A Spring Constellation - Longmont Astronomical … · A Spring Constellation . LEO CONSTELLATION • 12th largest constellation in size ... Garzone Photos by Gary Garzone Leo Triplet

LEO THE LION

A Spring Constellation

LEO CONSTELLATION

• 12th largest constellation in size

• One of the zodiac constellations – sun passes through : Aug 10th to Sep 16th

• Contains five Messier objects and 11 stars with known planets

• Two meteor showers: Leonids – 17-18 Nov & Jan 1-7

Diagram Wikipedia

MYTHOLOGY

• One of oldest constellations, traced back 4,000 BC Mesopotamians

• Catalogued by the Greek astronomer Ptolemy in 2nd century

• Greeks depicted Leo as the Nemean Lion, killed by Hercules as the first of his twelve labors

LOCATING LEO

Messier Marathon Field Guide

MAJOR STARS IN LEO

Algieba (Gamma Leonis) – lion’s neck; double star visible in small scopes; 126 ly distant

Regulus (Alpha Leonis) – lion’s heart; brightest star in Leo and 22nd brightest in sky; composed of two pairs of stars; 77 ly distant Denebola - (Beta Leonis) - tip of the lion’s tail; 2nd

brightest star in Leo and 61st brightest in sky; relatively young star and fast rotator; strong infrared excess suggests circumstellar disc of dust in orbit

Zosma (Delta Leonis) – lion’s rump; white main sequence star; rapid rotator

NightWatch

MESSIER OBJECTS IN LEO

M65 (NGC 3623) – intermediate spiral galaxy; 35 million ly distant most stars are old

M66 (NGC 3627) – intermediate spiral galaxy; 36 million ly distant; notable for dust lanes and bright star clusters

M65-M66-NGC 3628 by Gary Garzone

Photos by Gary Garzone

Leo Triplet

MESSIER OBJECTS IN LEO

M95 (NGC 3351) – barred spiral galaxy; 38 million ly distant; ringshaped starburst region around the core

M96 (NGC 3368) – intermediate spiral galaxy; 31 million ly distant; Double-barred spiral with small inner bulge

M105 (NGC 3379) – elliptical galaxy; 32 million ly distant; known to have a supermassive black hole at its center

Brian Kimball photo

NASA/ESA

ESO

ALSO WORTH VIEWING

From Bob Stohl’s series of talks on Messier objects M44 photo by Brian Kimball

TAKE A LOOK AT LEO

• Easy to find zodiac constellation

• Great mythological story

• Contains five Messier objects and multiple interesting stars

• Easy star hop to Cancer, Gemini, Auriga

• Two meteor showers: Leonids – 17-18 Nov & Jan 1-7