Stars - By German

On Friday, April 30, 2010, our science teacher, Mrs. DiPietro gave us a presentation about stars. She told us that stars differ in size, mass, color, temperature and brightness. The colors that stars have are blue, yellow, and red, and that their life cycle is as long as sun's, which is 9 billion years. If the star is blue, then it tells that the star is young a very hot, about 35,000 degrees Celcius. Blue stars can also die out sooner than other stars. If the star is yellow, then it is middle-age star. If the star is red, it is cold, around 3,000 degrees Celcius, and it is about to die.

Our teacher also explained us about the sizes of stars (see pictures at the left). First, she told us about Supergiant stars. Their size is 1000 times the diameter of the Sun. These star giants include Rigel, Betelgeuse, and Antares. Then our teacher told us about giant stars. They are 10 to 100 times as large as a sun, and these include Sirius, the brightest star in our sky. We learned that the stars come from Nebulae, and sometimes from EGGs (Evaporating Gaseous Globules)

We also learned Binary stars are stars that stay together because of gravity between them, and that there are 88 accepted constellations in our sky.

Homework:

APOD 6 due Tuesday, May 4, 2010, at 08:00 a.m.

Next scribe is Aidan

Tuesday April 27, 2010

Today in science class, we had a shortened period becuase of a Croatian field trip. However when we got back, Ms. D continued to show us a powerpoint of the two comets Halley and Hale-Bopp. The powerpoit explained their revolution and when they will reach Earth again. We also were reminded about the five parts of a comet.

The five parts of a comet are:

1.Nucleus-middle part which is composed of gasses, dirt, and ice

2.Dust tail- composes of dust

3. Ion tail- different color, heating up and exciting gasses

4. Coma- the gasses around the nucleus. They cause the shine

5. Hydrogen cloud- the gasses that are released and left behind

Now a little bit about the two comets Hale-Bopp and Halley.

Comet Halley:

-It is the most famous comet in history

-It proved Edmund Halley's math was correct becuase the comet came back to Earth

-It originates from the Oort Cloud

-It is now currently located in the Kuiper Belt

-The revolution is 76 Earth years (it last came in 1986 and it will come back again in 2061)

-It is the same age as the Sun (4.5 billion years old)

Comet Hale-Bopp:

-It was discovered in July 23, 1995

-Two people discovered it independently Alan Hale and Thomas Bopp

-It is 4.5 billion years old

-The diameter of the nucleus is 40-80 kilometers

-Its revolution around the Sun takes 2,392 Earth years

Here is a video of Hale-Bopp in the sky
http://www.youtube.com/watch?v=Zen-veDX0zE&feature=related

Here is a video of the revolution pattern of the comet Halley
http://www.youtube.com/watch?v=WuZVl4jWrJw

After talking about the comets, we continued our forum and concluded it. We talked about Mars, Jupiter, and Neptune. Not having much time left, we quickly reviewed the names of the celestial bodies and their symbols'. We were told that there is a review session on Wednesday during lunch if you want to come.

REMEMBER, TOMMOROW WE HAVE A CELESTIAL BODIES OPEN NOTE TEST! REMEMBER TO COME PREPARED! The test will be timed so organize your stuff well.

The next scribe is German.

Science Class...

During the Science period of Friday, April 23 2010, we additionally explored the activities being held later on this year. In the first minutes of class, Ms. D mentioned that our scheduled "Celestial Body Test" had once again been postponed as the Croatian classes are taking a trip to a theatre. Despite the fact that we are not having our test on Tuesday, Ms. D still highly recommended you prepare yourself (the chart) over the weekend. She took this further by saying that we CANNOT share our notes with anyone in the class as they will be taken away from both you and the person you shared them with. Prior to that, Ms. D made it clear to take blogger more seriously, look at what you are posting, chose your videos wisely, and make sure your commenting is appropriate, as she will be showing this Blog to others. Keep in mind, you need 3 Eighth grade posts, 3 Seventh grade posts, and 2 Sixth grade posts for Blogger. If experiencing trouble commenting on the 6th and 7th grade blogs, scroll to the bottom of the page where the verification button is as this will allow an access to commenting. Astronomy then ends on May the 7th, and we will be moving forward into Chemistry. As discussed, we will only be having Chemistry, and very little Astronomy in our Science Final.

As class prolonged, Cornelia

and Abigail gave there Celestial body presentations, discussing them amongst each class table. Cornelia's given Celestial body focused on Comets. Comets are leftovers from the creation of the Solar system around 4.5 billion

years ago. They are made of ice and are coated with dark organic matter. She also described how Comets are predicted to have shared water and other organic compounds with the Solar System and Earth's early life.

The 5 Parts of a Comet

1.) Nucleus

2.) Coma

3.) Hydrogen Cloud

4.) Dust Tail

5.) Ion Tail

Cornelia's favorite Comet was Hale Bopp. Like other Comets, it has a revolution of 2,392 Earth days and comes from the Oort Cloud. Comets are given the name of icy snowballs or mud balls and when they are in contact with the Sun (around 15 AU's close), they dissolve into gas.

