diff --git a/Tests/skyobjects/test_skypoint.h b/Tests/skyobjects/test_skypoint.h
--- a/Tests/skyobjects/test_skypoint.h
+++ b/Tests/skyobjects/test_skypoint.h
@@ -24,6 +24,7 @@
 #define UNIT_TEST
 
 #include "skyobjects/skypoint.h"
+#include <libnova/ln_types.h>
 
 /**
  * @class TestSkyPoint
@@ -33,14 +34,45 @@
 
 class TestSkyPoint : public QObject
 {
-    Q_OBJECT
+        Q_OBJECT
 
-  public:
-    TestSkyPoint() : QObject(){};
-    ~TestSkyPoint() override = default;
+    public:
+        TestSkyPoint();
+        ~TestSkyPoint() override;
 
-  private slots:
-    void testPrecession();
+    private:
+        void compare(QString msg, double ra1, double dec1, double ra2, double dec2, double err = 0.0001);
+        void compare(QString msg, SkyPoint * sp);
+        void compare(QString msg, SkyPoint * sp, SkyPoint * sp1);
+        void compare(QString msg, SkyPoint * sp, ln_equ_posn * lnp);
+        void ln_get_equ_nut(ln_equ_posn * posn, double jd, bool reverse = false);
+
+    private slots:
+        void testPrecession();
+
+        void compareNovas();
+
+        void testPrecess_data();
+        void testPrecess();
+
+        void testPrecessFromAnyEpoch_data();
+        void testPrecessFromAnyEpoch();
+
+        void testNutate_data();
+        void testNutate();
+
+        void testAberrate_data();
+        void testAberrate();
+
+        void testApparentCatalogue_data();
+        void testApparentCatalogue();
+
+        void compareSkyPointLibNova_data();
+        void compareSkyPointLibNova();
+
+    private:
+        bool useRelativistic {false};
 };
 
+
 #endif
diff --git a/Tests/skyobjects/test_skypoint.cpp b/Tests/skyobjects/test_skypoint.cpp
--- a/Tests/skyobjects/test_skypoint.cpp
+++ b/Tests/skyobjects/test_skypoint.cpp
@@ -20,15 +20,32 @@
 #include "ksnumbers.h"
 #include "time/kstarsdatetime.h"
 #include "auxiliary/dms.h"
+#include "Options.h"
+//#include <libnova/julian_day.h>
+//#include <libnova/precession.h>
+//#include <libnova/aberration.h>
+//#include <libnova/nutation.h>
+#include <libnova/libnova.h>
+
+TestSkyPoint::TestSkyPoint() : QObject()
+{
+    useRelativistic = Options::useRelativistic();
+}
+
+TestSkyPoint::~TestSkyPoint()
+{
+    Options::setUseRelativistic(useRelativistic);
+}
 
 void TestSkyPoint::testPrecession()
 {
     /*
      * NOTE: These test cases were picked randomly and generated using
      * https://ned.ipac.caltech.edu/forms/calculator.html
      */
 
-    auto verify = [](const SkyPoint &p, const double targetRA, const double targetDec, const double tolerance) {
+    auto verify = [](const SkyPoint & p, const double targetRA, const double targetDec, const double tolerance)
+    {
         qDebug() << p.ra().toHMSString() << " " << p.dec().toDMSString();
         QVERIFY(fabs(p.ra().Degrees() - targetRA) < tolerance * 15.);
         QVERIFY(fabs(p.dec().Degrees() - targetDec) < tolerance);
@@ -93,4 +110,445 @@
     verify(p, 169.71785991, 45.30132855, arcsecPrecision);
 }
 
