NASA's Asteroid-Seeking Spacecraft Prepared for Earth Flyby Tonight, Live Stream Available
The asteroid explorer spacecraft named Lucy is set to perform its second close approach to Earth today, utilizing our planet as a slingshot to boost its speed towards a cluster of asteroids known as the Trojans.
Embarking on a 12-year adventure into the outer reaches of our solar system, Lucy's primary objective is to examine this group of asteroids to shed light on the genesis of the outer planets and the formation of our solar system. The spacecraft requires a nudge to accomplish its mission, and its scheduled encounter with Earth is scheduled for tonight, around 11:15 p.m. Eastern Time, according to NASA's communication.
Contrary to popular belief, once a spacecraft takes off, it's often thought to be out of reach forever. However, spacecrafts typically have limited fuel supplies and often rely on the gravitational pull of solar system objects to expedite their journey to distant regions. Tonight, Lucy will do just that, using Earth's gravitational pull for a much-needed boost on its way to the Trojan asteroids.
As Lucy gracefully glides over Earth tonight, it will be traveling at an extraordinary speed of more than 33,000 miles per hour (53,100 kilometers per hour). During its passage, Lucy will spend approximately 20 minutes within Earth's shadow before reemerging. At its closest approach, discerning observers with telescopes in western Africa or eastern South America might catch a glimpse of Lucy.
Unfortunately, viewers in the Eastern United States will have a more challenging time spotting Lucy as we will be located on the shadow side of its solar panels. On the contrary, observers on the other side of the spacecraft will benefit from the light reflecting off the surfaces, making it easier to spot. The Virtual Telescope Project 2.0 is also offering a live broadcast (accessible above) of Lucy's journey as it swings by our world.
Earlier this week, the European Space Agency's BepiColombo spacecraft conducted its fifth flyby of Mercury, paving the way for its arrival in Mercury's orbit in November 2026. In November, NASA's Parker Solar Probe made its final flyby of Venus, utilizing Venus's gravity to catapult itself towards the surface of our star. Parker's closest approach to the Sun is set for Christmas Eve.
A diagram depicting Lucy's second Earth gravity assist. Image source: NASA
Interestingly, this encounter with Earth is Lucy's second; its first occurred in October 2022, enabling the spacecraft to swing by the small asteroid Dinkinesh. The upcoming gravity assist will propel Lucy into a six-year orbit, sending it through the asteroid belt and towards the Trojan asteroids, with an anticipated encounter slated for 2027. The gravitational force will amplify Lucy's speed relative to the Sun by an impressive 16,000 miles per hour (25,750 kilometers per hour).
Next on Lucy's itinerary is the main belt asteroid Donaldjohanson, which it will pass on April 20, 2025. From there, Lucy will continue its journey – infinity, or perhaps the asteroid belt, awaits.
In the future, advancements in science and technology could allow for more frequent and elaborate space missions like Lucy's, transforming our understanding of the solar system's formation. With Earth's gravity aid, Lucy's speed towards the Trojan asteroids accelerates significantly, showcasing the crucial role of spacecraft manipulation in deep space navigation.
