View Full Version : Just 19 not so simple steps.
PantyFanatic
01-03-2004, 09:51 PM
For the other Pixies that peek up........... NO! not skirts;) .... into the sky, and has interests in what is happening NOW.:)
Here are a couple links interest, information and monitoring sources.
The next few hours will be meaningful and exciting for some and important to everyone.
http://marsrovers.nasa.gov/mission/tl_entry1.html
http://www.nasa.gov/multimedia/nasatv/MM_NTV_Breaking.html
About now, the mission team will be preparing the spacecraft for communications during entry, descent, and landing. Spirit's cruise stage switches from its medium-gain antenna (which requires pointing toward Earth), to its low-gain antenna, which does not need to be pointed as precisely for the Deep Space Network antennas to pick up the signal. This switch slows the rate of data transmission, but is necessary to allow communications to continue when the spacecraft changes its orientation to point its heat shield forward.
There will be six REAL exciting minutes that I’ll let you know about. ;) LOL:D
PashkinThePanther
01-03-2004, 10:04 PM
I've been keeping track of this in my capacity as the local astronomy society president. Just means I shall have to say something about it at the next meeting as well.
See what weird things you find out about people...
PantyFanatic
01-03-2004, 10:11 PM
Should be an interesting morning for you too then.:)
PashkinThePanther
01-03-2004, 10:14 PM
And a long one! What with the Cowboys/Panthers game I am following and this mission as well, I shall have to spend rest of today asleep...? <yawn>
fenderchick
01-03-2004, 10:20 PM
I am open minded to any findings on Mars! To know if life existed at one time there.
PantyFanatic
01-03-2004, 10:22 PM
Step Two: Spacecraft Rotates
A few minutes after 7 pm PST, [03:00 GMT] the spacecraft carrying Spirit will rotate to face its heat shield forward for its final approach.
PashkinThePanther
01-03-2004, 10:24 PM
Originally posted by fenderchick
I am open minded to any findings on Mars! To know if life existed at one time there.
Apart from Pixies, i haven't seen a great deal of life on earth yet! :D
fenderchick
01-03-2004, 10:27 PM
LOL, understandable!!!
PantyFanatic
01-03-2004, 11:17 PM
Step Three: Transmission of Tones Begins
About 20:15 PST [04:15 GMT], Spirit will begin transmitting tones back to Earth that indicate the spacecraft's status. A low-gain antenna on the spacecraft's backshell begins transmitting simple "tones" (sustained radio frequencies coded to report the spacecraft's status). These tones give Spirit a way to keep communicating after the cruise stage is jettisoned. A dictionary of about 100 possible tones can provide information such as whether the cruise stage has separated, whether the parachute opens, and whether the deceleration rate is within the expected range.
From here on out, it’s gets very busy for the next half hour.;)
PantyFanatic
01-03-2004, 11:22 PM
Step Four: Cruise Stage Separates
As the tones begin, the cruise stage separation commences. This separation is the first stage the rover takes in shedding more than half of the spacecraft in which it has been warmly traveling during its 302.6 million mile journey through the frigid temperatures of space.
PantyFanatic
01-03-2004, 11:29 PM
Step Five: Spirit enters the martian atmosphere
"Six Minutes of Terror"
About 20:29PST [04:29GMT], one of the most challenging aspects of the mission begins. In only six minutes, the spacecraft will slow down from 12,000 to 0 miles per hour.
The lander should come streaking in through the martian atmosphere, going about 12,000 miles per hour. Given atmospheric friction, the outside surface of the heat shield will be as hot as the surface of the sun (1,447 degrees Celsius, or 2,637 degrees Fahrenheit), but the rover will be protected by the heat shield and will stay at about room temperature inside the lander. The heat shield also aerodynamically acts as the first "brake" for the spacecraft, slowing Spirit down by thousands of miles per hour.
This is the equivalent to us driving at a speed of 100 MHP and coming to a complete stop in 3 seconds, only it goes on for 6 minutes.:)
PantyFanatic
01-03-2004, 11:33 PM
Step Six: Parachute Deploys
About four minutes later, the spacecraft slows to about 1,000 miles per hour and is only 30,000 feet above the martian surface. At this point, a supersonic parachute is deployed. The parachute is based on the designs and experience of those used in the Viking and Pathfinder missions. The parachute for this mission is about 40% larger than Pathfinder's, and is made of two durable lightweight fabrics (polyester and nylon). <---- silky stuff makes everything work;)
PantyFanatic
01-03-2004, 11:34 PM
Step Seven: Heat Shield Jettisons
Twenty seconds after the chute deploys, the heat shield's work is complete, and it separates from the lander.
