Participants of the Park to Park Ride cycle through Joshua Tree National Park, April 29, 2017. The event, hosted by Natural Resources and Environmental Affairs, Joshua Tree National Park and the city of Twentynine Palms, Calif. took riders from Knott’s Sky Park through Joshua Tree National Park to Keys View and back as the final event of Earth Day celebrations in the month of April. (U.S. Marine Corps photo by Cpl. Dave Flores) - Participants of the Park to Park Ride cycle through Joshua Tree National Park, April 29, 2017. The event, hosted by Natural Resources and Environmental Affairs, Joshua Tree National Park and the city of Twentynine Palms, Calif. took riders from Knott’s Sky Park through Joshua Tree National Park to Keys View and back as the final event of Earth Day celebrations in the month of April. (U.S. Marine Corps photo by Cpl. Dave Flores)

Mark Miller, husband of Tina Miller, former deputy, Combat Center Performance and Innovation Office, addresses friends and family during a celebration of life at Valley Community Chapel in Yucca Valley, Calif., in honor of Tina, April 29, 2017. (U.S. Marine Corps photo by Cpl. Thomas Mudd) - Mark Miller, husband of Tina Miller, former deputy, Combat Center Performance and Innovation Office, addresses friends and family during a celebration of life at Valley Community Chapel in Yucca Valley, Calif., in honor of Tina, April 29, 2017. (U.S. Marine Corps photo by Cpl. Thomas Mudd)

Marines with Tactical Training Exercise Control Group stand at attention during an Australian and New Zealand Army Corps (ANZAC) Day celebration aboard Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., April 25, 2017. ANZAC Day recognizes the anniversary of the landing of Australian and New Zealand forces during the Battle of Gallipoli in World War I. (U.S. Marine Corps photo by Sgt. Connor Hancock) - Marines with Tactical Training Exercise Control Group stand at attention during an Australian and New Zealand Army Corps (ANZAC) Day celebration aboard Marine Corps Air Ground Combat Center, Twentynine Palms, Calif., April 25, 2017. ANZAC Day recognizes the anniversary of the landing of Australian and New Zealand forces during the Battle of Gallipoli in World War I. (U.S. Marine Corps photo by Sgt. Connor Hancock)