Where is the Mars Scout now

The Pathfinder & Sojourner logbook


Pathfinder declared dead
The official "time of death" for the Mars Pathfinder was set to March 10, 1998 at 10:21 p.m. CET. Before that, the last attempt was made to contact the probe. On March 10th at 7:53 p.m., DSN station 15 in California issued the command that the probe should switch on the main antenna. Due to the distance between Mars and Earth, the signal took 19.8 minutes to get there. Accordingly, a response was expected at 8:33 p.m. CET, but the Pathfinder did not respond. The signal was sent for another 50 minutes until 9:25 p.m. After another 40 minutes of waiting no answer could be received and so the contact attempt by the Deep Space Network ended unsuccessfully at 0:30 a.m. CET.


Last contact attempt
Today the NASA researchers will try to connect to the Pathfinder for the last time. From 7:30 p.m. CET, the antennas of the deep space network will be directed again at the Pathfinder. However, it would be a sensation if the contact attempt should work, because no connection could be established since the end of September last year.


Pathfinder mission officially completed
Today NASA ended the Pathfinder project.


Pathfinder mission will finally end next week
Since the connection could not be established properly since September 27th, the mission will officially be completed on November 4th - exactly 4 months after landing on Mars. NASA named the mission the most successful interplanetary project. Brian Muirhead said he was "sad not being able to properly say goodbye to a good friend."

The mission was the successful start of the Discovery project, in which NASA would like to seek more scientific knowledge about our cosmic environment with cheaper probes.


Still no contact with the Pathfinder
Since October 7th, 1997 no signal could be picked up by the Pathfinder. The NASA researchers are trying to establish a connection, as far as the Deep Space Network is available, but the probe has not yet responded. It is assumed that the probe is still working, but the sending and receiving systems are disturbed by the cold.


Again problems with the radio connection
The NASA technicians were able to do so on October 7th. Received a signal from the Pathfinder again after 1½ weeks, but the probe has been silent again since then. On October 7th, the Deep Space Network Station in Spain was able to receive a 15-minute signal, from which it emerged that the Lander and Sojourner work in NO-BAT mode, i.e. have to get by without batteries. The probes start automatically when the solar radiation is high enough to supply the probes with energy.

However, no successes have been reported since this signal. One problem could be the lower temperature of the probe. In the past, you could warm up the station's antennas because the systems were switched on for several hours. Since the transmitter systems could not be warmed up for almost three weeks, this could impair some of the properties of the probe. As soon as a connection to the Pathfinder can be established, the clock will be reset and the probe will be prompted with new commands to transmit all technical data to earth the next day.


Sojourner on a long journey
After 83 days of various examinations, the Pathfinder mission is now entering a new phase. In this phase, the rover will make its longest journey to date and will primarily carry out technical investigations. The Pathfinder is now finally a pathfinder and trailblazer for subsequent missions. Accordingly, Brian Muirhaid, the Pathfinder Project Manager, said: "We have convinced ourselves that we know how to build robots that operate in the inhospitable environment of Mars."

The rover has initially carried out its last APXS measurement and after the data has been transferred it will embark on a 50 m drive around the lander. The rover carried out this last measurement on the Chimp rock, which is located behind the so-called Rock Garden. Sojourner has been on the road ten times as long as the original, seven-day primary mission. So while she continues her journey, the lander will continue to record the Martian environment in order to complete the "Super Panorama". This panorama is obtained from over 1 gigabit of data, 80% of which have already been transmitted to earth. However, this will not be finished until the end of October, as the data transmission times of the Deep Space Network are still limited.


Pathfinder still in good shape
Yesterday's data transfer was successful and showed that both the station and Sojourner are still fully functional and continue their mission. The computer problem caused by the wrong command sequence should be resolved with the next data transfer. The evaluation of the data continues, but sensational new findings will probably only be available again on September 11th. come when the Global Surveyor reaches the red planet and will map the surface.


