Thread: Collision detection

Hello, I'm just casually working on this game. For some reason I can not get the collision to work 100% of the time. Ill post the main class. Just ask if you want to see the others.

I apologize for the lack of comments. I was really only working on this for myself.

 
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
 
import java.util.ArrayList;
 
import javax.swing.JPanel;
import javax.swing.Timer;
 
public class Board extends JPanel implements ActionListener{
 
	 private Timer timer;
	 private Spacecraft spaceCraft;
	 private Meteor meteor;
	 private Spaceman astronaut;
 
 
	 private boolean ingame;
	 private int B_WIDTH;
	 private int B_HEIGHT;
	 private int count = 0;
	 private int counta = 0;
	 private int lives = 5;
	 private int score = 0;
 
 
	public Board(){
		addKeyListener(new TAdapter());
        setFocusable(true);
        setBackground(Color.BLACK);
        setDoubleBuffered(true);
 
        B_WIDTH = 800;
        B_HEIGHT = 500;
 
        count = 0;  
        counta = 0;
        lives = 5;
        score = 0;
 
 
        spaceCraft = new Spacecraft();
        meteor = new Meteor();
        astronaut = new Spaceman();
 
        timer = new Timer(5,this);
        timer.start();
	}
 
	public void paint(Graphics g) {
        super.paint(g);
 
        Graphics2D g2d = (Graphics2D)g;
 
        g2d.drawImage(spaceCraft.getImage(), spaceCraft.getX(), spaceCraft.getY(), this);
        g2d.drawString(spaceCraft.getX() + "," + spaceCraft.getY(), spaceCraft.getX() + 10, spaceCraft.getY() - 10);
        g2d.drawOval(spaceCraft.getX(),  spaceCraft.getY(), 20, 20);
        Font k = new Font("Serif", Font.BOLD, 18);
        g2d.setFont(k);
        g2d.drawString("Lives: "+lives,(( B_WIDTH/2 ) + 50), 25);
        g2d.drawString("Score: "+score,(( B_WIDTH/2 ) - 50), 25);
 
        ArrayList ms = meteor.getMeteorArray();
        ArrayList as = astronaut.getAstronautArray();
 
        for (int i = 0; i < as.size(); i++ ) {
        	Spaceman a = (Spaceman) as.get(i);
        	g2d.drawImage(a.getImage(), a.getX(), a.getY(),this);
        }
 
        for (int i = 0; i < ms.size(); i++ ) {
            Meteor m = (Meteor) ms.get(i);
            g2d.drawImage(m.getImage(), m.getX(), m.getY(), this);
            g2d.drawOval(m.getX(),m.getY(),64,64);
        }
 
        Toolkit.getDefaultToolkit().sync();
        g.dispose();
    }
	public void actionPerformed(ActionEvent e) {
 
		 ArrayList ms = meteor.getMeteorArray();
		 ArrayList as = astronaut.getAstronautArray();
 
		 for(int f = 0; f < as.size(); f++){
			 Spaceman a = (Spaceman) as.get(f);
			 if (a.isVisible()){
				 a.move();
			 }
			 else as.remove(f);
		 }
		 counta++;
		 if(counta%250 == 0){
			 astronaut.addAstronaut(); 
		 }
		 if(counta >= 1000){
			 counta=0;
		 }	
 
		 for (int f = 0; f < ms.size(); f++) {
		     Meteor m = (Meteor) ms.get(f);
		     if (m.isVisible()){ 
		         m.move();
 
 
		     }
		     else ms.remove(f);
		 }
         collision();
 
 
		 count++;
		 if(count%40 == 0){
			 meteor.addMeteor();	
		 }
		 if(count >= 1000){
			 count=0;
		 }
 
		 spaceCraft.move();
		 repaint();  
	 }
	public void collision(){
 
		//This doesnt work 100%
		//Seems to only work on the top left for some reason
		ArrayList ms = meteor.getMeteorArray();
		for(int z = 0; z < ms.size(); z++){
			Meteor m = (Meteor) ms.get(z); 
			if( 10 >= (Math.sqrt((spaceCraft.getX() - m.getX()) * (spaceCraft.getX() - m.getX()) + (spaceCraft.getY() - m.getY()) * (spaceCraft.getY() - m.getY())  ))){
				lives--;
				delay(1000);
				reset();
			}
		}
	}
	public void delay (int ms)
	{
		try
		{
			// Stop thread for specified milliseconds in brackets
			Thread.sleep (ms);
		}
		catch (InterruptedException ex)
		{
			// Do nothing
		}
	}
	private void reset(){
		spaceCraft.reset();
 
	}
	private class TAdapter extends KeyAdapter {
 
	        public void keyReleased(KeyEvent e) {
	        	spaceCraft.keyReleased(e);
	        }
 
	        public void keyPressed(KeyEvent e) {
	        	spaceCraft.keyPressed(e);
	        }
	 }
}

--- Update ---

Both objects are circles and this should judge the distance between the two circles.
i assume my equation is wrong

That's too much code to wade through. Point to where in this code mass the collisions are (and sometimes aren't) being detected.

I can not get the collision to work 100% of the time.

...does not really explain what the problem or symptoms are. Are things passing through others, are they bouncing too early or too late? Are the angles wrong? The list could go on.. Try to explain better what the problem is and/or post a SSCCE