+void TestSkyPoint::compareNovas()
+{
+    Options::setUseRelativistic(false);
+
+    KStarsDateTime kdt = KStarsDateTime::currentDateTimeUtc();
+    long double jd = kdt.djd();
+
+    double lnJd = ln_get_julian_from_sys();
+    // compare JD provided by KStarsDateTime and libnova
+    qDebug() << "KDT JD " << static_cast<double>(jd) << "  LN JD " << lnJd << " Diff " << (static_cast<double>
+             (jd) - lnJd) * 86400 << "secs";
+    QVERIFY(fabs(static_cast<double>(jd) - lnJd) * 86400 < 1);
+
+    qDebug() << "Check conversion in Align";
+    // the align process is a bit like this:
+    // Catalogue position
+    SkyPoint target(4, 20); // ra in hours, dec in degrees
+
+    // transform to JNow in EKOS
+    // this is wrong because aberration and nutation are handled incorrectly
+    target.apparentCoord(static_cast<long double>(J2000), jd);
+    double raN = target.ra().Degrees();
+    double decN = target.dec().Degrees();
+    qDebug() << "SkyPoint J2000 to JNow " << raN << ", " << decN;
+
+    // should be:
+    // remove aberration
+
+    // remove nutation
+
+    // this is passed to the CCD simulator where it is transformed to J2K using libnova
+    ln_equ_posn JnowPos { 0, 0 }, J2kPos { 0, 0 };
+    JnowPos.ra = raN;
+    JnowPos.dec = decN;
+    ln_get_equ_prec2(&JnowPos, lnJd, JD2000, &J2kPos);
+    double ra0 = J2kPos.ra;
+    double dec0 = J2kPos.dec;
+    qDebug() << "Libnova JNow to J2000" << ra0 << ", " << dec0;
+
+    // this is used to generate a star image which is solved
+    // assume this solve is perfect
+
+    // Align converts this J2000 position back to JNow:
+    SkyPoint ac(ra0 / 15., dec0);
+    ac.apparentCoord(static_cast<long double>(J2000), jd);
+    double ran2 = ac.ra().Degrees();
+    double decn2 = ac.dec().Degrees();
+    qDebug() << "SkyPoint J2000 to JNow" << ran2 << ", " << decn2;
+    // get the error, this appears as the align error
+    qDebug() << "Error " << (raN - ran2) * 3600 << ", " << (decN - decn2) * 3600;
+
+    // check the difference
+    //QVERIFY(fabs(decN - decn2) * 3600. < 1);
+    //QVERIFY(fabs(raN - ran2) * 3600. < 1);
+
+    qDebug();
+    qDebug() << "Using libnova throughout";
+    J2kPos.ra = 60;
+    J2kPos.dec = 20;
+    // convert to JNow
+    ln_get_equ_prec2(&J2kPos, JD2000, lnJd, &JnowPos);
+    qDebug() << "libnova J2000 to JNow " << JnowPos.ra << ", " << JnowPos.dec;
+    // convert to J2000
+    ln_get_equ_prec2(&JnowPos, lnJd, JD2000, &J2kPos);
+    qDebug() << " libnova JNow to J2000" << J2kPos.ra << ", " << J2kPos.dec;
+
+    // 'solve'
+
+    // convert back to Jnow
+    ln_equ_posn Jnow2Pos { 0, 0 };
+    ln_get_equ_prec2(&J2kPos, JD2000, lnJd, &Jnow2Pos);
+    qDebug() << "libnova J2000 to JNow " << Jnow2Pos.ra << ", " << Jnow2Pos.dec;
+
+    qDebug() << "Error " << (JnowPos.ra - Jnow2Pos.ra) * 3600 << ", " << (JnowPos.dec - Jnow2Pos.dec) * 3600;
+
+    // Using SkyPoint won't help:
+    qDebug();
+    qDebug() << "using SkyPoint both ways";
+    // do the conversion from the previously computed JNow position
+    SkyPoint ccd;
+    ccd.setRA(raN / 15.);
+    ccd.setDec(decN);
+    KSNumbers num(jd);
+    ccd.deprecess(&num);
+    qDebug() << "SkyPoint Jnow to J2000 " << ccd.ra0().Degrees() << ", " << ccd.dec0().Degrees();
+    // and to Jnow
+    ccd.apparentCoord(static_cast<long double>(J2000), jd);
+    qDebug() << "SkyPoint J2000 to JNow " << ccd.ra().Degrees() << ", " << ccd.dec().Degrees();
+
+    qDebug() << "Error " << (raN - ccd.ra().Degrees()) * 3600 << ", " << (decN - ccd.dec().Degrees()) * 3600;
+
+    //QVERIFY(fabs(p.ra().Degrees() - targetRA) < tolerance * 15.);
+    //QVERIFY(fabs(p.dec().Degrees() - targetDec) < tolerance);
+
+    //qCDebug(KSTARS_EKOS_ALIGN) << "libnova errors " <<
+    //        (epochPos.ra - targetCoord.ra().Degrees()) * 3600. << "as, " << (epochPos.dec - targetCoord.dec().Degrees()) * 3600. << "as";
+
+
+    Options::setUseRelativistic(useRelativistic);
+}
+
+void TestSkyPoint::testPrecess_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+
+    QTest::newRow("normal") << 4.0 << 20.0;
+    QTest::newRow("south") << 15.0 << -35.0;
+    QTest::newRow("near Pole") << 22.0 << 85.0;
+    QTest::newRow("near S Pole") << 22.0 << -85.0;
+}
+
+void TestSkyPoint::testPrecess()
+{
+    auto jd = KStarsDateTime::currentDateTimeUtc().djd();
+    KSNumbers now(jd);
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+
+    sp = SkyPoint(Ra, Dec);
+
+    sp.precess(&now);
+
+    qDebug() << "precess dRa " << sp.ra0().Degrees() - sp.ra().Degrees() << ", dDec " << sp.dec0().Degrees() -
+             sp.dec().Degrees();
+
+    SkyPoint spn = sp.deprecess(&now);
+
+    compare("precess-deprecess ", sp.ra0().Degrees(), sp.dec0().Degrees(), spn.ra().Degrees(), spn.dec().Degrees());
+}
+
+void TestSkyPoint::testPrecessFromAnyEpoch_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+
+    QTest::newRow("normal") << 4.0 << 20.0;
+    QTest::newRow("south") << 15.0 << -35.0;
+    QTest::newRow("near Pole") << 22.0 << 85.0;
+    QTest::newRow("near S Pole") << 22.0 << -85.0;
+}
+
+void TestSkyPoint::testPrecessFromAnyEpoch()
+{
+    auto jd = KStarsDateTime::currentDateTimeUtc().djd();
+    KSNumbers now(jd);
+
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+    sp = SkyPoint(Ra, Dec);
+
+    sp.precessFromAnyEpoch(J2000L, jd);
+
+    qDebug() << "PFAE dRa " << sp.ra0().Degrees() - sp.ra().Degrees() << ", dDec " << sp.dec0().Degrees() - sp.dec().Degrees();
+
+    SkyPoint spn = SkyPoint(sp.ra(), sp.dec());
+    spn.precessFromAnyEpoch(jd, J2000L);
+
+    compare("dePFAE ", sp.ra0().Degrees(), sp.dec0().Degrees(), spn.ra().Degrees(), spn.dec().Degrees());
+}
+
+void TestSkyPoint::testNutate_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+
+    QTest::newRow("normal") << 4.0 << 20.0;
+    QTest::newRow("south") << 15.0 << -35.0;
+    QTest::newRow("near Pole") << 22.0 << 85.0;
+    QTest::newRow("near S Pole") << 22.0 << -85.0;
+}
+
+void TestSkyPoint::testNutate()
+{
+    long double jd = KStarsDateTime::currentDateTimeUtc().djd();
+    KSNumbers now(jd);
+
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+    sp = SkyPoint(Ra, Dec);
+
+    sp.nutate(&now);
+
+    qDebug() << "nutate dRa " << sp.ra0().Degrees() - sp.ra().Degrees() << ", dDec " << sp.dec0().Degrees() -
+             sp.dec().Degrees();
+
+    sp.nutate(&now, true);
+
+    compare("nutate-denutate", &sp);
+}
+
+void TestSkyPoint::testAberrate_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+
+    QTest::newRow("normal") << 4.0 << 20.0;
+    QTest::newRow("south") << 15.0 << -35.0;
+    QTest::newRow("near Pole") << 22.0 << 85.0;
+    QTest::newRow("near S Pole") << 22.0 << -85.0;
+}
+
+void TestSkyPoint::testAberrate()
+{
+    long double jd = KStarsDateTime::epochToJd(2028.3);
+    KSNumbers now(jd);
+
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+    sp = SkyPoint(Ra, Dec);
+
+    sp.aberrate(&now);
+
+    // deaberrate
+    sp.aberrate(&now, true);
+
+    compare("aberrate-deaberrate", &sp);
+}
+
+// test results obtained using the ASCOM Transform component
+// to convert from J2000 to Apparent
+// this uses SOFA so should be fairly good
+void TestSkyPoint::testApparentCatalogue_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+    QTest::addColumn<double>("RaOut");
+    QTest::addColumn<double>("DecOut");
+
+    QTest::newRow("Apparent") << 4.0 << 20.0 << 4.0274 << 20.0791;
+    QTest::newRow("south") << 10.0 << -35.0 << 10.0208 << -35.1418;
+    QTest::newRow("south") << 10.0 << -55.0 << 10.01698 << -55.14256;
+    QTest::newRow("near Pole") << 22.0 << 85.0 << 21.9601 << 85.1317;
