Mars Reconnaissance Orbiter (MRO) performed a flawless engine burn today in a successful bid to enter orbit around Mars. The event, known as Mars Orbital Insertion (MOI), is a risky one for robotic visitors to the Red Planet. Now that MRO is safely in orbit, the spacecraft will soon begin several months of aerobraking to reshape the orbit into a circle approximately 300 km above the martian surface. The primary science phase of the mission will begin in the fall after aerobraking has been completed.

At the University of Arizona, an audience of students, the public, reporters, and other guests watched live NASA TV coverage of the event. The High Resolution Imaging Science Experiment (HiRISE) camera is one of the instruments on board MRO and is operated by a team at the University of Arizona. HiRISE Principal Investigator Alfred McEwen and operations team members were on hand for presentations, narration of the television coverage, and answers to audience questions. [Disclosure: Richard Leis is a HiRISE operations team member.]

The risks of any orbital insertion include missing the target altogether or coming in too closely. During MRO MOI, all predicted events occurred on schedule, including the loss of signal from the spacecraft while it passed behind Mars. Reacquisition of the signal from MRO occurred at around 3:15 pm Mountain Standard time, and a few minutes later flight operations at the Jet Propulsion Laboratory in Pasadena, California, USA confirmed that the spacecraft was in the correct initial orbit around Mars. The audience and HiRISE team applauded and cheered the successful conclusion of each major event.

MRO launched from Cape Canaveral in Florida, USA on August 12, 2005. During its 7 month cruise to Mars, instruments on board were turned on and tested in preparation for future science gathering. HiRISE, for example, snapped high resolution images of the moon and stellar clusters. These images are now being used by the operations team to calibration the instrument and develop imaging processing software and procedures.

MRO will remain in its current orbit for about two weeks prior to the start of aerobraking. During that two weeks, some of the operations teams for the various instruments will again turn on their instruments. HiRISE will take nine images of Mars and once again the operations team will use these images for further calibration and testing.

Aerobraking occurs when MRO dips down into the martian atmosphere to create friction that helps slow down the spacecraft and lower its orbit. The process will take from five to seven months depending on the condition of the martian atmosphere on any given day.

After aerobraking, MRO will into a transition orbit during which time the instrument teams will complete their preparations for the primary science phase of the mission. Know as PSP, this phase of the mission will last for two years while scientific data is gathered.

The HiRISE camera is the largest such device ever sent outside the Earth’s orbit. The camera will capture high resolution images of the martian surface, up to 20,000 by 60,000 pixels in size. These images are so huge that they will not fit full size on a regular computer monitor. Only a display array of 20 by 60 monitors would have enough pixels available to show one full-sized HiRISE image. Because of this, recent compression and delivery technology known as JPEG2000 is being used to allow the scientific community and the public to browse through these images over the internet.

At its best setting, HiRISE will be able to see objects roughly one meter (approximately one yard) in size. Meanwhile, two other cameras will take lower resolution images but provide more coverage of the planet. Together, these cameras should reveal a different Mars than shown by previous orbiters, simply because so much more detail and wider coverage will become available than ever before. In fact, so much data will be obtained during the course of the mission that it will dwarf what many previous missions have obtained, combined.

MRO is also equipped with a sounding radar called SHARAD (Shallow Radar) which will return the highest resolution data of the martian subsurface. In recent years, previous spacecraft have detected the presence of water deposits beneath the surface of Mars. SHARAD will attempt to better quantify the amount of water present and in what form – ice or liquid – it exists.

Scientists hope to learn where the water believed to have existed on early Mars went, in what form it exists today, and if water might still flow on the surface (as appears to be the case with gullies discovered by previous spacecraft.) They also hope to learn more about the martian atmosphere and surface history. The information obtained could help determine whether or not Mars has ever been hospitable to life and which locations are best to search for fossil or current lifeforms.

