1. SMILE is a joint Chinese Academy of Sciences (CAS) / ESA mission designed to study the chain of events from the solar wind, through the dayside, to the space weather consequences as viewed through the lens of the global aurora.
The SMILE team mission won a joint CAS/ESA competition (in 2015). The team is led by Grazziela Branduardi-Raymont of MSSL (UK) and Chi Wang of the National Space Science Center (China). The mission will carry four instruments (below), two from China, one from the UK, and one from Canada, with contributions to one instrument from Belgium.

2. SMILE – Solar wind Magnetosphere Ionosphere Link Explorer
Objective: Explore how solar wind magnetosphere interaction drives space weather.
Science Targets
What are the fundamental modes of the dayside solar wind/magnetosphere interaction?
What defines the substorm cycle?
How do CME-driven storms arise and what is their relationship to substorms.
Mission Plan in Brief
Single satellite in high altitude (18 Re) orbit.
Solar wind in situ: B-field and plasma (H+, He+, He++ 3D velocity distributions)
Imaging: Soft X-Ray (magnetopause/magnetsheath) and UVI (global aurora).
Self explanatory --- we want to measure B- and plasma in the solar wind just outside the bowshock, while looking simultaneously at the dayside magnetopause with a soft X-Ray Imager (SXI) and at the global northern hemispheric aurora with a UV imager working in LBH.

3. (University of Leicester - Steve Sembay PI)
SMILE – SXI
(University of Leicester - Steve Sembay PI)
I don’t really know how the soft X-Ray imager will work (we have our heads down building TREx and developing the concept for SMILE-UVI), but the idea is that soft X-Rays from the dayside magnetopause and sheath will allow one to track e.g. motion of the magnetopause. This is cutting edge, and will give us a new view of something we’ve only had glimpses of in the past.

4. UCalgary – Eric Donovan PI
SMILE – UVI
UCalgary – Eric Donovan PI
Centre Spatial de Liege and U de Liege – Benoit Huber Co-PI
National Space Science Center – Yongmei Wang Engineer

5. SMILE – UVI
Objectives
Among other requirements, we want to track, for example, the time series of open magnetic flux and how it changes in response to dayside dynamics.
To meet our objectives, we need to track the oval, its boundaries and brightness distribution (100 km resolution).
Complicating our objectives is at apogee we will be 3X as far from Earth as Image and Polar, and our mass budget is just 11 kg.
Courtesy Steve Milan

6. SMILE – UVI The Instrument
The requirement to, for example, identify the open-closed boundary at all local times requires a low brightness threshold and suppression of out of band photons (so the LBH aurora is most of the signal on the dayside) and stray light.
We’ve come up with an innovative new four-mirror on-axis design which will meet these objectives (see Unick et al., JGR, 2016).
Belgian colleagues at ULiege and CSL are carrying out a complete parallel design study, and will be responsible for the dielectric filters.

7. SMILE – UVI
Advantages
The nearly 20 Re apogee presents challenges, however it offers up to 40 hours of continuous viewing of the northern hemisphere aurora – longer by nearly a factor of 3 than any previous continuous time series of the global (hemispheric) aurora.
Further, the imager is designed to give 1 minute/100 km resolution at ~20 Re but will be imaging the not-full-globe for two 3 hour periods each orbit (between 5 and 10 Re geocentric) where we hope to achieve continent-scale km 15 second images – sort of THEMIS-ASI scale without clouds and trees.
The aurora over Ontario and Quebec seen
from the LEO Suomi satellite.
The first bullet means for example that we will have 40 hour time series of the OCB and therefore the open flux…. This time series has been elusive (we have images where the threshold is high enough that we aren’t confident that the OCB is not poleward of where the luminosity falls off. Also we have proxies that are local to regions but not global like the SuperDARN echoe spectral widths or the “redline shelf” on the nightside. So this will be an important thing for looking with observations at the quantitative tradeoff between dayside and nightside reconnection, and how it responds to dayside dynamics.
Courtesy NASA

8. SMILE
Status
Almost all of the funding for the instruments is secured or should be in the next few months.
The mission team is coming up to the conclusion of the ESA study phase (roughly phase A/B0).
Mission adoption is in February 2017.
Provided that the mission is adopted launch is expected in 2021 or 2022.