One (significant) paper in the current Astrophysical Journal (Feb 10, Vol 980 #1):
Angrisani, M. Palomba, E. Longobardo, et al. Spectral Variations across Latitudes on Asteroid (3200) Phaethon art. 127 ada60d
If you aren’t already familiar with the object (3200) Phaethon, it’s ‘object’, neither truly asteroid nor comet (…or is it both?) First discovered as an asteroid (hence its designation, with an asteroid number), no coma or tail was visible. Then, the IRAS satellite was launched in the ‘80s. IRAS (InfraRed Astronomy Satellite) was a joint US-Dutch space telescope, the first serious infrared mission to observe from space, without the effects of Earth’s atmosphere. IRAS discovered that numerous ‘trails’ covered the sky. These ‘trails’ are dust-ridden paths left in the inner Solar System by comets, like a trail of breadcrumbs through space. One of those dust trails coincided with the Geminid meteor shower, and with… “asteroid” (3200) Phaethon. Apparently, Phaethon is the parent body, shedding particles that become Geminid meteors if they hit Earth’s atmosphere and burn up. If the particles don’t, they remain in the trail, circling the Sun.
(3200) Phaethon is, then, important as the mission target of JAXA’s DESTINY+ deep space probe. That’s “DESTINY+”, as in Demonstration and Experiment of Space Technology for INterplanetary voYage with Phaethon fLyby and dUst Science. One of the instruments aboard DESTINY+ is a dust counter, DDA (DESTINY+ Dust Analyzer). DDA is based on a design flown on the Stardust mission, to comet Wild 2. That’s right, an instrument to measure dust, originally around a comet, will fly to “asteroid” (3200) Phaethon.
As part of mission preparations, the target is being characterized as thoroughly as practical beforehand. The mission ops team doesn’t need any surprises, and the scientists using ground telescopes get to compare their ‘before’ data with ‘after’ (space-based, up-close, very-hi-res) data. In effect, DESTINY+ results will help ‘calibrate’ observations of comets, asteroids, and ‘other’ (active asteroids and other transition objects).
In the case of (3200) Phaethon specifically, the ‘object’ has an oblique axis- its ‘poles’ are strongly tilted, like Uranus and (134340) Pluto. But, unlike Uranus, Phaethon has an eccentric orbit- the orbit takes it far from the Sun, then up close. This gives a very strong seasonal effect. One side of Phaethon faces the Sun during the close, hot part of the orbit. The other side of Phaethon is in shadow during the close pass of the Sun, and remains cooler. This can’t be harmless. We are seeking any effects generated, on the hot side of Phaethon vs. the cooler side. And because of the eccentric orbit of Phaethon, and the limits of the DESTINY+ launcher and propulsion systems, DESTINY+ will make a very fast, brief flyby. The mission does not have the leeway to take long, leisurely camera sequences. Having some sort of pre-knowledge of Phaethon will then place the few DESTINY+ images in some sort of broader context.
Just a bunch of boring rocks, eh?