Pluto-Charon-Hydra Occultation Updates

[rodsky]

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In case you didn't know, a rather rare event has been occurring over Cebu skies since June 23 and is still being observed right this moment. The event is the minor planet Pluto and its moons (Charon and Hydra) occulting (eclipsing) 13th magnitude stars (very small, make that tiny!). Unfortunately, one cannot observe this event unless one has a very powerful telescope.

But, a team from SwRI Planetary Science Directorate is here in Cebu City, to conduct observations on these events. They are now staying at Chris Go's place at Ma. Luisa, Banilad, where they have set up their observation equipment.

Heading this team is Dr. Leslie Young and Mellisa Brucker, who are both members of the New Horizons Pluto Probe team.

I'll be updating this post as soon as more data comes in. This could be an historical event, perhaps the first time Pluto has ever been imaged in the Philippines, and right here in Cebu City.

The reason why the data from these observations are important is because Dr. Young's team (and other teams across the world) is trying to figure out if Pluto has an atmosphere, and occultations are great tools for determining this.

-RODION

[paparoy]

post nya pics sir.. ask lang unta ko if pluto is still considered as planet?ü

[rodsky]

post nya pics sir.. ask lang unta ko if pluto is still considered as planet?ü

Dwarf planet. There's a distinction.

Dwarf planet - Wikipedia, the free encyclopedia

Updated: I got confused between minor planet and dwarf planet. Corrected my error. Sorry for the confusion.

-RODION

[handsoff241]

In case you didn't know, a rather rare event has been occurring over Cebu skies since June 23 and is still being observed right this moment.

Nope we didn't know. Our feeble intentions busy with daily chores didn't observed Pluto's circus. And we don't have a powerful telescope (God help us!)

Thanks for letting us know! Cheers!

I'll just camp this thread and wait for your uploaded pictures. Or I can subscribe.

[observer]

Wow. It would be interesting to know the equipment they'd be using to image Pluto. It says here about Pluto: "To see it, a telescope is required; around 30 cm (12 in) aperture being desirable. It looks star-like and without a visible disk even in large telescopes, because its angular diameter is only 0.11 inch. Distance, and current limits on telescope technology, make it impossible to directly photograph surface details on Pluto."

I know Chris Go personally. He still has that distinct high-pitch voice, if you know what I mean. Just not sure if he'd lend me his barlow lens if I promise not to drop it. I'm sure NASA will send him a replacement...hehe.

I have to ask rodsky or anyone who knows about Pluto's downgrade to dwarf planet. Was it because of Pluto's small mass/size/diameter or was it because of Pluto's position within the Kuiper belt that took it out of our list of planets in our solar system or was it something else?

[rodsky]

Wow. It would be interesting to know the equipment they'd be using to image Pluto. It says here about Pluto: "To see it, a telescope is required; around 30 cm (12 in) aperture being desirable. It looks star-like and without a visible disk even in large telescopes, because its angular diameter is only 0.11 inch. Distance, and current limits on telescope technology, make it impossible to directly photograph surface details on Pluto."

I'll just camp this thread and wait for your uploaded pictures.

I'm still checking on what I can post and what I cannot post. In recent times, in professional astronomy circles, there are certain "grace" periods put in place when data from observations are not yet to be released to the public/media, so that it can first make the rounds of peer review (i.e. among fellow professional astronomers, the IAU, etc), to make sure something like the "Mars Germs" media sensation fiasco won't ever happen again.

Just not sure if he'd lend me his barlow lens if I promise not to drop it. I'm sure NASA will send him a replacement...hehe.

Let's meet up soon and go to Chris' place together(he has a new C14!)

I have to ask rodsky or anyone who knows about Pluto's downgrade to dwarf planet. Was it because of Pluto's small mass/size/diameter or was it because of Pluto's position within the Kuiper belt that took it out of our list of planets in our solar system or was it something else?

This issue is very convoluted and complex, but the main driving force in this issue was the discovery of 136199 Eris. Eris (dwarf planet) - Wikipedia, the free encyclopedia You see, the trouble with Eris is, it's LARGER than Pluto, and thus the discoverer really wanted his name in the history books, as the discoverer of the 10th planet in the solar sytem. However, the catch is, if Eris is to be considered a planet, then other "small planets" of similar nature would have to be included in the list. This sparked off a year-long debate within the professional astronomy community and the IAU--in fact their first proposal was to have 12 planets in the solar system:

The initial 12-planet proposal


However, this made the matter worse, because there are also trans-neptunian objects that belong to a vague category that, if the initial criteria was applied to, then they should also be considered as planets. Thus more discussion and debate ensued, and eventually, the solar system planets became classified into three distinct groups:

1. Dominant planets - 8 of them...Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune.

2. Dwarf Planets - Dwarf planet - Wikipedia, the free encyclopedia

3. Minor Planets - Minor planet - Wikipedia, the free encyclopedia

And this is the current official diagram we have now, of our solar system:


This is the analysis diagram of how the IAU resolved this issue:


The story is really more complex than what I have just described. Best if you read the ff:
Definition of planet - Wikipedia, the free encyclopedia

-RODION

[observer]

Let's meet up soon and go to Chris' place together(he has a new C14!)