+    QTest::newRow("near S Pole") << 15.0 << -85.0 << 15.1159 << -85.1112;
+}
+
+void TestSkyPoint::testApparentCatalogue()
+{
+    Options::setUseRelativistic(false);
+
+    //long double jd = KStarsDateTime::currentDateTimeUtc().djd();
+    auto dt = KStarsDateTime::fromString("2028-04-27T06:30");
+    long double jd = dt.djd();
+
+    double rjd = static_cast<double>(jd - J2000L);
+    //qDebug() << "DT " << dt.toString() << " JD " << static_cast<double>(jd) << " RJD " << rjd;
+
+    QVERIFY(fabs(rjd - 10343.771) < 0.1);
+
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+    sp = SkyPoint(Ra, Dec);
+
+    // J2000 catalogue to Apparent
+    sp.apparentCoord(J2000L, jd);
+    //    qDebug() << "apparent ra0 " << sp.ra0().Hours() << ", dec0 " << sp.dec0().Degrees() <<
+    //                " ra " << sp.ra().Hours() << ", dec " << sp.dec().Degrees();
+    QFETCH(double, RaOut);
+    QFETCH(double, DecOut);
+
+    // error relaxed as we are comparing with an extermal catalogue - suspicous!
+    compare("J2000 to aparrent", RaOut, DecOut, sp.ra().Hours(), sp.dec().Degrees(), 0.0015);
+
+    SkyPoint spn = SkyPoint(sp.ra(), sp.dec());
+    qDebug() << "spn ra0 " << spn.ra0().Degrees() << ", dec0 " << spn.dec0().Degrees() <<
+             " ra " << spn.ra().Degrees() << ", dec " << spn.dec().Degrees();
+
+    // apparent on jd to J2000Catalogue
+    spn.catalogueCoord(jd);
+
+    compare("J2K to app to catalogue", sp.ra0().Degrees(), sp.dec0().Degrees(), spn.ra0().Degrees(), spn.dec0().Degrees());
+}
+
+void TestSkyPoint::compareSkyPointLibNova_data()
+{
+    QTest::addColumn<double>("Ra");
+    QTest::addColumn<double>("Dec");
+    QTest::addColumn<double>("RaOut");
+    QTest::addColumn<double>("DecOut");
+
+    QTest::newRow("Apparent") << 4.0 << 20.0 << 4.0274 << 20.0791;
+    QTest::newRow("south") << 10.0 << -35.0 << 10.0208 << -35.1418;
+    QTest::newRow("south") << 10.0 << -55.0 << 10.01698 << -55.14256;
+    QTest::newRow("near Pole") << 22.0 << 85.0 << 21.9601 << 85.1317;
+    QTest::newRow("near S Pole") << 15.0 << -85.0 << 15.1159 << -85.1112;
+}
+void TestSkyPoint::compareSkyPointLibNova()
+{
+    // skypoint JD
+    auto dt = KStarsDateTime::fromString("2028-04-27T06:30");
+    long double ljd = dt.djd();
+    double jd = static_cast<double>(ljd);
+
+    SkyPoint sp;
+    QFETCH(double, Ra);
+    QFETCH(double, Dec);
+    sp = SkyPoint(Ra, Dec);
+    ln_equ_posn LnPos { Ra * 15.0, Dec }, observed { 0, 0 }, J2000Pos { 0, 0 };
+
+    ln_equ_posn tempPosn;
+
+    KSNumbers num(ljd);
+
+    // apply precession from J2000 to jd
+    ln_get_equ_prec2(&LnPos, JD2000, jd, &tempPosn);
+    SkyPoint spp = sp;
+    spp.precessFromAnyEpoch(J2000L, ljd);
+    compare("precess", spp.ra().Degrees(), spp.dec().Degrees(), tempPosn.ra, tempPosn.dec);
+
+    // apply nutation (needs new function)
+    ln_get_equ_nut(&tempPosn, jd);
+    SkyPoint spn = spp;
+    spn.nutate(&num);
+    compare("nutate", spn.ra().Degrees(), spn.dec().Degrees(), tempPosn.ra, tempPosn.dec);
+
+    // apply aberration
+    ln_get_equ_aber(&tempPosn, jd, &observed);
+    SkyPoint spa = spn;
+    spa.aberrate(&num);
+    compare("aberrate", spa.ra().Degrees(), spa.dec().Degrees(), observed.ra, observed.dec);
+
+    sp.apparentCoord(J2000L, ljd);
+
+    // compare sp and observed with each other
+    compare("sp and LN ", sp.ra().Degrees(), sp.dec().Degrees(), observed.ra, observed.dec);
+    QFETCH(double, RaOut);
+    QFETCH(double, DecOut);
+    // compare sp with expected, use degrees
+    compare("sp expected ", RaOut * 15., DecOut, sp.ra().Degrees(), sp.Dec.Degrees(), 0.0005);
+    // compare ln with expected
+    compare("ln expected ", RaOut * 15, DecOut, observed.ra, observed.dec, 0.0005);
+
+    // now to J2000
+
+    // remove the aberration
+    ln_get_equ_aber(&observed, jd, &tempPosn);
+    // this conversion has added the aberration, we want to subtract it
+    tempPosn.ra = observed.ra - (tempPosn.ra - observed.ra);
+    tempPosn.dec = observed.dec * 2 - tempPosn.dec;
+    //sp.aberrate(&num, true);
+
+
+    // remove the nutation
+    ln_get_equ_nut(&tempPosn, jd, true);
+
+    //sp.nutate(&num, true);
+
+    // precess from now to J2000
+    ln_get_equ_prec2(&tempPosn, jd, JD2000, &J2000Pos);
+
+    // the start position needs to be in RA0,Dec0
+    //sp.RA0 = sp.RA;
+    //sp.Dec0 = sp.Dec;
+    // from now to J2000
+    //sp.precessFromAnyEpoch(jd, J2000L);
+    // the J2000 position is in RA,Dec, move to RA0, Dec0
+    //sp.RA0 = sp.RA;
+    //sp.Dec0 = sp.Dec;
+    //sp.lastPrecessJD = J2000;
+
+    sp.catalogueCoord(ljd);
+
+    //compare sp and the j2000Pos with each other and the original
+    compare("Round trip ", &sp, &J2000Pos);
+    compare("original", Ra, Dec, sp.RA0.Hours(), sp.Dec0.Degrees());
+}
+
+void TestSkyPoint::compare(QString msg, SkyPoint *sp, SkyPoint *sp1)
+{
+    compare(msg, sp->ra0().Degrees(), sp->dec0().Degrees(), sp1->ra().Degrees(), sp1->dec().Degrees());
+}
+
+void TestSkyPoint::compare(QString msg, SkyPoint *sp, ln_equ_posn *lnp)
+{
+    compare(msg, sp->ra0().Degrees(), sp->dec0().Degrees(), lnp->ra, lnp->dec);
+}
+
+void TestSkyPoint::compare(QString msg, SkyPoint *sp)
+{
+    compare(msg, sp->ra0().Degrees(), sp->dec0().Degrees(), sp->ra().Degrees(), sp->dec().Degrees());
+}
+
+void TestSkyPoint::compare(QString msg, double ra1, double dec1, double ra2, double dec2, double err)
+{
+    qDebug(qPrintable(QString("%1 pos1 %2, %3 pos2 %4, %5 errors %6, %7 secs").arg(msg)
+                      .arg(ra1).arg(dec1).arg(ra2).arg(dec2)
+                      .arg((ra1 - ra2) * 3600.0, 6, 'f', 1).arg((dec1 - dec2) * 3600., 6, 'f', 1)));
+    //QString str;
+    //str.sprintf("%s pos1 %f, %f pos2 %f, %f errors %.1f, %.1f sec", msg.data(), ra1, dec1, ra2, dec2, (ra1 - ra2) *3600, (dec1 - dec2) * 3600 );
+    //qDebug() << str;// << msg << "SP " << ra1 << ", " << dec1 << " Sp0 " << ra2 << ", " << dec2
+    //<< " errors " << ((ra1 - ra2) * 3600) << ", " << ((dec1 - dec2) * 3600) << " arcsec";
+
+    double errRa = err / cos(dec1 * M_PI / 180.0);
+
+    QVERIFY2(fabs(ra1 - ra2) < errRa, qPrintable(QString("Ra %1, %2 error %3").arg(ra1).arg(ra2).arg(((ra1 - ra2) * 3600.0), 6,
+             'f', 1)));
+    QVERIFY2(fabs(dec1 - dec2) < err, qPrintable(QString("Dec %1, %2 error %3").arg(dec1).arg(dec2).arg((dec1 - dec2) * 3600.,
+             6, 'f', 1)));
+}
+
+// apply or remove nutation
+void TestSkyPoint::ln_get_equ_nut(ln_equ_posn *posn, double jd, bool reverse)
+{
+    // code lifted from libnova ln_get_equ_nut
+    // with the option to add or remove nutation
+    struct ln_nutation nut;
+    ln_get_nutation (jd, &nut);
+
+    double mean_ra, mean_dec, delta_ra, delta_dec;
+
+    mean_ra = ln_deg_to_rad(posn->ra);
+    mean_dec = ln_deg_to_rad(posn->dec);
+
+    // Equ 22.1
+
+    double nut_ecliptic = ln_deg_to_rad(nut.ecliptic + nut.obliquity);
+    double sin_ecliptic = sin(nut_ecliptic);
+
+    double sin_ra = sin(mean_ra);
+    double cos_ra = cos(mean_ra);
+
+    double tan_dec = tan(mean_dec);
+
+    delta_ra = (cos (nut_ecliptic) + sin_ecliptic * sin_ra * tan_dec) * nut.longitude - cos_ra * tan_dec * nut.obliquity;
+    delta_dec = (sin_ecliptic * cos_ra) * nut.longitude + sin_ra * nut.obliquity;
+
+    // the sign changed to remove nutation
+    if (reverse)
+    {
+        delta_ra = -delta_ra;
+        delta_dec = -delta_dec;
+    }
+    posn->ra += delta_ra;
+    posn->dec += delta_dec;
+}
+
 QTEST_GUILESS_MAIN(TestSkyPoint)
diff --git a/kstars/dialogs/focusdialog.cpp b/kstars/dialogs/focusdialog.cpp
--- a/kstars/dialogs/focusdialog.cpp
+++ b/kstars/dialogs/focusdialog.cpp
@@ -81,7 +81,8 @@
 
