Making the thumbnails in the backend Media section bigger

I don’t see any way of hooking into this. Following the lead of wp_get_attachment_image takes nowhere…

// wp-admin/includes/class-wp-media-list-table.php
// line 200

case 'icon':
    $attributes="class="column-icon media-icon"" . $style;
?>
    <td <?php echo $attributes ?>><?php
        if ( $thumb = wp_get_attachment_image( $post->ID, array( 80, 60 ), true ) ) {
            if ( $this->is_trash || ! $user_can_edit ) {
                echo $thumb;
            } else {
?>
            <a href="https://wordpress.stackexchange.com/questions/59182/<?php echo get_edit_post_link( $post->ID, true ); ?>" title="<?php echo esc_attr( sprintf( __( 'Edit &#8220;%s&#8221;' ), $att_title ) ); ?>">
                <?php echo $thumb; ?>
            </a>

<?php           }
        }

---

Inspecting the output we see that the image is being forcefully resized, so manipulating the DOM can be an alternative.

add_action( 'admin_head-upload.php', 'wpse_59182_bigger_media_thumbs' );

function wpse_59182_bigger_media_thumbs() 
{
    ?>
    <script type="text/javascript">
        jQuery(document).ready( function($) {
            $('.wp-list-table img').each(function(){
                $(this).removeAttr('width').css('max-width','100%');
                $(this).removeAttr('height').css('max-height','100%');
            });
            $('.column-icon').css('width', '130px');
        });     
    </script>
    <?php
}

edit by Question asker ( Tom ):

I applied the solution in this question, and these are the results: