{"id":13489,"date":"2018-11-27T00:10:17","date_gmt":"2018-11-26T16:10:17","guid":{"rendered":"https:\/\/wp-productionenv-bjg9h2g2bgg5b8aa.southeastasia-01.azurewebsites.net\/news\/insight-tweaks-trajectory-to-home-in-on-mars-landing-site\/"},"modified":"2018-11-27T00:10:17","modified_gmt":"2018-11-26T16:10:17","slug":"insight-tweaks-trajectory-to-home-in-on-mars-landing-site","status":"publish","type":"post","link":"https:\/\/starpath.global\/news\/insight-tweaks-trajectory-to-home-in-on-mars-landing-site\/","title":{"rendered":"InSight tweaks trajectory to home in on Mars landing site"},"content":{"rendered":"
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Artist\u2019s concept of the InSight spacecraft in its interplanetary cruise configuration. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n

On the eve of its blazing entry into the Martian atmosphere, NASA\u2019s InSight spacecraft briefly pulsed its control jets Sunday to target a safe, flat landing zone near the planet\u2019s equator \u2014 the last in a series of trajectory correction maneuvers since the mission\u2019s launch in May.<\/p>\n

Still attached to its cruise stage, which ferried the lander from Earth to Mars, InSight fired its thrusters at 4:47 p.m. EST (1:47 p.m. PST; 2147 GMT) Sunday to steer the spacecraft closer to an ideal landing site in Elysium Planitia, a broad, flat equatorial plain selected by mission managers because of its relative safety.<\/p>\n

InSight\u2019s landing zone is free of large boulders, craters, and other topographic hazards, according to surveys based on high-resolution imagery from the Mars Reconnaissance Orbiter, a satellite in orbit around Mars.<\/p>\n

Officials ordered the trajectory correction maneuver in a meeting Sunday morning after an assessment of InSight\u2019s course toward Mars. The previous course correction Nov. 18 moved InSight\u2019s landing ellipse \u2014 a football-shaped area in which the spacecraft could conceivably touch down \u2014 to the mission\u2019s planned landing spot.<\/p>\n

But the ellipse did not have the landing target dead-center, and it included some areas with rougher terrain, where a landing might be more risky, according to Tom Hoffman, InSight\u2019s project manager at NASA\u2019s Jet Propulsion Laboratory in Pasadena, California.<\/p>\n

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Tom Hoffman, InSight\u2019s project manager, motions to a region officials hope the lander will avoid due to rougher terrain. Credit: NASA TV\/Spaceflight Now<\/figcaption><\/figure>\n

In a press conference Sunday, Hoffman said InSight\u2019s final course correction was expected to be \u201cjust a very small burn, it\u2019s only a few centimeters per second.\u201d<\/p>\n

\u201cIt\u2019s almost a breath of air out of your mouth,\u201d he said. \u201cWe hope that we\u2019re going to move about 11 miles (17 kilometers) from where we are today to that red X.\u201d<\/p>\n

Mission planners set aside propellant and time for InSight to conduct the trajectory correction maneuver Sunday, but officials were not sure it would be required until a meeting Sunday morning, according to Hoffman.<\/p>\n

\u201cIf we go farther northwest than where we\u2019re currently showing, we get into a region that we\u2019re not as comfortable landing in, which is the reason we had a very exciting \u2026 6 o\u2019clock meeting this morning,\u201d Hoffman said.<\/p>\n

\u201cWe listened to all the different inputs, and the final decision was to go ahead and do the TCM (trajectory correction maneuver), let\u2019s move ourselves back to that red X and be exactly where we really want to land, from both a safety standpoint, as well as making sure that we have the right location for our science instruments.\u201d<\/p>\n

Some InSight officials have joked that Elysium Planitia is the biggest parking lot on Mars, notable for its expanse and featureless terrain, not for the rugged geology often found at other Mars landing sites.<\/p>\n

\u201cWhere we\u2019re going to land is a place called Elysium Planitia, which very roughly translated means \u2018heavenly plain,\u201d Hoffman told reporters Monday. \u201cAnd, indeed, it is is a very heavenly plain, and it is very plain, but it is actually perfect. It\u2019s safe. It\u2019s great, not only to land, it\u2019s a great place to do the science that we want to do.\u201d<\/p>\n

A final opportunity to uplink commands to InSight is available to ground controllers around two hours before the spacecraft enters the Martian atmosphere at 2:47 p.m. EST (1947 GMT) Monday. Engineers may elect to send up minor adjustments to the algorithm that will guide InSight through the atmosphere to its landing site.<\/p>\n

The lander will jettison its cruise stage, which ferried InSight from Earth to Mars following the mission\u2019s May 5 launch aboard an Atlas 5 rocket, a few minutes before slamming into the outermost layers of the Martian atmosphere. The cruise module will burn up during its plunge toward Mars.<\/p>\n

