NASA’s New Horizons spacecraft achieved a historic feat in July 2015 when it became the first and only mission to fly by the distant dwarf planet Pluto, capturing stunning images and data of this icy world and its moons. Since this groundbreaking encounter, New Horizons has continued its mission, conducting valuable research as it travels further into space.
On January 1, 2019, New Horizons conducted another pioneering flyby of a Kuiper Belt Object (KBO) named Arrokoth, located beyond Neptune’s orbit. This region, known as the Kuiper Belt, is a vast area filled with leftover icy bodies from the formation of our solar system.
Invaluable Observations
Last year, a report by the U.S. National Academies emphasized the significance of the observations made by New Horizons and Voyager, two of the only spacecraft exploring the outer heliosphere. The report highlighted the importance of understanding this region, which marks the boundary where the sun’s influence wanes.
New Horizons Principal Investigator Alan Stern of the Southwest Research Institute in Boulder, Colorado, described this external validation as crucial. “It’s a completely independent confirmation that the science performed by New Horizons is unique and vital to the field,” Stern stated.
(Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute//Roman Tkachenko)
Guessing Game
New Horizons is currently in hibernation mode, conserving energy as it moves deeper into space. However, the spacecraft continues to gather data related to heliophysics,儲 working effectively with its onboard memory to store information for later transmission.
Stern explained that the spacecraft enters hibernation to save fuel, with the team planning an awakening in April to transmit stored data. He noted that the actual crossing of the termination shock, where the solar wind changes speed, remains uncertain, with a potential timeline spanning from 2027 to an unspecified future date.
Fuel Gauge Reads Low
One of the spacecraft’s primary limitations is its low propellant levels. This restricts the team’s ability to direct New Horizons toward further KBOs, a crucial factor in planning the mission’s next steps.
Stern jokingly adopted the title “Fuel Hoarder in Chief” due to this constraint. However, he remains optimistic that New Horizons will continue to operate effectively, with its nuclear power generating system possibly lasting until 2050.
The prospect of a new KBO flyby depends on discoveries made by Earth-based observatories, such as the Vera C. Rubin Observatory, set to come online soon. If this observatory identifies potential target KBOs within reach, it may increase the chances of another historic flyby.
Unanswered Questions
A team of around a dozen scientists and engineers is analyzing data collected by New Horizons in the outer heliosphere. They are preparing for the spacecraft’s approaching encounter with the termination shock, an exciting opportunity to explore new phenomena.
New Horizons team member Andrew Poppe from the Space Sciences Laboratory at the University of California, Berkeley, noted that Voyager’s measurements left questions unanswered regarding the behavior of pickup ions, particles picked up by the solar wind. With New Horizons’ advanced instruments, scientists hope to resolve these mysteries.
First-Ever Measurements
Poppe emphasized the importance of planning specific observing modes for the termination shock encounter and engaging the broader scientific community to prepare for groundbreaking measurements.
Brandt, the New Horizons project scientist at the Johns Hopkins University Applied Physics Laboratory, highlighted the historical significance of this event, potentially revealing new insights into the boundaries of our solar system.
Historic Encounter
The crossing of the termination shock could last just minutes, but scientists expect multiple encounters over several days as the shock moves around the spacecraft.
Data from this encounter will provide valuable insights for space physicists and pave the way for future missions into interstellar space.
Essence of Exploration
Brandt believes that the Kuiper Belt remains largely unexplored and may extend much further than initially thought. Continuous dust readings defy expectations, suggesting the presence of additional KBOs waiting for discovery.
