Traffic Around Mars Gets Busy

NASA - Deep Space Network patch.

May 5, 2015

Fast Facts:

- Five active spacecraft are orbiting Mars, an increase of two since last summer

- An enhanced system warns if two orbiters may approach each other too closely

NASA has beefed up a process of traffic monitoring, communication and maneuver planning to ensure that Mars orbiters do not approach each other too closely.

Deep Space Network. Image Credits: NASA/JPL
Last year’s addition of two new spacecraft orbiting Mars brought the census of active Mars orbiters to five, the most ever. NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) and India’s Mars Orbiter Mission joined the 2003 Mars Express from ESA (the European Space Agency) and two from NASA: the 2001 Mars Odyssey and the 2006 Mars Reconnaissance Orbiter (MRO). The newly enhanced collision-avoidance process also tracks the approximate location of NASA’s Mars Global Surveyor, a 1997 orbiter that is no longer working.

It’s not just the total number that matters, but also the types of orbits missions use for achieving their science goals. MAVEN, which reached Mars on Sept. 21, 2014, studies the upper atmosphere. It flies an elongated orbit, sometimes farther from Mars than NASA’s other orbiters and sometimes closer to Mars, so it crosses altitudes occupied by those orbiters. For safety, NASA also monitors positions of ESA’s and India’s orbiters, which both fly elongated orbits.

Image above: This graphic depicts the relative shapes and distances from Mars for five active orbiter missions plus the planet’s two natural satellites. It illustrates the potential for intersections of the spacecraft orbits. Image Credit: NASA/JPL-Caltech.

“Previously, collision avoidance was coordinated between the Odyssey and MRO navigation teams,” said Robert Shotwell, Mars Program chief engineer at NASA’s Jet Propulsion Laboratory, Pasadena, California. “There was less of a possibility of an issue. MAVEN’s highly elliptical orbit, crossing the altitudes of other orbits, changes the probability that someone will need to do a collision-avoidance maneuver. We track all the orbiters much more closely now. There’s still a low probability of needing a maneuver, but it’s something we need to manage.”

ISRO Mars Orbiter Mission. Image Credit: ISRO
Traffic management at Mars is much less complex than in Earth orbit, where more than 1,000 active orbiters plus additional pieces of inactive hardware add to hazards. As Mars exploration intensifies, though, and will continue to do so with future missions, precautions are increasing. The new process was established to manage this growth as new members are added to the Mars orbital community in years to come.

All five active Mars orbiters use the communication and tracking services of NASA’s Deep Space Network, which is managed at JPL. This brings trajectory information together, and engineers can run computer projections of future trajectories out to a few weeks ahead for comparisons.

ESA Mars Express. Image Credit: ESA
“It’s a monitoring function to anticipate when traffic will get heavy,” said Joseph Guinn, manager of JPL’s Mission Design and Navigation Section. “When two spacecraft are predicted to come too close to one another, we give people a heads-up in advance so the project teams can start coordinating about whether any maneuvers are needed.”

The amount of uncertainty in the predicted location of a Mars orbiter a few days ahead is more than a mile (more than two kilometers). Calculating projections for weeks ahead multiplies the uncertainty to dozens of miles, or kilometers. In most cases when a collision cannot be ruled out from projections two weeks ahead, improved precision in the forecasting as the date gets closer will rule out a collision with no need for avoidance action. Mission teams for the relevant orbiters are notified in advance when projections indicate a collision is possible, even if the possibility will likely disappear in subsequent projections. This situation occurred on New Year’s weekend, 2015.

NASA 2001 Mars Odyssey. Image Credits: NASA/JPL-Caltech
On Jan. 3, automated monitoring determined that two weeks later, MAVEN and MRO could come within about two miles (three kilometers) of each other, with large uncertainties remaining in the exact passing distance. Although that was a Saturday, automatic messages went out to the teams operating the orbiters.