Weather forecast from Mars ever more accurate: Almost like smog in Los Angeles
Sunset with halo
The daily weather forecast for the red planet could be further refined in the course of the mission and the future task of the Pathfinder will be primarily to monitor the atmosphere. According to Matt Golombeck, this mission could continue for another year. But important insights have already been gained: blue ice clouds darken the sun in the morning and would create about the same view for a Martian as strong smog in large cities on earth. Nevertheless, the water vapor concentration in the Martian atmosphere is only very low: The water would only form a layer on the Martian surface that is only a quarter of the thickness of a hair! For the next few days Tim Schofield predicts very warm weather of -8 ° C, with a rain probability of exactly 0%.
Sunset with halo


Reasons for computer crashes could be found.
The reasons for the repeated computer crashes have probably been found again. This time it appears to have been a sequence of commands from Earth. Rearranging the order of these commands could solve the problem, according to NASA researchers; the first tests were then also successful. Since the power supply of the probe is switched off at night to save energy, a missed data transfer always means the loss of some data. Due to the poor availability of the Deep Space Network, operations were restricted several times in the last week, as otherwise the data would have been lost anyway.


No data transmission planned for today (Sol 46)
Since the Deep Space Network is not available, no data transfer takes place today.


Another interruption of the data transfer on Saturday could be made up, but Sojourner got stuck
The collapsed data transfer on Saturday could be made up for on Sunday after a small correction. In just over an hour, 26 MB of data could be transmitted to Earth. Meanwhile, the rover got stuck between two stones as it passed through. The stones form a kind of passage to the southwest part of the Rock Garden.


Way continued again
After there was an antenna problem with the little rover on Thursday, it can now continue on its way to Shark. At the same time, the rover's autonomy is to be further increased so that it can better circumnavigate obstacles. Unfortunately he got problems with two stones during the changeover, but it is expected that he will be "on tour" again.


Awakened with music ...
As every morning on Mars, Pathfinder and Sojourner were woken up again yesterday with a piece of music. The NASA scientists have actually been sending a different musical wake-up call into space every morning since the start of the mission to wake the Sagan Memorial Station and Sojourner from their nocturnal hibernation (original quote from JPL). A current list of the pieces of music is available from JPL. The friendly treatment of the two earthly emissaries on the red planet seems to be worthwhile: Both thank you with great reliability.
Sojourner reached the Hassock rock yesterday after minor problems with some stones in the way. On the way she (!) Took this best photo of the Sagan Memorial Station so far from the Rock Garden.


Sojourner's way across Mars
During the first 38 days of the mission, Sojourner was able to explore the area around the landing site in detail; the JPL has drawn his way around the Sagan Memorial Station on the following panorama picture. At the same time, the names of all the striking stones and rock formations in the area are marked on it: The landing site is now as familiar to the scientists as the back of their hand.

The rest of the program is now routine, Sojourner and Sagan Memorial Station work from sunrise to sunset, with the onset of dusk, work to conserve the batteries is stopped.


Pathfinder and Sojourner break all records
The Pathfinder mission beats all records on Mars and Earth: In the first 30 days, 556 million hits were counted on the JPL's WWW pages. Pathfinder has become the biggest internet event of all time.

But the mission itself is more successful than ever thought: the scientists are extremely confident about the quality of the batteries and it is now hoped to extend the project over several months, if not even over a year. You could use it to explore the different seasons on Mars, at the moment it's late summer in the landing area! The first sandstorms are expected there in November and December and Pathfinder will have to pass its next test.

The meteorological investigations have already produced astonishing results: For example, four "dust-devils" could be observed, these are small mini-tornadoes similar to those in the earth's atmosphere.