More Information

• Mars Reconnaissance Orbiter (MRO)
• The view from MRO.
• HiRISE
  • HiRISE Presentation (Powerpoint file)
  • Mars Mania II - Saturday, April 08, 2006 at the University of Arizona campus

The modern robotic investigation of comets began with a spacecraft from the European Space Agency (ESA) named Giotto. Giotto captured in 1986 the first close-up images of a cometary nucleus and a wealth of other data. ESA is marking the 20th anniversary of Giotto’s successful flyby of Comet Halley on the eve of a NASA press conference regarding science results from the Stardust mission. Twenty years after Giotto, our knowledge about comets, those cold remnants of our solar system’s formation, is undergoing a revolution.

By 1986, six spacecraft were ready for an unprecedented scientific investigation of Comet Halley as it returned to the inner solar system. Due to budget cuts, NASA’s ambitious plans to study Comet Halley were reduced to long distance observations using the International Sun-Earth Explorer 3 (ISEE-3) spacecraft (renamed Interplanetary Comet Explorer (ICE)) already in operations. Meanwhile, after flying by Venus, the Russian Space Research Institute (IKI) spacecrafts VEGA-1 and VEGA-2 were directed toward Comet Halley. Japan’s Institute of Space and Aeronautical Science, which in 2003 became part of Japan Aerospace Exploration Agency (JAXA), used their existing SAKIGAKE (MS-T5) spacecraft for long distance observations and launched SUISEI (PLANET-A), a spacecraft specifically built to study Comet Halley. ESA’s Giotto spacecraft rounded out “Halley Armada.”

Named after the painter of “Adoration of the Magi” which includes a representation of a comet widely believed to be based on Comet Halley, Giotti flew closer to the comet than any of the other spacecraft. The dramatic images and other data returned revealed that Halley was not a round and icy “snow ball” as expected but instead an irregular and dark “dirt ball.” Jets of ice and gas volatiles erupted from the sun-heated surface of the nucleus, creating the bright and extensive coma and tail visible from the Earth.

This first close-up look at a comet revolutionized our understanding of the objects. Since then, several other robotic missions have provided even more highly detailed images and data. Tomorrow, scientists will hold a press conference to report the first science results from their analysis of the first pristine cometary material returned to Earth for extensive analysis. What we learn from the Stardust mission will no doubt radically advance our knowledge.

In twenty years, from the first close-up images of a comet to the first cometary material returned for study, we have learned more about the formation of our solar system and perhaps even the history of life on Earth than in all the thousands of years of comet observation that preceded the Space Age. From Giotto to Stardust in the blink of an eye.

More Information

• ESA Press Release - “Giotto’s brief encounter“
• Halley Armada:
  • Interplanetary Comet Explorer (ICE)
  • SUISEI (PLANET-A)
  • SAKIGAKE (MS-T5)
  • VEGA-1 and VEGA-2
  • Giotto
• Stardust
  • Press Conference, Monday, March 13, 2006 - “NASA ANNOUNCES FIRST STARDUST COMET SAMPLE RESULTS” | Announcement | NASA TV

Cassini-Huygens mission scientists discovered last year that plumes of ice erupt from the surface of Saturn’s moon Enceladus, but the mechanism for the this process has not been fully explained. Now a review of competing theories and available data implicates the more unlikely source: pressurized liquid water pools or an ocean near the moon’s surface. How water can be liquid on an apparently frozen body in the cold of the distant solar system is just the latest mystery regarding Enceladus.

Several research papers regarding recent findings about Enceladus are available in the March 10, 2006 issue of Science. In a Research Article entitled “Cassini Observes the Active South Pole of Enceladus”, Dr. Carolyn Porco, Cassini imaging team leader at Space Science Institute in Boulder, Colorado, USA and other mission scientists suggest that “water vapor probably venting from subsurface reservoirs of liquid water” provides the source for the majestic surface plumes discovered last year. In turn, these plumes may continually replenish Saturn’s E-ring.

