  The NASA Lucy mission is aimed at the study of the very interesting
population of Jupiter Trojans, considered as time capsules from the origin of
our solar system. During its journey, the mission will pass near a main belt
asteroid, Donaldjohanson. Recently, NASA has announced that a new asteroid in
the belt will also be visited by Lucy: 152830 Dinkinesh (1999 VD57). The main
goal of this work is to characterise this newly selected target, asteroid
Dinkinesh, in order to provide critical information to the mission team. To
achieve it, we have obtained visible spectra, colour photometry, and
time-series photometry of Dinkinesh, using several telescopes located at
different observatories. For the spectra we used the 10.4m Gran Telescopio
Canarias (GTC), in the island of La Palma (Spain); for the colour photometry
the 4.3m Lowell Discovery Telescope (LDT), near Happy Jack, Arizona (USA) was
used; and for the time-series photometry we used the 82cm IAC80 telescope
located in the island of Tenerife (Spain). Both visible spectrum and
reflectance values computed from colour photometry show that Dinkinesh is an
S-type asteroid, i.e., it is composed mainly of silicates and some metal.
According to observations done by the NEOWISE survey, S-type asteroids have
typical geometric albedo of $p_V$ = 0.223 $\pm$ 0.073. From our time-series
photometry, we obtained an asteroid mean magnitude $r'$ = 19.99 $\pm$ 0.05,
which provides an absolute magnitude $H_{r'}$ = 17.53 $\pm$ 0.07 assuming $G$ =
0.19 $\pm$ 0.25 for S-types. Using our colour-photometry, we transformed
$H_{r'}$ to $H_V$ = 17.48 $\pm$ 0.05. This value of absolute magnitude combined
with the geometric albedo provides a mean diameter for Dinkinesh of $\sim$900
m, ranging between a minimum size of 542 m and a maximum size of 1309 m.