“In this case, before the timeline got short enough to need to plan an avoidance maneuver, the uncertainties shrank, and that ruled out the chance of the two spacecraft coming too near each other,” Guinn said. This is expected to be the usual pattern, with the advance warning kicking off higher-level monitoring and initial discussions about options.

NASA Mars Reconnaissance Orbiter (MRO): Image Credits: NASA/JPL-Caltech
If preparations for an avoidance maneuver were called for, spacecraft commands would be written, tested and approved for readiness, but such commands would not be sent to a spacecraft unless projections a day or two ahead showed probability of a hazardous conjunction. The amount of uncertainty about each spacecraft’s exact location varies, so the proximity considered unsafe also varies. For some situations, a day-ahead projection of two craft coming within about 100 yards (100 meters) of each other could trigger a maneuver.

The new formal collision-avoidance process for Mars is part of NASA’s Multi-Mission Automated Deep-Space Conjunction Assessment Process. A side benefit of it is that information about when two orbiters will be near each other – though safely apart – could be used for planning coordinated science observations. The pair could look at some part of Mars or its atmosphere from essentially the same point of view simultaneously with complementary instruments.

NASA Mars Global Surveyor. Image Credit: NASA
Odyssey, MRO and MAVEN – together with NASA’s two active Mars rovers, Opportunity and Spirit – are part of NASA’s robotic exploration of Mars that is preparing the way for human-crewed missions there in the 2030s and later, in NASA’s Journey to Mars strategy.

NASA’s Goddard Space Flight Center manages the MAVEN project for the NASA Science Mission Directorate, Washington. MAVEN’s principal investigator is based at the University of Colorado’s Laboratory for Atmospheric and Space Physics. JPL, a division of the California Institute of Technology in Pasadena, manages NASA’s Mars Exploration Program and the Odyssey and MRO projects for the Science Mission Directorate. Lockheed Martin Space Systems, Denver, built all three NASA Mars orbiters.

For more about NASA’s Mars Exploration Program, visit: and

For more information about NASA Mars Atmosphere and Volatile Evolution (MAVEN), visit:

For more information about ISRO Mars Orbiter Mission, visit:

For more information about ESA Mars Express, visit:

For more information about NASA 2001 Mars Odyssey, visit:

For more information about NASA Mars Reconnaissance Orbiter (MRO), visit:

For more information about NASA Mars Global Surveyor, visit:

Images (mentioned), Text, Credits: NASA/JPL/Guy Webster.

Best regards,
Full article

hannah: Surface of Mars, photographed by Mars Express, 25th November 2005.

Image runs from 32°S 201°E about 710 km due south across the Terra Sirenum highlands to 44°S 201°E. The Sirenum Fossae run across the top of the 2nd image. The 5th and 6th images show a central section of the 300 km-wide Newton Crater, including what looks like part of the central peak complex (notice dunes, dark blue, on the left hand side).

Composite of 3 visible light images for colour, and one monochrome image for detail. Colour balance is not naturalistic.

Image credit: ESA. Composite: AgeOfDestruction.

The Syrtis Major Volcanic Province - The Martian Surface

Acquired by the High Resolution Stereo Camera on ESA’s Mars Express Satellite, this image depicts a detailed region of the Martian Nili Fossae Graben system. This system is an area of great interest to geologists due to the variety of its landscape. The graben system contains numerous troughs, plateaus, impact craters and depressions. Planetary Scientists are actively studying the data collected from ESA’s Mars Express through images similar to this.

Credit & Copyright: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO


Mars in 3D

Digital Terrain Models (DTMs) allow scientists to ‘stand’ on planetary surfaces. Although ordinary images can give spectacular bird’s-eye views, they can only convey part of the picture. They miss out on the topography, or the vertical elevation of the surroundings. That’s where Mars Express comes in.

The DTM can instantly tell researchers the slope of hillsides or the height of cliffs, the altitude and slope of lava flows or desert plains. It also helps planetary scientists to better interpret other data sets, for example the results of the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS).

