Light Detectives Using NASAs WISE Data to Identify

Light Detectives Using NASA’s WISE Data to Identify Brown Dwarfs and ULIRGs Light Detectives

Brown dwarfs Limb of Sun Brown dwarf Very low mass star Light Detectives – #2 Brown dwarf Jupiter

Where is the brown dwarf? Light Detectives – #3

How do astronomers know what they know? COLO W 1 = 3. 4 microns W 2 = 4. 6 microns W 3 = 12 microns 2 Regular Stars Brown Dwarfs Light Detectives – #4 (more green [W 2], less blue [W 1])

Where is the brown dwarf? Light Detectives – #5

Light Detectives – #6

Let’s find a brown dwarf more scientifically using real NASA data The Process: 1. Find and download the data 2. Make measurements 3. Plot and interpret the results Light Detectives – #7

• A finder chart shows you where to find objects in the sky. • The same objects will appear in each of the WISE images you download. Light Detectives – #8

How do astronomers know what they know? COLO W 1 = 3. 4 microns W 2 = 4. 6 microns W 3 = 12 microns 2 Regular Stars Brown Dwarfs Light Detectives – #9 (more green [W 2], less blue [W 1])

Sample color-color diagram for brown dwarf search W 2/W 1 vs W 3/W 2 0. 8 6 0. 7 1 2 2 0. 6 3 W 2/W 1 4 5 9 0. 5 6 38 0. 4 11 12 7 5 1 4 8 10 9 7 10 11 0. 3 12 0. 05 0. 1 Light Detectives – #10 0. 15 0. 2 W 3/W 2 0. 25 0. 35

Color-Color Diagram 5 • Brown dwarfs have LOW intensity in W 1. AGB Stars 4 • Brown dwarfs are relatively BRIGHT in W 2 light. W 2/W 1 3 • What objects have high W 2/W 1 ratios? Brown Dwarfs 2 ULIRGs • What objects have higher W 3/W 2 ratios than brown dwarfs? 1 Stars Normal Galaxies 0 0 1 2 3 4 5 W 3/W 2 Light Detectives – #11 6 7 8 9

ULIRGs Ultra-Luminous Infrared Galaxies Light Detectives – #12

Arp 220 Light Detectives – #13

• A finder chart shows you where to find objects in the sky. • The same objects will appear in each of the WISE images you download. Light Detectives – #14

Sample color-color diagram for ULIRG search W 2/W 1 vs W 3/W 2 1 11 2 1. 0 3 4 W 2/W 1 0. 8 5 6 0. 6 7 0. 4 27 3 10 84 61 12 59 8 9 10 0. 2 11 0. 0 1. 0 Light Detectives – #15 2. 0 3. 0 W 3/W 2 4. 0 5. 0 6. 0 12

WISE color image Light Detectives – #16

WISE color image Hubble image ULIRG created by two merging galaxies! Light Detectives – #17