     if (center)
     {
-        center->deprecess(KStarsData::Instance()->updateNum());
+        //center->deprecess(KStarsData::Instance()->updateNum());
+        center->catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
         fd->raBox->setDMS(center->ra().toHMSString());
         fd->decBox->setDMS(center->dec().toDMSString());
 
@@ -152,7 +153,8 @@
         {
             Point->setRA(ra);
             Point->setDec(dec);
-            Point->deprecess(KStarsData::Instance()->updateNum());
+            //Point->deprecess(KStarsData::Instance()->updateNum());
+            Point->catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
         }
         else
         {
diff --git a/kstars/ekos/mount/mount.cpp b/kstars/ekos/mount/mount.cpp
--- a/kstars/ekos/mount/mount.cpp
+++ b/kstars/ekos/mount/mount.cpp
@@ -516,7 +516,7 @@
             if (currentTelescope->isJ2000() == false)
             {
                 SkyPoint J2000Coord(telescopeCoord.ra(), telescopeCoord.dec());
-                J2000Coord.apparentCoord(KStars::Instance()->data()->ut().djd(), static_cast<long double>(J2000));
+                J2000Coord.catalogueCoord(KStars::Instance()->data()->ut().djd());
                 //J2000Coord.precessFromAnyEpoch(KStars::Instance()->data()->ut().djd(), static_cast<long double>(J2000));
                 telescopeCoord.setRA0(J2000Coord.ra());
                 telescopeCoord.setDec0(J2000Coord.dec());
diff --git a/kstars/ekos/scheduler/scheduler.cpp b/kstars/ekos/scheduler/scheduler.cpp
--- a/kstars/ekos/scheduler/scheduler.cpp
+++ b/kstars/ekos/scheduler/scheduler.cpp
@@ -225,7 +225,8 @@
     connect(copySkyCenterB, &QPushButton::clicked, this, [this]()
     {
         SkyPoint center = SkyMap::Instance()->getCenterPoint();
-        center.deprecess(KStarsData::Instance()->updateNum());
+        //center.deprecess(KStarsData::Instance()->updateNum());
+        center.catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
         raBox->setDMS(center.ra0().toHMSString());
         decBox->setDMS(center.dec0().toDMSString());
     });
diff --git a/kstars/hips/hipsrenderer.cpp b/kstars/hips/hipsrenderer.cpp
--- a/kstars/hips/hipsrenderer.cpp
+++ b/kstars/hips/hipsrenderer.cpp
@@ -58,7 +58,8 @@
   m_size = 0;
 
