MercuryMythology - Hermes – The messenger god)

1st ever color photo of Mercuryby MESSENGER probe; 2008

MercuryTransit across Sun

1st ever color photo of Mercuryby MESSENGER probe; 2008

MercuryMapped by Mariner 10

Mercury vs. Earth & Moon1/6 size of Earth

MercuryImages by Mariner 10

Mercury Statistics:* .4 A.U. From Sun

* 1/3 Size of Earth* Orbital Period = 3 Months*Rotation Period = 88 Days

* Surface Gravity = 1/6 of Earths* The planet is too small to hold an atmosphere

Atmosphere:•There is no atmosphere

•heat is not trapped on the planet.

• it is VERY HOT during the day, and VERY COLD during the night

Mercury is NOT the hottest or coldest planet.

core

1. Very Large2. Solid3. Iron

Mercury has a disproportionately large Iron core.

It should be cooled and solid. However, MESSENGER flyby data indicates the core is partially molten.

This contradicts current theories.

Lobate scarps

Definition – curved cliffs

Cause =When the core cooled,it shrunk, causing thecrust to collapse.

MercuryMissions to Mercury

Mariner 10Launched Nov 1973Flyby March 1974

MESSENGERLaunched Aug 2004Orbit insertion March 2011

MercuryMESSENGER

Orbit Insertion –> Launch – E – V – V - M – M - M

MercuryMESSENGER

Orbit Insertion –> Launch – E – V – V - M – M - M

Venus

Aphrodite – The goddess of LoveThe Morning/Evening Star/Sister Planet

Venus Statistics

• Distance - .73 A.U. From Sun

• Size – Same Diameter as Earth

More Statistics

• Orbital Period – .6 Years

• Rotation Period – 243 days

• Surface Gravity – .9 of Earths

Venus Atmosphere

• Runaway Greenhouse Effect– Visible light from sun hits the surface – Surface reradiates the energy in the form of

infrared– Clouds block some of the IR from escaping– Surface gets hotter

Runaway Greenhouse Effect Results

• CO2 Atmosphere

• NO WATER!

CO2 Atmosphere

No Water!

Atmospheric Conditions

1. Pressure 90x that of Earths

2. Very dry, no surface water

3. Sulfuric Acid in Clouds Atmosphere

4. Temperature 900 F

5. Wind Speed up to 250 Miles per Hour.

Venus Weather

Images/Video from Venus Express Orbiter

Twin cyclones: two storms with low-pressure centers that causes a circular pattern of winds to form.

Weather

• Vortex Storms:– huge swirling vortex of

clouds around Venus' southern pole.

– changes shape within just a few days

– The rotation of Venus deflects them sideways so they swirl together, like water going down the drain of a bathtub.

http://www.astroarts.org/content/vex/VIRTIS_movie_500_b.gif (vortex)

Venus Solar Stormsi. Venus does not have a magnetic field.

ii. Solar Wind erodes away the atmosphere.

Venus MissionsVenera 9-14 –1978 - 1982 – Landers (First & only images of Surface)

Venus Surface

Images from Venera 13 probe

Venus Missions

Magellan – 1989 – Orbiter – Created Radar Map of Surface

Venus MissionsMagellan – Radar Map

~8 min magellan_mapping_venus.wmv

Venus MissionsMagellan – Radar Map

Venus Missions

Pioneer Venus 1 & 2 - 1978 – Orbiters & Descent Probes

Venus Missions

Venus Express – 2005 to present – Orbiter

Animation ofVenus ExpressStudying Venus

Venus MissionsVenus Express

~5 min

VenusAlthough Venus is often called Earth’s Twin or Sister planet. Theonly similarities is the size. Almost every other feature makes Venus very different from Earth.

Earth

MESSENGER animationLeaving earth.

Earth

Earth

Atmosphere -78% nitrogen, 21% oxygen

Distance -1 au from sun (93,000,000 miles)

Contains water in all 3 phases

Surface Gravity – 9.8 m/s

Rotation – 1 day

Orbit – 1 year

EarthGreenhouse Effect

-Has Liquid Water (Some Water Vapor in Atmosphere)

-Water vapor keeps planet warm (main greenhouse gas)

-Ozone Layer prevents water from Disassociating

Earth

Greenhouse

Icehouse

Technically, Earth is currently undergoing an Icehouse effect.however, most of the time, Earth is in a Greenhouse effect.

EarthIcehouse effect :- Anytime there is a continent over any of the poles, the resulting ice sheet reflects large amounts of Solar Radiation into space

-causing the Earth to cool down.

Image from NASAEarth Observatory

Earth

Greenhouse

Icehouse

Technically, Earth is currently undergoing an Icehouse effect.however, most of the time, Earth is in a Greenhouse effect.

Gondwanaland Pangaea Antarctica

EarthIcehouse effect

As long as Antarctica is at the South Pole, the Earth will continually be thrown into Glaciation periods.

We are currently at the end of an Interglacial period.

Earth

70 Atmospheres of CO2 is trapped in Earths Rocks.

If all of this CO2 were released, which planet would we look like?

Only place we know of that supports life - 4 reasons:

1. Correct distance from sun2. Natural/Stable greenhouse effect3. Ozone Layer & Magnetic Field4. Presence of Liquid Water

Planet Guidelines

• The IAU therefore resolves that planets and other bodies in our Solar System be defined into three distinct categories in the following way:

• (1) A planet1 is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit.

• (2) A dwarf planet is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

• (3) All other objects3 orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".

Planet Guidelines

• (1) A planet is a celestial body that – (a) is in orbit around the Sun, – (b) has sufficient mass for its self-gravity to

overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and

– (c) has cleared the neighbourhood around its orbit.

Planet Guidelines

• (2) A dwarf planet is a celestial body that – (a) is in orbit around the Sun, – (b) has sufficient mass for its self-gravity to

overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape2, (

– c) has not cleared the neighbourhood around its orbit, and

– (d) is not a satellite.

Planet Guidelines

• (3) All other objects3 orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".

Video Links• Earth from Spaceshuttle

– http://www.youtube.com/watch?v=wHyonFhWp6w

• http://www.youtube.com/watch?v=9ddEjVwpX9I• http://www.youtube.com/watch?v=F5d6cd7XXiA

&feature=related• http://www.youtube.com/watch?v=Mj52CgKHzH

Q• http://www.youtube.com/watch?v=lwwioJhQzeg

&feature=PlayList&p=0D959158C1FC558F&playnext=1&index=21

Mars

Go to inner_mars.ppt