Latest / Star Trails: From Backyard Astronomy to Cosmic Wonder / Summer’s Cosmic Wonders and Martian Milestones
Transcript
- Hello, star gazers and celestial enthusiasts! Welcome to another episode of Star Trails. I'm your host, Drew, and this week, we're diving into the cosmic wonders that await us from June 23rd to June 29th, 2024. This week, there's something for every backyard astronomer to enjoy. So, let's get started! Let's begin with our closest celestial neighbor, the Moon. This week, we start with the Waning Gibbous phase after the Full Moon on June 22nd. As the week progresses, the Moon continues to wane, reaching the Last Quarter on June 28th. By June 29th, the Moon enters its Waning Crescent phase, making for excellent stargazing as the skies become darker in the evenings. Next, let's talk about the visible planets. This week is a fantastic time to spot several of our planetary neighbors. Venus, is an evening star, shining brightly near the horizon in the western sky after sunset. Venus is very close to the sun, so you may catch it for only about an hour after sunset before it too dips below the horizon. You may have a better shot at Mercury as it lingers a bit longer after sunset just above the west-northwest horizon. Mars can be seen in the early morning sky, best visible in the pre-dawn hours, rising around 3 AM and remaining visible until sunrise. Jupiter, the giant of our solar system, rises in the early morning around 4:30 AM and can be seen just before sunrise. Look for it in Taurus, over the eastern horizon. Saturn may be your best bet this week. It rises after midnight and remains visible until dawn. This week Saturn is dancing with the moon, and the two will be at their closest in the predawn hours of June 27th. Look for the pair on the edge of Aquarius over the southern horizon. Keep in mind, Saturn’s rings are in a unique edge-on orientation to the Earth, so the rings look thinner than usual. This phenomenon is known as a “ring-plane” crossing, and happens about every 15 years. Through a small telescope, it appears the rings are shrinking. There are plenty of spectacular constellations visible this time of year. I’ll highlight a few we haven’t discussed in detail before. Sagittarius is located near the core of the Milky Way and is a treasure trove of deep sky objects, including star clusters and nebulae. One of the most prominent features of Sagittarius is the "Teapot" asterism, which is easily recognizable. The constellation is home to the Lagoon Nebula (M8), a giant interstellar cloud visible with binoculars or a small telescope. Sagittarius also houses the Trifid Nebula (M20) and the Sagittarius Star Cloud, regions rich in star formation. In mythology, Sagittarius is often associated with the centaur Chiron, who was a wise and skilled healer and teacher. Chiron was placed in the sky by Zeus to honor his knowledge and benevolence. Cygnus, the Swan, is rising higher in the eastern sky and is home to the beautiful double star Albireo, which shows a striking color contrast through a telescope. The constellation's brightest star, Deneb, forms part of the Summer Triangle along with Vega in Lyra and Altair in Aquila. Deneb is one of the most luminous stars known, shining with the power of about 196,000 suns. According to Greek mythology, Cygnus represents the swan into which Zeus transformed himself to seduce Leda. Another story tells of the friendship between Phaethon and Cygnus. After Phaethon’s tragic fall from the Sun chariot, Cygnus mourned his friend and was turned into a swan by the gods, who placed him in the sky. A lesser-known but unique constellation is Ophiuchus, the Serpent Bearer. Ophiuchus is located near the celestial equator and is often depicted as a man holding a serpent. This constellation is unique because it is one of the 13 constellations that the Sun passes through during the year, although it is not traditionally included in the zodiac. In mythology, Ophiuchus is associated with Asclepius, the Greek god of medicine, who learned the secret of immortality from a serpent. Zeus placed Asclepius in the sky to honor his contributions to humanity but also to prevent him from making humans immortal. Within Ophiuchus lies Barnard's Star, the second closest star system to Earth, after the Alpha Centauri system. Barnard's Star is particularly notable for its high proper motion, which is the apparent movement of the star across the sky relative to more distant background stars. This high proper motion, the highest known for any star, indicates its rapid movement through space and its relative proximity to Earth – a mere 6 light years – making Barnard's Star a valuable object of study for