try this code :) copy into this page (http://www.w3schools.com/html/tryit.asp?filename=tryhtml_intro) and play with it, until you get what you want.
<!DOCTYPE html>
<html>
<body>
<img src="http://sohowww.nascom.nasa.gov/data/realtime/mdi_igr/1024/latest.jpg" width="200" height="200" alt="our sun">
<img src="http://sohowww.nascom.nasa.gov/data/realtime/eit_304/512/latest.jpg" width="150" height="150" alt="our sun">
<img src="http://sohowww.nascom.nasa.gov/data/realtime/eit_171/512/latest.jpg" width="200" height="200" alt="our sun">
<img src="http://sohowww.nascom.nasa.gov/data/realtime/eit_195/512/latest.jpg" width="150" height="150" alt="our sun">
</body>
</html>