NGC 6302

Look at the Butterfly Nebula.

It looks like big wings. A ring of dust sits in the middle. This ring makes the gas flow out in two directions. It looks like an hourglass.

A very hot star lives in the center. This star is one of the hottest known. It is hard to see because of the dust. A big telescope found it in 2009. This star was once much larger. Now it is a small, fading star. It is a beautiful sight in the sky.

Look at the Butterfly Nebula.

It sits in the Scorpius constellation. This object has a very complex shape. Some people call it the Bug Nebula.

In the middle, a thick ring of gas and dust sits. This ring is called an equatorial disc. This disc helps shape the gas. It makes the gas flow out in two directions. This creates a shape like an hourglass.

One part of the nebula is a large lobe. It likely formed from a big event 1,900 years ago. The gas in this part moves very fast. At the very edge, it moves over 600 km/s.

A very hot star lives in the center. It is a white dwarf, which is a small, fading star. This star is one of the hottest known. Its surface is over 250,000 degrees Celsius. The star has a mass of 0.64 solar masses. This means it is 0.64 times the mass of our Sun.

People found the star in 2009. They used the Hubble Space Telescope to see it. The dust in the ring makes the star hard to find.

The Butterfly Nebula is a beautiful and strange object in the sky. It sits in the constellation Scorpius. Some people also call it the Bug Nebula or Caldwell 69. This object is a bipolar planetary nebula. This means it has two main lobes that look like wings.

It has one of the most complex shapes ever seen in such a nebula. The nebula is very large and full of gas and dust. It is a wonderful thing to study from Earth.

A thick ring of gas and dust sits in the center. This is called a dense equatorial disc. This disc acts like a wall for the star. It forces the gas to flow out in two directions. This creates a shape that looks like an hourglass.

One large lobe in the northwest grew from an eruption 1,900 years ago. The gas there moves at very high speeds. At the outer edge, the speed is over 600 km/s. Some parts of the edge might have hit older clouds of gas.

People have been looking at this nebula for a long time. It has been in the New General Catalogue since at least 1888. Many people think James Dunlop discovered it in 1826.

Another scientist named Edward Emerson Barnard studied it in 1907. He drew pictures and wrote about what he saw. Later, the Hubble Space Telescope took very clear images of it. These images helped us see the nebula much better than before.

At the very center is a tiny, bright star. This star is a white dwarf. It was finally found in 2009 using the Hubble Space Telescope. The star is one of the hottest stars we know. Its surface temperature is over 250,000 degrees Celsius.

The star has a mass of 0.64 solar masses. This means it is a fraction of the mass of our Sun. It was once a much larger star. It likely began as a B type main sequence star.

The dust in the center ring is very special. It contains things like water ice and quartz. Scientists also found carbon-bearing molecules there.

Usually, stars are either rich in oxygen or rich in carbon. This nebula has both types of molecules together. This makes it a very rare and interesting place. It shows us how stars change as they get older. We can learn a lot about space by looking at these tiny details.

NGC 6302 is a spectacular planetary nebula located in the constellation Scorpius. It is known by several names, including the Butterfly Nebula, the Bug Nebula, and Caldwell 69. This object is classified as a bipolar planetary nebula. This means its structure features two primary lobes that extend from a central point. The shape is remarkably complex, representing some of the most intricate structures ever seen in such nebulae.

The nebula's unique shape is created by a specific physical mechanism. A dense equatorial disc, made of gas and dust, surrounds the central star. This disc acts as a barrier at the star's equator. When the star releases outflows of material, the disc forces the gas to escape through the poles instead. This process results in a bipolar structure that resembles an hourglass. The lobes contain various features, including ionization walls, knots, and sharp edges.

One specific part of the nebula is the prominent northwest lobe. This lobe extends up to 3.0 arcminutes away from the central star. Scientists estimate this structure formed during an eruptive event roughly 1,900 years ago. The lobe has a circular section with expanding walls. In this area, the speed of the expansion is proportional to the distance from the star. At an angular distance of 1.71 arcminutes, the flow velocity is 263 km/s. At the very edge of the lobe, the outward velocity exceeds 600 km/s. The western edge suggests the outflow collided with existing globules of gas.

The history of observing NGC 6302 spans many decades. It has been part of the New General Catalogue since at least 1888. Many sources credit its discovery to James Dunlop in 1826. However, some researchers argue that Barnard may have mistakenly credited Dunlop. The earliest known detailed study was conducted by Edward Emerson Barnard in 1907. He provided drawings and descriptions of the object. More recently, the Hubble Space Telescope provided groundbreaking images after its final servicing mission in September 2009.

At the heart of the nebula lies a central star that was difficult to find. It remained hidden for a long time due to its high temperature and the surrounding dust. The star radiates mostly in the ultraviolet spectrum. Additionally, the dusty torus, or ring, absorbs much of the light from the central region. It was not until 2009 that the Wide Field Camera 3 on the Hubble Space Telescope revealed the star. This central star is a white dwarf. It has a current mass of approximately 0.64 solar masses.

This white dwarf is one of the hottest known stars in the universe. Its surface temperature is in excess of 250,000 degrees Celsius. This extreme heat implies the original star was very large. In its earlier life, the star was likely a B type main sequence star, specifically a B5-9V. That original star had a mass of around five solar masses. Most of that mass was ejected during the event that created the nebula. Currently, the star has ceased nuclear burning. It is now fading at a predicted rate of 1% per year.

The chemistry of the dust in the central dark lane is quite unusual. It contains multiple crystalline silicates, crystalline water ice, and quartz. There is also evidence of carbon-bearing polycyclic aromatic hydrocarbons, also known as PAHs. Scientists have also debated the detection of carbonates in this non-aqueous environment. Usually, stars are either oxygen-rich or carbon-rich. This change typically happens late in a star's life due to chemical changes in its atmosphere. NGC 6302 is unique because it contains both oxygen-bearing silicate molecules and carbon-bearing molecules. This makes it a vital subject for studying how stars evolve and change their chemical makeup.