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Comets: Siding Spring (C/2013 A1)

Comets: Siding Spring (C/2013 A1)

Post-Comet Spacecraft Status


Recent Comet Siding Spring Images


Siding Spring Images

  • Mars Orbiters 'Duck and Cover' for Comet Siding Spring Encounter
  • View of Comet Siding Spring from Southern Hemisphere
  • NASA Assets Observing Comet Siding Spring
  • Comet Siding Springs' Distance From Mars
  • Artist's concept of comet Siding Spring (C/2013 A1)
  • NEOWISE Checks on Comet C/2013 A1 Siding Spring
  • Hubble Image of Comet Siding Spring
  • Comet Siding Spring C/2013 A1
  • NEOWISE Spies Comet C/2013 A1 Siding Spring
  • A Comet Heads for Mars
Mars Orbiters 'Duck and Cover' for Comet Siding Spring Encounter View of Comet Siding Spring from Southern Hemisphere NASA Assets Observing Comet Siding Spring Comet Siding Springs' Distance From Mars Artist's concept of comet Siding Spring (C/2013 A1) NEOWISE Checks on Comet C/2013 A1 Siding Spring Hubble Image of Comet Siding Spring Comet Siding Spring C/2013 A1 NEOWISE Spies Comet C/2013 A1 Siding Spring A Comet Heads for Mars

Siding Spring: Press Release Images

Flickr: PACA_C/2013 A1 (Siding Spring)


Flickr: Astro Challenges


Mars Observing Certificate Challenge >>
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Comet Siding Spring C/2013 A1 will make a very close flyby of Mars on Oct. 19, 2014. NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data. Credit: NASA/JPL-Caltech
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Recent News

Latest News
read the article 'All Three NASA Mars Orbiters Healthy After Comet Flyby'
All three NASA orbiters around Mars confirmed their healthy status Sunday after each took shelter behind Mars during a period of risk from dust released by a passing comet.
Read More ››
 
read the article 'NASA's Mars Odyssey Orbiter Watches Comet Fly Near'
The longest-lived robot ever sent to Mars came through its latest challenge in good health, reporting home on schedule after sheltering behind Mars from possible comet dust.
Read More ››
 
read the article 'NASA's MAVEN Studies Passing Comet and Its Effects'
NASA's newest orbiter at Mars, MAVEN, took precautions to avoid harm from a dust-spewing comet that flew near Mars today and is studying the flyby's effects on the Red Planet's atmosphere.
Read More ››
 
read the article 'NASA's Mars Reconnaissance Orbiter Studies Comet Flyby'
NASA's Mars Reconnaissance Orbiter, which has sent home more data about Mars than all other missions combined, is also now providing data about a comet that buzzed The Red Planet today (Oct. 19).
Read More ››
 
read the article 'CRISM Prepares For Mars-grazing Comet Siding Spring'
On October 19, a comet that has travelled many billions of miles will come within about 87,000 miles of Mars – about one-third of the distance of the Moon from Earth.
Read More ››
 
read the article 'NASA Prepares its Science Fleet for Oct. 19 Mars Comet Encounter'
NASA's extensive fleet of science assets, particularly those orbiting and roving Mars, have front row seats to image and study a once-in-a-lifetime comet flyby on Sunday, Oct. 19.
Read More ››
 
read the article 'NASA Holds Briefing to Discuss Comet Flyby of Mars Observations'
NASA will host a briefing on Thursday, Oct. 9, to outline the space and Earth-based assets that will image and study a comet from relatively close range to Mars on Oct. 19.
Read More ››
 
read the article 'JPL to Host
NASA will hold a one-day NASA Social for up to 50 of its social media followers on Oct. 13, 2014, at the agency’s Jet Propulsion Laboratory in Pasadena, Calif.
Read More ››
 
read the article 'Preview Comet Flyby Preparations and a Comet-landing Mission'
Social media users are invited to apply for one of up to 50 credentials to attend a one-day NASA Social on Oct. 13, 2014, at the agency’s Jet Propulsion Laboratory in Pasadena, Calif.
Read More ››
 
read the article 'Orbiter Completes Maneuver to Prepare for Comet Flyby'
NASA's Mars Odyssey spacecraft has successfully adjusted the timing of its orbit around Mars as a defensive precaution for a comet's close flyby of Mars on Oct. 19, 2014.
Read More ››
 
read the article 'NASA's Mars Spacecraft Maneuvers to Prepare for Close Comet Flyby'
NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data, as Comet C/2013 A1 Siding Spring heads toward a close flyby of Mars on Oct. 19.
Read More ››
 