InSight\u2019s heat shield will take the brunt of the force to slow InSight from its initial entry velocity of 12,300 mph (5.5 kilometers per second). Cocooned in a flying saucer-shaped shell, the lander will slow down using aerodynamic friction, building up temperatures on the outer skin of the craft\u2019s heat shield as high as 2,700 degrees Fahrenheit (1,500 degrees Celsius).<\/p>\n

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Artist\u2019s illustration of the InSight spacecraft descending under parachute. Credit: NASA\/JPL-Caltech<\/figcaption><\/figure>\n

A supersonic parachute will then unfurl \u2014 shot out of the top of the entry vehicle like a mortar shell \u2014 at a velocity of around 861 mph (385 meters per second), and at an altitude of approximately 36,400 feet (11,100 meters) above ground level.<\/p>\n

Fifteen seconds later, InSight will release its heat shield and extend its three landing legs, each fitted with a trigger sensor to detect touchdown.<\/p>\n

But InSight\u2019s parachute is not enough to slow the spacecraft enough for a soft landing. The Martian atmosphere \u2014 less than one percent the thickness of Earth\u2019s \u2014 is far too thin to allow landers to safely reach the surface using parachutes alone.<\/p>\n

InSight will next activate a landing radar to measure the spacecraft\u2019s altitude and descent rate, and after about two minutes under the parachute, the probe will release from its backshell at a speed of around 134 mph (60 meters per second) and an altitude of approximately 3,600 feet (1,100 meters).<\/p>\n

One second after backshell separation, the lander will begin firing 12 braking rockets to slow its descent velocity and null out horizontal movements. The spacecraft will also rotate to ensure it is in the correct orientation for touchdown, with its solar arrays extending east and west from the deck, and the robotic arm\u2019s work area on the south side of the lander.<\/p>\n

Around 164 feet (50 meters) above the surface, InSight will transition to a constant velocity mode. Around 15 seconds later, InSight will reach the surface at a velocity of around 5 mph (2.24 meters per second), and immediately switch off its liquid-fueled thrusters.<\/p>\n

Once on the surface, InSight will unfurl two fan-like solar arrays to begin generating power. Cameras on the stationary lander, built by Lockheed Martin, will survey its surroundings before engineers beam up commands for InSight to use its robotic arm to place a pair of science instruments on the nearby surface.<\/p>\n

One of the sensors is a French-built seismometer encased in a vacuum enclosure and a wind shield. It will detect tremors \u2014 marsquakes \u2014 caused by geologic activity deep inside the Martian crust.<\/p>\n

Another instrument, developed in Germany, will hammer up to 16 feet (5 meters) below the Martian surface and measure the heat coming from the planet\u2019s interior.<\/p>\n

The instrument deployments could take two or three months to complete as scientists and engineers on Earth methodically plan the sequence based on the conditions at InSight\u2019s unexplored landing site.<\/p>\n

\u201cIt\u2019s taken more than a decade to bring InSight from a concept to a spacecraft approaching Mars \u2014 and even longer since I was first inspired to try to undertake this kind of mission,\u201d said Bruce Banerdt of JPL, InSight\u2019s principal investigator. \u201cBut even after landing, we\u2019ll need to be patient for the science to begin.\u201d<\/p>\n

The lander will stand around three feet (90 centimeters) tall on the Martian surface, with some uncertainty because InSight\u2019s legs could compress into the soil after touchdown. With its solar panels unfolded, the lander will span around 19.7 feet (6 meters) wide.<\/p>\n

Data collected by InSight should reveal information about Mars\u2019s internal structure, including the size and make-up of its core. Scientists hope InSight\u2019s discoveries will tell them about how rocky planets like Mars and Earth formed.<\/p>\n

Mars has a geologic record dating back billions of years, a record that has been largely erased on Earth by plate tectonics and vigorous geologic activity that refreshes the crust.<\/p>\n

Email the author.<\/i><\/b><\/p>\n

Follow Stephen Clark on Twitter: @StephenClark1.<\/strong><\/em><\/p>\n","protected":false},"excerpt":{"rendered":"

Artist\u2019s concept of the InSight spacecraft in its interplanetary cruise configuration. Credit: NASA\/JPL-Caltech On the eve of its blazing entry into the Martian atmosphere, NASA\u2019s InSight spacecraft briefly pulsed its control jets Sunday to target a safe, flat landing zone near the planet\u2019s equator \u2014 the last in a series of trajectory correction maneuvers since […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"inline_featured_image":false,"footnotes":"","_links_to":"","_links_to_target":""},"categories":[2],"tags":[690,1913,1914,242,455,927,1183,472],"class_list":["post-13489","post","type-post","status-publish","format-standard","hentry","category-news","tag-cnes","tag-discovery-program","tag-dlr","tag-france","tag-germany","tag-insight","tag-jet-propulsion-laboratory","tag-lockheed-martin"],"acf":[],"_links":{"self":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/13489"}],"collection":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/comments?post=13489"}],"version-history":[{"count":0,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/posts\/13489\/revisions"}],"wp:attachment":[{"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/media?parent=13489"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/categories?post=13489"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/starpath.global\/blog\/wp-json\/wp\/v2\/tags?post=13489"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}