data with their dusty disks and thus ages as well on inclination angles to determine formation (NASA grant?)

9. Educator Implications • Pre-service teachers are already engaged in teaching teachers of multiple disciplines. Students are used to learning about multiple fields in a single year (e.g., chemistry, physics, biology). Future jobs/careers (e.g., climatology, life in the Universe, astromedical) also seem to be multi-disciplinary. We need to keep education projects multidisciplinary to match trends in future employment. • Warning: Exoplanet data is highly selective based on our current technology used to acquire it (i.e., we find large planets as our technology is geared to find them!) and you should draw this conclusion when repeating the project twice with the newest data. Also, when attempting the project, you will need to retype the existing data as some of the numbers with decimals have parentheses around them, indicating errors, and you’ll need to remove these in your Excel spreadsheet.

10. Data 2008/2009 10 Most Intriguing Planets (from Space.com)

11. DATA 2008/9 Ten Most Intriguing Extrasolar Planets

12. Hot Jupiters The first planet discovered in orbit around a normal star other than our Sun is 51 Pegasi b. This planet is a Hot Jupiter as it orbits eccentrically and, at its closest distance, it is closer to its star than Mercury is to the Sun. Are there any Hot Jupiters in your data?

13. Alien Life? Epsilon Eridani b orbits an orange Sun-like star but this exoplanet orbits too far away from its star to support liquid water and thus life as we know it on Earth. This system is 10.5 ly from Earth. Being so close, we may soon be able to photograph this system to find the other stars in this system that may harbor life. Are any of your planets in the habitable zone?

14. Free Floaters/Planemos Some exoplanets, called planemos, are celestial objects that are similar to, but smaller than, brown dwarfs (I.e., stars with not enough mass to continue nuclear fusion in their cores). However, these exoplanets have no Suns! That is, they float untethered in space. Are any of your planets free floaters?

15. Ultra-Short-Period-Planets SWEEPS-10 orbits so close to its parent star (~740,000 miles away) that it orbits its star once every 10 Earth-hours! (Remember Earth takes 1 year to orbit the Sun, not 10 hours!) This type of exoplanet is called ultra-short-period planets (USPPs). Are any of your planets fast orbiters?

16. Fire and Ice Upsilon Andromeda b is tidally locked to its Sun like the Moon is to Earth (notice we always see the same face of the Moon each night the Moon is up?), creating one of the largest temperature differences ever seen on an exoplanet. One side of the planet is always as hot as lava whereas the other side is always a cold as freezing. Are any of your planets Fire and Ice Planets?

17. Youngest Exoplanet Less than 1 million years old, this exoplanet orbits Coku Tau 4, a star 420 ly from Earth. An enormous hole in the dusty disk that girdles the star suggests the presence of a planet. Does your data have an exoplanet as young as this one?

18. Oldest Planet A primeval world, aged 12.7 billion years, began 2 billion years after the Big Bang and 8 million years before Earth. The planet orbits both a pulsar PSR B1620-26 and its companion, a white dwarf. These statistics suggest that life in the Universe may have begun earlier than previously thought. Does your data indicate an old planet?

19. Shrinking planet? HD209458b orbits so close to its star that its year is only 3.5 Earth-days long! This planet’s atmosphere is being blown away by stellar winds. The planet loses ~10,000 tons of material every second, shrinking the planet. It may end as a dead core. Are any of your planets shrinking?

20. Hot Juptier’s Atmosphere This hot jupiter’s atmosphere contains thick clouds of silicates similar to grains of sand. Theory of Hot Jupiters expects water and methane to be present. However, no water vapor or methane is detected. The water vapor may still be hidden beneath the clouds though. Does your data indicated elements and thus the planets chemical make-up?

21. Smallest Exoplanet Gliese 581c is the smallest detected to date and the first to lie within the habitable zone of its parent star. Its surface may sustain liquid water and possibly life as we know it on Earth. This exoplanet is 50% bigger and 5x more massive than Earth. Is this planet listed in your data? Which planet in your data is the smallest?