Download ESSAY - First Earth-Like Exoplanet Found in Habitable Zone

ESSAY - First Earth-Like Exoplanet Found in Habitable Zone
Directions: You are to write a 5 paragraph essay on the two articles about a newly discovered
exoplanet. Answer the questions below in your essay. Read both articles and highlight
information related to the questions - this will help you in forming your essay. Only use the
information within these two articles for your essay. Your essay should take the following form:
• Introductory paragraph - should include a general statement of what the short essay is
about and information about the mission that discovered the exoplanet.
• Three body paragraphs - include information about the star system and planet and
what the importance of the information is.
• One conclusion paragraph that uses the information you wrote in your body that sums
up the importance of the information and what you feel the implications it may have.
You are to use a word processor to type up the essay - no hand written essays, so be sure to use
proper grammar, spelling, capitalization, punctuation, etc.. The foundation of your essay should
answer the following questions:
1. What is the name of the mission/spacecraft that has discovered this important
exoplanet.
2. Describe how the mission detects these exoplanets.
3. What is the name of the star system and planet.
4. How far away is the star system from our solar system
5. What the term “habitable zone” means and why it’s important to this exoplanet.
6. Compare the star this exoplanet is orbiting to our Sun:
a. Class
b. Size
c. Temperature
d. Luminosity (brightness)
7. Compare the exoplanet to the Earth
a. Distance from its star
b. Revolution period
c. Temperature
d. Size
8. How many exoplanets have been confirmed discovered by this mission that lie within
the ‘habitable zone”.
9. Why the existence of life is thought to be possible on other worlds.
5 points
8 points
11 points
Poor/needs improvement –
Adequate – essay somewhat
Excellent – essay easily
Organization
essay difficult to follow,
easily followed, basic
followed, effective transitions
no/inadequate transitions,
transitions used, has a
used, has introduction, body
rambling format
structured format
and conclusion
Adequate – fairly easy to
Excellent – essay is clear, to
Mechanics/Grammar Poor/needs improvement –
the point, no
sentences and paragraphs are read, few
difficult to read and
spelling/punctuation/grammar spelling/punctuation/grammar
errors
understand, numerous
errors
spelling/punctuation/grammar
errors
Excellent – answered all
Adequate – answered
Poor/needs improvement –
Completeness
questions, but left out details, questions completely and
did not all answer questions,
most information answered
questions answered with
correctly, information came
incorrect information, did not correctly, answers used
from article.
information from article
use information from the
article to answer questions
First Habitable-Zone Super-Earth Discovered in Orbit Around
a Sun-Like Star
http://www.sciencedaily.com/releases/2011/12/111205140525.htm
This diagram compares our own solar system to Kepler-22, a star system containing the first "habitable
zone" planet discovered by NASA's Kepler mission. (Credit: NASA/Ames/JPL-Caltech
ScienceDaily (Dec. 5, 2011) — NASA's Kepler Mission has discovered the first super-Earth
orbiting in the habitable zone of a star similar to the Sun. A team of researchers, including
Carnegie's Alan Boss, has discovered what could be a large, rocky planet with a surface
temperature of about 22 degrees Celsius (72 degrees Fahrenheit), comparable to a comfortable
spring day on Earth.
This landmark finding will be published in The Astrophysical Journal.
The discovery team, led by William Borucki of the NASA Ames Research Center, used
photometric data from the NASA Kepler space telescope, which monitors the brightness of
155,000 stars. Earth-size planets whose orbital planes are aligned such that they periodically pass
in front of their stars result in tiny dimmings of their host star's light--dimmings that can only be
measured by a highly specialized space telescope like Kepler.
This discovery is the first detection of a possibly habitable world in orbit around a Sun-like star.
The host star lies about 600 light-years away from us toward the constellations of Lyra and
Cygnus. The star, a G5 star, has a mass and a radius only slightly smaller than that of our Sun, a
G2 star. As a result, the host star is about 25% less luminous than the Sun. The planet orbits the
G5 star with an orbital period of 290 days, compared to 365 days for Earth, at a distance about
15% closer to its star than Earth from the Sun. This results in the planet's balmy temperature. It
orbits in the middle of the star's habitable zone, where liquid water is expected to be able to exist
on the surface of the planet. Liquid water is necessary for life as we know it, and this new planet
might well be not only habitable, perhaps even inhabited.
Numerous large, massive gas giant planets have been detected previously in habitable-zone orbits
around solar-type stars, but gas giants are not thought to be capable of supporting life. This new
exoplanet is the smallest-radius planet discovered in the habitable zone of any star to date. It is
about 2.4 times larger than that of Earth, putting it in the class of exoplanets known as superEarths.