Sojourner is about to climb hills
Now turn towards the hills, said Matthew Golombek, explaining that one possible goal of the rover in the near future might be to climb the hills. Sojourner would have to overcome about 18 meters in altitude. It sounds like a short drive, but it is a big challenge for the rover. Sojourner would have to cover about 90m on his way, which is quite a lot when you consider that he has only driven a full 52m so far. Since the rover only drives a few meters per hour and stops constantly to check whether there is still a connection to the lander, the journey should take well over a month. But before Sojourner goes on a climbing tour, she will examine some stones in the "Rock Garden" for the next month.
By the way: In contrast to the German usage, Sojourner is female among the Americans! But: how should you do this in German? Because a rover can hardly be female ..... so in the future Sojourner, THE rover ???, Certainly not!


Sojourner starts moving again after it has been automatically switched off
Pictures of the rover, which the lander has now taken, show that the automatic interruption of the journey was only caused by a small stone. Sojourner had switched himself off on his 10m long walk from the Mermaid Dune to the Rock Garden because a small stone was in his way. Probably his sense of balance switched him off. If the rover had hit the stone with a wheel, it could have overturned. However, since his righting mechanism no longer works, the mission would then be over. In order to save the batteries, the lander was also given the order to switch off the little rover after sunset.


Sojourner awakes from sleep
As planned, the lander's clock woke the station and the rover. According to Carl Steiner, the easy recharging of the batteries worked perfectly. The researchers sent commands to the rover to investigate further and to make a few turns to throw dust off the solar cells. JPL spokeswoman Diane Ainsworth said the mission would continue until the wheels break off the rover. The next destination will be the Rock Garden. The batteries of the Sagan Memorial Station could be recharged to almost half of the original level, a higher charge is not possible with the type of batteries used. The Sojourner was also allowed to go on vacation, although he only has batteries that are not rechargeable, since the lander is used for data transmission.


Pathfinder is taking a short vacation
The Pathfinder was given a day of rest today because the scientists want to conserve the batteries. You also want to buy some time to fix a bug that occurred two days ago. Although the researchers tried to explain some things, the error remained an unanswered question until the end of the working day. It is now assumed that an incorrectly adjusted instrument caused the error. During the night the rover stood near a dune called the Mermaid.


Sojourner hyperactive ....
After Sojourner has already been on longer trips in the last two days, his task for the next few days is also "driving, driving, driving". This also corresponds to the original planning at the beginning of the mission, because gradually both the batteries of the Sagan Memorial Station and the Sojourner are draining. In any case, Sojourner has already had far more than the planned seven (!) Days of his planned duration of deployment behind him and the "extended mission" is now also coming to an end. So you use the bright time of day to make further expeditions and experiments with the electricity from the solar cells.

After Sojourner has circled the Mini-Matterhorn stone, there is now a photo of this stone with the lander in the background. The shadows in the foreground come from the Sojourner's antenna and solar panels.

The daytime temperatures recently are like at the beginning of the mission and very typical for this time of year on Mars: -79 ° to -12 °, almost bearable for humans too. On the way back from the Mini-Matterhorn, Sojourner stuck his APX again in the Martian soil ... and then got stuck again for a short time. In the meantime, however, one is so confident in the control that briefly engaging reverse gear could remove the disturbing stone from the wheel profile.


Sojourner was aiming too high
At sunrise at Sol 23 it became clear why no data had been received from Souffle rock: Sojourner wanted to go a little too high and climbed a bit on the rock. As a result, his spectrometer did not come into contact with the rock. The automatic navigation worked, but on the last 25 cm you had been a bit too fast again manually.
The rest of Sol 23 went completely flawless. Sojourner began his global exploration of the rock garden, as the area around the Sagan Memorial Station is called, passed the rocks of Casper, Desert Princess and Bakers Bench. Overall, this meant automatic navigation over more than 6 meters: the longest distance that Sojourner had ever covered autonomously. In the future, Sojourner will drive to the Mini-Matterhorn and take more photos there.


