Welcome to SciTech's live blog of Curiosity's Mars landing event. Tonight jim in IA and myself (palantir) will double team a live blog leading up to an exciting event at about 12:31 Central time (+/- a minute or two) when we plan to celebrate the safe arrival of an incredible piece of technology on the planet Mars. Of course, you don't have to believe a couple of pie in the sky SciTech geeks like myself or Jim but no less that the Colbert Report has covered tonight's event in an interview with John Grunsfeld NASA's Associate Administrator for the Science Mission Directorate. I have no idea why that title reminds of Terry Gilliam's Brazil, but it does :)
Sending a mobile laboratory on a 350 million mile over 255 days through space is no easy task. But for Mars Science Laboratory that was the easy part, well maybe not :)
After that long trip the landing will be a white knuckle affair. As the say at JPL and NASA it will be seven minutes of terror.
So keep your fingers crossed because landing a spacecraft on Mars is successful in less than half the tries.
The Mars Science Laboratory (MSL) also known as Curiosity is a phenomenal instrument of human curiosity. We want to know, so we build machines to gather data against which we test our hypothesis. Curiosity is going to Mars to do just that, but putting it where it will provide the most useful information is critical.
Finally, here's a bit of Curiosity's backstory and NASA's plans for the mission...
We hope we'll see you over the imaginatively named divider-doodle :)
How did Curiosity get to Mars? The journey started back in November 2011 with the launch. Viewed from above the Sun and planets, they are moving counter-clockwise. The orbit diagram below shows how Curiosity needed to extend its orbit from the distance of Earth from the Sun to that of Mars. That required a speed boost to escape Earth orbit at about 25,000 mph relative to Earth. Once the craft achieved the proper speed and direction, it coasted on the long arcing path to intersect the orbit of Mars. Six mid-course corrections were scheduled marked TCM-1 thru TCM-6. TCM-5 was cancelled due to the accuracy of the trajectory. Click the image to make it bigger.
How Will It Get To The Surface? This diagram summarizes the important stages spoken of in the videos above. Click the image to make it bigger.
Gale Crater spans 96 miles (154 kilometers) in diameter, giving it an area about the equivalent of Connecticut and Rhode Island combined. It holds a mound, informally named Mount Sharp, rising about 3 miles (5 kilometers) above the crater floor, which is higher than Mt. Rainier rises above Seattle. The slopes of Mount Sharp are gentle enough for Curiosity to climb, though during the prime mission of one Martian year (98 weeks), the rover will probably not go beyond some particularly intriguing layers near the base. The actual landing site is to be within the small oval at the upper left in this image. This text and below are from the NASA Press Kit.
Gale sits at a low elevation relative to most of the surface of Mars, suggesting that if Mars ever had much flowing water, some of it would have pooled inside Gale. Observations from orbit that add evidence of a wet history include water-related clay and sulfate minerals in the lower layers of the mound, and textures higher on the mound where it appears that mineral-saturated groundwater filled fractures and deposited minerals.
Stratification in the mound suggests it is the surviving remnant of an extensive sequence of deposits that were laid down after the impact that excavated the crater more than 3 billion years ago. Each geological layer, called a stratum, is formed after the layer beneath it and before the one above it. The stack of layers that forms Mount Sharp offers a history book of sequential chapters recording environmental conditions when each stratum was deposited. This is the same principle of geology that makes the strata exposed in Arizona’s Grand Canyon a record of environmental history on Earth. For more than 150 years, geologists on Earth have used stacks of strata from globally dispersed locations to piece together a record of Earth history.
So what is the difference between the Mars Exploration Roves (Spirit and Opportunity) and the Mars Science Laboratory (Curiosity)? Curiosity weighs in at 1982 lbs (that's an Earth measurement) or 899 kilograms (that's an everywhere measurement) while Spirit and Opportunity are 374 lbs or 170 kilograms each.
Very pretty, but how about compared to a hooman bean? :)
Jim and I are manning the monitors, all systems are go. We are looking forward to your questions, comments, and insights. We will update the diary as the evening develops. Thanks for taking the time to witness an extraordinary event.
9:10 PM PT: Gee, I'd like the blue shirt concession at JPL/NASA :)
9:16 PM PT: Altitude coming up on 10,000 miles. Speed 9,256 mph
9:57 PM PT (jim in IA): Some applause in the control room as Curiosity is moving to another important stage in operations. The craft is transmitting entirely one way to Earth. Important commands are being executed to indicate a commit to the descent.
They are polling the various systems in the control room.
10:03 PM PT: about 12 minutes to cruise stage separation. That should raise some applause
10:03 PM PT (jim in IA): The lucky peanuts are being passed around. You can't take any chances.
10:08 PM PT (jim in IA): Odyssey has reported it did get repositioned. That means Curiosity data will be transmitted 'real time'.
10:08 PM PT: (palantir) coming up on 15 minutes to atmosphere on my telemetry :)
10:15 PM PT (jim in IA): Transmissions of carrier signal acquired. Tone signals are looking good. Cruise separation is confirmed.