Dawn Arrives at Ceres: Coverage

originally posted by: Soylent Green Is People

originally posted by: Ross 54
According to the published schedule, Dawn should be making images of Ceres today. Past experience suggests that we might get to see this on about the 15th or 16th. Further images are planned for the 14th. These will probably be released around the 19th or 20th. Because of uncertainties about the rotational period of Ceres, the bright spots may, or may not be visible in these images. It will be interesting to see which is the case.

Since the reaction wheels have failed last year, the ability to orient the craft so the antenna is pointing back toward Earth has been compromised, and their high-bandwidth communication opportunities are limited. Dawn may have been already pre-programmed to take the images (programmed the last time the up-link antenna orientation was correct), but the ability to transmit those images back may need to wait until it moves itself into a better position.

The reaction wheels were used to turn the craft without using thrusters. If the reaction wheels were working, the craft could be turned more easily without the use of the attitude control thrusters and without using up the very limited supply of hydrazine fuel. Unlike the main electric ion engines, the attitude control thrusters use chemical fuel -- hydrazine. Therefore, if they want to conserve the hydrazine fuel, they need to wait for the craft's orbit to naturally put the up-link antenna in the correct orientation.

I'm not sure if that is the only factor holding up the release of images, but that is at least one factor.

Great post. BTW for anyone interested, Dawn and Kepler had the same flawed reaction wheels. The manufacturer of the reaction wheels that failed on Dawn and Kepler and a number other missions is Ithaco Space Systems of Ithaca, New York.. Ithaco became notable for having manufactured the reaction wheels of the Kepler spacecraft, the Hayabusa spacecraft, the Mesosphere Energetics and Dynamics (TIMED) satellite and the Dawn spacecraft, which developed problems or even failed.

They laid off their employees in 2012.

Good riddance.

originally posted by: JadeStar

originally posted by: All Seeing Eye
a reply to: Ross 54

Some new explanation may become necessary.

The way it looks now, its not "may", but "must".

We cannot solve our problems with the same thinking we used when we created them.

Albert Einstein

www.brainyquote.com...

As just about everyone can agree upon is, I'm no Astrophysicist. But in saying that it would also be true that I have studied the subject for a considerable time.

The above quote in this particular case is a door opening statement, or to some here at this web site, and invitation to exit the box. And in this case, to me, Albert is telling us the answers are not going to be found in standard models of Astrophysics.

What I fear the most is that the Astrophysics community will shy away from what is being documented, and they will do this out of fear. A fear of facing a dilemma of ignorance, because what they see does not fit into the accepted model of planet formation. The thinking that created this model, will not answer the question as to what the light is, or isn't.

But that's not how it works.

If something challenges an accepted model (for instance the plethora of "Hot Jupiters" found orbiting very close to other stars), then we find better models. That's how science works.

We're not rooted to dogma nor "stuck on stupid".

When something doesn't fit an accepted model we like it because that's the surprise of investigation. If all we found was what we expected then science would be a very boring field.

Thank you for the reply.

If something challenges an accepted model , then we find better models. That's how science works.

Certainly I agree, but when I hear "Out Gassing" and "Ice Volcanoes" without any supporting documentation, or any real substantiated facts or information, it makes me wonder who really has the larger imagination.

If your going to build a new model it must be based on "Some" type of evidence, or reasoning. I see none for these trains of thought. I know all too well about applying assumptions to the unknown, and as my very wise science teacher pointed out, Assumptions make ass's out of You and Me.

What is documented is a light, that is either reflective, or a source. That is all we have as evidence at this point. Plus, as Ross54 pointed out, there is no temperature difference between the surrounding areas and the light itself.

This is the photographic evidence we have to work with. This is where the new model should start, not out of someones imagination.

Thanks to "Soylent Green Is People" for the enhancement.



www.abovetopsecret.com...

We're not rooted to dogma nor "stuck on stupid".

I apologize if anyone thinks my remarks are personal to any one person, they are not. But I will not hide my disdain and distrust of the institution. And I don't think I have to go into any great detail about my concerns with institutions.

But that's not how it works.

Now in the simplest logic, should a new model be based in what we see and the facts? No one seems to want to discuss what is seen in this photo. It will have to suffice until new photos are received. Is this not how its suppose to work?

I've been following this thread. Haven't had a lot to say because honestly most of you guys have been talking over my head.

But the last couple pages seem to be more in layman's terms. Combining the multiple theories. Someone tell me if I could be anywhere in the ballpark?

The core of the crater may be leftover CO2 from a comet impact or the impact itself. When in direct sunlight it stimulates the CO2 to reflect like a comet does.

The difference in a thermal temperatures could be explained by the same reaction in this climate change video. (CO2 gas blocks the heat signature from infrared camera)

a reply to: Greathouse

Some of the preliminary hypotheses were that the bright spots were some sort of off-gassing, similar to a comet. However, their models suggested that materials that would off-gas like that would be found closer to the poles and higher latitudes, not closer to the lower latitudes, like where these bright spots are.

However, so little is known of Ceres that their models could be wrong. Their current hypotheses are based on incomplete data and assumptions, but when they get more data about Ceres, those hypotheses and assumptions could be found to have been incorrect.

There may be other current assumptions about Ceres that will be found to be incorrect once better data is obtained. One example we have been discussing here is the possibility that the bright spots are some sort of water-ice volcano or geyser. The models we currently have on Ceres tells us that maybe the interior of Ceres is not warm enough to power such geysers/water volcanoes. However, some scientists think that once we start studying Ceres, we may find that there are ways the interior of Ceres could be warm enough to power such phenomenon.

It has also been hypothesized that maybe the bright spots are some sort of mineral salt deposits, again deposited by water. However, from the pictures taken last month, it seemed that the bright spots were at least as high as the rim of the crater they are in, which seems to point to a plume rather than a deposit.

The bottom line is that they simply don't know yet, and that's why this mission should be exciting.

In fact, Dawn researchers totally understand that once they get better data on Ceres, their "understanding" od Ceres (or what they thought they understood) will most likely need major revisions. At the 46th annual Lunar and Planetary Conference that just wrapped up a couple of weeks ago, the organizers of the conference humorously titled a session on Ceres: " "Your last chance to talk about Ceres before Dawn data wreck your theories" (Who says scientists have no sense of humor?).

So yeah -- they realize their current theories on Ceres will need revision after this mission.

Here is a list of papers presented at that session on Ceres:

Ceres and Dawn: Your Last Chance to Talk About Ceres Before Dawn Data Wreck Your Theories

They could very well be glass chunks synthesized after a meteorite impact
a reply to: Soylent Green Is People

originally posted by: All Seeing Eye

originally posted by: JadeStar

originally posted by: All Seeing Eye
a reply to: Ross 54

Some new explanation may become necessary.

The way it looks now, its not "may", but "must".

We cannot solve our problems with the same thinking we used when we created them.

Albert Einstein

www.brainyquote.com...

As just about everyone can agree upon is, I'm no Astrophysicist. But in saying that it would also be true that I have studied the subject for a considerable time.

The above quote in this particular case is a door opening statement, or to some here at this web site, and invitation to exit the box. And in this case, to me, Albert is telling us the answers are not going to be found in standard models of Astrophysics.

What I fear the most is that the Astrophysics community will shy away from what is being documented, and they will do this out of fear. A fear of facing a dilemma of ignorance, because what they see does not fit into the accepted model of planet formation. The thinking that created this model, will not answer the question as to what the light is, or isn't.

But that's not how it works.

If something challenges an accepted model (for instance the plethora of "Hot Jupiters" found orbiting very close to other stars), then we find better models. That's how science works.

We're not rooted to dogma nor "stuck on stupid".

When something doesn't fit an accepted model we like it because that's the surprise of investigation. If all we found was what we expected then science would be a very boring field.

Thank you for the reply.

If something challenges an accepted model , then we find better models. That's how science works.

Certainly I agree, but when I hear "Out Gassing" and "Ice Volcanoes" without any supporting documentation, or any real substantiated facts or information, it makes me wonder who really has the larger imagination.

If your going to build a new model it must be based on "Some" type of evidence, or reasoning. I see none for these trains of thought. I know all too well about applying assumptions to the unknown, and as my very wise science teacher pointed out, Assumptions make ass's out of You and Me.

But they're not assumptions. An assumption would be that they could be due to artificial lighting. Now THAT takes imagination and a leap of logic to something we have no evidence for elsewhere in the universe.

Unlike such a wild idea, we have plenty of evidence and even photos of ice volcanoes and outgassing on bodies in our solar system including Ceres and Europa.

Enceladus:




Hartley 2:




Not alien "lights" but hella interesting to me nonetheless. What could be lurking in those subsurface waters? If only we could collect some samples.......

a reply to: JadeStar

But they're not assumptions

They are, if they are applied to Ceres. Do you see any of this activity in the photos? One answer does not fit all.

Ceres is in a class of its own. Imho.

a reply to: JadeStar

In all the examples given, of the sublimation of ice or of outgassing from the interiors of solar system bodies, there is one common characteristic. All are dispersed over a substantial portion of the surface.
We see this in photographs of various comets, including Hartley 2 . This is also the case in images of outgassing from Enceladus and Europa. In the case of Ceres, the Herschel Space Telescope defined 35 degree (or about 90 km) wide bands as containing water vapor.
Why, one wonders, should such features on Ceres, once we got a closer look at them, be somewhat under 4 km in diameter ? It seems to be in the nature of water vapor to expand itself greatly, once it's released, and, on solar system bodies, to have numerous sources, or broad ones, or both.
The true size of the bright spots is unknown, since they are currently optically unresolved. They will apparently be smaller by the time they are resolved, than the current minimum figure of about 3.7 km. If they should remain unresolved, or are only just resolved at a diameter of about 2 km, this will prove a very interesting situation.
Given a markedly reduced area, the reflectivity (albedo) would have to be raised from the current figure of around 40 percent, to over 100%. That would be impossible for a merely reflective object, of course.

originally posted by: All Seeing Eye
a reply to: JadeStar

But they're not assumptions

They are, if they are applied to Ceres. Do you see any of this activity in the photos? One answer does not fit all.

Please read the linked article regarding Ceres outgassing water. It's not an assumption it's been observed so its not the "wild theory" you make it out to be.

Or you know.... this one at NASA....

Jan 22, 2014: Water Detected on Dwarf Planet Ceres

Ceres is in a class of its own. Imho.

May I ask where you studied astrophysics and planetology?

originally posted by: JadeStar

originally posted by: All Seeing Eye
a reply to: JadeStar

But they're not assumptions

They are, if they are applied to Ceres. Do you see any of this activity in the photos? One answer does not fit all.

Please read the linked article regarding Ceres outgassing water. It's not an assumption it's been observed so its not the "wild theory" you make it out to be.

Or you know.... this one at NASA....

Jan 22, 2014: Water Detected on Dwarf Planet Ceres

Ceres is in a class of its own. Imho.

May I ask where you studied astrophysics and planetology?

59 years at the "School of Hard knocks".

I did read the material and right off the bat it states "suggest". Later it states "Theory". And I'll add, this article is from Jan. 22, 2014: And as fast as things are now happening, slightly obsolete.

Until now, ice had been theorized to exist on Ceres but had not been detected conclusively.

They theorize the core is made of water, therefore what is seen, must be water.

Theories are just that, theories. Please... They are not facts. And I don't need to go to school to be educated to the difference.

So, I guess I'm not buying what they are selling. I'm tired of theories, show me the facts. Then, I might buy.

a reply to: All Seeing Eye

Too bad that you seem to have stopped reading after the first few lines...

The have detected water vapor, not theorized about it.

It took Herschel's far-infrared vision to see, finally, a clear spectral signature of the water vapor. But Herschel did not see water vapor every time it looked. While the telescope spied water vapor four different times, on one occasion there was no signature.

The strength of the signal also varied over hours, weeks and months, because of the water vapor plumes rotating in and out of Herschel's views as the object spun on its axis. This enabled the scientists to localize the source of water to two darker spots on the surface of Ceres, previously seen by NASA's Hubble Space Telescope and ground-based telescopes.

The publication is available here: www.nature.com...

a reply to: moebiusI'm not saying water or water vapor does not exist on Ceres, and yes, I read it.

Prove the light is water, or a "Water Volcano". Your trying to force a theory on a phenomenon that might need a new theory.

Oh, maybe its luminescent water, no volcano needed. Yea, its a biological light emitting bug.

a reply to: All Seeing Eye

It brightens and dims based on the sun angle, so it seems to be a reflection.