The Mars Express DTM is the most detailed topographic data set ever released for Mars. Its release has been made possible by processing individual image swaths taken by the HRSC as Mars Express sweeps through its orbit. The individual swaths are then put together into mosaics that cover large regions. The high-resolution images used have a resolution of 10 m/pixel. The DTM elevation data derived from these images is provided in pixels of up to 50 m, with a height accuracy of 10 m.

The orbit of Mars Express determines the resolution of its pictures. When it is closest to the surface, it can take the most detailed pictures.

Credit: ESA

Mars’ potato-shaped moon Phobos will be receiving a fly-by of ESA’s Mars Express spacecraft this Sunday! Zipping by 28 feet above its surface, the spacecraft will be traveling too close and too fast for any photo ops, but the science collected from this fly-by will provide the most accurate details yet of the 27 x 22 x 18km moon’s gravitational field, which in turn, will enable us to better understand its internal structure.

“At just 45 km from the surface, our spacecraft is passing almost within touching distance of Phobos…we’ve been carrying out maneuvers every few months to put the spacecraft on track and, together with the ground stations that will be monitoring it on its close approach, we are ready to make some extremely accurate measurements at Phobos.” stated Michael Denis, the Mars Express Operations Manager [source]

As the spacecraft nears Phobos, it will be pulled off course by the moon’s gravity, altering its velocity by a mere few centimeters per second. As these measurements are sent back as radio signals from Mars Express, Earthly scientists will then translate them to determine the mass and and density structure within the moon. This data will assist in addressing questions of origin pertaining to Phobos’ planetary sibling, Deimos, as well.

How does this work? Mars Express possesses a high-resolution stereo camera which has been taking photos of Phobos against the background star field in the previous weeks leading up to this 35 hour tracking sequence: before, during and after the close encounter with Phobos. In addition to researching obtained toward its gravitational field, Mars Express will take measurements on the influence of solar wind on the moon’s surface.

“By making close flybys of Phobos with Mars Express in this way, we can help to put constraints on the origin of these mysterious moons…Mars Express entered orbit around the Red Planet exactly ten years ago this week – this close flyby of Phobos is certainly an exciting way to celebrate!”
- Olivier Witasse, Mars Express Project Scientist at ESA [source]

Phobos’ relative size compared to the Alpes and town of Grenoble, France.

Not so lumpy now, eh?

Excerpts and information from the article ‘Mars Express heading towards daring flyby of Phobos’. For further details on this marvelous spacecraft, ESA put together a 10-year video montage of Mars Express highlights, providing insight into the sophisticated equipment on board, which you can accompany with the 90-minute replay of ESA’s Mars Express conference from June 2013, which highlights the key scientific discoveries of the mission along with a new mineral atlas created to chart the geological history of Mars.

What your birth chart will teach you
  • Sun:Why do I act and express myself the way I do
  • Moon:Why do I react and feel the way I do
  • Ascendent:Why do I see and meet the world the way I do
  • Mercury:Why do I think and communicate the way I do
  • Venus:Why do I express affection the way I do
  • Mars:Why do I express anger and passion the way I do
  • Jupiter:Where do I feel most confident and where do I push my luck
  • Saturn:Where do I feel most anxious and where do I need to realize authority
  • Uranus:Where do I rebel and innovate
  • Neptune:Where do I lose touch with reality and how do I escape it
  • Pluto:Where do I feel most powerless and how do I need to let go of ego to transform
  • Midheaven:What do I want to achieve and who do I want to become
  • Descendent:What do I project on other people
  • Immum Coeli:How has my upbringing affected my psychological roots

gwen: Surface of Mars, photographed by Mars Express, 22nd August 2007.

Image runs southwest from 71°S 56°E, just south of the Dorsa Brevia, to 80°S 34°E, just west of the Promethei Rupes; about 615 km. The dunes (dark blue) in the 4th image are inside Main Crater (Robert Main, astronomer, 1808-1878).

Composite of 3 visible light images for colour, and one monochrome image for detail. Colours are relative, not naturalistic.

Image credit: ESA. Composite: AgeOfDestruction.


