A Reflection Nebula

Reflection Nebula in OrionNGC 1999 is a reflection nebula. A reflection nebula doesn’t emit light on its own. Much like fog around a lamp post, a reflection nebula shines because the light from an embedded source illuminates its dust. NGC 1999 lies close to the Orion Nebula in a region of our galaxy about 1,500 light-year away where new stars are being formed. NGC 1999 is lit by a bright, recently formed star, visible just left of center in this Hubble photo. the star’s white color is caused by its high surface temperature (about 10,000 °C, twice that of the Sun).

Image Credit: NASA

A Brilliant Noob

HD 97300A newly formed star lights up the surrounding gas and dust clouds like a streetlight in enveloping fog, creating reflection nebula IC 2631. The glowing region is the reflection nebula known as IC 2631. These nebulae are clouds of cosmic dust that reflect light from a nearby star into space. IC 2631 is the brightest nebula in the Chamaeleon Complex, a large region of such clouds with numerous newborn and still-forming protostars. The complex is around 500 light-years away in the southern constellation of Chameleon. IC 2631 is illuminated by one of the youngest, most massive, and brightest stars in its region. This neighborhood is full of star-making material which form dark nebulae such as the dark areas above and below IC 2631 in this picture. Dark nebulae are so densely filled with gas and dust that they block background starlight.

HD 97300 a T Tauri star, the youngest visible stage for relatively small stars.They have not yet started to fuse hydrogen into helium in their cores like normal main sequence stars but are just starting to glow by generating heat from gravitational contraction. As these stars mature, they will lose mass and shrink, but during their T Tauri phase, these stars have not yet contracted to the more modest size that they will maintain for billions of years as main sequence stars. Because these young stars already have surface temperatures similar to their main sequence phase and because T Tauri-phase objects are essentially jumbo versions of their later selves, they appear brighter in their oversized youth than they will as mature main sequence stars.

Image Credit: ESO

NGC 1999

Reflection Nebula in OrionNGC 1999 is a reflection nebula. A reflection nebula doesn’t emit light on its own. Much like fog around a lamp post, a reflection nebula shines because the light from an embedded source illuminates its dust. NGC 1999 lies close to the Orion Nebula in a region of our galaxy about 1,500 light-year away where new stars are being formed. NGC 1999 is lit by a bright, recently formed star, visible just left of center in this Hubble photo. the star’s white color is caused by its high surface temperature (about 10,000 °C, twice that of the Sun).

Image Credit: NASA

Toby Jug

TobyJugThis is the reflection nebula IC 2220 (aka the Toby Jug Nebula). It’s about 1200 light-years away in the southern constellation of Carina (The Ship’s Keel). It’s a cloud of gas and dust illuminated from within by a red giant star. The nebula was created by the star losing part of its mass to the surrounding space, forming a cloud of gas and dust as the matter cools. The dust consists of elements such as carbon and simple, heat-resistant compounds such as titanium dioxide and calcium oxide (lime) and, in the case of this nebula, silicon dioxide (silica) as the most likely compound reflecting the star’s light. IC 2220 is visible because the star’s light is reflected off the grains of dust.

Red giants are formed from stars that are approaching the final stages of their evolution. These stars have almost depleted their hydrogen, the fuel for the nuclear reactions that occur during most of the life of a star. This causes the atmosphere of the star to expand enormously. Red giants are powered by fusion reactions in a shell of helium outside a carbon-oxygen core, occasionally accompanied by a hydrogen shell closer to the star’s surface.

Image Credit: ESO Cosmic Gems Programme