How can I scroll vertically the ConstraintLayout?

To add scrolling to any view, you add a ScrollView. In your code, add it as the root(If the ScrolLView isn't the root and there is more content, add the ScrollView around the ConstraintLayout). move the namespaces(lines containing xmlns) to the new root. Add width and height in the ScrollView to match_parent(or whatever you have) and set the height of the ConstraintLayout to wrap_content.

However, you will not be able to scroll correctly in design mode. (reference). But it will still work as ecpected on a device.

NOTE:

If your layout doesn't scroll with a SCrollView, make sure you set the height of the ConstraintLayout to wrap_content

For making the elements in the screen scrollable I think you could use a NestedScrollView inside a CoordinatorLayout. I usually put a LinearLayout with all the elements I would display there.

For example:

<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.xengar.android.puzzlewildanimals.ui.HelpActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            android:background="?attr/colorPrimary"
            app:popupTheme="@style/ThemeOverlay.AppCompat.Dark" />

    </android.support.design.widget.AppBarLayout>

    <android.support.v4.widget.NestedScrollView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_behavior="@string/appbar_scrolling_view_behavior">

        <android.support.constraint.ConstraintLayout  
        xmlns:android="http://schemas.android.com/apk/res/android"
        xmlns:app="http://schemas.android.com/apk/res-auto"
        xmlns:tools="http://schemas.android.com/tools"
            android:id="@+id/desciptionScroll"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            tools:context="com.picture.nasa.nasadailyimage.NasaDailyImage"
            tools:showIn="@layout/activity_nasa_daily_image">


            <TextView
                android:id="@+id/imageTitle"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="8dp"
                android:layout_marginStart="8dp"
                android:text="@string/test_image_title"
                app:layout_constraintLeft_toLeftOf="parent"
                app:layout_constraintTop_toTopOf="parent" />

            <TextView
                android:id="@+id/imageDate"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="8dp"
                android:layout_marginStart="8dp"
                android:text="@string/test_image_date"
                app:layout_constraintLeft_toLeftOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/imageTitle" />

            <ImageView
                android:id="@+id/imageDisplay"
                android:layout_width="368dp"
                android:layout_height="408dp"
                android:layout_marginLeft="8dp"
                android:layout_marginStart="8dp"
                android:layout_marginTop="3dp"
                android:src="@mipmap/test_image"
                app:layout_constraintLeft_toLeftOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/imageDate" />

            <TextView
                android:id="@+id/imageDescription"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="8dp"
                android:layout_marginStart="8dp"
                android:layout_marginTop="4dp"
                android:text="@string/test_image_description"
                app:layout_constraintLeft_toLeftOf="parent"
                app:layout_constraintTop_toBottomOf="@+id/imageDisplay" />




        </android.support.constraint.ConstraintLayout>
    </android.support.v4.widget.NestedScrollView>

</android.support.design.widget.CoordinatorLayout>

If that doesn't work you can replace the ConstraintLayout with a LinearLayout. I hope that helps.