   SkyPoint center = SkyMap::Instance()->getCenterPoint();
-  center.deprecess(KStarsData::Instance()->updateNum());
+  //center.deprecess(KStarsData::Instance()->updateNum());
+  center.catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
 
   double ra = center.ra0().radians();
   double de = center.dec0().radians();
diff --git a/kstars/indi/inditelescope.cpp b/kstars/indi/inditelescope.cpp
--- a/kstars/indi/inditelescope.cpp
+++ b/kstars/indi/inditelescope.cpp
@@ -573,7 +573,7 @@
         case INDI_FIND_TELESCOPE:
         {
             SkyPoint J2000Coord(currentCoord.ra(), currentCoord.dec());
-            J2000Coord.apparentCoord(KStars::Instance()->data()->ut().djd(), static_cast<long double>(J2000));
+            J2000Coord.catalogueCoord(KStars::Instance()->data()->ut().djd());
             currentCoord.setRA0(J2000Coord.ra());
             currentCoord.setDec0(J2000Coord.dec());
             double maxrad = 1000.0 / Options::zoomFactor();
@@ -590,7 +590,7 @@
                     currentCoord.angularDistanceTo(KStars::Instance()->map()->focus()).Degrees() > 0.5)
             {
                 SkyPoint J2000Coord(currentCoord.ra(), currentCoord.dec());
-                J2000Coord.apparentCoord(KStars::Instance()->data()->ut().djd(), static_cast<long double>(J2000));
+                J2000Coord.catalogueCoord(KStars::Instance()->data()->ut().djd());
                 currentCoord.setRA0(J2000Coord.ra());
                 currentCoord.setDec0(J2000Coord.dec());
                 //KStars::Instance()->map()->setClickedPoint(&currentCoord);
@@ -768,7 +768,7 @@
             {
                 ScopeTarget->setRA0(ScopeTarget->ra());
                 ScopeTarget->setDec0(ScopeTarget->dec());
-                ScopeTarget->apparentCoord( KStars::Instance()->data()->ut().djd(), static_cast<long double>(J2000));
+                ScopeTarget->catalogueCoord( KStars::Instance()->data()->ut().djd());
                 ra = ScopeTarget->ra();
                 de = ScopeTarget->dec();
             }
diff --git a/kstars/kstarsactions.cpp b/kstars/kstarsactions.cpp
--- a/kstars/kstarsactions.cpp
+++ b/kstars/kstarsactions.cpp
@@ -1895,7 +1895,8 @@
     if (Options::showJ2000RADecField())
     {
         SkyPoint p0;
-        p0        = p->deprecess(KStarsData::Instance()->updateNum()); // deprecess to update RA0/Dec0 from RA/Dec
+        //p0        = p->deprecess(KStarsData::Instance()->updateNum()); // deprecess to update RA0/Dec0 from RA/Dec
+        p0 = p->catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
         QString s = QString("%1, %2 (J2000)")
                     .arg(p0.ra().toHMSString(),
                          p0.dec().toDMSString(true)); //true: force +/- symbol
diff --git a/kstars/skycomponents/flagcomponent.cpp b/kstars/skycomponents/flagcomponent.cpp
--- a/kstars/skycomponents/flagcomponent.cpp
+++ b/kstars/skycomponents/flagcomponent.cpp
@@ -358,7 +358,7 @@
     if (dt.djd() == J2000)
         return;
 