Enceladus become just the fourth object in the solar system suspected of containing liquid water reservoirs because of tantalizing new evidence. Only Earth is known for certain to have liquid water on and below its surface. Evidence for liquid water aquifers on Mars and an ocean deep beneath the ice on Jupiter’s moon Europa have already led to excitement within the scientific community over the past decade. Now that Enceladus has been added to list, the mystery of processes that lead to liquid water only deepens.

If pools or oceans of liquid water exist on Enceladus, where do they come from? A heating source is required to raise the temperature to above 273 degrees Kelvin (0 degrees Celsius.) Mission scientists suspect flexing of the moon caused by its orbit around Saturn or a gravitational tug-of-war between Titan and Saturn, along with radioactive decay within the moon’s interior lead to heating that locally heats crustal water ice. Under pressure, this liquid water eventually escapes to the surface as geysers near the moon’s south pole.

The region near Enceladus’ south pole is striking for its so-called Tiger Stripes, enormous gashes across the surface that a significantly more warm than the surrounding terrain. The lack of craters and the apparent youth of ice in the area all suggest recent resurfacing. The discovery of the ice plumes confirmed this observation.

Mission scientists will continue to sift through the data returned by Cassini to investigate Enceladus. Cassini is currently scheduled to return for a close flyby of Enceladus on Wednesday, March 12, 2008 after a mission focus on Titan over the next two years has concluded.

More Information

• Cassini-Huygens Website
  • NASA/JPL News Release, March 09, 2006 - “NASA’s Cassini Discovers Potential Liquid Water on Enceladus“
  • Saturn’s Moons section
  • Enceladus Information

Mars Reconnaissance Orbiter (MRO) is scheduled for Mars Orbital Insertion (MOI) on Friday, March 10, 2009. Confirmation of success should arrive around 3:15 pm MST. Below is a link to a presentation I gave one of my classes today about the High Resolution Imaging Science Experiment (HiRISE) on board MRO, the highest resolution camera every sent on a planetary science mission. [Disclosure: Richard Leis is a HiRISE operations team member.] All of the spacecraft primary science mission cameras are shut down and will not be turned on until after orbital capture, but I have also included a link to a webpage that updates every 5 minutes a simulation of how Mars would look if you were riding along on MRO. Mars is getting close!

• HiRISE Presentation(Powerpoint file) attached to this article
• The view from MRO.

Astronomers from the European Southern Observatory (ESO) announced today the discovery of an exoplanet only 5.5 times the mass of the Earth orbiting a red dwarf star located near the center of the Milky Way galaxy, some 20,000 light years away from our own solar system. The discovery could indicate that rocky planets like the Earth are common throughout the universe.

The discovery of the exoplanet is only the third using a technique called gravitational microlensing. Microlensing is a faint but detectable brightening of light from a more distant object caused by gravitational lensing by a nearer object passing directly in front of it as seen from the Earth. Microlensing does not provide a direct visual observation of intervening bodies but instead indicates their presence indirectly.

A network of robotic telescopes monitors the galaxy 24 hours a day, 7 days a week, looking for microlensing events. Using the Danish 1.54m telescope at ESO La Silla, Chile, astronomers detected a microlensing event on July 11, 2005 by an intervening star less massive than our own Sun. Immediately after the event was detected, notification went out across the network to provide constant coverage of the phenomena. Ten days later, an anomaly in the wanning microlensing effect indicated the presence of a planet.

The planet has been labeled OGLE-2005-BLG-390Lb after the designation for the microlensing event. Astronomers speculate that the planet is cold and probably contains a significant amount of ice in its composition due to its location approximately three times as far from its parent star as the Earth is from the Sun. Its size is sufficient to hold a substantial atmosphere but such an environment may not be hospitable to life as we know it.

According to NASA’s “Planet Quest” site, 159 exoplanets have been detected to date, although other sources give a number closer to 170. Only one other rocky exoplanet candidate has been discovered and only one exoplanet has been directly imaged. Space agencies and astronomers are developing improved telescopes, spacecraft, and techniques to accelerate the detection and direct imaging of Earth-sized exoplanets over the next decade. The improved technologies may also allow scientists to look for evidence of biological markers in the atmospheres of exoplanets to determine the extent of life in our galaxy.