Sojourner has grown up ... and can now drive alone!
The microrover was able to cover a three-meter-long route to the rock "Souffle" on its own at the weekend. This was made possible by the command "find rock", with which Sojourner is instructed to search for a rock in its vicinity and to head for it. He stopped correctly about 25 centimeters before the found rock, which he is now to examine. Sojourner navigated with his laser system with which he can recognize obstacles. The control from the earth consisted only in the specification of two waypoints, Sojourner managed the rest on his own. Up until now, the rover was always given a series of waypoints that it had to recognize and approach one after the other in order to find its way across Mars.


Sojourner is fed up (dirt)
NASA researchers are still waiting for the results of the latest action by Pathfinder's rover: Sojourner stuck the night through his nose into the Martian soil. On the one hand, the chemical investigation of the Martian soil is to be continued and, on the other hand, the mechanical investigation is to begin. Then Sojourner is supposed to drive to a rock called "Lamb".

Mars rocks highly magnetic
The Martian rocks studied are highly magnetic. There is only one place on earth where rocks with similar magnetism can be found. Nevertheless, scientists believe that Mars would be a wonderful playground for children. Mars would be very suitable as a sandpit for children. Due to the lower gravity, the children could jump high and make small sandstorms. However, the parents would hardly like this, according to Pete Smith, who is responsible for the photographic recordings, because the Martian dust would settle everywhere in the clothes.


Press conference at JPL
18 days after landing on Mars, the Pathfinder has achieved all of its primary scientific goals and continues to function with virtually no errors. All problems that have arisen in the course of time have been resolved so far, some of them were even only "earthly in origin". This is the brief summary of the course of the mission so far.

In the last week, Pathfinder sent more than 300 MB of data, which must now be evaluated, as reported by Matthew Golombek.The communication problems in the meantime could be solved. The rover, meanwhile, continues what Golombek called aggressive maneuvers to inspect rocks and sand. Special attention is now being paid to the Martian soil, as the tracks left by the rover suggested very fine sand. In fact, the Mars dust seems to be finer than talc powder, the particles are no more than about 50 micrometers in size. However, there is also an - as expected - small problem: The Pathfinder devices are slowly being covered with this fine dust from the Martian atmosphere, which, for example, will gradually reduce the effectiveness of the solar cells.


The source of the error in the data transfer was not the Pathfinder
The trigger for the poor radio connection to the Mars probe over the weekend was not a fault on the part of Pathfinder. Matthew Golombek stated that the error must be related to operations by the Deep Space Network. The causes of the problem should be eliminated in the next few days when one has returned to a more normal state. The connection could be re-established yesterday. Sojourner's next targets after the survey hits Earth are Half Dome, Witch, Shark and Flat Top.

07/21/1997 Ver 2.0

Radio connection restored!
The radio connection to Pathfinder was on July 21. at 2:45 am PDT (= 11.45 O'clock CEST) to be rebuilt. Although the cause of this error has not yet been found, work with Pathfinder has been resumed. The disturbed radio connection is the second unwanted break for the probe after a computer problem last weekend. Even if it is not yet clear whether this mishap will set the mission back, Matthew Golombek noted that the Sojourner has already sent more data to Earth than was originally planned. So the mission is still a complete success and the re-establishment of the connection gives hope that it can continue to be so. The data on the probe, which Pathfinder sent on orders from Earth, also showed that the lander and its little rover are in the best of "health"!


Radio connection disturbed
The connection to the Patfinder has been disrupted since Sunday evening. The working day of the NASA scientists ended unsuccessfully and so far the researchers still have too little information to be able to say what could have caused the error. However, with the repeated resets of the computer over the past week, this issue does not appear to be related, said Flight System Manager Brian Muirhead. However, he suspects that the bad connection is caused by a bad coordination of the Deep Space Network with the probe. The Deep Space Network is an amalgamation of NASA radio telescopes around the world that are used to transmit data to NASA's individual interplanetary probes. Probably the most successful unmanned mission, the two Voyager probes were controlled via the Deep Space Network.

