POLL: Should they increase the importance of Ceres?

[Liyak]

From what I see, Ceres is strangely left apart on exploration roadmaps, which are coped by Mars and the Moon (not arguing here, but...). Not only it could have liquid water, but exploring this body would be far cheaper than Mars, even with sample return missions. Even so, there's not a "Ceres Exploration Program" for the future, nor money expected for such exploration (being another probe or any rover). Having a slight suspicion of liquid water (even only in theory), I see Ceres being blatantly ignored by nearly all space agencies... What do you think?

 

[Shpaget]

Isn't it a bit too far away?
Personally I believe even Mars is too far for our next step, but hey... that's just me.

 

[nimbus]

Cheap access to space before anything else..

 

[MeteorWayne]

Agree with both of the above comments. Let's see what we find out when Dawn gets there while we figure out how to get manned craft to space at a reasonable cost.

 

[kg]

Agree with both of the above comments. Let's see what we find out when Dawn gets there while we figure out how to get manned craft to space at a reasonable cost.

This is the first time I've heard of the Dawn Mission!
http://en.wikipedia.org/wiki/Dawn_Mission

According to this wiki Ceres is its last stop in 2015 after first visiting Vesta in 2011. Any chance nasa will extend the mission?

 

[MeteorWayne]

This is the first time I've heard of the Dawn Mission!
http://en.wikipedia.org/wiki/Dawn_Mission

According to this wiki Ceres is its last stop in 2015 after first visiting Vesta in 2011. Any chance nasa will extend the mission?

Wow, that must be some big rock you are hiding under! :lol:

Here's the Mission thread:

viewtopic.php?f=6&t=738

It's got almost 500 posts, and over 125,000 views!!

 

[aphh]

I calculated the synodic period for Ceres to be only 299 days ( 1 / syn. period = 1 / 1680.5 d + 1 / 365 d).

Hence launch window opportunities open quite often. The reason Dawn goes to Ceres so slowly is that it is not a direct route and ion propulsion, while fuel efficient, is slow method to propel a spacecraft. The travel time could be cut significantly with direct launch to Ceres using chemical propulsion.

 

[kelvinzero]

Im really interested in Ceres but I still chose the third option, Dawn is enough for now. It would be nice if there were more probes on the way, it would be nice if they could get there faster, but there are other space goals for our money and I dont expect what we find there will dramatically change our priorities. We have the Moon, Phobos and Mars, all nearer at hand.

It just doesn't seem the right time to start making extravagant plans for Ceres until we have had a look at it.

..but I still wish Dawn could get there faster!

 

[kg]

I guess this answers my question...

http://en.wikipedia.org/wiki/Dawn_Missi ... ion_system
"The Dawn spacecraft is propelled by three DS1 heritage xenon ion thrusters (firing only one at a time). They have a specific impulse of 3100 s and produce a thrust of 90 mN.[33] The whole spacecraft, including the ion propulsion thrusters, is powered by a 10 kW triple-junction photovoltaic solar array.[34] To get to Vesta, Dawn will use 275 kg (606 lb) Xe and another 110 kg (243 lb) to get to Ceres,[35] out of a total of 425 kg (937 pounds) of on-board propellant.[36] All in all, it will perform a velocity change of over 10 km/s, far more than any other spacecraft has done.[35] Dawn is NASA’s first purely exploratory mission to use ion propulsion engines."

I take it that last 88lbs of Xe isn't enough to get it to any other objects in the asteroid belt? For some reason I thought a solar powered ion propulsion spacecraft got better mileage.

 

[MeteorWayne]

Once the Ceres part of the mission is complete, they will look to find another target within reach of the remaining propellant. They've got a few years to work on it

 

[Shpaget]

On my first read of wiki article yesterday evening this caught my eye, but since it was so late I misunderstood (misread) 1,81 km/s as... well I'm not sure what, but I was deeply depressed with the inefficiency and weakness of it's ion thruster.

During this first interplanetary cruise phase Dawn has spent 270 days, or 85% of this phase using its thrusters. It has expended less than 72 kilograms (158 pounds) of Xenon propellant for a total change in velocity of 1.81 kilometers per second (4050 miles per hour).

Now that I'm not so tired it seems rather impressive to gain 6500 km/h with only 70 kgs of propellant. I guess that the fact that the price of xenon is affordable compared to the price of hauling cheaper, but less efficient chemical propellant up there.

Go Dawn.

I wanna see some kewl hi-res Vesta pictures in couple of years.

 

[MeteorWayne]

The Dawn team released a 2nd anniversery announcement with updated numbers on Sept 27th. See the last post in Dawn thread in the Missions and Launches forum for the latest.

 

[MeteorWayne]

Just for fun:

Vesta's orbit:

http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=V ... ;cad=0#orb

And Ceres:

http://ssd.jpl.nasa.gov/sbdb.cgi?sstr=C ... ;cad=0#orb