More Information

• Scientific Paper: Nature Letter, J.-P. Beaulieu, et. al., “Discovery of a cool planet of 5.5 Earth masses through gravitational microlensing“, Nature 439, 437-440 (26 January 2006) | doi:10.1038/nature04441
• European Southern Observatory (ESO)
  • Press Release – January 25, 2006 – “It’s Far, It’s Small, It’s Cool: It’s an Icy Exoplanet!“
  • Video: ESO PR Video 03a/06
• United States National Science Foundation
  • Press Release - January 25, 2006 - “Closer to Home“
  • Images and Video
• Technology - Microlensing events are rare and last only a short time (generally days.) Therefore, networks of robotic telescopes have been set up to automate observation and provide continuous coverage during an event.
  • Probing Lensing Anomalies NETwork (PLANET)
  • RoboNet-1.0
  • The Optical Gravitational Lensing Experiment (OGLE)
  • Microlensing Observations in Astrophysics (MOA)
• Planet Quest - the search for another Earth

The United States Geological Survey (USGS) National Earthquake Center has unveiled upgraded technology, 24/7 staffing, and a new website to be rolled out over the next few months in response to the 2004 Indian Ocean tsunami and a wider call for better earthquake monitoring. The effort includes HYDRA, a system that will provide more detailed information about earthquakes and their potential for damage based on the region affected. HYDRA is expected to be completed in March 2006.

By providing staffing for operations around the clock, the USGS hopes to provide more timely information about earthquakes soon after they occur. The existing website, located at http://earthquake.usgs.gov, already provides maps, news and an RSS feed about recently detected earthquakes from around the world. A redesign set to debut at the end of January 2006 will enhance the site with information from the new monitoring system.

Emergency appropriations and congressional funding for the effort came last year after the magnitude 9.0 Sumatra Earthquake and tsunami that followed killed nearly 300,000 people on December 26, 2004 in one of the worst natural disasters in recent history. Experts believe that monitoring equipment in the Indian Ocean and improved notification technology could have helped prevent many of these deaths. Although the USGS detected the earthquake immediately after it occurred, they were unable to track down the appropriate authorities in countries in the affected region. Earthquake monitoring equipment and notification already exist for the Atlantic and Pacific oceans.

Earthquakes occur at boundaries where the plates that make up the Earth’s lithosphere and crust collide with, separate from or scrape past each other, as well as localized areas of instability caused by volcanic activity, faulting, and other phenomena. In the United States, 39 states are considered to be at some significant risk of earthquakes. The increasing number of people who live in earthquake prone regions will require continued improvements in current monitoring and notification technologies.

More Information

• USGS Earthquake Hazards Program
  • 01/19/2006 USGS Press Release - “USGS National Earthquake Center goes 24/7 — Staff now on-site night and day to locate and report worldwide quakes“

Planetary scientists long assumed that the moons of the outer planets were cold, dead, and airless worlds, heavily cratered but otherwise little changed from their original formation. In 1979, Voyager 1, looking back just after its flyby of Jupiter, discovered volcanic activity on Jupiter’s moon Io. Over a year later, Voyager 1 discovered that the atmosphere of Saturn’s moon Titan, first detected in 1944 by Gerard Kuiper, was thicker than the Earth’s, orange, and opaque. When Voyager 2 passed by Neptune’s moon Triton in 1989, it snapped images of geysers erupting despite the extreme cold.

After Galileo toured the Jovian system during the 1990s and early 2000s, planetary scientists views had been irreversibly changed. Gone was a bias for current geological activity only on Earth, replaced with a stunned awareness of just how dynamic our solar system remains after its formation 4.5 billion years ago. By the time Cassini-Huygens entered the Saturnian System in June 2004, expectations were high for new discoveries of current activity to rival those made by the Galileo spacecraft. A year and a half later, these expectations have been exceeded.

