Hubble observations of asteroids, comets, and dwarf planets 

Max MutchlerResearch and Instrument ScientistSpace Telescope Science InstituteBaltimore, Maryland

Max Mutchler has been working on the Hubble Space Telescope (HST) for the entire 20-year mission, including the final Space Shuttle servicing mission last year. As an expert on Hubble's cameras, Max has been involved in a wide range of scientific observations of the universe.

Many of Max’s Solar System observations with Hubble have supported the planning of other missions. This includes the Dawn mission, currently en route to asteroid Vesta and dwarf planet Ceres, and the Rosetta mission which flew by asteroid Lutetia in July. Asteroid “6815 Mutchler” was named in honor of Max’s discovery of Pluto’s moons, Nix & Hydra, in collaboration with the New Horizons mission, which is currently en route to Pluto. 

Max’s interest in astronomy began while growing up in Racine, Wisconsin. He has degrees in Physics, Astronomy, and Space Science from the University of Wisconsin and Florida Tech. Max is also very active in educational and public outreach, largely because he appreciates the experiences that inspired him to study science when he was young, and he is now in a position to return the favor. Max enjoys showing students how fun and fulfilling scientific research can be, sometimes by engaging them directly in aspects of his research projects. He is also currently planning “citizen science” projects.

Max is also a member of the Hubble Heritage Team, which intentionally strives to produce evocative and iconic images with Hubble, to inspire people with the beauty of their universe, and encourage them to keep abreast of what scientists are learning about it. This recently includes spectacular images from Hubble’s new Wide Field Camera 3, which was installed by astronauts last year.  Max recently began working on Hubble’s successor, the James Webb Space Telescope (JWST).

Hubble Space Telescope

• Hubble servicing missions, and support for planetary missions

• The small bodies of the Solar System: “ready for their close-up”

• Solar System collisions in our past, present…and future

Themes

Hubble was deployed and is serviced by the Space Shuttle

19901993 1997199920022009

Astronaut John Grunsfeld “spacewalking”…he’s now at STScI

Goddard Spaceflight Center…16-hour shift during camera repair and first tests!

HubbleEarlyReleaseObservations:

Solar System feeling left out?

Before we were really ready for it…

Comet Shoemaker-Levy 9 breaks up and impacts Jupiter in

July 1994, shortly after the first Hubble servicing mission

How many other impacts have we missed?

What if Comet SL9 hit Earth instead of Jupiter?

Much less likely, but maybe we should try to understand these events?

Comet 73P/SW3 breaks into many fragments in 2006 Comet 73P/SW3 breaks into many fragments in 2006

BG

Comet 73P/SW3 Fragment B on 18 April 2006Comet 73P/SW3 Fragment B on 18 April 2006

Evolving very rapidly over 3 days: Evolving very rapidly over 3 days: difficult to follow the many fragmentsdifficult to follow the many fragments

Comet 73P/SW3 Fragment B on 19 April 2006Comet 73P/SW3 Fragment B on 19 April 2006

Evolving very rapidly over 3 days: Evolving very rapidly over 3 days: difficult to follow the many fragmentsdifficult to follow the many fragments

Comet 73P/SW3 Fragment B on 20 April 2006Comet 73P/SW3 Fragment B on 20 April 2006

Evolving very rapidly over 3 days: Evolving very rapidly over 3 days: difficult to follow the many fragmentsdifficult to follow the many fragments

Hal Weaver, Max Mutchler, Philippe Lamy, Imre Toth, Casey Lisse, Bill Reach,Jeremy Vaubaillon

Strange eruption of a comet

Hubble: no fragments

Comet Holmes: not particularly close to the Sun or Jupiter at outburst. Might have thought it was a collision, but Hubble saw no fragments…and a similar event happened in 1892.

Comet Tempel 1:Collision on demand

Asteroids and comets visited by spacecraft

Comets: icy, with elliptical

orbits

Comets: icy, with elliptical

orbits

Asteroids: rocky, with

circular orbits between Mars

and Jupiter…

…but there are someicy “Main Belt Comets”,and Near-Earth Objects

Main Asteroid Belt

Water Ice Discovered on Asteroid for First Time By Clara MoskowitzSPACE.com Senior Writer28 April 2010

Water ice has been found on the surface of a nearby asteroid for the first time – a discovery that could help explain how Earth got its oceans.

Two teams of researchers independently verified that the asteroid 24 Themis – a large rock hurtling through space in the asteroid belt between Mars and Jupiter – is coated in a layer of frost. They also found that the asteroid contains organic material, including some molecules that might be ingredients for life.

The discovery might even provide clues about the origin of water on Earth. "Our data are certainly at least consistent with the idea that you could bring in plenty of water from impacts,“ said Andrew Rivkin of Johns Hopkins University.

A comet in the asteroid belt?

No, behaving more like an asteroid collision…

Hubble imaging of Pallas: large asteroid with an impact crater?