Martian Latte - a Mosaic of the South Pole of Mars
Photo by ESA/G. Neukum (Freie Universitaet, Berlin)/Bill Dunford 

The Mars Express orbiter has been circling the fourth rock from the Sun for 10 years now, taking thousands of observations. Bill Dunford collected quite a few of those images and created this jaw-dropping mosaic of the south pole of Mars. It’s not quite what the eye would see; what’s shown as red is actually near infrared, invisible to us but easily seen by the camera on the spacecraft. Kilometers-thick water ice covers the pole, capped itself by a layer of carbon dioxide ice a few meters thick. That is mixed with the rusty dust eternally blowing in the Martian winds, creating what looks more like something you’d order at a coffee shop rather than the frigid nether regions of a nearby world

FROM The Universe in pictures: The best space photos of 2013 by Phil Plait

Mars Express Image of the Martian North Pole
A mosaic of 57 separate pictures, enough to cover the 1,000-kilometer-wide (600-mile-wide) ice cap // Photo by ESA/DLR/FU Berlin (G. Neukum) image processing by F. Jansen (ESA)

On June 2, 2003, the European Space Agency launched the Mars Express probe to the red planet. To celebrate the 10th anniversary of launch, the ESA released this devastating picture of the north polar ice cap of Mars. 

The ice there is mostly water ice, permanently frozen. However, there’s a thin layer of frozen carbon dioxide—dry ice—that coats it every winter and sublimates (turns directly from a solid into a gas) every summer.

That means the ice cap changes all the time, making it a target of study.

From Bad Astronomy

Phobos flies over Mars

Mars Express captured the 6 images in this animation on its orbit 6128 (October 10, 2008) using the Super Resolution Channel of its High Resolution Stereo Camera (SRC). Mars Express was 10,258 kilometers from Phobos when the series of images was taken. Phobos is visible against the backdrop of Mars. Phobos is much darker than Mars; the dark appearance of Mars suggests Phobos is near Mars’ terminator (day-night boundary).

Image Credit: ESA/DLR/FU Berlin (G. Neukum) / Emily Lakdawalla

Mars Express Orbiter Buzzes Martian Moon Phobos

On Sunday, at 5:17 p.m. GMT (12:17 p.m. EST), Europe’s Mars Express orbiter successfully completed a daring low-pass of Mars’ largest moon Phobos. In an effort to precisely measure the gravitational field of the moon, the 10 year-old mission was sent on a trajectory that took it only 45 kilometers (28 miles) from the dusty surface, the closest any spacecraft has ever come to the natural satellite. Read more

Fly through a canyon on Mars

Glide through part of the largest canyon on Mars, Valles Marineris, in this stunning colour movie from ESA’s Mars Express. Valles Marineris is not just the largest canyon on Mars, but at 4000 km long, 200 km wide and 10 km deep it is the largest in the entire Solar System.

The movie focuses on an enclosed 8 km-deep trough in the northern most part of Valles Marineris, called Hebes Chasma. The movie glides over impact craters pockmarking the plains separating the troughs, down cliff faces scarred by landslides, and along the rough valley floor.

In some parts of the valley Mars Express has detected water-bearing minerals, suggesting that significant quantities of water may have once flowed here.

The formation of Hebes Chasma is likely connected to the nearby volcanic Tharsis region, home to the planet’s vast Olympus Mons volcano.

During periods of intense volcanism the whole region stretched upwards, causing tremendous stress in the crust further way. Unable to withstand the strain, the crust ripped open, collapsing into the chasms found in and around Valles Marineris.

Image credit: ESA/DLR/FU Berlin (G. Neukum)

Access the video here.


The intriguing mounds of Juventae Chasma revealed by Mars Express 

Intriguing mounds of light-toned layered deposits sit inside Juventae Chasma, surrounded by a bed of soft sand and dust.

The origin of the chasma is linked to faulting associated with volcanic activity more than 3 billion years ago, causing the chasma walls to collapse and slump inwards, as seen in the blocky terrain in the right-hand side of this image.