With the advanced remote sensing capabilities offered by Cassini, and the successful landing of the Huygens probe, Titan was revealed to be a world more Earth-like than any other yet discovered. Nearly all geological activities present on the Earth appear to have counterparts on Titan. On Titan are low-lying boundaries that look like shorelines, river channels cut out by the recent activity of liquid methane, snow made of clumps of hydrocarbons, and sand dunes that stretch for hundreds of kilometers. Other features look like volcanoes, lakes, and craters (so few that just like the Earth the surface of Titan must be very young.)

The overwhelming realization that Titan was very much like a planet in its own right could not prepare scientists for what came next.

There was another bias at work, one that seemed more like common sense. All the current geological activity discovered in the solar system to date had been on the largest moons, moons nearly as large or much larger than our own. Of these moons - the giants Ganymede, Callisto, Titan, or Luna-comparable Io, Europa, and Triton – only the Earth and Callisto appear to have ancient surfaces unchanged by current geological activity. Smaller moons, and there are many of them, simply do not have the internal energy or structure to support activity. More recent missions had confirmed what was simply common sense. They were the cold, dead, and airless bodies originally assumed by planetary scientists. Even if they were just large enough to be round, the history of activity could be traced to their early formation and rare impacts on their surfaces.

The Saturn moon Enceladus was observed by Cassini as part of its tour of the system. The tiny moon is only 512 kilometers (318 miles) in diameter, with just over the mass expected by theory to lead to roundness instead of irregularity. The first images revealed that the surface was not heavily cratered or ancient as expected by scientists. Instead, the surface appeared to be very young, especially near the south pole.

Other instruments observed Enceladus during these early flybys. Strange surface features labeled the “Tiger Stripes” were warmer than the surrounding terrain. The ice here was incredibly young, perhaps as young as yesterday. Just as surprising was the localized presence of a thin water vapor atmosphere, around a body that was simply too small to hold one.

All of these discoveries were leading somewhere. In images captured by Cassini in November 2005, revealed in a press release on December 6, 2005, were the smoking guns: the plumes of Enceladus. Stretching higher into space than the moon is wide, the plumes erupt with fine particles of water ice from the Tiger Stripes region of Enceladus. Some of these fall onto the surface of the moon, keeping it young, but the rest contribute something surprising to the Saturnian system: Saturn’s own E-ring.

Enceladus has become the first tiny moon to join the Earth, Io, and Triton as worlds known to have current and active volcanic activity. The exact process that drives this activity on Enceladus is still unclear. Scientists believe the tug of war between Titan and Saturn with Enceladus in the middle induce internal friction below the moon’s surface. They are unsure if this results in a partially melted mantle near Enceladus’ south pole, and whether or not this material erupts as liquid water that quickly freezes, or as already frozen water ice particles. What they can be certain of is that their preconceived notions about small moons were wrong.

Expecting one active moon, Cassini mission scientists discovered a second. New raw images returned by Cassini just last week reveal this activity with breathtaking beauty. The high haze layers of Titan seen through Saturn’s rings is a study in detail. And then there is tiny Enceladus, dwarfed by its parent planet and some of its sibling moons, but magnificent with is brilliant and angry plumes in the sunlight. There is certainly scientific data in these images to be categorized and analyzed by scientists when the raw images are cleaned up, but there is also artistic value to be enjoyed.

Walt Whitman wrote about a scientific lecture in a poem entitled “When I Heard the Learn’d Astronomer.” During the lecture, full of facts and data, Whitman writes:

“How soon, unaccountable, I became tired and sick;
Till rising and gliding out, I wander’d off by myself,
In the mystical moist night-air, and from time to time,
Look’d up in perfect silence at the stars.”

There is a great deal that can, has, and will be said about these and other images from Cassini. First, however, these images may invoke in some Walt Whitman’s perfect silence, not through annoyance or boredom, but instead through great awe and wonder. This is a silence that means one cannot, for the moment, speak. One instead simply appreciates.