The Shape and Surface Variation of 2 Pallas from the Hubble Space TelescopeSchmidt, B. E.; Thomas, P. C.; Bauer, J. M.; Li, J.-Y.; McFadden, L. A.; Mutchler, M. J.; Radcliffe, S. C.; Rivkin, A. S.; Russell, C. T.; Parker, J. Wm.; Stern, S. A.; 2009, Sci, 326, 275 -

Artist’s impression

Hubble imaging of Pallas: large asteroid with an impact crater?

The Shape and Surface Variation of 2 Pallas from the Hubble Space TelescopeSchmidt, B. E.; Thomas, P. C.; Bauer, J. M.; Li, J.-Y.; McFadden, L. A.; Mutchler, M. J.; Radcliffe, S. C.; Rivkin, A. S.; Russell, C. T.; Parker, J. Wm.; Stern, S. A.; 2009, Sci, 326, 275 -

Hubble images of Ceres reveal roundness, surface features, and colors

Three different faces of Ceres

Hubble images of Ceres reveal roundness, surface features, and colors

Three different faces of Ceres

dwarf planet asteroid (small solar system body)

Hey, no fair!

Big collisions in the early Solar System:

Earth-Moon formation

Pluto and moons

Vesta impact: created 50 smaller asteroids,and 20% of meteorites

Vesta’s impact crater,volcanic maria, dry?

Same initial conditions, but different subsequent evolutions…and why aren’t we looking for life on Ceres?

Thomas, P. et al., 2005, “Differentiation of the asteroid Ceres as revealed by its shape”, Nature Letters, Vol 437

Thomas, P. et al., 1997, “Impact excavation on asteroid 4 Vesta: Hubble Space Telescope results”, Science, Vol 277

Vesta color composites, in phase sequence

Hubble WFPC2 images of asteroid Vesta in May 2007: color composite movie

Recent WFC3 images of Vesta helped refine the pole, will help Dawn orbit insertion

Dawn will spend several months in polar orbit around Vesta, before leaving for Ceres.

Over the last 16 years, Hubble observations have helped refine Vesta’s pole position, which can give Dawn extra time to do science, rather than making orbit adjustments.

A more accurate knowledge of the pole position will also help identify when the extreme latitudes will have the best possible solar illumination, and are “ready for their close-up” .

Improved Measurement of asteroid 4 Vesta’s rotational axis orientationJian-Yang Li,, Peter C. Thomas, Brian Carcich, Max J. Mutchler, Lucy A. McFadden, Christopher T. Russell, Stacy S. Weinstein-Weiss, Marc D. Rayman, Carol A. Raymond (Icarus, submitted)

Vesta satellite search

Hill sphere (orbital stability zone)

WF2 PC1

WF3 WF4

With Hubble, we also searched for moons and rings

(arcs), which would have been exciting

to discover, and given Dawn

more to study.

But setting upper limits on what could be orbiting Vesta is

useful too.

Hubble imaging of asteroid 21 Lutetia

An optical “ghost”… not a moon!

Rosetta flyby of asteroid 21 Lutetia on 7 July 2010

Dawn New Horizons

Pluto 2015

Vesta2011

Ceres2015

Waiting for their spaceships to come in…

…2015 will be a very interesting year!

Most collisions happened early in the Solar System’s history, as it was forming

After the Earth cooled, asteroids and comets may have delivered the elements of life….

…and later, caused the largest mass extinction

Fireball over Wisconsin on 14 April 2010: caused by an object only ~1 meter in diameter

NASA's New Asteroid Mission Could Save the Planet By Tariq Malik SPACE.com Managing Editor16 April 2010

President Barack Obama set a lofty next goal this week for Americans in space: Visiting an asteroid by 2025. But reaching a space rock in a mere 15 years is a daunting mission, and one that might also carry the ultimate safety of the planet on its shoulders. "By 2025, we expect new spacecraft designed for long journeys to allow us to begin the first-ever crewed missions beyond the moon into deep space," Obama said. "We'll start we'll start by sending astronauts to an asteroid for the first time in history.“

Astrophysicist John Grunsfeld – a former NASA astronaut who three shuttle missions to fix the Hubble Space Telescope – suggested sending humans to purposely move an asteroid, to nudge the space rock to change its trajectory. Such a feat, he said, would show that humanity could deflect a space rock if one threatened to crash into the planet.

Scientists estimate there are about 100,000 asteroids and comets near Earth, but only about 20,000 are expected to pose any risk of impact. NASA has found about 7,000 of those objects, 1,000 of them flying in orbits that could potentially threaten the Earth in the future, NASA scientists have said. Astronomer Donald Yeomans, head of NASA's Near-Earth Object program office at NASA's Jet Propulsion Laboratory in Pasadena, Calif., said there are about a dozen near-Earth asteroids that could be within reach of manned spacecraft, but most of those are relatively small. To make a crewed mission worth it, the target space rock would likely have to be at least 300 feet (100 meters) wide. For comparison, the space rock that exploded in a magnificent fireball over Wisconsin this week was just 3 feet (1 meter) wide, Yeomans said.

But there are secrets locked away on asteroids that may hold the key to understanding the formation of the solar system. Asteroids are the thought to be the leftover remnants of the solar system's buildings blocks. The organic molecules and compounds on them may offer clues on how life began on Earth, and if it's possible elsewhere in the universe.