diff --git a/arttools/arttime.py b/arttools/arttime.py
index a86737f..12144fb 100755
--- a/arttools/arttime.py
+++ b/arttools/arttime.py
@@ -21,6 +21,10 @@ class MissionTime(object):
     def get(self):
         return self._missiontime
 
+    @property
+    def time(self):
+        return self._missiontime
+
     def __str__(self):
         return str(self._missiontime)    
 
@@ -45,6 +49,10 @@ class ArtDay(object):
     def get(self):
         return self._artday
 
+    @property
+    def time(self):
+        return self._artday
+
     def __str__(self):
         return str(self._artday)  
 
@@ -69,6 +77,10 @@ class MjdDay(object):
     def get(self):
         return self._mjd
 
+    @property
+    def time(self):
+        return self._mjd
+
     def __str__(self):
         return str(self._mjd)
 
@@ -96,6 +108,10 @@ class Dtime(object):
     def get(self):
         return self._dtime
 
+    @property
+    def time(self):
+        return self._dtime
+
     def __str__(self):
         return str(self._dtime)
 
@@ -129,7 +145,6 @@ class ArtTime(object):
         self._try_mjd(mjd)
         self._try_dtime_utc(datetime_utc)
         self._try_dtime_msk(datetime_msk)
-        self
 
         if self._has_value > 1:
             print('Error: ArtTime needs only one argument')
diff --git a/test/__init__.py b/test/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/test/test_arttime.py b/test/test_arttime.py
new file mode 100644
index 0000000..937be68
--- /dev/null
+++ b/test/test_arttime.py
@@ -0,0 +1,92 @@
+#!/usr/bin/env python3
+
+from datetime import datetime
+from arttools import arttime
+from astropy.time import Time
+from arttools.arttime import TZ_UTC
+from arttools.arttime import TZ_MSK
+import os
+import sys
+import unittest
+
+
+class TestConvertArtday(unittest.TestCase):
+
+    def setUp(self):
+        self._test_conv = {'artday': 8000., 'missiontime': 691200000., 'mjd': 59543.875, 
+        'datetime_msk': '2021-11-26T00:00:00', 'datetime_utc': '2021-11-25T21:00:00'}
+        self._test_mjd       = Time(self._test_conv['mjd'], format='mjd')
+        self._test_dtime_utc = datetime.fromisoformat(self._test_conv['datetime_utc']).replace(tzinfo=TZ_UTC)
+        self._test_dtime_msk = datetime.fromisoformat(self._test_conv['datetime_msk']).replace(tzinfo=TZ_MSK)
+
+    def test_ArtTime_mjd(self):
+        mjd = arttime.ArtTime(mjd=self._test_conv['mjd'])
+        self.assertEqual(mjd.mjd.time, self._test_mjd)
+
+    def test_mjd_convert(self):
+        mjd            = arttime.ArtTime(mjd=self._test_conv['mjd'])
+        test_dtime_utc = datetime.fromisoformat(self._test_conv['datetime_utc']).replace(tzinfo=TZ_UTC)
+        test_dtime_msk = datetime.fromisoformat(self._test_conv['datetime_msk']).replace(tzinfo=TZ_MSK)
+        self.assertEqual(mjd.artday.time, self._test_conv['artday'])
+        self.assertEqual(mjd.missiontime.time, self._test_conv['missiontime'])
+        self.assertEqual(mjd.datetime_utc.time, test_dtime_utc)
+        self.assertEqual(mjd.datetime_msk.time, test_dtime_msk)
+
+    def test_ArtTime_artday(self):
+        artday = arttime.ArtTime(artday=self._test_conv['artday'])
+        self.assertEqual(artday.artday.time, self._test_conv['artday'])
+
+    def test_artday_convert(self):
+        artday = arttime.ArtTime(artday=self._test_conv['artday'])
+        self.assertEqual(artday.mjd.time, self._test_mjd)
+        self.assertEqual(artday.missiontime.time, self._test_conv['missiontime'])
+        self.assertEqual(artday.datetime_utc.time, self._test_dtime_utc)
+        self.assertEqual(artday.datetime_msk.time, self._test_dtime_msk)
+
+    def test_ArtTime_missiontime(self):
+        missiontime = arttime.ArtTime(missiontime=self._test_conv['missiontime'])
+        self.assertEqual(missiontime.missiontime.time, self._test_conv['missiontime'])
+
+    def test_cyclic_conversion_missiontime(self):
+        missiontime       = arttime.ArtTime(missiontime=self._test_conv['missiontime'])
+        datetime_utc      = str(missiontime.datetime_utc)
+        test_datetime_utc = arttime.ArtTime(datetime_utc=datetime_utc)
+        self.assertEqual(missiontime.missiontime.time, test_datetime_utc.missiontime.time)
+
+    def test_missiontime_convert(self):
+        missiontime = arttime.ArtTime(missiontime=self._test_conv['missiontime'])
+        self.assertEqual(missiontime.mjd.time, self._test_mjd)
+        self.assertEqual(missiontime.artday.time, self._test_conv['artday'])
+        self.assertEqual(missiontime.datetime_utc.time, self._test_dtime_utc)
+        self.assertEqual(missiontime.datetime_msk.time, self._test_dtime_msk)
+
+    def test_ArtTime_datetime_utc(self):
+        datetime_utc = arttime.ArtTime(datetime_utc=self._test_conv['datetime_utc'])
+        self.assertEqual(datetime_utc.datetime_utc.time, self._test_dtime_utc)
+
+    def test_datetime_utc_convert(self):
+        datetime_utc = arttime.ArtTime(datetime_utc=self._test_conv['datetime_utc'])
+        self.assertEqual(datetime_utc.mjd.time, self._test_mjd)
+        self.assertEqual(datetime_utc.artday.time, self._test_conv['artday'])
+        self.assertEqual(datetime_utc.missiontime.time, self._test_conv['missiontime'])
+        self.assertEqual(datetime_utc.datetime_msk.time, self._test_dtime_msk)
+
+    def test_ArtTime_datetime_msk(self):
+        datetime_msk = arttime.ArtTime(datetime_msk=self._test_conv['datetime_msk'])
+        self.assertEqual(datetime_msk.datetime_msk.time, self._test_dtime_msk)
+
+    def test_datetime_msk_convert(self):
+        datetime_msk = arttime.ArtTime(datetime_msk=self._test_conv['datetime_msk'])
+        self.assertEqual(datetime_msk.mjd.time, self._test_mjd)
+        self.assertEqual(datetime_msk.artday.time, self._test_conv['artday'])
+        self.assertEqual(datetime_msk.missiontime.time, self._test_conv['missiontime'])
+        self.assertEqual(datetime_msk.datetime_utc.time, self._test_dtime_utc)
+
+    def test_ArtTime(self):
+        datetime_utcnow      = arttime.ArtTime()
+        test_datetime_utcnow = datetime.utcnow().replace(tzinfo=TZ_UTC)
+        self.assertLess((test_datetime_utcnow - datetime_utcnow.datetime_utc.time).total_seconds(), 60.)
+
+
+if __name__ == "__main__":
+  unittest.main()
\ No newline at end of file