Course Website: Course Website



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Course Website:

  • Course Website:

    • http://blogs.umass.edu/astron101-tburbine/
  • Textbook:

    • Pathways to Astronomy (2nd Edition) by Stephen Schneider and Thomas Arny.
    • You also will need a calculator.


Mine

  • Mine

  • Tuesday, Thursday - 1:15-2:15pm

  • Lederle Graduate Research Tower C 632

  • Neil

  • Tuesday, Thursday - 11 am-noon

  • Lederle Graduate Research Tower B 619-O



We will use Spark

  • We will use Spark

  • https://spark.oit.umass.edu/webct/logonDisplay.dowebct

  • Homework will be due approximately twice a week



Astronomy Help Desk

  • Astronomy Help Desk

  • Mon-Thurs 7-9pm

  • Hasbrouck 205

  • The Observatory should be open on clear Thursdays

  • Students should check the observatory website at: http://www.astro.umass.edu/~orchardhill for updated information

  • There's a map to the observatory on the website.



Hard to make questions that everybody gets right:

  • Hard to make questions that everybody gets right:

  • 23 out of 274 (8% of class) got this question wrong

  • Which spacecraft landed on the surface of Venus and took pictures of the surface?

    • Venera 9
  • 8 out of 274 (3% of class) got this question wrong

  • Caloris Basin and Hellas Basin are both

    • large impact craters


Class average was 75.4

  • Class average was 75.4

  • Grades ranged from 45s to 100



For people who took all 4 tests:

  • For people who took all 4 tests:

  • Class average now (80% Exam, 20% HW) is 80.6

  • Grades range from a 98.3 to a 54.2

  • This average will go up when the lowest exam grade is dropped after the final and the lowest HW grade is dropped



Cumulative

  • Cumulative

  • Monday - 12/14

  • 4:00 pm

  • Hasbrouck 20

  • Review Session

  • Sunday -12/13

  • 3:00 pm

  • Hasbrouck 134



Due today

  • Due today



I have put HW #18 (late) and #19 (late)

  • I have put HW #18 (late) and #19 (late)

  • All calculations

  • On blog



Life on Mars

  • Life on Mars

  • Life on Europa and Titan

  • Life on extrasolar planets





On March 2, 2009:

  • On March 2, 2009:

  • NEA 2009 DD45 came within

  • ~70,000 km of the surface of

  • the Earth

  • Diameter between 21-47 m



This object is believed to be the same size as the object that exploded over Siberia in 1908

  • This object is believed to be the same size as the object that exploded over Siberia in 1908

  • About 1,000 times as powerful as the bomb dropped on Hiroshima



2-3 m object that entered the atmosphere over Sudan on October 7, 2008

  • 2-3 m object that entered the atmosphere over Sudan on October 7, 2008

  • Burned up before it reached the ground

  • Fragments found



Initially thought to have a high probability (up to 2.7%) of hitting Earth in 2029

  • Initially thought to have a high probability (up to 2.7%) of hitting Earth in 2029

  • ~270 meters in diameter

  • Impact probability with Earth for April 13, 2036 is calculated as 1 in 45,000



Comets can also hit us

  • Comets can also hit us



Comets have been known since the earliest days of mankind

  • Comets have been known since the earliest days of mankind

  • Usually thought to be unlucky

  • Attacks by heavenly beings on terrestrial people























Edmund Halley figured out that the orbit of the comet of 1682 was nearly the same as those of two comets which had appeared in 1531 and 1607

  • Edmund Halley figured out that the orbit of the comet of 1682 was nearly the same as those of two comets which had appeared in 1531 and 1607

  • Halley concluded that all three comets were in fact the same object returning every 76 years

  • Halley predicted its return for 1757.

  • Halley's prediction of the comet's return proved to be correct, although it was not seen until December 25, 1758



Usually named after discoverer (or person who computed its orbit)

  • Usually named after discoverer (or person who computed its orbit)

  • Comet Halley

  • Number given when discover (or discoverers) have discovered numerous comets

  • Comet Shoemaker-Levy 9



Short period comets – periods < 200 years

  • Short period comets – periods < 200 years

  • Long-Period Comets – periods > 200 years



Comet West

  • Comet West

  • Blue tail –gases, white tail – dust particles



Giotto image

  • Giotto image

  • Dimensions - 16 x 8 x 8 km



Called Dirty Snowballs by Fred Whipple

  • Called Dirty Snowballs by Fred Whipple

  • Because they are mixtures of ice and dust



Rock











Our first look at a comet nucleus…

  • Our first look at a comet nucleus…

  • (Comet Halley will return in 2061)









Crystalline olivine and pyroxene condensed at high T, most likely in the inner solar nebula

  • Crystalline olivine and pyroxene condensed at high T, most likely in the inner solar nebula

  • Glassy silicates were not subjected to high temperature, may be ancient interstellar grains







Mission to investigate

  • Mission to investigate

  • Comet Wild 2

  • Return samples of the comet

  • back to Earth











Two-micrometer comet particle, collected by the Stardust spacecraft, is made up of the silicate mineral forsterite (Mg2SiO4) (olivine)

  • Two-micrometer comet particle, collected by the Stardust spacecraft, is made up of the silicate mineral forsterite (Mg2SiO4) (olivine)



January 2, 2004

  • January 2, 2004

  • 98 days post-perihelion

  • Heliocentric distance: 1.86 AU

  • Geocentric distance: 2.6 AU

  • Closest approach: 236 km

  • Encounter speed: 6 km/s













NASA space probe

  • NASA space probe

  • designed to study the

  • composition of the

  • interior of the

  • comet Tempel 1.



2 parts:

  • 2 parts:

    • 370 kg copper-core "Smart Impactor" which impacted the comet
    • "Flyby" section, which imaged the crater created by the impactor.




http://www.nasa.gov/mov/117657main_Maas_DI_Long_320.240.mov

  • http://www.nasa.gov/mov/117657main_Maas_DI_Long_320.240.mov

  • http://www.nasa.gov/mov/121520main_HRI-Movie.mov

  • http://www.nasa.gov/mov/121527main_MRI_impact.mov



Comet Tempel 1 or Comet 9P/Tempel 1

  • Comet Tempel 1 or Comet 9P/Tempel 1





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