read the article 'NASA's Swift Satellite Tallies Water Production of Mars-bound Comet'
In late May, NASA's Swift satellite imaged comet Siding Spring, which will brush astonishingly close to Mars later this year.
Read More ››
 
read the article 'NASA's Hubble Space Telescope Spots Mars-Bound Comet Sprout Multiple Jets'
NASA released Thursday an image of a comet that, on Oct. 19, will pass within 84,000 miles of Mars -- less than half the distance between Earth and our moon.
Read More ››
 
read the article 'NASA Preparing for 2014 Comet Watch at Mars'
A close flyby of Mars in 2014 by comet Siding Spring could deliver opportunities for learning, but also possible hazards for orbiting spacecraft. NASA is preparing for both.
Read More ››
 
read the article 'Collision Course? A Comet Heads for Mars'
A comet is heading for Mars, and there is a chance that it might hit the Red Planet in October 2014. An impact wouldn't necessarily mean the end of NASA's Mars program, but it would transform the program along with Mars itself.
Read More ››
 
read the article 'Comet to Make Close Flyby of Red Planet in October 2014'
Latest observations indicate comet 2013 A1 will pass within 186,000 miles (300,000 kilometers) of Mars on Oct. 19, 2014.
Read More ››
 

Views of Mars and Comet Siding Spring

This graphic depicts the orbit of comet C/2013 A1 Siding Spring as it swings around the sun in 2014. On Oct. 19, the comet will have a very close pass at Mars, just 82,000 miles (132,000 kilometers) from the planet.

Mars and Comet Siding Spring Animation


Chart of the Science Observations

Multimedia

Comet Siding Spring Videos
read the article 'Observing Comet Siding Spring at Mars'
 
On October 19, Comet Siding Spring will pass within 88,000 miles of Mars - just one third of the distance from the Earth to the Moon! Traveling at 33 miles per second and weighing as much as a small mountain, the comet hails from the outer fringes of our solar system, originating in a region of icy debris known as the Oort cloud. Comets from the Oort cloud are both ancient and rare. Since this is Comet Siding Spring's first trip through the inner solar system, scientists are excited to learn more about its composition and the effects of its gas and dust on the Mars upper atmosphere. NASA will be watching closely before, during, and after the flyby with its entire fleet of Mars orbiters and rovers, along with the Hubble Space Telescope and dozens of instruments on Earth. The encounter is certain to teach us more about Oort cloud comets, the Martian atmosphere, and the solar system's earliest ingredients. Credit: NASA/GSFC
Watch Video ››
read the article 'NASA's Mars Odyssey Maneuvers to Image Comet Siding Spring'
 
Mars program Chief Engineer Robert Shotwell describes Mars Odyssey's unprecedented view of comet Siding Spring as the comet sweeps by the Red Planet on Oct. 19 and how it will maneuver to take images.
Watch Video ››
read the article 'Comet Siding Spring Wide Shots'
 
This visualization show MAVEN and Comet Siding Spring making their way through the solar system to a close encounter near Mars. This animation moves the camera in a bit closer and more parallel with the ecliptic plane as the comet and MAVEN encounter the Martian region. Credit: NASA/GSFC/SVS
Watch Video ››
read the article 'Comet Siding Spring Wide Shots (Fixed)'
 
This visualization show MAVEN and Comet Siding Spring making their way through the solar system to a close encounter near Mars. This animation maintains a fixed camera above the ecliptic plane of the solar system. Credit: NASA/GSFC/SVS
Watch Video ››
read the article 'Comet Siding Spring: A Close Encounter with Mars'
 
Comet C/2013 A1 Siding Spring will make a close flyby of Mars on Oct. 19, 2014. At a distance of only 87,000 miles - about 1/3 the distance between the Earth and moon - it's a near miss of the Red Planet. Find out how NASA's Mars orbiters will evade dust from the comet.
Watch Video ››
read the article 'Animation of Comet Siding Springs’ Close Encounter With Mars'
 
Comet Siding Spring C/2013 A1 will make a very close flyby of Mars on Oct. 19, 2014. NASA is taking steps to protect its Mars orbiters, while preserving opportunities to gather valuable scientific data.
Watch Video ››
 

Comet Siding Spring Encounter at Mars Timeline (Scroll Down)

 

Comet Siding Spring Encounter at Mars Timeline

*Dates and times are in UTC.
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Several weeks prior to closest approach

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July 2

Mars Reconnaissance Orbiter (MRO) orbit maneuver to put spacecraft behind Mars (1st of 2)

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August 5

Odyssey orbit maneuver to put spacecraft behind Mars

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August 6

Mars Reconnaissance Orbiter (MRO) CRISM/HiRISE stellar scan to check boresite

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August 11

1st Comet Siding Spring workshop.
Watch Archived Workshop >>.