More Information

• Cassini-Huygens Website
  • NASA/JPL/Space Science Institute Press Release - “NASA’s Cassini Images Reveal Spectacular Evidence of an Active Moon“
  • Saturn’s Moons section
  • Enceladus Information
  • Titan Information
• Poetry Archive - “When I Heard the Learn’d Astronomer“

New Horizons was successfully launched today from Kennedy Space Center in Florida, USA after previous delays due to high winds and power outages. A slight delay today because of high clouds preceded a picture perfect launch.

At the moment New Horizons is rocketing away from the Earth and will pass the orbit of the moon in just 9 hours, the fastest yet for a space craft. The speed is necessary to get the spacecraft to Pluto in a reasonable amount of time, just under 10 years. In three months, New Horizons will pass the orbit of Mars, and then in a year it will fly by Jupiter and pick up the extra speed it needs to explore the Kuiper Belt region of our solar system. New Horizons will fly by Pluto and its moons in an event that will last just 24 hours in July 2015, snapping images and gathering other data that could revolutionize our understanding of the solar system and planet formation. After Pluto, New Horizons will be targeted toward other Kuiper Belt objects for exploration.

More Information

• New Horizons – NASA’s Pluto-Kuiper Belt Mission
• Images from Kennedy Space Center

Update: Launch postponed to Wednesday, January 18, 2006 due to high winds.

New Horizons and the Atlas rocket on which it sits were rolled out to their launch pad at Kennedy Space Center in Florida, USA yesterday. Only hours remain before the launch window opens up and NASA attempts to launch the piano-sized spacecraft on its mission to explore Pluto and the Kuiper Belt. NASA TV will provide live coverage and a live cam of the launch pad is available on the New Horizons launch site.

More Information

• New Horizons – NASA’s Pluto-Kuiper Belt Mission
• Images from Kennedy Space Center

(Disclosure: Richard Leis is an operations team member located at the University of Arizona for NASA’s Mars Reconnaissance Orbiter (MRO) High Resolution Imaging Science Experiment (HiRISE.))

Although the Mars Reconnaissance Orbiter (MRO) and its High Resolution Imaging Science Experiment (HiRISE) are less than two months away, spacecraft already in orbit around Mars continue to send back breathtaking images of the surface. Case in point is the image to the left taken by Mars Global Surveyor’s (MGS) Mars Orbiter Camera (MOC) of outcrops in Becquerel Crater. These outcrops are believed to be sedimentary layers and perhaps evidence for a lake in the crater in the distant past. Sediments carried into the lake by water channels settled out over time to create distinct layers. The number of discrete layers present in this image suggest that surface water played a role in shaping the martian surface for a significant period of time. While today Mars is a frigid desert, it may have been a much more hospitable and wet planet in its early history.

HiRISE will up the ante in scientific discovery on Mars by providing unprecedented resolution from orbit. The HiRISE science team will continue, among other priorities, to observe surface layering as evidence for water processes on ancient Mars. The orbital efforts of NASA’s MRO, MGS, and Mars Odyssey, ESA’s Mars Express, and periodic rover missions on the ground, represent the most exhaustive exploration of another planetary body.

MOC pictures of the day can be found on the Malin Space Science Systems (MSSS) website. MSSS also provided the Mars Color Imager (MARCI) and Context Imager (CTX) on board MRO. If all of these acronyms are giving you a headache, you are not alone: science team members experience the same symptoms. The list on the right under “More Information” provides full names for select spacecraft and instruments, their acronyms, and links to team websites.

More Information

• Malin Space Science Systems (MSSS) Picture of the Day
• Mars Global Surveyor (MGS)
  • Mars Orbiter Camera (MOC)
• Mars Reconnaissance Orbiter (MRO)
  • High Resolution Imagine Science Experiment (HiRISE)
• Mars Odyssey
• Mars Express
• Mars Exploration Rovers (MER)
• Mars Science Laboratory (MSL)