How It All Began: “To Infinity and Beyond”

Orion Nebula

From Nebulae to Stars to Galaxies and Beyond!

“TO INFINITY AND BEYOND”

Mysteries galaxies cover,

Restlessness stars show,

Beauty planets exhibit,

In the infinity and beyond!

From minuscule neutrinos to the expanding Universe, astronomy rules the Fabric of the Cosmos. But in my birthplace, the sky is hidden by a mask of light pollution and fossil fuel wastes. I often pondered what lay above those hazy clouds. After emigrating from Shenyang, I saw for the first time a sky clearer than water and stars brighter than Zeus’ bolt. Thus began my fascination with astronomy. And like the constellations of the zodiac that appear in certain months, I had occasional close encounters with astronomy. There was a lesson in a 6th grade outdoor education class and a telescope viewing session in Pasadena. I even took an astronomy course at the community college. All of these transient, astronomical sparks ultimately culminated in my unforgettable COSMOS experience. My high school barely covers astronomy, so I rely on my home telescope, where all I can see is the moon, Jupiter, and Saturn. But in a university setting, I discovered and utilized the infinite, incredible resources for research and learning.

As the sun sank beneath the golden horizon, I waited patiently for the TAs to finish calibrating the 24-inch telescope inside the UCI observatory dome. After Dr. Smecker-Hane explained how to use a sky map, I mastered the technique and shouted out constellations: “Orion! Big Dipper!” Inside the observatory dome, I ascended the creaky steel ladder and gazed into the telescope’s eyepiece, seeing one area concentrated with stars, the open cluster M11. Though light years away, M11 seemed so impossibly close that I could reach up and snatch its stars out of the sky, as though I was a scientist observing stars on an ebony Petri dish through a microscope. On the 8-inch telescope, Mars shone like ancient blood-stained battlefields, while Saturn’s ice rings revolved as magnificently as clockwork.

The professors enlightened me with intriguing astronomy stories, such as the irony of Einstein’s obstinacy. Though he rejected Friedmann’s theory of an expanding universe, Einstein’s cosmological constant, when reversed, actually supports the theory of Universe acceleration. The program’s CLEA1 exercises prepared me for group projects as I learned some of the math behind astronomy― calculating the mass of Jupiter using its moons’ orbits and “blinking” to determine asteroids’ velocities. In one CLEA simulation, I found not galaxies, but portraits of scientists floating in space instead! For my group research project, “Stellar Spectra,” we observed the night sky, recorded images of Arcturus and Vega, reduced them with Linux software, and designed a poster board decorated with colored dots depicting the stars of the H-R Diagram. We presented our “findings” to parents, students, and professors at a science fair convention. During this research process, I imagined myself as the modern Galileo voyaging through territory few had traversed.

COSMOS was the launch pad in expanding my astronomy blog, coincidentally named “The Cosmos.”I blog actively, and have discovered kindred spirits with minds eager to learn, inquire, and comment. Originating globally across six continents in countries like Germany and India, the feedback I receive increases my fascination. COSMOS confirmed my desire to study astronomy, conduct research, and become a part of the scientific community. Astronomy is the oldest science, yet each discovery raises more questions. In every astronomical encounter I travel on an unforgettable journey invoked by imagination.

1 CLEA is an acronym for Contemporary Lab Experiences in Astronomy.

~ Tianjia Liu, 2012 ~

Advertisements

Supernovae: Dying Stars

Star Death

Lifetime of a Star

It is true that all living things come from stardust. In about 5 billion years, our Sun will have swelled to a red giant and engulfed the inner planets, ready to explode in a supernova. Supernovae enrich the interstellar medium with high mass elements, like iron and calcium. The high energy from supernovae also triggers formation of new stars. On average, supernovae occur only about once every 50 years in the Milky Way Galaxy. They are rare events— so rare that the last one in the Milky Way was discovered in 1604 (SN 1604, or Kepler’s Supernova)— spectacularly luminous and extremely destructive. In fact, supernovae can cause bursts of radiation more luminous than entire galaxies and emit as much energy as the Sun will in its entire lifespan! In a supernova, most of the star’s material is expelled into space at speeds up to 30,000 m/s. The shock wave passes through the supernova remnant, a huge expanding shell of gas and dust. Supernova are caused either by the sudden gravitational collapse of a supergiant star (Type I Supernova) or a white dwarf accreting enough mass or merging with a binary companion to undergo nuclear fusion (Type II Supernova). White dwarfs are very dense stars that do not have enough mass to become a neutron star (formed from supernova remnant, stars comprising almost entirely of neutrons). Supernovae can be used as standard candles (objects with known luminosity). For instance, the dimming luminosity of distant supernovae supports the theory that the expansion of the universe is accelerating. Now, with powerful telescopes like Hubble, many supernovae are discovered each year. How perfectly supernovae represent the circle of life: from death comes life!

History of Supernova Observations (Milky Way)

  • SN185 by Chinese astronomers
  • SN1006 by Chinese and Islamic astronomers
  • SN1054 (caused Crab Nebula)
  • SN1572 by Tycho Brahe in Cassiopeia
  • SN1604 by Johannes Kepler

* Supernova (SN) are named by the year they are discovered; if more than one in one year, the name is followed by a capital letter (A, B, C, etc.), and if more than 26, lowercase paired letters (aa, ab, etc.) are used

Below is a video on supernovae! Enjoy.

Fun Facts Cluster 2: From Space Rocks to Drones (AskAstro)

1. SPACE ROCK SUICIDE: Scientists can detect a comet or asteroid colliding into the Sun’s surface. The self-destructing comet or asteroid will explode due to pressure of traveling into the Sun’s photosphere. The brightness and impact of the collision depends on the mass of the object. A collision as such is high unlikely, however, because: 1) most comets and asteroids would to dust and vapor in the sizzling atmosphere of the Sun 2) objects will lose most of its mass as they approach the Sun 3) objects normally orbit the Sun, so the objects’ orbit must be altered or the object may be from another planetary system.