Planned: Second attempt for Scooby Doo and recordings of Phobos
Sojourner is supposed to spend today trying to find a new place to study the rock.


Investigation of "Scooby Doo" failed to begin
It appears that Scooby Doo has not yet been investigated. NASA researchers suspect that the rover turned from its position when it was supposed to use its wheels to remove dust from the white rock. After he had needed about two days for the six meters from his previous examination subject Yogi, nothing seemed to stand in the way of the examination of Scooby Doo and it was hoped to be able to conclude the examinations in Sol 15. The scientists will now try again to place Sojourner in front of the rock.

Software error apparently found, new software should be installed
The bug in Pathfinder software that caused the repeated resets could be found. The trigger was a task that could not be ended because it did not have enough time to execute and it was therefore aborted in between. This problem can be solved by assigning a higher priority to the process and thus making more computing time available to it by the computer. The assigned priorities tell the operating system how much of the computing time is allocated to the task. The problem could be determined with test runs and should be solved with a modified software.

Obtained a high resolution image of the twin peaks
Pathfinder sent a very high resolution image of the twin peaks of interest to geologists. The picture is a stereo recording of the IMP and should help to uncover the origin of the rocks. The twin peaks could have been caused by meteorite impacts, but are too far away for Sojourner with a distance of about 0.86 or 1 km.

NASA uses "virtual binoculars" to display images
In order to be able to visualize the results better and more naturally, researchers at the Jet Propulsion Laboratory in Pasadena used "virtual binoculars" from n-Vision. Daryl Rasmussen of NASA's Intelligent Mechanisms Group explains that this technology gives a feeling of actually standing on Mars, as the observer can look at his surroundings like with real binoculars.



RESET problem still not solved!
The difficulties with unexpected resets of the Pathfinder on-board computer could obviously still not be resolved. Another data transfer was interrupted yesterday, so a 360 ° panorama could only be transferred incompletely. The last consistently successful downlink session was therefore almost 2 days ago.

The soujourner is still in standby mode in front of the rock Yogi.


More dust in the atmosphere than expected!
Sun observation on Mars!
The observations with the IMP camera show that there is significantly more dust in the Martian atmosphere than previously assumed. At a height of almost 13º the sun can no longer be observed. However, these results, which were obtained from solar observations with the IMP camera at different wavelengths, coincide with the data from the Viking probes. In the near future, the sky is to be searched for water vapor, i.e. for clouds over the landing site.

Frequent Computer Resets - Technical Problems
Mission control at JPL has not yet succeeded in locating the exact reason for the repeated resets of the computers on board the Pathfinder and the Sojourner. However, the cause is suspected to be faulty communication between Lander and Sojourner, which is why various changes have been made to the software. This should prevent further resets. The rover is currently on break, it has been in standby mode since Sol 10 (the tenth day on Mars).

Martian moon Deimos observed
On its third night on Mars after landing, Pathfinder made its first astronomical observation: In a photo published by JPL yesterday, the Martian moon Deimos, which is just under 12 km in size, can be seen. Unfortunately, his image only makes up two pixels in the IMP camera, because the IMP is not designed for astronomical observations.


First results from "Barnacle Bill"
The spectral analysis of the APXS shows that the rock is largely homogeneous in its composition and mainly consists of two different materials: soil-like components and dark rock. The spectra must now be compared with spectra made from the rocks on our planet.

Other problems with the data transfer solved
After the probe's computers had reset and therefore data transmission could not take place, the NASA technicians re-established the connection to the lander. On Friday the commands were sent to move Sojourner away from Yogi. The rover rammed the rock on Tuesday, but was not damaged because it shut down immediately. On Friday evening at 6:47 pm PDT (= Saturday, 3:47 am CEST) the mission control received Pathfinder's signal that he had received the commands from Friday. After that, data transmission was expected via the stronger antenna, but no signal could be received. A command was therefore sent immediately via the low-gain antenna that instructed Pathfinder to report back. Fortunately, this signal could be picked up and images and data were transmitted to earth.