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September 19

2nd Comet Siding Spring workshop.
Presentations

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September 21

MAVEN Orbit Insertion.(September 21, 10pm EDT)

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September 24

Opportunity will take a test PanCam image of twilight sky

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September 24

India's Mars Orbit Mission (MOM) Orbit Insertion

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September 25

Mars Reconnaissance Orbiter (MRO) orbit maneuver to put spacecraft behind Mars (2nd of 2)

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October 7

Mars Reconnaissance Orbiter (MRO) HIRISE imaging of comet.

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October 8

Curiosity will take a test Mastcam image of the twilight sky

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10 days to closest approach

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October 9

MAVEN last course correction to put spacecraft behind Mars at time of peak flux.

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October 12 and later

Curiosity and Opportunity may image comet at night.

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October 13

Curiosity will take test spectral images with Mastcam and Chemcam

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October 15

Opportunity will do a dry run of comet imaging, aimed at the comet (although the comet may not be bright enough to detect against the dusty night sky).

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5 days to closest approach

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October 17

MAVEN will image the comet with the IUVS.

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October 17-19

Mars Reconnaissance Orbiter (MRO) (HiRISE, CRISM, CTX) will image the comet.

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October 17-19

MAVEN will monitor the Mars upper atmosphere and solar wind (IUVS, SEP, SWIA, SWEA, STATIC, MAG, LPW, NGIMS).

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October 17-19

Curiosity may image comet at night using the ChemCam, Mastcam.

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2 hours before closest approach

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October 19

Opportunity may image the comet with PanCam.

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October 19

Mars Reconnaissance Orbiter (MRO) imaging of the comet (CRISM, HiRISE, CTX).

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October 19

Mars Reconnaissance Orbiter (MRO) (MCS, MARCI, SHARAD) will monitor Mars' atmosphere.

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October 19

Odyssey (THEMIS) imaging of the comet. Thermal IR and visible imaging of the coma.

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October 19

MAVEN goes into planned "minimum risk" mode ~45 min prior to Closest Approach. LPW, SEP, MAG continue to operate.

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During closest approach

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October 19 11:27 a.m.
PT/2:27 p.m. ET/18:27 UT

Comet Siding Spring (C/2013 A1) Closest Approach to Mars at 87,000 miles (139,500 kilometers).

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October 19

Mars Reconnaissance Orbiter (MRO) imaging of the comet (CRISM, HiRISE, CTX). Comet nucleus may be a few pixels wide in the image

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After closest approach

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October 19 closest approach + 20 minutes

Mars will skirt the comet coma.

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October 19 closest approach + 90 minutes

Odyssey will take several thermal IR and visible images of the comet and tail

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October 19 closest approach + 90 minutes

Mars Reconnaissance Orbiter (MRO) (CRISM and HiRISE) to image the nucleus and CTX rides-along. Other instruments (MCS, MARCI, SHARAD) take observations of Mars' atmosphere to identify atmospheric interactions with comet particles.

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October 19 closest approach + 2.5 hours

Curiosity may image comet at night using the ChemCam, Mastcam.

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October 19 closest approach + 2.5 hours

MAVEN will leave "minimum risk" mode. Spacecraft and instrument status will be checked over the next orbit, then science observations of Mars will resume, to get "after the comet" observations.

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October 19 closest approach + 5 hours

Mars Reconnaisance Orbiter (MRO) (HiRISE, CRISM, CTX) will image the comet.

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October 19 closest approach + 10 hours

Opportunity may image the comet using the PanCam.

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October 20

Opportunity and Curiosity may image the comet after closest approach.

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October 20

Spacecraft will begin to report back to Earth their health and safety status (this schedule is still uncertain on which spacecraft will call home first).

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October 20 - 21

Mars Reconnaisance Orbiter (MRO) (MCS, MARCI, SHARAD) monitors the Mars' atmosphere.

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October 20 - 21

MAVEN will resume atmospheric science (IUVS, SEP, SWIA, SWEA, STATIC, MAG, LPW, NGIMS)

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October 21

Odyssey (THEMIS) images the comet with planet limb.

*Descriptions are current as of 10-7-14 but are subject to change.