2. STELLAR DONATIONS: In a binary star system, if stars are close enough, tides can become so strong that the more gravitationally strong star call pull gas from the surface of its companion. Though the “tidal transfer” depends on the mass of the donor star, if two stars have equal mass, the accretor (the star gaining mass) will steal mass if the donor star’s radius exceeds 38 percent of the binary separation (distance between the stars) no matter the separation.

3. COLOR CODE: The dark and light horizontal bands depend on the organization of winds in Jupiter’s atmosphere. The light bands have a eastward jet on the side closest to the pole, and vice versa in the dark bands. The zones (light bands) appear bright because of colorless high-altitude clouds that contain ammonia ice. The belts (dark bands) have much thinner high altitude clouds and darker particles.

4. DANGEROUS FLYBY: NASA calculates the planetary flybys with nothing but Newton’s laws of motion. The desired closest approach depends on the mission and how much added velocity boost the mission requires.  The mass and closeness of the planet determines the bending of trajectory the probe must undergo. The approach distance can range from a few hundred to several thousand kilometers.

From: Astronomy magazine December 2012 Vol 41 Issue 12

The 8 Planets: A Series

The Solar System

When you look at the sky on a clear night, what do you see? Stars twinkling, constellations rising, or perhaps a cow jumping over the full Moon? We can clearly see stars light years away, yet through even a telescope stars are only pinpoints of light. But is every bright point of light a star?

Some of the bright pinpoints of lights we see are actually the planets of our solar system. While we may only see 1 or 2 planets with the naked eye, we may observe the distinct features of planets through a telescope. The reddish coloration of Mars. The rings of Saturn. Jupiter’s four biggest moons Io, Europa, Ganymede, and Callisto. But how can you tell whether they are planets or stars? Stars twinkle. Planets do not because they reflect sunlight. Most planets appear brighter than stars. Or… you could whip out your handy-dandy Google Sky Map app or any other sky map app!

That we are looking at the same sky our ancestors did over the last thousands of years is spectacular. Though pollution many have obscured some objects from our view, the sky has changed very little. From a dark area, we can still see what the hunter-gatherers saw!

To the observer, the local objects like the planets are intermixed among the infinite stars. But what mysteries are the eight planets hiding? How is each planet unique? How many moons does each planet have? What are their histories? I hope to explore the planets from every angle, for these planets are our home (Earth) and our neighbors (all planets except Earth). Eight posts in the near future will be dedicated to the eight planets. Each planet will be explained and unraveled. Let the journey through the solar system begin!

The Milky Way – Structure and Origin

The Milky Way and Its Magellanic Clouds

The Milky Way and Its Magellanic Clouds

In the Southern Hemisphere, the Magellanic Clouds, or the galaxy’s satellite galaxies (revolves around Milky Way), are visible. The Magellanic Clouds are named for the Portuguese explorer Ferdinand Magellan, the first circumnavigator of the world. Because of interstellar dust (rocky planets and other material), we can only see 6,000 stars, but the Milky Way has 100 billion stars total. The farthest are 4,000 light years away. Earth’s atmosphere smears the sky, so stars appear to twinkle. About 10^6 stars— old as the universe— inhabit In globular clusters (~200 in Milky Way’s halo).

All pictures of the Milky Way are artists’ conceptions because no telescope can travel high enough (billions of light years) to capture the entire galaxy.

Milky Way – Structure

Shapley’s Subdivision of the Milky Way

  1. Nuclear Bulge: (10^6 solar masses) nucleus in the center, old stars (red)
  2. The Disk: (10^11 solar masses) thin, diffuse layer of material revolving around the bulge; the Sun is half-way on the disk; all young stars
  3. The Halo: hot gas about 100,000 K
  4. Galactic Corona: mass exists but unseen; 5-10 times as much mass as the nucleus, disk, and halo together, 95% of galaxy mass unknown matter
  • Visible Matter: 96% stars, 4% interstellar gas

Origin

  1. (13.6 billion years ago) A gas cloud of 75% hydrogen and 25% helium with mass ~ 1 trillion solar masses
  2. Contraction and rotation form spherical shape
  3. Inner part flattens to form disk of younger stars
  4. Galactic rotation forms spiral arms
  5. Supernovae gives off more heavy elements that eventually become the Sun

COSMOS: UCI – Part 2

UCI Observatory

The UCI Observatory is located about a mile from the UCI campus. Though relatively small compared to famous observatories such as Keck Observatory in Hawaii or Kitt Peak Observatory in Arizona, the UCI Observatory serves basic viewing purposes. UCI Observatory dome houses a 24-inch telescope with a CCD camera and a 8-inch portable telescope. UCI professor Dr. Tammy Smecker-Hane and TAs Liuyi Pei, John Phillips, and Shea Garrison-Kimmel adjusted the telescopes and pointed them toward objects of interest, among which were the Ring Nebula, Mars, Saturn, star clusters, and a binary star system.

“As a bumpy, seat-wrangling dirt road emerges, a muddy, night-black SUV launches itself past ironclad gates. City lights twinkle to the left; hills lined with sharp grasses cast shadows to the right. Music blasts from speakers; Cosmonauts chatter nonstop, voices intermixed. A gray-white dome emerges and four shadows await, silently calibrating the 24 and 8-inch ocean-blue telescopes. As the sun dips beneath the horizon, night blankets the earth and icy air tackles my vest and slacks. First the moon, then Vega and Ursa Major— the true celestial sphere has appeared.” – Tianjia Liu

COSMOS: UCI – Part 1