Uncovering Icy Objects in the Kuiper Belt - NASA Science

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Hubble observations of the outskirts of our solar system found a moon orbiting Makemake and several new moons around Pluto. These observations played a critical role in helping NASA plan the New Horizons spacecraft’s flyby of Pluto and beyond. They allowed the mission’s team to refine maps of Pluto’s surface in preparation for the rendezvous with Pluto and its moons.

Hubble observations of Pluto, mapped over spheres

Hubble’s view of Pluto provided NASA’s New Horizons mission with the best available information for planning its rendezvous with the dwarf planet.

NASA, ESA and M. Buie (Southwest Research Institute)

Hubble spied four previously unknown moons orbiting icy Pluto. The tiny moons Nix and Hydra were the first ones Hubble spotted, followed by the even tinier Kerberos and Styx. Astronomers later discovered that Nix and Hydra are rotating chaotically and unpredictably as they orbit the dwarf planet.

Hubble also uncovered two potential Kuiper Belt objects that the New Horizons spacecraft could target on its outward journey past Pluto. On Jan. 1, 2019, New Horizons flew past one of these objects – called Arrokoth – capturing up-close imagery that revealed its double-lobed structure in fine detail, complete with fractures and pitting.

Hubble Discovers a Fifth Moon Orbiting Pluto

Hubble discovered Pluto’s four small moons, Nix, Hydra, Styx, and Kerberos. This is a composite of two images of the Pluto system taken by Hubble in July 2012. The blue areas are from a long exposure used to capture the tiny outer moons, but which greatly oversaturated Pluto and Charon. The dark central vertical band is from a shorter exposure designed to show Pluto and Charon more clearly. The diameters of Pluto and its moons are not to scale.
NASA, ESA, and M. Showalter (SETI Institute)
Hubble also discovered a 100-mile-wide moon in orbit around Makemake, the second-brightest icy dwarf planet in the Kuiper Belt. Makemake is 4.8 billion miles (7.7 billion km) from the Sun and approximately 870 miles (1,400 km) across. Oddly, the moon is as dark as charcoal, while Makemake is as bright as fresh snow.

Hubble Discovers Moon Orbiting the Dwarf Planet Makemake

Only about 100 miles in diameter, the tiny dot above the dwarf planet Makemake seen in this Hubble image is its orbiting moon, nicknamed MK 2.
NASA, ESA, and A. Parker and M. Buie (SwRI)

Hubble Discovers Moon Orbiting Dwarf Planet Makemake Credit: NASA's Goddard Space Flight Center; Producer: Katrina Jackson

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New moons at Pluto

Hubble Discovers a Fifth Moon Orbiting Pluto

The irregularly shaped moon is 6 to 15 miles across and has a 58,000-mile-diameter circular orbit around Pluto.

Comparative brightness of Pluto’s moons

Hubble Finds Two Chaotically Tumbling Pluto Moons

Hubble has discovered tiny satellites orbiting Pluto and Charon.

Hubble's view of the first moon discovered around dwarf planet Makemake

Hubble Discovers Moon Orbiting Dwarf Planet Makemake

Hubble has uncovered a tiny moon around Makemake that is an estimated 100 miles wide.

Three views of Pluto. Three mottled circles in colors of yellow, grey, rusty-orange, and black.

New Hubble Maps of Pluto Show Surface Changes

Hubble's view can't see craters or mountains, if they exist on the surface, but does reveal a complex-looking and variegated world.

Kuiper Belt object (KBO), located on the outer rim of our solar system

Hubble Finds Potential Kuiper Belt Targets for New Horizons

Hubble did a deep-sky survey to identify Kuiper Belt objects that New Horizons could potentially visit on its outbound trajectory.

Hubble Spots Icy World Beyond Pluto

Approximately half the size of Pluto, the icy world is called "Quaoar" is about 4 billion miles away, more than a billion miles farther than Pluto.

Hubble Science Highlights

Discover the breadth and depth of Hubble's exciting discoveries!

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Hubble image left to right: Jupiter, Uranus, Saturn, Neptune

Studying the Planets and Moons

Hubble’s systematic observations chart the ever-changing environments of our solar system's planets and their moons.

animation of a binary asteroid with a shifting tail

Tracking Evolution in the Asteroid Belt

These conglomerates of rock and ice may hold clues to the early solar system.

The Mystic Mountain is seen as a chaotic pillar of colorful gas and dust, narrowing toward the top of the image. The dust and gas is mostly yellow, brown, and orange, all jutting against a hazy purple and blue background with a few pink stars.

Exploring the Birth of Stars

Seeing ultraviolet, visible, and near-infrared light helps Hubble uncover the mysteries of star formation.

Hubble image of the Crab Nebula

The Death Throes of Stars

When stars die, they throw off their outer layers, creating the clouds that birth new stars.

Thirty proplyds in a 6 by 5 grid. Each one is unique. Some look like tadpoles, others like bright points in a cloudy disk.

Finding Planetary Construction Zones

Hubble’s sensitivity uncovers the seeds of planets in enormous disks of gas and dust around stars.

Artist's impression of the ten hot Jupiter exoplanets. Two rows of exoplanet illustrations. There are 5 planets of varying sizes, colors, and atmospheric features in each row.

Recognizing Worlds Beyond Our Sun

Hubble can detect and measure the basic organic components for life on planets orbiting other stars

Hubble view of an expanding halo of light around star v838 monocerotis

Seeing Light Echoes

Like ripples on a pond, pulses of light reverberate through cosmic clouds forming echoes of light.

Hubble Ultra Deep Field image

Tracing the Growth of Galaxies

Hubble's Deep Field observations are instrumental in tracing the growth of galaxies.

Comma shaped curved cloud of gases in bright white edged with bright-pink star forming regions, and threaded with rusty-brown tendrils of dust at center and throughout the comma shaped merger. All set against the black of deep space.

Galaxy Details and Mergers

Galaxies evolve through gravitational interaction with their neighbors, creating a menagerie of forms.

Computer simulation of a supermassive black hole at the core of a galaxy. Center is a black circle. Surrounding the black circle are arcs of red, blue, orange, and white. Further out from the circle are blotches of red, blue, orange, and white representing celestial objects.

Monster Black Holes are Everywhere

Supermassive black holes lie at the heart of nearly every galaxy.

Six Hubble images in a grid of three across and two down. Each is a gamma-ray burst in a host galaxy. The images are orange-red and white with hints of yellow.

Homing in on Cosmic Explosions

Hubble helps astronomers better understand and define some of the largest explosions in the universe.

Cepheid star in Andromeda galaxy (Hubble observations)

Discovering the Runaway Universe

Our cosmos is growing, and that expansion rate is accelerating.

A field of galaxies along with the curved arcs of gravitationally lensed galaxies.

Focusing in on Gravitational Lenses

Gravitational lenses are 'Nature's Boost', expanding our view deeper into space and farther back in time.

A cluster of galaxies fills the frame. A purple glow around the largest concentrations of galaxies indicates the distribution of dark matter.

Shining a Light on Dark Matter

The gravitational pull of dark matter guides the formation of everything we can see in the universe.

Top: Three views going back in time show slices of the cosmos. Bottom: A computer simulated, 3-D map of the distribution of dark matter.

Mapping the Cosmic Web

Filaments and sheets of matter create an interconnected web that forms the large-scale structure of the universe.