jovians

Terraformed Europa

What if we could see how the Jovian moon Europa would look like if its ocean weren’t frozen over? This may just be a mere illustrative depiction as done by an artist but it still raises our curiosity and imagination. If creatures lived on such an ocean world without the freezing temperatures who knows what kind of species would rise what kind of intelligence they’d have, adaptation skills, and size! But let me not downplay the fact that species have been shown to survive even on freezing temperatures. This is why I love artistic representations on observations we’ve witnessed in nature. The 'what if' sensations shoot through the roof, and that’s okay.

Europa as It Is Today: Jupiter’s icy moon Europa is slightly smaller than the Earth’s Moon. Like the Earth, Europa is thought to have an iron core, a rocky mantle and a surface ocean of salty water.

Unlike on Earth, however, this ocean is deep enough to cover the whole surface of Europa, and being far from the sun, the ocean surface is globally frozen over.

(Summary: NASA) Image: Anderpeich

Happy Birthday, Galileo Galilei, born February 15, 1564.  

On the nights of January 7/8, 1610, Galileo Galilei noted in his notebooks the discovery of the first 4 Jovian moons, which he named after the powerful Medici family, naming them Medicean I, II and III.  The name Europa (second from right) comes from Greek mythology-Europa was abducted by Zeus (the Greek name for Jupiter) in the form of a bull and bore him many children.  Io (the yellow moon on the left) is also named for a child of Zeus (Jupiter) the daughter of Inachus, who was raped by Jupiter. Jupiter, in an effort to hide his crime from his wife, Juno, transformed Io into a heifer.  Calllisto (on the far right) was named for another seduction of Jupiter.  Callisto was the daughter of Lycaon, who was a follower of Artemis, famous as goddess of the hunt and for her chastity.  To punish Callisto for lying with Jupiter, Artemis banished her.  Without protection, Jupiter was forced to change Callisto and her son into bears to hide them from his wife Hera’s fury.  Eventually, Jupiter placed them both in the sky as the Ursa Major and Minor, the Big and Little Bears (known today as the Big and Little Dippers).  Ganymede (largest moon pictured here, third from right) was the fourth moon discovered by Galileo, named for the shepherd boy known for his incredible beauty and kidnapped by Jupiter.  These names would not become common for several hundred years.  Today, Jupiter has fifty named moons:

1. Io  2. Europa 

3. Ganymede 
4. Callisto 
5. Amalthea 
6. Himalia 
7. Elara 
8. Pasiphae 
9. Sinope 
10. Lysithea 
11. Carme 
12. Ananke 
13. Leda 
14. Thebe 
15. Adrastea 
16. Metis 
17. Callirrhoe 
18. Themisto 
19. Megaclite 
20. Taygete 
21. Chaldene 
22. Harpalyke 
23. Kalyke 
24. Iocaste 
25. Erinome 
26. Isonoe 
27. Praxidike 
28. Autonoe 
29. Thyone 
30. Hermippe 
31. Aitne 
32. Eurydome 
33. Euanthe 
34. Euporie 
35. Orthosie 
36. Sponde 
37. Kale 
38. Pasithee 
39. Hegemone 
40. Mneme 
41. Aoede 
42. Thelxinoe 
43. Arche 
44. Kallichore 
45. Helike 
46. Carpo 
47. Eukelade 
48. Cyllene 
49. Kore 
50. Herse 

and an additional 16 provisional moons:

1. S/2003 J2 
2. S/2003 J3 
3. S/2003 J4 
4. S/2003 J5 
5. S/2003 J9 
6. S/2003 J10 
7. S/2003 J12 
8. S/2003 J15 
9. S/2003 J16 
10. S/2003 J18 
11. S/2003 J19 
12. S/2003 J23 
13. S/2010 J 1 
14. S/2010 J 2 
15. S/2011 J1 
16. S/2011 J2 

All images courtesy NASA.  Thanks also to NASA for additional historical background

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Europa’s Chaotic Terrain

Hard layers of ice make up the surface of Jupiter’s frozen moon Europa. Glacial cracks and ridges scar its frigid white plains, carving paths across an icy shell that conceals a deep ocean of liquid water. Closer inspection of the moon’s fractured topography reveals highly disrupted areas, called chaos terrains, where blocks of ice appear to have broken off, drifted and refrozen to the surface.