Gas determines the color of the Comet

Red light - Hydrogen

Blue light- Carbon Dioxide

Yellow Light - Oxygen

As Cornelia concluded, Abigail began to tell us about Mars, her Celestial Body. The Planet Mars is particularly smaller compared to other Planets. It is a red color, due to its soil composed of rust. The planet has large dust and wind storms including diminutive tornadoes. Mars has been researched for any sign life. Yet all that has been found was frozen water beneath its surface. This planet holds onto 2 moons. One of them, Phobos, is predicted to smash into Mars since it is swinging closely around its atmosphere. Once this occurs, gravitational forces will shatter the moon to particles. Moreover, Mars consists of 3 rovers or robotic machines developed for taking better pictures and accurate research.

Afterward, the class continued the open forum by adding additional information to both Mars and Comets along with reviewing Questions and Answers brought up by the class.

Dates

-Thursday April 29th is our Open Note Celestial Body Test and remember to come prepared. Ms.D will also hold a review session for this test on Wednesday, April 28th

-Extra Credit is due Friday May 14th. Take a picture with Saturn, Neptune, Uranus, or Pluto for 3 extra bonus points and email the picture to dani.dipietro@aisz.hr or ddipeitro.aisz@gmail.com

-Tuesday April 27th - 5th APOD is due. This one can come from any date from 2000-2010

-April 30th - 3rd Blog comment to 7th or 8th grade Blogs

Here is an Awesome Video on Mars and a helpful one on Comets, also focusing on other Celestial Bodies.

http://www.youtube.com/watch?v=pWbCeveFptA

http://www.youtube.com/watch?v=ZXsTN-OxBGs

Next Scribe is Arnie

Astronomy

Today, in science class, April 22nd, 2010, we continued our forum discussion in connection with the planet packet. However, we first focused on a very important event which is happening today, the 40^th anniversary of Earth day. Earth day was started in the US in 1970 but the UN celebrates international Earth Day on March 20^th/ 21^st. On this special day they also ring a peace bell.

In connection with Earth Day, we will also be planting plants tomorrow and take them home as a way to give back to the environment.

In our discussion about Earth day we brought up some important things such as one major problem at the moment: global warming. It is referred to as the extremes in climate which have drastically changed in the past years. The causes of global warming are being discussed and there are many theories; but, Ms. D pointed out that since carbon emissions have increased in the past years there have been extreme changes in weather patterns. If this process continues we may even end up resembling Venus; The hottest planet which melts metal on its surface, which would not be a pleasant thought!

Lastly, we watched videos and a slideshow in connection with Earth Day. The links to the videos are just below:

Wombat- http://www.global-mindshift.org/memes/wombat.swf

Chips - http://www.youtube.com/watch?v=Yu5J5HQk6VY

Photography - http://www.youtube.com/watch?v=G8IozVfph7I

During class, Ms. D also gave us corn starch Styrofoam which indeed is very edible. (:

As we moved on to the Forum we mainly focused on Exosolar planets and Daniel explained his topic during class. Extra notes you missed if you were not in class today or just didn’t pay attention:

- The smallest exosolar planet they have found is Jupiter size

- The 4 spacecrafts with the sole mission of leaving this solar system are called Voyager 1, Voyager 2, Pioneer 10, and Pioneer 11. These all went in different directions in our solar system!

- Further explanation of 3 ways to find Exosolar planets:

1) Radical Velocity Method

-It is Earth based

- They find rays from the Parent star (Star which Exosolar planets orbits around) and measure the wavelength. If this wave length is abnormal or weird they suspect that they have found an Exosolar planet.

-The top of a wavelength is called a crest and the bottom a trough.

2) Astrometry Method

-Space based

- Looks at the wobbling of a star

- Star wobbles because gravity affects it

3) Transit method

- Most surefire method

- Both Earth and solar system based

- Watches the changing brightness of a star

We also had a very cute visitor from 3^rd grade named Alice. She came to observe our astronomy forum class for the last 20 minutes. The class introduced themselves and their planets to Alice while we continued the forum.

Homework & Upcoming events

April 23^rd : second blogger comment for the 4^th quarter is due!

April 27^th at 8 AM: The fifth APOD for this unit any date from 2000-2010 may be used! Also, next week is the last APOD that will be due for science this year!

April 28^th : Celestial Body test study session at lunch

April 29^th : open note Celestial Body Test

April 30^th : third blogger comment due

May 4^th or 7^th: A friend of Mrs. Sprljan may come in to talk to us about astromomy. He specializes in wormholes and Black holes.

May 11^th : Chemistry unit starts

May 14^th : Extra credit due. Each picture next to a planet is worth 2 points. The planets which count as extra credit are Saturn, Uranus, Neptune and Pluto. Email these pictures to dani.dipietro@aisz.hr or ddipietro.aisz@gmail.com for extra credit. Good luck!

Here are the maps for the extra credit assignment: http://www.phy.hr/~mpozek/planeti/

Hebrew: Ohevet otchem kulam (Love ya guys) and good luck (:

Next scribe is Emma

Field Trip!