At the same time, fracturing and faulting allowed subsurface water to spill out and pool in the newly formed chasm. Observations by ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter show that the large mounds inside the chasma consist of sulphate-rich materials, an indication that the rocks were indeed altered by water.

The mounds contain numerous layers that were most likely built up as lake-deposits during the Chasma’s wet epoch. But ice-laden dust raining out from the atmosphere – a phenomenon observed at the poles of Mars – may also have contributed to the formation of the layers.

While the water has long gone, wind erosion prevails, etching grooves into the exposed surfaces of the mounds and whipping up the surrounding dust into ripples.

The image was taken by the high-resolution stereo camera on ESA’s Mars Express on 4 November 2013 (orbit 12 508), with a ground resolution of 16 m per pixel. The image centre is at about 4°S / 298°E.

Credits: ESA/DLR/FU Berlin (G. Neukum)

te coule un drôle de regard: Surface of Mars, photographed by Mars Express, 23rd December 2008.

1°N to 14°S, 64°E on the Terra Tyrrhena. For scale, Verlaine Crater - divided between the 5th and 6th images - is about 40 km across. The crater at bottom left of the 7th image is only a few degrees north of this gif.

Verlaine Crater is named after Verlaine, a village of about 3,500, rather than the groundbreaking queer poet Paul-Marie Verlaine (1844-1896). Curiously the IAU record the village as being in France, while it appears to be in the largely French-speaking Walloon Region of Belgium.

Composite of 3 visible light images for colour, and 1 monochrome image for detail. 

Image credit: ESA. Composite: AgeOfDestruction.

Battered Tharsis Tholus Volcano On Mars |

The latest image released from Mars Express reveals a large extinct volcano that has been battered and deformed over the aeons.

By Earthly standards, Tharsis Tholus is a giant, towering 8 km above the surrounding terrain, with a base stretching over 155 x 125 km. Yet on Mars, it is just an average-sized volcano. What marks it out as unusual is its battered condition.

Shown in images taken by the HRSC high-resolution stereo camera on the European Space Agency’s Mars Express spacecraft, the volcanic edifice has been marked by dramatic events.

At least two large sections have collapsed around its eastern and western flanks during its four-billion-year history and these catastrophes are now visible as scarps up to several kilometres high. continue reading

Hebes Chasma:This martian abyss, more than 4 times as wide and deep as the Grand Canyon, is an enclosed, almost 8 km-deep trough stretching 315 km in an east–west direction and 125 km from north to south at its widest point. It sits about 300 km north of the vast Valles Marineris canyon.

Chart Cheat Sheet
  • Sun:v much the “self,” or “main character.” Main concerns of the life, vitality.
  • Moon:emotions, instincts, habits.
  • Mercury:communication, type of intellect, reason.
  • Venus:love, beauty, art, and the expression therein.
  • Mars:taking action, aggression (or lack thereof), desire.
  • Jupiter:the way we choose to expand, optimism.
  • Saturn:restriction, pessimism/depression, what kind of structure we need in our lives.
  • Uranus:our daily little rebellions, eccentricities.
  • Neptune:imaginations, dreams, delusions.
  • Pluto:obsessions, transformations, what kind of power we have.
  • North Node:potential.
  • South Node:karmic past.
  • Chiron:how we heal, points of healing.

shannon: Surface of Mars, photographed by Mars Express, 28th October 2005.

Image runs from 63°S 205°E on the Terra Sirenum about 830 km due south to 78°S 205°E among the Ultima Scopuli. The crater seen in the 5th and 6th images is Reynolds (Osborne Reynolds, engineer & physicist, 1842-1912; see also: Reynolds number).

Composite of 3 visible light images for colour, and one monochrome image for detail. 

Image credit: ESA. Composite: AgeOfDestruction.

The Mars Express orbiter captured this stunning view of the north polar
region of Mars
in January, 2012. Credit: ESA/DLR/FU Berlin (G. Neukum)