Launched in 2006, New Horizons aimed to understand the development of Pluto, the Kuiper Belt, and the solar system. Its historic flybys of Pluto in 2015 and the Kuiper Belt Object Arrokoth in 2019 generated worldwide New Horizons expand research with unique observationss and numerous scientific results. The spacecraft has since sent back remarkable images and data from the edge of the solar system.

"A good tool can be used for many things," said Joel Parker, New Horizons deputy project scientist from the Southwest Research Institute (SwRI) in Boulder, Colorado. "It's exciting to develop new uses for New Horizons to add to its originally intended uses as the mission continues. The spacecraft and its powerful suite of instruments are in excellent health as the mission continues through the Kuiper Belt. From that perch, New Horizons is in a unique position not only to continue planetary science work, but also to contribute to important studies for astrophysics and heliophysics."

Parker, a longtime member of the New Horizons team, also serves as the project manager for the spacecraft's ultraviolet spectrograph, Alice.

"New Horizons is uniquely positioned to make astrophysical observations that are difficult or impossible to make here on Earth or even from orbit," Parker said. "Many things can obscure observations, but one of the biggest problems is the dust in the inner solar system. It may not be obvious when you look up into a clear night sky, but there is a lot of dust in the inner part of the solar system. There is also a great deal of obscuration at certain ultraviolet wavelengths at closer distances due to the hydrogen that pervades our planetary system, but which is much reduced out in the Kuiper Belt and the outer heliosphere."

The dust results from asteroids, comets, and other objects colliding or shedding dust. As New Horizons has traveled farther from Earth to the Kuiper Belt and beyond, the dust becomes less dense. Additionally, contamination from the Sun and its light scattering off dust and hydrogen gas is diminished near the spacecraft's position at the edge of the solar system.

"It's like driving through a thick fog, and when you go over a hill, it's clear," Parker said. "Suddenly, you can see things that were obscured. When you're trying to look for a very faint light far outside our solar system or beyond our galaxy, that obscuration creates a challenge."

Earth-based observations of objects beyond the solar system must account for interference from dust and light, requiring scientists to estimate how significantly their view is obstructed. The New Horizons team uses the spacecraft's position in the Kuiper Belt to better understand these models' accuracy and make observations without having to make corrections based on dust models.

"If we measure how the 'fog' changes as we move farther out, we can make better models for our observations from Earth," Parker said. "With more accurate models, we can more easily subtract the effects of light and dust contamination."

The New Horizons team is particularly interested in the cosmic optical background and what it reveals about the evolution of galaxies over the history of the universe, including clues about the nature of dark matter. Team members are also interested in observing the cosmic ultraviolet background, which could shed light on star formation rates, interstellar shocks, and dust scattering, as well as improving existing observation models and mapping the hydrogen distribution in the outer heliosphere and nearby parts of the interstellar medium.

"The landmark planetary science New Horizons is doing and continues to do are amazing, but it's also amazing to see the spacecraft contributing significantly to other important fields of science, such as astrophysics and heliophysics," said Alan Stern, the New Horizons principal investigator from SwRI.

SwRI directs the mission via Principal Investigator Alan Stern and leads the science team, payload operations, and encounter science planning. The Johns Hopkins Applied Physics Laboratory in Laurel, Maryland, designed, built, and operates the New Horizons spacecraft and manages the mission for NASA's Science Mission Directorate. The MSFC Planetary Management Office provides the NASA oversight for the New Horizons mission. New Horizons is part of the New Frontiers Program managed by NASA's Marshall Space Flight Center in Huntsville, Alabama.

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