He has some very important visitors. I'll have to call him up first to see if I can crash. The last time I spoke with him was about three years ago, in a barbershop of all places, and we didn't talk about astronomy; it was all about catching up and the subprime crisis.

This issue is very convoluted and complex, but the main driving force in this issue was the discovery of 136199 Eris. Eris (dwarf planet) - Wikipedia, the free encyclopedia You see, the trouble with Eris is, it's LARGER than Pluto, and thus the discoverer really wanted his name in the history books, as the discoverer of the 10th planet in the solar sytem. However, the catch is, if Eris is to be considered a planet, then other "small planets" of similar nature would have to be included in the list. This sparked off a year-long debate within the professional astronomy community and the IAU--in fact their first proposal was to have 12 planets in the solar system:

Pluto must be miffed at Eris for showing up. Not only did Eris downgraded Pluto's status, it's also made the Dominant Planets Club more exclusive.

It's interesting, from that Wiki link on Eris, how the Hubble image of Eris is able to show a good amount of luminosity. I mean it's 96 AU from the sun and it's shining like Vega. Where does it get all those photons bouncing off it from? It must be one shiny rock. I thought planets that are extremely far from earth can only be detected through its disturbance on some nearby planet's orbit or techniques like gravitational microlensing.

By the way, I get confused by the units of measurements used for distance. Why do they sometimes use lightyears or AU or parsecs? Which one is used in what context or purpose? And is stellar parallax the only technique used in measuring distance?

[rodsky]

He has some very important visitors. I'll have to call him up first to see if I can crash. The last time I spoke with him was about three years ago, in a barbershop of all places, and we didn't talk about astronomy; it was all about catching up and the subprime crisis.

He actually invited people to a lecture at USC Physics Department, to meet Leslie Ann Young and Melissa Brucker, both of the Pluto New Horizons Spacecraft team, who were here to observe the occultation events. I couldn't make it due to schedule conflicts. They are his important visitors at the moment.

Pluto must be miffed at Eris for showing up. Not only did Eris downgraded Pluto's status, it's also made the Dominant Planets Club more exclusive.

It's interesting, from that Wiki link on Eris, how the Hubble image of Eris is able to show a good amount of luminosity. I mean it's 96 AU from the sun and it's shining like Vega. Where does it get all those photons bouncing off it from? It must be one shiny rock. I thought planets that are extremely far from earth can only be detected through its disturbance on some nearby planet's orbit or techniques like gravitational microlensing.

My yet-untrained but fair guess--water ice.

By the way, I get confused by the units of measurements used for distance. Why do they sometimes use lightyears or AU or parsecs? Which one is used in what context or purpose?

It all depends on the target objects being observed. If you're discussing trans-Neptunian, Kuiper Belt or Oort Cloud objects, it would be cumbersome to use LYs because of the proximity to the earth. But if you're discussing interstellar objects, then it's better to use LY, and if the distances are extremely large, then Parsecs would be more suitable, although LY would also work. One reason why it would be better to use Parsecs is when you're trying to figure out star distances via the parallax method.

And is stellar parallax the only technique used in measuring distance?

I believe this is a good read on that subject...
Cosmic distance ladder - Wikipedia, the free encyclopedia

ADDITIONAL INFO:

While I'm still pondering on what to share, here's a report from NASA about SOFIA's successful attempt to capture Pluto's shadow during occultation with a star:

NASA - SOFIA Successfully Observes Challenging Pluto Occultation


SOFIA is a highly modified Boeing 747SP aircraft that carries a telescope with a 100-inch (2.5-meter) reflecting mirror that conducts astronomy research not possible with ground-based telescopes. By operating in the stratosphere at altitudes up to 45,000 feet, SOFIA can make observations above the water vapor in Earth's lower atmosphere.

Must be pretty challenging to fly a flying telescope

-RODION

[glassjaw]

by the time pluto comes near earth .. humankind will be extinct ..

[moy1moy1]

by the time pluto comes near earth .. humankind will be extinct ..

whutt??