The MAVEN team includes experts from many institutions and disciplines. The team blog is a forum for these individuals to share their personal experiences with the MAVEN community. From exploring the science of the mission, to the engineering behind the instrumentation, from the complex aspects of project management, to the access and use of data products, we hope you enjoy the opportunity to engage with the MAVEN team through these anecdotes.
MAVEN began its fifth “deep dip” campaign of the mission this week. Three maneuvers were successfully carried out to lower the periapsis (or lowest) altitude of the spacecraft by approximately 29 kilometers (18 miles), placing MAVEN into the targeted density corridor, where the average density of Mars’ atmosphere is 3.0 kg/km³. The fifth deep dip for MAVEN is uniquely located over the solar terminator (the boundary between dayside and nightside), close to the ecliptic plane, and at a Martian latitude of 35ºN.
The three maneuvers—carried out on June 7 & 8—required a total ∆V of 4.6 m/s and resulted in a periapsis altitude of ~119 km (74 miles). The purpose of the MAVEN deep dip campaigns is to sample a full range of altitudes within the upper atmosphere of Mars, providing complete coverage. At 119 km, MAVEN reaches the Martian homopause, which is the lower, well-mixed region of Mars’ upper atmosphere, where the density is about thirty times greater than at periapsis during a typical science orbit.(Read more»)
— MAVEN Principal Investigator Bruce Jakosky
As of today, MAVEN has been in orbit around Mars for one Earth year! And it’s been an action-packed year.
Some of the highlights include:
- Getting into orbit!
- Surviving the encounter with Comet Siding Spring
- Commissioning the spacecraft
- Carrying out ten months (so far) of observations during our primary mission
- Carrying out four deep-dip campaigns
The success of the mission so far is a direct result of the incredibly hard work of everybody who works (and has worked) on MAVEN. This one year at Mars reflects the tremendous efforts over the preceding dozen years. And the mission continues—we still have two months to go in our primary mission, and then we begin our extended mission. We’re obtaining an incredibly rich data set that is on track to answer the questions we originally posed for MAVEN and that will serve the community for a long time to come.
I hope everybody is as proud of what we’ve accomplished as I am! And here’s to the next year of exciting observations, analyses, and results!(Read more»)
MAVEN completes fourth deep-dip campaign
NASA’s MAVEN spacecraft, in orbit at Mars since Sept. 21, 2014, has completed the fourth deep-dip campaign of its primary science mission. The series of five-day campaigns are designed to lower the periapsis (lowest altitude) of the spacecraft above Mars in order to achieve a targeted atmospheric density corridor and to sample the lower, well-mixed portion of the Martian upper atmosphere. The density at 125 km (78 mi) can be 30 times that encountered during the nominal science orbits, where the periapsis is approximately 150 km (93 mi).
The latest deep-dip campaign began on Sept. 2nd with two “walk-in” maneuvers that lowered the periapsis of the spacecraft to 121 km (75 mi) above the Martian surface. These maneuvers had ∆V (delta-V or a change in velocity) magnitudes of 2.7 m/sec and 0.6 m/sec. The campaign concluded in the early hours of Sept. 10th with the second of two “walk-out” maneuvers, designed to raise the periapsis of MAVEN back to near 150 km. The maximum atmospheric density encountered during the deep-dip was 3.0 kg/km³.
The two “walk-out” maneuvers (executed on Sept. 9 & 10) had ∆V magnitudes of 3.3 m/sec and 0.6 m/sec, and raised the periapsis by 20 km (12 mi) and 4 km (2.5 mi) respectively. These maneuvers returned MAVEN to a nominal periapsis altitude of 145 km (90 mi) and achieved an estimated density of 0.11 kg/km³.(Read more»)
Bruce Jakosky, MAVEN principal investigator at CU-Boulder’s Laboratory for Atmospheric and Space Physics
MAVEN is about to carry out its first “deep-dip” campaign. This involves lowering the lowest altitude in the orbit from about 150 km above the surface to about 125 km. We do this so that we can measure the properties of that additional 25 km of the upper atmosphere between 150 and 125 km. It doesn’t seem like much, but this lets us go all the way down to the top of what we call the lower atmosphere, and it will let us make the connection then from the top of the upper atmosphere all the way down to the surface.
We’ll use three rocket-motor burns to lower the orbit, spread over three days. We do it gradually so that the spacecraft can “walk in” and we don’t get taken by surprise by anything along the way. Then we’ll stay in the “deep dip” orbit for five days, which covers about 20 orbits around the planet. Finally, we’ll use two maneuvers to “walk” back out and get back to our regular science mapping orbit.(Read more»)
David F. Mitchell, MAVEN Project Manager at NASA’s Goddard Space Flight Center
MAVEN is now fully into its Science Phase at Mars and the scientists have been releasing exciting results, not the least of which were recent findings from the Comet Siding Spring encounter. The Imaging Ultraviolet Spectrometer was able to observe intense emissions from magnesium and iron ions in the atmosphere in the aftermath of the comet encounter. The Neutral Gas and Ion Mass Spectrometer directly sampled and determined the composition of comet dust in Mars’ atmosphere, something that has never been done before. Our Solar Energetic Particle instrument observed significant solar activity both in the form of flares and coronal mass ejections from the Sun to Mars. We also generated a map of Mars’ ozone layer in the lower atmosphere. Finally, we’ve been able to provide a view of the escaping atmosphere of Mars showing the loss of atomic oxygen, atomic carbon, and atomic hydrogen.
Great science with much more to come!(Read more»)