Lucy about to do close fly-by of Earth in order to slingshot it towards the orbit of Jupiter
Lucy’s route to the asteroids. Click for original image.
On December 12, 2024 the asteroid probe Lucy will do a very close fly-by of Earth, dipping to only 220 miles of the ground and thus giving it the velocity to fly through asteroid belt between Mars and Jupiter and on to the Trojan asteroids that orbit with Jupiter.
During the gravity assist, the Lucy spacecraft, from Earth’s perspective, will approach from the direction of the Sun. This means that observers on Earth will not be able to see Lucy approaching, as it will be lost in the Sun’s glare. Lucy’s trajectory will bring the spacecraft very close to the Earth, even lower in altitude than the International Space Station. To ensure the safety of the spacecraft as it passes through this region full of Earth-orbiting satellites and debris, NASA has procedures to anticipate and avoid potential collisions. If needed, the spacecraft will execute a small trajectory correction maneuver 12 hours before closest approach to alter the time of closest approach by 1 or 2 seconds — enough to avoid a potential collision.
Shortly after sunset, keen observers in the Hawaiian Islands may be able to catch a glimpse of Lucy as the spacecraft approaches Earth before it passes into Earth’s shadow at 6:14 p.m. HST. Lucy will speed over the continental U.S. in darkness, travelling over 33,000 miles per hour (14.8 kilometers per second), and emerge from Earth’s shadow 20 minutes later at 11:34 p.m. EST. At that time, Lucy may be visible to observers with a telescope in the western regions of Africa and the eastern regions of South America as sunlight reflects off the spacecraft’s large solar panels (observers in the eastern United States will be looking at the much dimmer “back” side of the solar panels, making Lucy harder to see
No imagery is planned for this flyby in order to protect the spacecraft’s science instruments.
After the fly-by, Lucy’s next target will be the main belt asteroid Donaldjohanson in April 2025. Its arrival in Jupiter orbit will follow in 2027.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit.
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
Lucy’s route to the asteroids. Click for original image.
On December 12, 2024 the asteroid probe Lucy will do a very close fly-by of Earth, dipping to only 220 miles of the ground and thus giving it the velocity to fly through asteroid belt between Mars and Jupiter and on to the Trojan asteroids that orbit with Jupiter.
During the gravity assist, the Lucy spacecraft, from Earth’s perspective, will approach from the direction of the Sun. This means that observers on Earth will not be able to see Lucy approaching, as it will be lost in the Sun’s glare. Lucy’s trajectory will bring the spacecraft very close to the Earth, even lower in altitude than the International Space Station. To ensure the safety of the spacecraft as it passes through this region full of Earth-orbiting satellites and debris, NASA has procedures to anticipate and avoid potential collisions. If needed, the spacecraft will execute a small trajectory correction maneuver 12 hours before closest approach to alter the time of closest approach by 1 or 2 seconds — enough to avoid a potential collision.
Shortly after sunset, keen observers in the Hawaiian Islands may be able to catch a glimpse of Lucy as the spacecraft approaches Earth before it passes into Earth’s shadow at 6:14 p.m. HST. Lucy will speed over the continental U.S. in darkness, travelling over 33,000 miles per hour (14.8 kilometers per second), and emerge from Earth’s shadow 20 minutes later at 11:34 p.m. EST. At that time, Lucy may be visible to observers with a telescope in the western regions of Africa and the eastern regions of South America as sunlight reflects off the spacecraft’s large solar panels (observers in the eastern United States will be looking at the much dimmer “back” side of the solar panels, making Lucy harder to see
No imagery is planned for this flyby in order to protect the spacecraft’s science instruments.
After the fly-by, Lucy’s next target will be the main belt asteroid Donaldjohanson in April 2025. Its arrival in Jupiter orbit will follow in 2027.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon. from any other book seller, or direct from my ebook publisher, ebookit. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
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