Commands could not be sent
Due to a breakdown last night, no connection to the command transmission was established. The mission is not endangered by this, it will only delay the Sojourner and Pathfinder experiments. The Pathfinder receiving antennas are only active for a short time in order to save energy. Since the receiving system was programmed incorrectly by eleven minutes, it was not possible to send the commands to the probe afterwards. Yesterday evening at 8 p.m. PDT (= this morning, 5 a.m. CEST), the signals therefore had to be sent again.

NASA receives top-class support
US President Bill Clinton is also fascinated by the Mars images. He even wants to land on Mars one day!
In doing so, he is backing NASA's plans to land on the red planet in the foreseeable future. NASA could use the support, because after all, the US taxpayer has to pay for the missions.

Sojourner's accident has no consequences: investigation of "Yogi" still successful
A few days ago, the Microrover Sojourner collided with the rock "Yogi" that he was supposed to investigate. However, the accident did not cause any damage to the rover and it was able to successfully complete the investigation of the rock on the second attempt. Mission Manager Richard Cook said Jack Morrison's license was in no danger. Morrison and three other scientists take turns controlling Sohourner. When he tried to press his Alpha Proton X-ray Spectrometer (APX) against Yogi, he moved faster than planned. The rover automatically shut down immediately. According to Richard Cook, the accident was not unexpected and occurred during tests on earth. However, all devices are working properly again.


Pathfinder creates chaos!
NASA already put Pathfinder on their main page (http://nasa.gov) and some of the mirror sites and the JPL's special Pathfinder page were temporarily or still no longer available: Pathfinder stress in the data network is greater than ever expected!


Rock investigations hold surprises
The rock examinations of the "Alpha-Proton X-Ray Spectrometer" (APXS) of the Sojourner showed that "Barnacle Bill" is more like the rock formations of the earth than those of the Earth's moon. The rock must have been melted down several times because it contains a large amount of quartz.

Identified new destinations for Sojourner
In order to get the most comprehensive insight possible into the rock formations of Mars, "Yogi" should now be examined after "Barnacle Bill". One expects different results than those of the first investigation, since "Yogi" has a completely different appearance than "Barnacle Bill". The strange names for the individual rocks come from cartoon characters. In the opinion of Matthew Golombek from the Jet Propulsion Laboratory, the investigations will turn out very differently because, like on Earth, he expects a wide variety of rock types. But the investigation of cartoon characters continues: the next targets are "Casper" and "Scoobie Doo"!


"monster panorama" now also included in color

The big "monster panorama" that the IMP was able to capture.
In the foreground the ramp and the Sojourner. On the right side the airbags that should slow down the Pathfinder.


More Achievements
Quote from David Dubov (JPL / NASA): »What another excellent day. I know you all must be getting tired of hearing that, but we are still exhilirated. The entire Jet Propulsion Laboratory is floating about 3 feet off the ground ...«

First weather report from Mars
Temperature measurements of the ASI / MET at different heights above the Martian soil (1m, 0.5m, 0.25m) compared to the temperature curve of Viking
The first weather forecast could be created. All investigations of the ASI / MET experiment to investigate the atmosphere and the Martian weather have so far been carried out very successfully.


Rover could be extended
Finally on Mars!

After initial problems, the microrover "Sojourner" was finally able to descend the ramp and put the first bike on the Martian soil. The station's IMP camera provided impressive images of the procedure.

"monster panorama" recorded by IMP
The IMP camera was able to record a mars panorama that shows the whole area around the Pathfinder. Both lenses of the camera were used so that a 3D image can be generated from the recordings, which should help plan the route for the Sojourner.

Transmission rate could be increased
The transmission rate of the data to earth could be 8kb / sec. which is very good at the beginning of a mission. This means that more images can now also be sent to earth.