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Using over 6 years of magnetic field data (October 2014–December 2020) collected by the Mars Atmosphere and Volatile EvolutioN, we conduct a statistical study on the three‐dimensional average magnetic field structure around Mars. We find that this magnetic field structure conforms to the pattern typical of an induced magnetosphere, that is, the interplanetary magnetic field (IMF) which is carried by the solar wind and which drapes, piles up, slips around the planet, and eventually forms a tail in the wake. The draped field lines from both hemispheres along the direction of the solar wind electric field (E) are directed toward the nightside magnetic equatorial plane, indicating that they are “sinking” toward the wake. These “sinking” field lines from the +E‐hemisphere (E pointing away from the plane) are more flared and dominant in the tail, while the field lines from the –E‐hemisphere (E pointing toward) are more stretched and “pinched” toward the plasma sheet. Such highly “pinched” field lines even form a loop over the pole of the –E‐hemisphere. The tail current sheet also shows an E‐asymmetry: the sheet is thicker with a stronger tailward trueJ→×trueB→ $\overrightarrow{J}\times \overrightarrow{B}$ force at +E‐flank, but much thinner and with a weaker trueJ→×trueB→ $\overrightarrow{J}\times \overrightarrow{B}$ (even turns sunward) at –E‐flank. Additionally, we find that IMF Bx can induce a kink‐like field structure at the boundary layer; the field strength is globally enhanced and the field lines flare less during high dynamic pressure.

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The flapping motion of Mercury's magnetotail current sheet is investigated based on the observations of MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER). The typical flapping period in Mercury's magnetotail is much shorter (~13 s), comparing with ~10–20 min at Earth's magnetotail. The magnetic field oscillation amplitude induced by flapping motion is larger near both flanks than that around tail center. Similar to Earth's magnetotail, there are two flapping types existent in Mercury's magnetotail, one is the kink‐like flapping that can propagate as traveling waves, and the other one is the steady flapping that does not propagate. Both flapping types distribute widely in magnetotail. The kink‐like flapping waves propagating either dawnward or duskward can be observed across the entire magnetotail current sheet, which suggests that the energy sources for triggering the kink‐like flapping waves should locate around both tail flanks instead of tail center as is for the Earth's magnetotail.

A macrocyclic polyurea oligomer was synthesized from a sustainable CO2 route. MALDI-TOF and tandem mass spectrometry were used to confirm the formation of macrocyclic polyurea oligomers via fragment analysis.

Quantitatively estimating magnetotail flapping motion is critical for understanding and characterizing its dynamical behaviors. Such estimation can be achieved in principle by the multipoint analysis of spacecraft tetrahedron, for example, Cluster or MMS mission, but, owing to the inability of single‐point measurement to separate the spatial‐temporal variation of magnetic field, would be inadequate for a single spacecraft. Since single‐point missions dominate explorations of planetary magnetotail, we have developed a single‐point method based on the magnetic field measurement that quantitatively estimates the parameters of flapping motion, including spatial amplitude, wavelength, and propagation velocity. By comparing several applied cases with the multipoint analysis of Cluster, we demonstrate that our method can be reasonably applied to infer the average parameters over the whole flapping period when magnetotail is during quiet phase (magnetic field in magnetotail does not experience significant temporal variation). Thus, this method could be applied widely to the “big data set” accumulated by single‐point spacecraft missions in order to study magnetotail flapping dynamics.

As it approaches Mars, the solar wind flow, which carries a "frozen-in" interplanetary magnetic field (IMF), will be decelerated and deflected upon interaction with the Martian ionosphere, resulting in an induced magnetosphere (e.g.

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