It also seems to reflect light at an altitude at or above the rim of the crater it is in. Therefore, the current hypotheses based on the evidence is that it is some sort of plume or offgassing (or some other phenomenon ejecting reflective material to an altitude at or near the crater rim).

originally posted by: Soylent Green Is People
a reply to: All Seeing Eye

It brightens and dims based on the sun angle, so it seems to be a reflection.

It also seems to reflect light at an altitude at or above the rim of the crater it is in. Therefore, the current hypotheses based on the evidence is that it is some sort of plume or offgassing (or some other phenomenon ejecting reflective material to an altitude at or near the crater rim).

Now that you mention it, the photos of just before you can see the light need to be enhanced, while it is full exposure to the sun light. I haven't seen that one.

Soylent, can you grab one of the frames of the creator as it comes into view from the right? Everyone is focused on the light, what about the area the light is emitting from? Can you enhance that one as well??

It really appears as though the crust has been breached, a photo from the right would be revealing as to what is or is not coming out..

a reply to: Soylent Green Is People

I was able to edit the GIF file everyone has seen, and you might be surprised what you see.



Watch the frames to the right of the crater with the lights, as it "Turns On".. Seems something is missing. Who created the original GIF??

Seems we have a few key frames missing...

I'm not so certain that an icy plume, extending upward from the crater,
would be brighter at high Sun angles than at low ones. Couldn't the sides of such a plume reflect as much, if not more sunlight than its top?

To me, the bright spots look flat, and appear to be presented closer and closer to edge-on, as they dim. We may simply be seeing less and less of their surface area.

originally posted by: All Seeing Eye
a reply to: Soylent Green Is People

I was able to edit the GIF file everyone has seen, and you might be surprised what you see.

Watch the frames to the right of the crater with the lights, as it "Turns On".. Seems something is missing. Who created the original GIF??

Seems we have a few key frames missing...

I'm not sure what you mean by "as it [the bright spots] turn on". the first frames of that GIF are the frames with the right spots already on. We don't see them "turn on".

Here are the individual images that make up that GIF. You can see that the first images include the bright spots. The part of that GIF that we see just "before" the bright spots appear is actually the end of the GIF, which (after it ends) it just loops back around to begin again with the frames in which the spots are visible:

originally posted by: Ross 54
I'm not so certain that an icy plume, extending upward from the crater, would be brighter at high Sun angles than at low ones. Couldn't the sides of such a plume reflect as much, if not more sunlight than its top? To me, the bright spots look flat, and appear to be presented closer and closer to edge-on, as they dim. We may simply be seeing less and less of their surface area.

Dawn mission scientists say it does not look to be flat at the bottom of that crater. When viewed from the side, it appears to be peeking out above the rim of that crater, leading them to believe that it may be something that is about as high or higher than the rim of the crater.

In Dawn's latest pictures, the bright spot is visible even from the side, meaning it probably protrudes above the crater. "What is amazing is you can see this feature while the rim is very likely in front of the line of sight," said Andreas Nathues, who is in charge of the mission's camera. "We believe this could be some kind of outgassing."

Note: This article is a couple of weeks old, so when they say "latest pictures", they mean the images from late February/early March.

Source (click for link)

a reply to: Soylent Green Is People

I'm not sure what you mean by "as it [the bright spots] turn on"

Let me try to explain. And by the way, I have studied each frame.

The frames immediately before you can see the light are missing, at end of gif. The crater prior to the light becoming visible is not the same crater. The crater with the light does not have 3 round smaller craters at 11:00, 14:00, and 17:00, military time. The entire photo does not fit. There appears to be missing frames that would show the crater left of center. The crater represented is similar but not the same one. The original GIF was running too fast to see the omission. I slowed it down and enlarged it to see the crater before it was at a 90 deg angle from the left. That photo or photos is, are missing.

The GIF does not represent an entire rotation of Ceres.

The brilliance of the light from the bright spots suggest high activity, in a proposed plume scenario. This, and the expansive behavior of icy plumes on other small solar system bodies, make it seem unlikely that the supposed plume on Ceres would rise up a very few kilometers from the surface, slightly above the crater rim, and no farther.
Dr. Nathues' is not the only interpretation of the data available to NASA. Dr. Carol Raymond, the Deputy Principal Investigator for the Dawn mission has said that no elevated feature, plume or mound was apparent at the site of the bright spot. She called exposed surface ice a more likely explanation.