Super earths? (APOD 20 Mar 2006)

Comments and questions about the APOD on the main view screen.
Post Reply
Spacecake
Asternaut
Posts: 3
Joined: Mon Mar 20, 2006 8:12 pm
Location: Redwood Coast

Super earths? (APOD 20 Mar 2006)

Post by Spacecake » Mon Mar 20, 2006 8:27 pm

I am brand new to the forum but have been an APOD fan for years. My apologies if I have created this topic in the wrong way. I didn't see any other topic on today's picture (and I did read the rules).

Today's picture and explanation confused me, and I wonder if someone could clear up a few questions.

1. By "super earths" does the writer mean large planets in general or large planets that aren't gas giants?

2. I'm really not a science genius, just an interested layman. When it says 13 times the mass of the earth, that says nothing about the dimensions of the super-earth, correct? It could be similar in size to the earth but composed of matter with higher mass.

I guess I'm just confused as to what is meant by the term "super earth." Obviously the description shows that there is a great deal of mystery surrounding these planets, but I was wondering if there might be a clearer description of what they are believed to be — and not be.

User avatar
BMAONE23
Commentator Model 1.23
Posts: 4076
Joined: Wed Feb 23, 2005 6:55 pm
Location: California

Post by BMAONE23 » Mon Mar 20, 2006 8:40 pm

Anyone else, feel free to correct me if I'm wrong.

The term "Earth" is used to reflect a terrestrial type rocky planet as opposed to a gas giant like Jupiter.

"Super" refers to its general size/mass.

So "Super Earth" does mean a rocky body with more mass than our Earth.

As for part 2, "13 times the mass" does in fact refer to the presumed mass of the planet as we still can not directly view the planet to determine its exact size. We can presume size/mass based on the planets influence on the star it orbits.

User avatar
orin stepanek
Plutopian
Posts: 8200
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Post by orin stepanek » Mon Mar 20, 2006 10:02 pm

I find the art interesting. It looks like the planet and moon and star were added to a galactic photograph.

http://antwrp.gsfc.nasa.gov/apod/ap060320.html

If I'm wrong; that's very good art.

Orin

l3p3r
Science Officer
Posts: 142
Joined: Tue Nov 22, 2005 12:47 pm
Location: Hobart, Australia

Post by l3p3r » Tue Mar 21, 2006 7:04 am

yeah looks like a photo to me
if only they would go and take some photos of the super earths themselves :)

Spacecake
Asternaut
Posts: 3
Joined: Mon Mar 20, 2006 8:12 pm
Location: Redwood Coast

Post by Spacecake » Tue Mar 21, 2006 7:45 am

BMAONE23 wrote:Anyone else, feel free to correct me if I'm wrong.

The term "Earth" is used to reflect a terrestrial type rocky planet as opposed to a gas giant like Jupiter.

"Super" refers to its general size/mass.

So "Super Earth" does mean a rocky body with more mass than our Earth.

As for part 2, "13 times the mass" does in fact refer to the presumed mass of the planet as we still can not directly view the planet to determine its exact size. We can presume size/mass based on the planets influence on the star it orbits.
Thanks BMAONE. That's very helpful. I wonder how the gravity difference affects how life could evolve there.

harry
G'day G'day G'day G'day
Posts: 2881
Joined: Fri Nov 18, 2005 8:04 am
Location: Sydney Australia

Post by harry » Tue Mar 21, 2006 8:19 am

Harry : Smile and live another day.

User avatar
BMAONE23
Commentator Model 1.23
Posts: 4076
Joined: Wed Feb 23, 2005 6:55 pm
Location: California

Post by BMAONE23 » Tue Mar 21, 2006 2:59 pm

Spacecake,
I would imagine that if any were to form it would be limited to simple to minor complex ocean going life forms in a geothermally active frozen over ocean. It is believed that the planet orbits in an area that would be equal to the distance of our asteroid belt but around a star that is considerably cooler than our own (a brown dwarf). I believe that it is assumed that there is no appreciable atmosphere as it is too cold. If there is a scrim of atmosphere, the surface might harbor bacterial life.

As for the possibility of an ocean, the water might tend to counteract the effects of a stronger gravity though pressure might be a factor, denser gravity = heavier water per sq'

User avatar
orin stepanek
Plutopian
Posts: 8200
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Post by orin stepanek » Sun Jul 09, 2006 4:10 pm

Super planets around other stars seem to be all that man can find; but, that may change. While surfing I found this site that I thought was of interest to the exploration of the universe.
http://www.guardian.co.uk/science/story ... 38,00.html
If this becomes a project and works out man would have an idea of what was out there before sending an exploratory probe.
Orin

User avatar
orin stepanek
Plutopian
Posts: 8200
Joined: Wed Jul 27, 2005 3:41 pm
Location: Nebraska

Post by orin stepanek » Thu Jul 20, 2006 2:21 pm

Along With finding Super Earths Around other stars; now they are finding abundance of water vapor around another star.
http://www.spaceref.com/news/viewpr.html?pid=5485
There seems to be an abundance of carbon there also; Both elements are needed for life. Unfortunately if there was life near this star it is probably extinct as the comets there are all being vaporized.
Orin

Post Reply