Exoplanets, Nebulae, and Galaxies

Observatory / Course Archives / ASTR 110 Fall 2019 / Bailen

Exoplanet Wasp-12b

Discovered in 2008, Wasp-12b is an egg-shaped exoplanet located 1,200 light-years away in the constellation of Auriga; temperatures can reach as high as 4,000° F. This exoplanet was discovered via the transit method. Being classified as a "Hot Jupiter", Wasp-12b has a 1.1 day orbit around its star. Interestingly, it is orbiting so close to its parent star, that it is being torn apart. Wasp-12b was the first discovered carbon-rich planet, and has more carbon than oxygen in its atmosphere. A fun fact about this exoplanet is that concentrated carbon takes the form of diamond, and thus it is possible that there is an abundant amount of diamond in the exoplanet's interior.

The parents star's gravity strips the exoplanet and forms a disk around it; eventually, in 10 million years, the exoplanet will be consumed by the parent star. In addition to this, the gravity causes strong tidal forces, which consequently pulls the exoplanet into its egg shape. During an event known as a "secondary eclipse", NASA's Spitzer Telescope indicated the presence of molecules as the planet orbited behind its star. Through a calculation of the emission of infrared light, the planet could be observed at different wavelengths of infrared light.

Nebula NBC 7293, The Helix Nebula

The Helix Nebula, being about 10,600 years old, is located in the constellation Aquarius. The planetary nebula is also known as the "Eye of God" and the "Eye of Sauron" because of its appearance. The Helix Nebula is one of the largest planetaries known - 16 arc minutes in diameter - , and is also one of the closest planetary nebula. Nebulae are simply the remains of stars after they have died. In addition to this, the Nebula is one of the first planetary nebulae discovered to have cometary knots; it is believed to contain about 20,000 cometary knots.

Each individual knot has bright cusps and tails, and they extend away from the central star in a radial direction. Interestingly, the Helix Nebula is the only known planetarynebila for which a parallax can be obtained via ground-based observations. Despite having noticeable differences in its appearance, the Helix Nebula is unique in that it appears similar across a wide spectrum, from ultraviolet to infrared, and is thus easy to recognize at all these different wavelengths. The Helix Nebula's inner disk is at a rate of 32 kilometers per second, and the outer ring has an expansion rate of 40 kilometers per second.

Galaxy Messier 64

Galaxy Messier 64 is a spiral galaxy located 24 million lightyears away from Earth in the Constellation Coma Berenices. This galaxy is also known as the "Black Eye Galaxy" because of the enormous light-absorbing dust band in front of its central region; this dust band hides stars found in the galaxy's bright core. Messier 64 finds company in a small group of galaxies known as the M94 Group, or the Canes Venatici I Cloud (CVn I Cloud). In 1779, the galaxy was discovered by Edward Pigott, and independently found 12 days later by Johann Elert Bode. M64 has two counter-rotating disks, which are roughly equal in mass; the inenr disk where the galaxy's dust clouds and lanes can be found. Interestingly, although all the stars rotate clockwise - the same as the gas in thecore region - the gas in the outer regions rotate counter-clockwise.

The Black Eye Galaxy also has intense starburst activity. This may be explained by the inner zone rubbing along the outer disk, but rotating in opposite directions. Although it is not fact, the counter-rotating system may have formed as a consequence of collision that occured approximately a billion years ago that led a to a merger with a smaller, gas-rich galaxy with a retrograde orbit.