NASA

by Lance D. Davis Did you know our planet has two types of seasons? They are meteorological and astronomical. What’s the difference? “Meteorological seasons” follow the changing of the calendar, month to month, and are based on the annual temperature cycle – seasonal temperature variations modified by fluctuations in the amount of solar radiation received by Earth’s surface over the course of a year. For instance, the meteorological season of spring begins each year on March 1 and will end on May 31. However, “astronomical” seasons happen because of the tilt of Earth’s axis (with respect to the Sun-Earth plane), and our planet’s position during its orbit around the Sun. An illustration of the March (spring) and September (fall or autumn) equinoxes. During the equinoxes, both hemispheres...

Nearly 100 years ago, astronomer Bernard Lyot invented the coronagraph – a device that made it possible to recreate a total solar eclipse by blocking the Sun’s light. That helped scientists study the Sun’s corona, which is the outermost part of our star’s atmosphere that’s usually hidden by bright light from its surface.Our Nancy Grace Roman Space Telescope, now under construction, will test out a much more advanced version of the same thing. Roman’s Coronagraph Instrument will use special masks to block the glare from host stars but allow the light from dimmer, orbiting planets to filter through. It will also have self-flexing mirrors that will measure and subtract starlight automatically.This glare-blocking prowess is important because planets can be billions of times dimmer than their h...

BETHESDA, Md. — The U.S. government’s support for the commercial remote sensing satellite industry is at a critical juncture amid growing military demand for real-time intelligence, industry experts said Aug. 27.  The commercial remote sensing satellite industry is expanding, but it’s still not equipped to meet evolving U.S. military needs for tactical intelligence, surveillance and reconnaissance (ISR), said David Gauthier, former head of commercial operations at the National Geospatial-Intelligence Agency (NGA). Tactical ISR refers to the immediate collection and analysis of data to inform military operations on the battlefield. This intelligence is crucial for decision making during to dynamic situations.  Speaking at the AFCEA-INSA Intelligence and National Security S...

Later this month, a SpaceX Falcon Heavy rocket will take to the skies for the third time to launch the Department of Defense’s Space Test Program-2 (STP-2) mission. Several exciting, one-of-a-kind NASA technology and science payloads are among the two-dozen spacecraft aboard.First, let’s talk about that Falcon Heavy rocket. Its 27 engines generate thrust at liftoff equal to that of approximately 18 airplanes, and it can lift over 140,000 pounds. Managed by the U.S. Air Force Space and Missile Systems Center, STP-2 is the first government-contracted Falcon Heavy launch. It will reuse the two side boosters recovered after the April flight. SpaceX describes it as one of the most challenging launches in the company’s history. It’s a big deal to us at NASA because we’re launching some pretty co...