-    p->apparentCoord(dt.djd(), J2000);
+    p->catalogueCoord(dt.djd());
 
     // Store J2000 coords in RA0, DEC0
     p->setRA0(p->ra());
diff --git a/kstars/skycomponents/skymesh.cpp b/kstars/skycomponents/skymesh.cpp
--- a/kstars/skycomponents/skymesh.cpp
+++ b/kstars/skycomponents/skymesh.cpp
@@ -68,7 +68,7 @@
     // FIXME: simple copying leads to incorrect results because RA0 && dec0 are both zero sometimes
     SkyPoint p1(p0->ra(), p0->dec());
     long double now = data->updateNum()->julianDay();
-    p1.apparentCoord(now, J2000);
+    p1.catalogueCoord(now);
 
     if (radius == 1.0)
     {
diff --git a/kstars/skymap.cpp b/kstars/skymap.cpp
--- a/kstars/skymap.cpp
+++ b/kstars/skymap.cpp
@@ -463,7 +463,8 @@
     }
     else
     {
-        SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        //SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        SkyPoint deprecessedPoint = clickedPoint()->catalogueCoord(data->updateNum()->julianDay());
         ra                        = deprecessedPoint.ra();
         dec                       = deprecessedPoint.dec();
         urlstring                 = KSDssDownloader::getDSSURL(ra, dec); // Use default size for non-objects
@@ -495,7 +496,9 @@
     }
     else
     {
-        SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        //SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        SkyPoint deprecessedPoint = clickedPoint()->catalogueCoord(data->updateNum()->julianDay());
+        deprecessedPoint.catalogueCoord(data->updateNum()->julianDay());
         deprecessedPoint.EquatorialToHorizontal(data->lst(), data->geo()->lat());
 
         J2000RA = deprecessedPoint.ra0();
@@ -535,7 +538,9 @@
     }
     else
     {
-        SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        //SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        SkyPoint deprecessedPoint = clickedPoint()->catalogueCoord(data->updateNum()->julianDay());
+        deprecessedPoint.catalogueCoord(data->updateNum()->julianDay());
         ra                        = deprecessedPoint.ra();
         dec                       = deprecessedPoint.dec();
     }
@@ -729,7 +734,9 @@
     }
     else
     {
-        SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        //SkyPoint deprecessedPoint = clickedPoint()->deprecess(data->updateNum());
+        SkyPoint deprecessedPoint = clickedPoint()->catalogueCoord(data->updateNum()->julianDay());
+        deprecessedPoint.catalogueCoord(data->updateNum()->julianDay());
         J2000RA                   = deprecessedPoint.ra();
         J2000DE                   = deprecessedPoint.dec();
     }
diff --git a/kstars/skyobjects/jupitermoons.cpp b/kstars/skyobjects/jupitermoons.cpp
--- a/kstars/skyobjects/jupitermoons.cpp
+++ b/kstars/skyobjects/jupitermoons.cpp
@@ -330,8 +330,9 @@
         Moon[i]->setRA(Jupiter->ra().Hours() - 0.011 * (XP[i] * cos(pa) - YP[i] * sin(pa)) / 15.0);
         Moon[i]->setDec(Jupiter->dec().Degrees() - 0.011 * (XP[i] * sin(pa) + YP[i] * cos(pa)));
 
-        SkyPoint p = Moon[i]->deprecess(
-            num); // FIXME: Really, we should also denutate. Actually, we should also be aberrating these above, right?
+        //SkyPoint p = Moon[i]->deprecess(
+        //    num); // FIXME: Really, we should also denutate. Actually, we should also be aberrating these above, right?
+        SkyPoint p = Moon[i]->catalogueCoord(num->julianDay());
         Moon[i]->setRA0(
             p.ra()); // Just to be sure, in case deprecess doesn't set it already because RA0 was not NaN or something.
         Moon[i]->setDec0(p.dec());
diff --git a/kstars/skyobjects/skypoint.h b/kstars/skyobjects/skypoint.h
--- a/kstars/skyobjects/skypoint.h
+++ b/kstars/skyobjects/skypoint.h
@@ -19,8 +19,13 @@
 
 #pragma once
 
+#define USE_LIBNOVA
+
 #include "cachingdms.h"
 #include "kstarsdatetime.h"
+#ifdef USE_LIBNOVA
+#include <libnova/libnova.h>
+#endif
 
 #include <QList>
 #ifndef KSTARS_LITE
@@ -318,12 +323,26 @@
     void apparentCoord(long double jd0, long double jdf);
 
