| Minorplanet: | yes |
| 1070 Tunica | |
| Background: |
|
| Discovered: | 1 September 1926 |
| Mpc Name: | (1070) Tunica |
| Alt Names: | 1926 RBA903 SA |
| Named After: | Petrorhagia |
| Epoch: | 4 September 2017 (JD 2458000.5) |
| Uncertainty: | 0 |
| Observation Arc: | 114.03 yr (41,649 days) |
| Perihelion: | 2.9764 AU |
| Semimajor: | 3.2323 AU |
| Eccentricity: | 0.0792 |
| Period: | 5.81 yr (2,123 days) |
| Mean Motion: | / day |
| Inclination: | 16.963° |
| Asc Node: | 165.32° |
| Arg Peri: | 189.81° |
| Dimensions: | km 33.79 km km km km km |
| Rotation: | h h |
| Albedo: | 0.057 |
| Abs Magnitude: | 10.60 10.7010.811.08 |
1070 Tunica, provisional designation, is a dark background asteroid from the outer regions of the asteroid belt, approximately 35 kilometers in diameter. It was discovered on 1 September 1926, by German astronomer Karl Reinmuth at the Heidelberg-Königstuhl State Observatory in southwest Germany. The asteroid was named after Petrorhagia, a flowering plant also known as "Tunica".
Tunica is a non-family asteroid from the main belt's background population. Conversely, it has also been considered a core member of the Ursula family. It orbits the Sun in the outer main-belt at a distance of 3.0–3.5 AU once every 5 years and 10 months (2,123 days; semi-major axis of 3.23 AU). Its orbit has an eccentricity of 0.08 and an inclination of 17° with respect to the ecliptic.
The body's observation arc begins with its identification as at Heidelberg in September 1903, or 23 years prior to its official discovery observation.
Tunica is an assumed C-type asteroid.
In May 2017, a rotational lightcurve of Tunica was obtained from photometric observations by French amateur astronomer René Roy. Lightcurve analysis gave a rotation period of 15.8 hours with a brightness variation of 0.24 magnitude . Another lightcurve obtained in the R-band by astronomers at the Palomar Transient Factory in February 2010 gave a period of 15.673 hours and an amplitude of 0.32 magnitude .
According to the surveys carried out by the Japanese Akari satellite and the NEOWISE mission of NASA's Wide-field Infrared Survey Explorer, Tunica measures between 33.77 and 44.135 kilometers in diameter and its surface has an albedo between 0.0476 and 0.076.
The Collaborative Asteroid Lightcurve Link assumes a standard albedo for carbonaceous asteroids of 0.057 and calculates a diameter of 33.79 kilometers based on an absolute magnitude of 11.08.
This minor planet was named after "Tunica" (Petrorhagia), a flowering plant derived from the common gillyflower.
Due to his many discoveries, Karl Reinmuth submitted a large list of 66 newly named asteroids in the early 1930s. The list covered his discoveries with numbers between and . This list also contained a sequence of 28 asteroids, starting with 1054 Forsytia, that were all named after plants, in particular flowering plants (also see list of minor planets named after animals and plants).