PantyFanatic
01-03-2004, 11:34 PM
Step Eight: Lander Separates
Ten seconds after the heat shield jettisons, the lander separates from the back shell and descends to the end of a "bridle", or tether. Spirit's altitude is about 20,000 feet at this point. The lander "rappels" down a Zylon tape on a centrifugal braking system built into one of the lander petals. The slow descent down the Zylon tape places the lander in position at the end of another bridle, which is made of a nearly 20-meter-long (65-foot-long) braided Zylon, an advanced fiber material similar to Kevlar. The Zylon bridle provides space for airbag deployment, distance from the solid rocket motor exhaust stream, and increased stability. The bridle incorporates an electrical harness that allows the firing of the solid rockets from the backshell, as well as provides data from the backshell inertial measurement unit (which measures rate and tilt of the spacecraft) to the flight computer in the rover.
PantyFanatic
01-03-2004, 11:35 PM
Step Nine: Radar Ground Acquisition Begins
Around 20:34PST [04:34GMT], when the lander is about 8,000 feet above the surface, radar systems on the lander determine its altitude and vertical velocity relative to the martian surface. These measurements will help the landing system decide how long to fire the retro rockets to bring the lander's verticle speed close to zero
PantyFanatic
01-03-2004, 11:38 PM
Step Ten: Descent imager takes pictures of the surface
While radar measurements are acquired, a descent imager will take three pictures of the surface and compare high-contrast features (for example, a crater) to determine the horizontal velocity at which the lander is moving across the surface. This measurement helps determine which transverse rockets should be fired in the retro rocket system.
PantyFanatic
01-03-2004, 11:42 PM
Step Eleven: Data transmission to the Mars Global Surveyor orbiter begins
The descent UHF (ultra-high frequency) antenna, mounted on the lander, begins transmitting once the lander descends from the backshell, which stays attached to the parachute. From the lander's position at the bottom of a tether (aka bridle) connected to the backshell, this antenna can transmit to the Mars Global Surveyor orbiter that will be passing overhead at this time. The link allows Spirit to supplement the tone-coded information with additional status reports that can be forwarded to Earth by Mars Global Surveyor almost immediately. The window for relaying information to Mars Global Surveyor closes by about 8:42 p.m., when the orbiter sets below the landing site's horizon, about seven minutes after Spirit hits the ground. Although this communication link has been extensively planned and simulated, there is no guarantee that Mars Global Surveyor will successfully relay information from Spirit. When the lander descends from the backshell, a low-gain X-band antenna mounted on the rover itself takes over from the backshell antenna the job of transmitting tones to Earth. It transmits tones until retro rockets fire, six seconds before impact. Then, during the spacecraft's impact, bouncing, and rolling, it transmits a carrier signal only.
PantyFanatic
01-03-2004, 11:43 PM
Step Twelve: Airbags inflate
Airbags inflate to protect the lander for a soft lading over the hard rocks on Mars. The airbags used in the Mars Exploration Rover mission are the same type that Mars Pathfinder used in 1997. Airbags must be strong enough to cushion the spacecraft if it lands on rocks or rough terrain and allow it to bounce across Mars' surface at freeway speeds after landing.
PantyFanatic
01-03-2004, 11:43 PM
Step Thirteen: Retro rockets fire
At this point in entry, descent, and landing, the lander is only a football-field length off the ground. Three rockets fire, bringing the airbag-cocooned lander to zero vertical velocity nearly 40 feet off the ground
PantyFanatic
01-03-2004, 11:44 PM
Step Fourteen: Bridle is cut and first impact occurs
At about the height of a four-story building and three seconds before landing, the bridle is cut and the vehicle freefalls to the surface. The mass of Spirit and its lander is about 544 kilograms (1,200 pounds).
PantyFanatic
01-03-2004, 11:45 PM
Step Fifteen: Lander rolls to complete stop
The rover, protected by its lander structure and airbags, could bounce up to four or five stories high and roll as far as 1 kilometer (0.6 miles) across the martian surface before it comes to a complete stop around 20:45 PST [04:45GMT].
