Sara Seager - New planets around the nearest stars

The Immense Scale of the Universe

• 💡 Our Milky Way galaxy alone contains hundreds of billions of stars, and the universe has hundreds of billions of galaxies.
• 🚀 Every star is a sun with planets, and astronomers have already discovered thousands of planets orbiting other suns.
• 🌌 The sheer number of stars and planets makes the universe's vastness almost incomprehensible.

Distances to Other Stars

• 🔭 Stars are incredibly far away, even the closest ones to us.
• 🌠 Proxima Centauri, our nearest star, is over four light-years away, which is more than 20 trillion miles.
• 🛰️ Even the fastest human-made spacecraft, like Voyager, would require nearly 100,000 years to reach the nearest star.

Evolution of Astronomy

• 📜 Historically, people used stars for navigation and to mark seasons, with early astronomers often serving as astrologers.
• ❌ Ancient astronomy lacked the tools for magnification or precise measurements of distant celestial bodies.
• 📱 Today, technological developments, similar to those in everyday innovations like smartphones, are significantly advancing astronomical study.

Discovering Exoplanets

• 🔍 The primary technique currently used for finding exoplanets is called the transit method.
• 💡 This method relies on a planet passing directly in front of its star as observed from Earth.
• 💻 Astronomers employ sophisticated computer algorithms to simultaneously monitor tens of thousands of stars for signs of transiting planets.

The Transit Method Explained

• 📉 The transit method detects a tiny, repeated drop in a star's brightness when an orbiting planet crosses its path.
• 📏 The amount of starlight blocked is directly related to the planet-to-star area ratio.
• ✅ Repeated occurrences of these brightness drops confirm the presence of an orbiting exoplanet.