While the mass of this new planet is not known, it must be less than about 36 times that of Earth,
based on the absence of a measurable Doppler (radial velocity) wobble in the host star. The
masses of several other super-Earths have been measured with the Doppler technique and
determined to lie in the range of about 5 to 10 times that of Earth: Some appear to be rocky, while
others probably contain major fractions of ice and water. Either way, the new planet appears to be
habitable.
"This discovery supports the growing belief that we live in a universe crowded with life," Boss
said. "Kepler is on the verge of determining the actual abundance of habitable, Earth-like planets
in our galaxy."
NASA's Kepler Confirms Its First Planet In Habitable Zone
http://www.jpl.nasa.gov/news/news.cfm?release=2011-373
Closer to Finding an Earth This artist's conception illustrates Kepler-22b, a planet known to comfortably
circle in the habitable zone of a sun-like star. Image credit: NASA/Ames/JPL-Caltech
PASADENA, Calif. (December 05, 2011) -- NASA's Kepler mission has confirmed its first
planet in the "habitable zone," the region around a star where liquid water could exist on a
planet's surface. Kepler also has discovered more than 1,000 new planet candidates, nearly
doubling its previously known count. Ten of these candidates are near-Earth-size and orbit in the
habitable zone of their host star. Candidates require follow-up observations to verify they are
actual planets.
The newly confirmed planet, Kepler-22b, is the smallest yet found to orbit in the middle of the
habitable zone of a star similar to our sun. The planet is about 2.4 times the radius of Earth.
Scientists don't yet know if Kepler-22b has a predominantly rocky, gaseous or liquid
composition, but its discovery is a step closer to finding Earth-like planets.
Previous research hinted at the existence of near-Earth-size planets in habitable zones, but clear
confirmation proved elusive. Two other small planets orbiting stars smaller and cooler than our
sun recently were confirmed on the very edges of the habitable zone, with orbits more closely
resembling those of Venus and Mars.
"This is a major milestone on the road to finding Earth's twin," said Douglas Hudgins, Kepler
program scientist at NASA Headquarters in Washington. "Kepler's results continue to
demonstrate the importance of NASA's science missions, which aim to answer some of the
biggest questions about our place in the universe."
Kepler discovers planets and planet candidates by measuring dips in the brightness of more than
150,000 stars to search for planets that cross in front, or "transit," the stars. Kepler requires at
least three transits to verify a signal as a planet.
"Fortune smiled upon us with the detection of this planet," said William Borucki, Kepler principal
investigator at NASA Ames Research Center at Moffett Field, Calif., who led the team that
discovered Kepler-22b. "The first transit was captured just three days after we declared the
spacecraft operationally ready. We witnessed the defining third transit over the 2010 holiday
season."
The Kepler science team uses ground-based telescopes and NASA's Spitzer Space Telescope to
review observations on planet candidates the spacecraft finds. The star field that Kepler observes
in the constellations Cygnus and Lyra can only be seen from ground-based observatories in spring
through early fall. The data from these other observations help determine which candidates can be
validated as planets.
Kepler-22b is located 600 light-years away. While the planet is larger than Earth, its orbit of 290
days around a sun-like star resembles that of our world. The planet's host star belongs to the same
class as our sun, called G-type, although it is slightly smaller and cooler.
Of the 54 habitable zone planet candidates reported in February 2011, Kepler-22b is the first to be
confirmed. This milestone will be published in The Astrophysical Journal.
The Kepler team is hosting its inaugural science conference at Ames Dec. 5-9, announcing 1,094
new planet candidate discoveries. Since the last catalog was released in February, the number of
planet candidates identified by Kepler has increased by 89 percent and now totals 2,326. Of these,
207 are approximately Earth-size, 680 are super Earth-size, 1,181 are Neptune-size, 203 are
Jupiter-size and 55 are larger than Jupiter.
The findings, based on observations conducted May 2009 to September 2010, show a dramatic
increase in the numbers of smaller-size planet candidates.
Kepler observed many large planets in small orbits early in its mission, which were reflected in
the February data release. Having had more time to observe three transits of planets with longer
orbital periods, the new data suggest that planets one to four times the size of Earth may be
abundant in the galaxy.
The number of Earth-size, and super Earth-size candidates, has increased by more than 200 and
140 percent since February, respectively.
There are 48 planet candidates in their star's habitable zone. While this is a decrease from the 54
reported in February, the Kepler team has applied a stricter definition of what constitutes a
habitable zone in the new catalog, to account for the warming effect of atmospheres, which would
move the zone away from the star, out to longer orbital periods.
"The tremendous growth in the number of Earth-size candidates tells us that we're honing in on
the planets Kepler was designed to detect: those that are not only Earth-size, but also are
potentially habitable," said Natalie Batalha, Kepler deputy science team lead at San Jose State
University in San Jose, Calif. "The more data we collect, the keener our eye for finding the
smallest planets out at longer orbital periods."