PantyFanatic
01-03-2004, 11:52 PM
Step Sixteen: Communication attempt begins
About 14 minutes after Spirit hits the ground and four minutes after it stops bouncing and rolling, transmission of tones resumes from the rover's low-gain X-band antenna. If the rover lands with its base petal down, this antenna will be near the top of the bundle and in a position that may be favorable to sending a signal to Earth. Its transmission of tones ends 150 seconds later. The lander, however, may not be in this orientation. Therefore, beginning about three minutes later, another low-gain X-band antenna, this one mounted on the lander's base petal, transmits tones for 150 seconds as well.
PantyFanatic
01-03-2004, 11:54 PM
Step Seventeen: Critical deployments begin
Immediately after landing, the rover will go through a series of critical deployments for 80 minutes or longer, depending on which base petal it lands. The lander will retract its airbags, deploy its lander petals and solar arrays, and raise its panoramic camera mast.
PantyFanatic
01-04-2004, 12:04 AM
That's what is SUPPOSE to be happening.:) ......... on another planet................. FAR away from us. To me that's one hell of a statement and an even more impossible agenda. Each time I look at the specie, what it does to eah other, itself, the planet and shake my head ................ we do something like this to show we CAN do something worth while.
God HAS to be a woman!...... Will just ALWAYS make you wrong. :rolleyes:
PantyFanatic
01-04-2004, 01:16 AM
Step Eighteen: Data transmission to the Mars Odyssey orbiter begins
The Mars Odyssey orbiter passes across the sky above the landing site for about 15 minutes. If Spirit gets through its critical deployments in time, it will use the rover's UHF antenna to send information, perhaps including images, to Odyssey. Odyssey forwards that information to Earth between 23:00 and midnight PST. However, Spirit might not be ready to communicate with Odyssey by the time the orbiter flies overhead, especially if Spirit ends its roll with a side petal instead of its base petal down. Also, as with the communications attempt with Mars Global Surveyor (step eleven), there has never been a chance to test communications between a transmitter on the surface of Mars and an orbiter.
PantyFanatic
01-04-2004, 02:13 AM
Step Nineteen: Spirit sleeps
Under normal conditions, the rover goes to sleep after the Odyssey pass.
PantyFanatic
01-04-2004, 02:16 AM
It will be very interesting to see the degree of success is possible for such a giant task. Good luck to one of the more noble endeavors of a selfish specie.
dicksbro
01-04-2004, 05:08 AM
Thanks for the site references and the discussion of the steps Spirit will take. Very interesting stuff, isn't it?
PantyFanatic
01-04-2004, 05:37 AM
Jubilant Mars Exploration Rover Team members cheer at Jet Propulsion Laboratory as they get the first tones from a healthy Spirit on Mars! Check back to this page for more rover updatesJubilant Mars Exploration Rover Team members cheer at Jet Propulsion Laboratory as they get the first tones from a healthy Spirit on Mars! Check back to this page for more rover updates
:jump::line::jump:
PantyFanatic
01-04-2004, 05:41 AM
:D...............:D...............:D...............:D...............:D
NASA's Mars Exploration Spirit is sending back its first images from the surface of Mars. More images will be available shortly. NASA's Deep Space Network received a signal confirming that Mars Exploration Rover Spirit is alive after rolling to a stop on the surface of Mars(Updated - Jan 4. 12 am PST)
:D...............:D...............:D...............:D...............:D
PantyFanatic
01-04-2004, 05:43 AM
Good night.;)
Lilith
01-04-2004, 09:41 AM
YAY indeed! Very cool. Thanks for all the info PF!
LixyChick
01-04-2004, 12:20 PM
WOW! The next civilian in space PF? Would ya if ya could?
I was just wondering if those aliens that keep crapping up our equiptment just have hearing like a dog and all those tones are driving them crazy??? LMAO! JK hun..I have a warped sense of wonder!
BTW hun! TY for the information....it's extremely interesting and I know all the hard work you put into gathering it! *hugs*
Scarecrow
01-04-2004, 03:51 PM
Was watching Fox News live when the Spirit sent back the 150 second tone. Was a very exciting time.
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