     /**
-     * Determine the effects of nutation for this SkyPoint.
+     * Computes the J2000.0 catalogue coordinates for this SkyPoint using the epoch
+     * removing aberration, nutation and precession
+     * Catalogue coordinates are in Ra0, Dec0
+     *
+     * @brief catalogueCoord converts observed to J2000 using epoch jdf
+     * @param jdf Julian Day which identifies the current epoch
+     * @return SpyPoint containing J2000 coordinates
+     */
+
+    SkyPoint catalogueCoord(long double jdf);
+
+
+    /**
+     * Apply the effects of nutation to this SkyPoint.
      *
      * @param num pointer to KSNumbers object containing current values of
      * time-dependent variables.
+     * @param reverse bool, if true the nutation is removed
      */
-    void nutate(const KSNumbers *num);
+    void nutate(const KSNumbers *num, const bool reverse = false);
 
     /**
      * @short Check if this sky point is close enough to the sun for
@@ -355,8 +374,9 @@
      *
      * @param num pointer to KSNumbers object containing current values of
      * time-dependent variables.
+     * @param reverse bool, if true the aberration is removed.
      */
-    void aberrate(const KSNumbers *num);
+    void aberrate(const KSNumbers *num, bool reverse = false);
 
     /**
      * General case of precession. It precess from an original epoch to a
@@ -648,7 +668,12 @@
     dms Alt, Az;
     static KSSun *m_Sun;
 
-  protected:
+
+    // long version of these epochs
+#define J2000L          2451545.0L   //Julian Date for noon on Jan 1, 2000 (epoch J2000)
+#define B1950L          2433282.4235L // Julian date for Jan 0.9235, 1950
+
+protected:
     double lastPrecessJD { 0 }; // JD at which the last coordinate  (see updateCoords) for this SkyPoint was done
 };
 
diff --git a/kstars/skyobjects/skypoint.cpp b/kstars/skyobjects/skypoint.cpp
--- a/kstars/skyobjects/skypoint.cpp
+++ b/kstars/skyobjects/skypoint.cpp
@@ -251,17 +251,50 @@
             (!std::isnan(Dec0.Degrees()) && fabs(Dec0.Degrees()) > 90.0))
     {
         // We have invalid RA0 and Dec0, so set them if epoch = J2000. Otherwise, do not touch.
-        if (epoch == J2000)
+        if (epoch == J2000L)
         {
             RA0  = p1.ra();
             Dec0 = p1.dec();
         }
     }
     return p1;
 }
 
-void SkyPoint::nutate(const KSNumbers *num)
+void SkyPoint::nutate(const KSNumbers *num, const bool reverse)
 {
+#ifdef USE_LIBNOVA
+    // code lifted from libnova ln_get_equ_nut
+    // with the option to add or remove nutation
+    struct ln_nutation nut;
+    ln_get_nutation (num->julianDay(), &nut);
+
+    double mean_ra, mean_dec, delta_ra, delta_dec;
+
+    mean_ra = RA.radians();
+    mean_dec = Dec.radians();
+
+    // Equ 22.1
+
+    double nut_ecliptic = ln_deg_to_rad(nut.ecliptic + nut.obliquity);
+    double sin_ecliptic = sin(nut_ecliptic);
+
+    double sin_ra = sin(mean_ra);
+    double cos_ra = cos(mean_ra);
+
+    double tan_dec = tan(mean_dec);
+
+    delta_ra = (cos (nut_ecliptic) + sin_ecliptic * sin_ra * tan_dec) * nut.longitude - cos_ra * tan_dec * nut.obliquity;
+    delta_dec = (sin_ecliptic * cos_ra) * nut.longitude + sin_ra * nut.obliquity;
+
+    // the sign changed to remove nutation
+    if (reverse)
+    {
+        delta_ra = -delta_ra;
+        delta_dec = -delta_dec;
+    }
+    RA.setD(RA.Degrees() + delta_ra);
+    Dec.setD(Dec.Degrees() + delta_dec);
+#else
     double cosRA, sinRA, cosDec, sinDec, tanDec;
     double cosOb, sinOb;
 
@@ -278,18 +311,34 @@
         double dRA  = num->dEcLong() * (cosOb + sinOb * sinRA * tanDec) - num->dObliq() * cosRA * tanDec;
         double dDec = num->dEcLong() * (sinOb * cosRA) + num->dObliq() * sinRA;
 
+        if (reverse)
+        {
+            dRA = -dRA;
+            dDec = -dDec;
+        }
         RA.setD(RA.Degrees() + dRA);
         Dec.setD(Dec.Degrees() + dDec);
     }
     else //exact method
     {
+        // TODO apply reverse test above 80 degrees
         dms EcLong, EcLat;
         findEcliptic(num->obliquity(), EcLong, EcLat);
 
-        //Add dEcLong to the Ecliptic Longitude
-        dms newLong(EcLong.Degrees() + num->dEcLong());
-        setFromEcliptic(num->obliquity(), newLong, EcLat);
+        if (reverse)
+        {
+            //Subtract dEcLong from the Ecliptic Longitude
+            dms newLong(EcLong.Degrees() - num->dEcLong());
+            setFromEcliptic(num->obliquity(), newLong, EcLat);
+        }
+        else
+        {
+            //Add dEcLong to the Ecliptic Longitude
+            dms newLong(EcLong.Degrees() + num->dEcLong());
+            setFromEcliptic(num->obliquity(), newLong, EcLat);
+        }
     }
+#endif
 }
 
 SkyPoint SkyPoint::moveAway(const SkyPoint &from, double dist) const
@@ -375,8 +424,24 @@
     return true;
 }
 