Searching for an explanation of how these features formed, researchers studying images of Europa taken by NASA’s Galileo spacecraft have come up with an answer. As plumes of warm ocean water rise to the subsurface, massive lakes develop inside the moon’s crust—some larger than North America’s Great Lakes combined. Over time, the ice directly above these lakes collapses, splintering into floating geometric fragments that rotate, raft and resettle into all kinds of chaotic configurations.

Electrodynamic interactions in the Jovian system

Electrodynamic interactions play a variety of roles in the Jovian system: generation of plasma at the Io torus, magnetosphere / satellite interactions, dynamics of a giant plasma disc coupled to Jupiter’s rotation by the auroral current system, generation of Jupiter’s intense radiation belts.

The exploration of the Jovian System and its fascinating satellite Europa is one of the priorities presented in ESA’s “Cosmic Vision” strategic document. The Jovian System indeed displays many facets. It is a small planetary system in its own right, built-up out of the mixture of gas and icy material that was present in the external region of the solar nebula. Through a complex history of accretion, internal differentiation and dynamic interaction, a very unique satellite system formed, in which three of the four Galilean satellites are locked in the so-called Laplace resonance.

The energy and angular momentum they exchange among themselves and with Jupiter contribute to various degrees to the internal heating sources of the satellites. Unique among these satellites, Europa is believed to shelter an ocean between its geodynamically active icy crust and its silicate mantle, one where the main conditions for habitability may be fulfilled. For this very reason, Europa is one of the best candidates for the search for life in our Solar System. So, is Europa really habitable, representing a “habitable zone” in the Jupiter system? To answer this specific question, we need a dedicated mission to Europa. But to understand in a more generic way the habitability conditions around giant planets, we need to go beyond Europa itself and address two more general questions at the scale of the Jupiter system: to what extent is its possible habitability related to the initial conditions and formation scenario of the Jovian satellites? To what extent is it due to the way the Jupiter system works? ESA’s Cosmic Vision programme offers an ideal and timely framework to address these three key questions.

Building on the in-depth reconnaissance of the Jupiter System by Galileo (and the Voyager, Ulysses, Cassini and New Horizons fly-by’s) and on the anticipated accomplishments of NASA’s JUNO mission, it is now time to design and fly a new mission which will focus on these three major questions. LAPLACE, as we propose to call it, will deploy in the Jovian system a triad of orbiting platforms to perform coordinated observations of its main components: Europa, our priority target, the Jovian satellites, Jupiter’s magnetosphere and its atmosphere and interior. LAPLACE will consolidate Europe’s role and visibility in the exploration of the Solar System and will foster the development of technologies for the exploration of deep space in Europe. Its multi-platform and multi-target architecture, combined with its broadly multidisciplinary scientific dimension, will provide an outstanding opportunity to build a broad international collaboration with all interested nations and space agencies.

LAPLACE: A mission to Europa and the Jupiter System for ESA’s Cosmic Vision Programme (.pdf)

Credit: MPS/ESA/NASA

Everything you knew about the Gas Giants was wrong!

Obviously a lot of you would have known about this, but still; ‘Dramatic title!’

Anyway, I was browsing a website which hosted a bunch of astronomical ‘facts’ and one these so called facts stated: “Jupiter, Saturn, Uranus and Neptune are made up of just gas with no solid surface to land on.” And considering how wrong this is it annoyed me. so I decided to make this post…

So what is contrary to common knowledge about the Gas Giants?

- For starters, Neptune and Uranus are commonly not even classed as gas giants any more! instead they are called Ice Giants due to their differences in both chemical composition and physical state compared to traditional Jovian planets.

Even regular gas giants are barely that. Their name deceives them for they only consist of roughly 2-10% gas on the surface. The huge pressure of the gas forces hydrogen and helium into a liquid state beneath the surface, and even further down it becomes what is known as ‘Metallic Hydrogen’ before you reach the core which is, probably, just rock and ice.

 

OTP TWELVE QUESTIONS

I don’t actually know who started this, but 12 question otp challenge thing! Send me the name of a ship and I’ll answer them with what I think.

Who cooks normally?
How often do they fight?
What do they do when they’re away from each other?
Nicknames for each other?
Who is more likely to pay for dinner?
Who steals the covers at night?
What would they get each other for gifts?
Who kissed who first?
Who made the first move?
Who remembers things?
Who started the relationship?
Who cusses more?
What would they do if the other one was hurt?