Yesterday, Tuesday April 20th we went on a science field trip to a planetarium. We had 2 guides the first guide talked about space and the first spacecrafts that were launched etc. The guide told us about pollo 11 the first spacecraft to ever land on the moon! Apollo 11 was launched on July 16th 1969. Apollo 11 was owned by United states

As the guide continued on he showed us the first satelite ever launched. It was called Sputnik ll and was launched in late november 1957. Sputnik ll had a animal launched in it by the name of Lakia. Sputnik ll was the size of about 5 bowling balls mashed together to create on huge bowling ball. The dog was taken to space to see if humans could actully space travel, however the poor animal died after a couple of hours due to overheating and stress and panic. Which then lead to many arguments over human space travel however as stated before there was an agreement to make the first space travel in 1969. As we continued walking through the planeterium/museum the guide was speaking in croatian as Mrs. Sprljan translated he spoke about the Apollo rocket they had a 3 meter model in their musem he said that it was ten times bigger and that the astronauts were on the very tip of the rocket and how when astronauts returned to earth they ussually landed on Land and not sea leading to some major injures, they needed to be carried out of the spacecraft. After the first guide finished presenting the satelites and spacecrafts we enterd this globe type of object were he presented the stars/the planets. Then we met up with the 2nd guide.

With the second guide we explored mining and the use of electircty against physical power. As a demonstration Where Holly ran in this huge hamster wheel and about 5 boys were ment to stop her. As we moved on we saw how there was a patern of development, how everyday things got simpler and simpler. Then We got to the old car engines and the guide demonstrated how some of the first cars used leavers to get the engine started he also mentioned how most people drove themselves over because they had their car left in 1st gear so it would just drive over them. Then we saw some other intresting things. But finally the mining part came he showed us how they made 12 year old boys work in mines because of the low hight of the mine. And also how they would have mules which would not sea day for their full lives. He introduced the diffrent tools such as pick-axes, shovels. And how the miners needed to work 8 hours a day with the exeption of sunday. He lead us into a artifical mine beneath the museum which was not high at all and most of us needed to crouch. We saw a two meter block of rock missing in part of the wall he explained to us how a miner needs to dig that much within 3 hours and how there was no talking and lunch was 30 minutes. The miners ussually watched for mice running because if they ran that ment danger aslo they carried candels in the mines to see what gasses were down there somtimes its would blow up everything and somtimes it would turn off. As the guide was taking us through the last part of the tour he said that there was water driping from the seelings and how there was dust everywhere and the sound of drills pierced your ears.

http://www.youtube.com/watch?v=RMINSD7MmT4

http://www.youtube.com/watch?v=RMINSD7MmT4

http://www.youtube.com/watch?v=ygBxN5UiOaM

There is no Homework for Thursday however check on moodle for upcoming tests

The next scribe will be Ines

Scribe Post Friday 16th, 2010

On Friday the 16th in Science Class we continued to add information to our notes for the upcoming open note test which will be happening on Tuesday, April 27th. Throughout the class we mainly focused on the symbols of the celestial bodies however we also talked about some of the planets about multiple things like dwarf planets etc.

Here is a list of the symbols of the Celestial Bodies:

Here are some notes that we had discussed:

All the terrestrial planets are: Mercury, Venus, Earth, and Mars

All the gas planets are: Jupiter, Saturn, Neptune, and Uranus

The Sun has the longest revolution in our solar system

Mercury is the smallest planet

Venus is the biggest object we see in the sky from Earth (with the exception of the Sun and the Moon) because the atmosphere bounces off the light from the Sun

Venus is a good example of global warming

Venus rotates clockwise while all the other planets rotate counter clock wise

The Earth’s atmosphere is made of oxygen, hydrogen, carbon dioxide, nitrogen, H²O, O³, and Methane

The Earth’s land is made of: basalt, and iron

Saturn is the least dense planet in our galaxy

Galileo who discovered the rings of Saturn thought that they were the planets ears

Cassini which is a probe launched on October 15^th, 1997

is still orbiting around Saturn and taking the best pictures

ever taken of Saturn

Saturn has 62 moons however 53 moons have been named until now

Jupiter is the biggest planet

Jupiter has the 4 biggest moons

The first name of Uranus was called Georgium Sidus

(The Georgian Planet) in the honor of the British King; George III

Uranus has two polls which are named the summer poll where there’s always summer and the winter poll where there’s always winter (42 years each)

Uranus has no magnetic field

The Methane in the atmosphere makes Neptune and Uranus blue

Eris is the biggest dwarf planet in our solar system

Haumea is the smallest dwarf planet in our solar system

Eris is the reason why Pluto isn’t a planet anymore because once they found Eris they knew it wasn’t supposed to be a planet and then they saw the similarities between Eris and Pluto so they decided that they are both dwarf planets

Three reasons why dwarf planets are dwarf planets:

1. Clear orbital path around the sun day do not exist

2. They are too small

3. The orbital paths are not on the same place as the planets

Videos (Just Click on the title):

Cassini

Why Pluto is a dwarf planet

What is a dwarf planet

Don't forget to check moodle for homework!!!!

Click Here to open Moodle

Next Scribe will be by: Jacob

Don't forget to comment!!!!