Comet Siding Spring Facts

Discovery

Discovery

This comet sneaked up on us because it was coming in from underneath the plane of Earth's orbit!

Luckily, asteroid and comet hunter Robert H. McNaught spotted it with the constellation Lepus in the star background.

At the time of its discovery, Comet Siding Spring
was farther from the Sun than Jupiter -
about 7.2 times farther away from the Sun than Earth.

McNaught achieved this triumph on January 3, 2013, using the 0.5-meter (20-inch) Uppsala Schmidt Telescope, at Siding Spring Observatory in New South Wales, Australia.

Anatomy of Comet Siding Spring (C/2013 A1)

DUST TAIL
NUCLEUS
COMA
ION TAIL
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Dust Tail

Comet Siding Spring's dust tail will completely engulf the entire planet when Mars travels through it. Hubble images show Comet Siding Spring has passed the snow and water lines, the points at which the Sun's warmth activates or releases gases and water ice to form the coma and tail.

Gas and dust in the comet's nucleus and coma often separate into two parts of the comet's tail. A comet's dust tail is the trail of dust and gas illuminated by the Sun. It is blown away from the comet's coma by the solar wind, and follows the curve of the comet's orbit.

When comets are traveling through the outer solar system, they are frozen and do not have tails. Far away and extremely small, they are almost impossible to detect. As they approach the Sun in the inner solar system, radiation from the Sun turns some comet materials like water ice into a gas. As gases leave the nucleus, they carry comet dust with them.

When sunlight illuminates the coma and tail as the comet approaches the Sun, astronomers have a better chance of detecting it.

Nucleus

Though early estimates suggested the size of comet Siding Spring's nucleus could be anywhere from 0.62 to 31 miles (1 to 50 kilometers) across, new data from NASA's Swift Satellite indicates that the icy nucleus of comet Siding Spring is only about 2,300 feet (700 meters) across. Hubble images of Comet Siding Spring show two jets coming from the icy nucleus in opposite directions. Measuring them can help us understand how the comet is rotating and what it might look like when it flies by Mars.

The nucleus is the solid, frozen core of a comet. It is made of rock, dust, water ice, and frozen gases (e.g., carbon dioxide, carbon monoxide, methane, and ammonia).

The nucleus of a comet is usually small in size, usually about a few miles across.

The surface of a comet's nucleus is often dry, dusty, rocky, and dark. Dark materials may contain organic compounds, the chemical building blocks of life. When a comet absorbs heat from the Sun, the nucleus releases water ice and frozen gases.

Sometimes, dazzling jets of gas can erupt from inside the nucleus when the Sun heats some parts of its surface more than others. That can cause the nucleus to spin or even break up into smaller pieces. Such events can change a comet's trajectory and, ultimately, its fate.

Coma

Comet Siding Spring has crossed the snow and water lines, key points when it is close enough for the Sun's warmth to activate it. Now that scientists can see the coma, they estimate it is roughly 12,000 miles (19,000 kilometers) across.

A comet's coma is the atmosphere of gas and dust around the nucleus of the comet. It can be hundreds of thousands of kilometers wide.

The coma of a comet is made largely of water and dust. When a comet approaches the Sun, it warms up. Heat from the Sun changes the comet's icy materials to gases. The comet releases these gases, forming the coma.

Radiation from the Sun and the solar wind then push a lot of this material away from the nucleus, forming the comet's tail.

When a comet is about the same distance from the Sun as Mars (about 1.5 AU), its coma can shrink, even though it is producing more gas as it warms. That's because the solar wind becomes forceful enough to push more coma material into the tail, making the tail a lot bigger.

That can be a big deal for planets like Mars, which is crossing through the debris field of Comet Siding Spring's coma and tail.

Ion Tail

Scientists will study Comet Siding Spring's ion tail to assess any effect ion-tail particles might have on Mars and Mars missions.

Comets usually have two tails-a dust and an ion tail.

The ion tail is made of ionized gas. (You've heard of solid, liquid, and gas, but there's a fourth state: ionized gas, or plasma. Think of plasma screens, fluorescent and neon lights, and even the Northern Lights). Gas becomes ionized when electrons are charged enough to escape atoms or molecules. That always causes a glow of some kind.

Gas in a comet becomes ionized when ultraviolet radiation from the Sun interacts with the comet's gases. A comet's ion tail is usually blue in color due to the gas molecules that make it up. Ionized gas gets blown away from the coma by the solar wind. A comet's ion tail always points away from the Sun.

 

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