diff --git a/README.md b/README.md
index c88b7bd..13b3294 100644
--- a/README.md
+++ b/README.md
@@ -124,6 +124,22 @@ We suggest the user to run each simulation in a separate folder, that can be pla
             ./orbit9.x
             
 **NOTE.** You may want to run the program in background for long-term integrations.
+
+
+### Output files
+The output files for the orbital integration of the asteroids are the same as the one provided by the 
+original orbit9 code.
+
+In addition to the orbital integration, the modified orbit9 code provides the output files for the spin-axis 
+dynamics when the flag *enable_out* is set to 1. The output files are called 
+
+         <astname>.yorp
+
+and it provides 4 columns, representing:
+1. the output time (in years)
+2. the rotation period (in hours)
+3. the obliquity (in degrees)
+4. the semi-major axis drift due to Yarkovsky (in au/My).
    
 ### Run the test simulation
 The folder *tests/orbit9_yorp* contains the files to test a simulation that includes
diff --git a/tests/orbfit/epoch/410777.eq0 b/tests/orbfit/epoch/410777.eq0
index 5847a82..27666ca 100644
--- a/tests/orbfit/epoch/410777.eq0
+++ b/tests/orbfit/epoch/410777.eq0
@@ -4,23 +4,23 @@ refsys  = ECLM J2000     ! default reference system
 END_OF_HEADER
 410777
 ! Equinoctial elements: a, e*sin(LP), e*cos(LP), tan(i/2)*sin(LN), tan(i/2)*cos(LN), mean long.
- EQU   1.16258579991419E+00  -0.460780587309722   0.174893426578777    0.004546873094735    0.027005357832081 130.2149433096533
- MJD     56146.360960617 TDT
- MAG  22.134  0.150
-! RMS    1.96473E-09   2.98895E-08   5.56570E-08   6.52480E-09   4.94639E-08   5.61450E-06
-! EIG   2.84046E-10   3.77115E-09   1.37549E-08   2.39388E-08   4.96551E-08   1.13333E-07
-! WEA   0.00193  -0.23555   0.45263  -0.00008   0.04021   0.85908
- COV   3.860161481946468E-18 -1.446165963073374E-17  4.656822845390550E-17
- COV   1.821664976970862E-18 -5.907075447992529E-18  3.682275993571308E-17
- COV   8.933795320401931E-16 -1.305841352943879E-15  3.588417695120097E-17
- COV  -2.535854001407887E-16 -1.476485819588337E-13  3.097701994976310E-15
- COV   5.346289388090830E-17  2.106754334362823E-17  2.736504315540130E-13
- COV   4.257297281472898E-17  1.513509627075819E-16 -1.526753453281804E-15
- COV   2.446682165292112E-15  2.326849867690401E-14  3.152255413752462E-11
- NOR   1.226873664370155E+19  7.665131030671191E+17 -7.691614761816942E+17
- NOR   1.253841081615465E+17  1.043852799048019E+16  1.025147626692871E+16
- NOR   5.620974881710584E+16 -4.607629446026310E+16 -6.410417471291135E+15
- NOR   2.188687554135583E+15  6.604524414262104E+14  5.060145487149013E+16
- NOR  -1.577644806577004E+16  1.374226967551625E+14 -6.550602190972885E+14
- NOR   6.677124890538547E+16 -5.440786433786167E+15  1.140347934489098E+14
- NOR   9.190707863578328E+14  8.104493058181679E+12  8.799427002223816E+12
+ EQU   1.16267296532696E+00  -0.460663787149893   0.174881277291140    0.004551542480933    0.027004980226847  25.7135001289037
+ MJD     56013.440131620 TDT
+ MAG  22.130  0.150
+! RMS    2.04185E-09   3.16794E-08   6.08065E-08   6.78702E-09   5.56062E-08   6.08870E-06
+! EIG   3.19829E-10   3.77761E-09   1.30692E-08   2.33856E-08   5.58635E-08   1.23626E-07
+! WEA   0.00272  -0.23241   0.46139   0.00157   0.03830   0.85535
+ COV   4.169162701043839E-18 -1.575613095247293E-17  5.410558529866873E-17
+ COV   2.152240948132489E-18 -9.031385169561095E-18  8.884898855419340E-16
+ COV   1.003581986244237E-15 -1.541881189719501E-15  3.003470624508290E-17
+ COV  -3.099241892348508E-16 -1.738565027899039E-13  3.697434392752590E-15
+ COV   6.490030078113178E-17 -7.073003849329925E-18  3.340752601130692E-13
+ COV   4.606360963780009E-17  1.905728985028579E-16 -4.279273760580620E-16
+ COV   3.092046688674574E-15  2.664964672746937E-14  3.707226110912469E-11
+ NOR   9.651481524731505E+18  6.768856270706134E+17 -6.796850344075229E+17
+ NOR   1.097599830124688E+17  9.610409045856248E+15  9.062369656042902E+15
+ NOR   5.617325196682769E+16 -4.601854955571240E+16 -6.412826238343329E+15
+ NOR   2.206948159407462E+15  6.602451178273214E+14  5.035122539431070E+16
+ NOR  -1.574921120663447E+16  1.206500486267548E+14 -6.535286385660412E+14
+ NOR   6.651283311730663E+16 -5.439260899254842E+15  1.138966593927292E+14
+ NOR   8.360785526839552E+14  8.368481587875975E+12  8.790657650278620E+12