astronomers. After a short break, I’ll return to discuss a significant moment in the history of space exploration that occurred back in 1997 – The Mars Pathfinder mission. Stay with us! On December 4, 1996, a groundbreaking mission embarked on a voyage that would revolutionize our understanding of the Red Planet. The Mars Pathfinder mission, launched by NASA, was not just a leap forward in technology but a giant step in our quest to uncover the secrets of Mars. The story of Mars Pathfinder begins with the ambitious goal to develop a cost-effective and reliable method to land scientific instruments on the Martian surface. This mission was part of NASA's Discovery Program, which aimed to explore the solar system with highly focused and scientifically valuable missions. The Pathfinder mission was unique in many ways. It featured an innovative airbag landing system designed to cushion the spacecraft's impact on the Martian surface. This technique was a stark departure from previous methods and marked a significant technological advancement. The spacecraft itself was composed of two main components: the lander, later named the Carl Sagan Memorial Station, and a small, six-wheeled rover called Sojourner. Named after the civil rights crusader Sojourner Truth, the Sojourner rover was the real star of the show. Weighing in at just 23 pounds and measuring only about two feet in length, this little rover was packed with scientific instruments. It was designed to analyze the Martian soil and rocks, send back detailed images, and perform a variety of experiments to help scientists understand the planet's geology and climate. After a seven-month journey through space, Mars Pathfinder arrived at its destination, entering the Martian atmosphere on July 4, 1997. The landing process was nothing short of nail-biting. As the spacecraft descended, it deployed a series of parachutes to slow its speed. Moments before impact, a cluster of airbags inflated around the lander, cushioning its fall as it bounced and rolled across the Martian terrain. Once the dust settled, the airbags deflated, and the petals of the lander unfolded, revealing the Sojourner rover nestled inside. For the first time, a robotic explorer was ready to roam the surface of Mars, and the world watched with bated breath. The first images from Mars Pathfinder were transmitted back to Earth just hours after landing. These stunning pictures showed a landscape strewn with rocks of various shapes and sizes, a testament to the planet's tumultuous history. Over the course of its mission, Sojourner conducted detailed analyses of the Martian rocks and soil, providing invaluable data about the planet's composition and past. One of the key findings from the mission was the discovery of rounded pebbles and conglomerates in the Ares Vallis landing site. These formations suggested that liquid water once flowed on Mars, carving channels and depositing sediments. This evidence of past water activity fueled speculation about the possibility of ancient Martian life and set the stage for future missions to search for signs of habitability. The success of Mars Pathfinder was not just scientific; it was also a triumph of engineering and ingenuity. The mission demonstrated the effectiveness of the airbag landing system, a method that would be used in subsequent missions like the Mars Exploration Rovers, Spirit and Opportunity. It also showcased the potential of small, robotic rovers to explore and conduct science on other planets, paving the way for more sophisticated rovers like Curiosity and Perseverance. Mars Pathfinder and the Sojourner rover operated far beyond their expected lifespans. The mission was initially planned to last 30 days, but the rover continued to send data for nearly three months, with the final transmission received on September 27, 1997. The mission's legacy lives on in the ongoing exploration of Mars and our ever-expanding understanding of the universe. So, the next time you gaze up at the night sky and spot that reddish dot among the stars, remember the incredible journey of Mars Pathfinder and the little rover that could. That’s all for this week’s episode of Star Trails. Before you go, I invite you to check out our weekly e-mail newsletter on Substack, where you can receive night sky reports and astronomy news that we don’t always mention on the podcast. It’s completely free, and a great supplement to the podcast. We’re also on Mastodon @star_trails and we’d love to hear from you. I’ll include links to both services in the show notes. Also, remember our website, startrails.show, where you can find all our episodes, including transcripts. Until next time, keep looking up! Clear skies!