         let ecliptic = equatorial.toEclipticCoordinates()
         XCTAssertEqualWithAccuracy(ecliptic.lambda.value, 113.215630, accuracy: 0.01/3600.0)
         XCTAssertEqualWithAccuracy(ecliptic.beta.value, 6.684170, accuracy: 0.01/3600.0)
+        let eqBack = ecliptic.toEquatorialCoordinates()
+        XCTAssertEqualWithAccuracy(eqBack.rightAscension.value, equatorial.rightAscension.value, accuracy: 0.1/3600.0)
+        XCTAssertEqualWithAccuracy(eqBack.declination.value, equatorial.declination.value, accuracy: 0.1/3600.0)
     }
     
     func testEquatorial2Horizontal() { // p.95

        let galactic = equatorial.toGalacticCoordinates()
        XCTAssertEqualWithAccuracy(galactic.l.value, 12.9593, accuracy: 0.001)
        XCTAssertEqualWithAccuracy(galactic.b.value, 6.0463, accuracy: 0.001)
    }
    
}

        let horizontal = equatorial.toHorizontalCoordinates(forGeographicalCoordinates: geographic, julianDay: date.julianDay())
        XCTAssertEqualWithAccuracy(horizontal.altitude.value, 15.1249, accuracy: 0.001)
        XCTAssertEqualWithAccuracy(horizontal.azimuth.value, 68.0337, accuracy: 0.001)
        let eqBack = horizontal.toEquatorialCoordinates()
        XCTAssertEqualWithAccuracy(eqBack.rightAscension.value, equatorial.rightAscension.value, accuracy: 0.1/3600.0)
        XCTAssertEqualWithAccuracy(eqBack.declination.value, equatorial.declination.value, accuracy: 0.1/3600.0)
    }
    
    func testEquatorial2Galactic() { // p.95