-void SkyPoint::aberrate(const KSNumbers *num)
+void SkyPoint::aberrate(const KSNumbers *num, bool reverse)
 {
+#ifdef USE_LIBNOVA
+    ln_equ_posn pos { RA.Degrees(), Dec.Degrees() };
+    ln_equ_posn abPos { 0, 0 };
+    ln_get_equ_aber(&pos, num->julianDay(),&abPos);
+    if (reverse)
+    {
+        RA.setD(RA.Degrees() * 2 - abPos.ra);
+        Dec.setD(Dec.Degrees() * 2 - abPos.dec);
+    }
+    else
+    {
+        RA.setD(abPos.ra);
+        Dec.setD(abPos.dec);
+    }
+
+#else
     double cosRA, sinRA, cosDec, sinDec;
     double cosOb, sinOb, cosL, sinL, cosP, sinP;
 
@@ -403,8 +468,14 @@
     double dDec =
         K * (sinRA * (sinOb * cosDec - cosOb * sinDec) * (e * cosP - cosL) + cosRA * sinDec * (e * sinP - sinL));
 
+    if (reverse)
+    {
+        dRA = -dRA;
+        dDec = -dDec;
+    }
     RA.setD(RA.Degrees() + dRA);
     Dec.setD(Dec.Degrees() + dDec);
+#endif
 }
 
 // Note: This method is one of the major rate determining factors in how fast the map pans / zooms in or out
@@ -465,19 +536,19 @@
     RA.SinCos(sinRA, cosRA);
     Dec.SinCos(sinDec, cosDec);
 
-    if (jd0 == B1950)
+    if (jd0 == B1950L)
     {
         B1950ToJ2000();
-        jd0 = J2000;
+        jd0 = J2000L;
         RA.SinCos(sinRA, cosRA);
         Dec.SinCos(sinDec, cosDec);
     }
 
     if (jd0 != jdf)
     {
         // The original coordinate is referred to the FK5 system and
         // is NOT J2000.
-        if (jd0 != J2000)
+        if (jd0 != J2000L)
         {
             //v is a column vector representing input coordinates.
             v[0] = cosRA * cosDec;
@@ -502,7 +573,7 @@
             s[2] = sinDec;
         }
 
-        if (jdf == B1950)
+        if (jdf == B1950L)
         {
             RA.setRadians(atan2(s[1], s[0]));
             Dec.setRadians(asin(s[2]));
@@ -536,6 +607,31 @@
     aberrate(&num);
 }
 
+SkyPoint SkyPoint::catalogueCoord(long double jdf)
+{
+    KSNumbers num(jdf);
+
+    // remove abberation
+    aberrate(&num, true);
+
+    // remove nutation
+    nutate(&num, true);
+
+    // remove precession
+    // the start position needs to be in RA0,Dec0
+    RA0 = RA;
+    Dec0 = Dec;
+    // from now to J2000
+    precessFromAnyEpoch(jdf, static_cast<long double>(J2000));
+    // the J2000 position is in RA,Dec, move to RA0, Dec0
+    RA0 = RA;
+    Dec0 = Dec;
+    lastPrecessJD = J2000;
+
+    SkyPoint sp(RA0, Dec0);
+    return sp;
+}
+
 void SkyPoint::Equatorial1950ToGalactic(dms &galLong, dms &galLat)
 {
     double a = 192.25;
@@ -581,7 +677,7 @@
     double v[3], s[3];
 
     // 1984 January 1 0h
-    KSNumbers num(2445700.5);
+    KSNumbers num(2445700.5L);
 
     // Eterms due to aberration
     addEterms();
@@ -627,7 +723,7 @@
     double v[3], s[3];
 
     // 1984 January 1 0h
-    KSNumbers num(2445700.5);
+    KSNumbers num(2445700.5L);
 
     RA.SinCos(sinRA, cosRA);
     Dec.SinCos(sinDec, cosDec);
@@ -757,7 +853,7 @@
     SkyPoint aux;
     aux.set(RA0, Dec0);
 
-    aux.precessFromAnyEpoch(jd0, J2000);
+    aux.precessFromAnyEpoch(jd0, J2000L);
 
     aux.ra().SinCos(sinRA, cosRA);
     aux.dec().SinCos(sinDec, cosDec);
@@ -803,7 +899,7 @@
 
     SkyPoint aux(RA0, Dec0);
 
-    aux.precessFromAnyEpoch(jd0, J2000);
+    aux.precessFromAnyEpoch(jd0, J2000L);
 
     aux.ra().SinCos(sinRA, cosRA);
     aux.dec().SinCos(sinDec, cosDec);
diff --git a/kstars/tools/altvstime.cpp b/kstars/tools/altvstime.cpp
--- a/kstars/tools/altvstime.cpp
+++ b/kstars/tools/altvstime.cpp
@@ -303,7 +303,8 @@
             if (jd != J2000)
             {
                 SkyPoint ptest(newRA, newDec);
-                ptest.precessFromAnyEpoch(jd, J2000);
+                //ptest.precessFromAnyEpoch(jd, J2000);
+                ptest.catalogueCoord(jd);
                 newRA.setH(ptest.ra().Hours());
                 newDec.setD(ptest.dec().Degrees());
             }
diff --git a/kstars/tools/starhopper.cpp b/kstars/tools/starhopper.cpp
--- a/kstars/tools/starhopper.cpp
+++ b/kstars/tools/starhopper.cpp
@@ -154,7 +154,8 @@
         // needs a lot of fixing to handle unprecessed and precessed,
         // equatorial and horizontal coordinates nicely
         SkyPoint *CurrentNode = const_cast<SkyPoint *>(curr_node);
-        CurrentNode->deprecess(KStarsData::Instance()->updateNum());
+        //CurrentNode->deprecess(KStarsData::Instance()->updateNum());
+        CurrentNode->catalogueCoord(KStarsData::Instance()->updateNum()->julianDay());
         //qCDebug(KSTARS) << "Calling starsInAperture";
         StarComponent::Instance()->starsInAperture(neighbors, *curr_node, fov, maglim);
         qCDebug(KSTARS) << "Choosing next node from a set of " << neighbors.count();