Space and Astronomy in general

Watched the ISS pass over tonight. It was the first time I'd done that. Very easy to see tonight, with a magnitude of -3.4 and no moon.

I let the people who don't need glasses focus and use the binoculars, so I had naked-eye viewing only. They said they couldn't really see details.

If you want to see when it will be visible in your location, check out http://www.heavens-above.com/

Saw an ISS passover a few years ago with, I want to say Endeavour? Was pretty cool seeing the two dots fly across the sky.

Katy wrote:

Aww, poor guy has to sing his own happy birthday song all by himself up there.

Voyager 1 is officially interstellar.

NASA's Voyager 1 spacecraft officially is the first human-made object to venture into interstellar space. The 36-year-old probe is about 12 billion miles (19 billion kilometers) from our sun.

New and unexpected data indicate Voyager 1 has been traveling for about one year through plasma, or ionized gas, present in the space between stars. Voyager is in a transitional region immediately outside the solar bubble, where some effects from our sun are still evident.

I love that they comment on the Voyager team sorting through data... the fact that there still is a Voyager team and that it's still sending data after 36 years. Good work, NASA.

Katy wrote:

Voyager 1 is officially interstellar.

Another quote:

Voyager 1 does not have a working plasma sensor, so scientists needed a different way to measure the spacecraft's plasma environment to make a definitive determination of its location. A coronal mass ejection, or a massive burst of solar wind and magnetic fields, that erupted from the sun in March 2012 provided scientists the data they needed. When this unexpected gift from the sun eventually arrived at Voyager 1's location 13 months later, in April 2013, the plasma around the spacecraft began to vibrate like a violin string. On April 9, Voyager 1's plasma wave instrument detected the movement. The pitch of the oscillations helped scientists determine the density of the plasma. The particular oscillations meant the spacecraft was bathed in plasma more than 40 times denser than what they had encountered in the outer layer of the heliosphere. Density of this sort is to be expected in interstellar space.

Science FTW!

Apparently "dense plasma" in interstellar terms means about 1.3 electrons per cubic inch.

The probe's plasma wave instrument detected these oscillations, and researchers used the measurements to figure out that Voyager 1's surroundings contained about 1.3 electrons per cubic inch (0.08 electrons per cubic centimeter).

That's far higher than the density observed in the outer regions of the heliosphere (roughly 0.03 electrons per cubic inch, or 0.002 electrons per cubic cm) and very much in line with the 1.6 electrons per cubic inch (0.10 electrons per cubic cm) or so expected in interstellar space.

OG_slinger wrote:
Gaald wrote:

In the news footage it looks like they were able to eject the capsule which I would assume held the payload. I wonder if they were able to save it, cause damn that would be super expensive if they didn't.

Nope. They went kablooey.

The three GPS satellites were valued at around $200 million and that's about how much the launch vehicle was insured for. The Russian government is going to have to eat the actual cost of the launch vehicle, which they typically sell for about $100 million.

I know the Proton failure is old news now, but perhaps some of you are as nerdy as me and get excited about root cause investigations.

IMAGE(http://www.spaceflight101.com/uploads/6/4/0/6/6406961/6238382_orig.jpg)

Here's the full article.

TL;DR - One of the accelerometers was installed upside down. The casing found in the wreckage shows a dent where the misaligned pin left an imprint. "The commission found that it would take a considerable effort by the technician to install the sensors incorrectly."

"The commission found that it would take a considerable effort by the technician to install the sensors incorrectly."

The US really doesn't like GLONASS: a navigation system that they don't control scares the heck out of them. And a technician had to work very hard to put the accelerometer in wrong.

Probably just a coincidence. Probably.

"Never attribute to malice that which can be adequately explained by stupidity."
- Robert J. Hanlon

If you still want more about Voyager 1, then swing over the Reddit. They have an AMA with the JPL crew responsible for the Voyager mission. One of them has been with NASA since 1970 and cut his teeth planning the predecessor of Voyager, the Planetary Grand Tour, and a couple have with NASA since Voyager was launched.

Isn't one of the older Star Trek movies (maybe even the first one) based on the Voyager craft?

Not sure if this is the right thread to ask this but can anyone link to a supported theory of where all the mass in the universe comes from? I'm having trouble conceptualizing the universe as truly "infinite" with no beginning as my brain just can't come to terms with that. Prior to big bang?

The usual top google answers just don't do it for me. Something from nothing does not compute.

Rallick wrote:

"Never attribute to malice that which can be adequately explained by stupidity."
- Robert J. Hanlon

Yeah, but that's a LOT of stupidity. I'm not sure that's an adequate explanation, in this case.

ESA wrote:

Isn't one of the older Star Trek movies (maybe even the first one) based on the Voyager craft?

Not sure if this is the right thread to ask this but can anyone link to a supported theory of where all the mass in the universe comes from? I'm having trouble conceptualizing the universe as truly "infinite" with no beginning as my brain just can't come to terms with that. Prior to big bang?

The usual top google answers just don't do it for me. Something from nothing does not compute.

Well, there's some thought that the total energy level of the Universe may actually be zero, that if you could somehow see it from outside, and add everything up, you'd come up with exactly nothing.

We're just a very _interesting_ nothing, with lots of detail.

Malor wrote:
Rallick wrote:

"Never attribute to malice that which can be adequately explained by stupidity."
- Robert J. Hanlon

Yeah, but that's a LOT of stupidity. I'm not sure that's an adequate explanation, in this case.

How about Occam's Razor then? If it's a matter of a part being easily installed 180º out and the only reference is an alignment pin you're doing it wrong. Plenty of people think that if something isn't working the proper solution is more force. If the options are that some intern thought a bolt was sticky versus he's a CIA mole sabotaging the Soviet space program I'll bet on stupidity every. single. time.

Phoenix Rev wrote:

A little backstory on how that data was collected from the Reddit AMA. It was recorded on a 36 year-old tape drive that still works and NASA has to continually re-transmit the data because the Deep Space Network doesn't have enough bandwidth to capture the signal--all 7200 bps of it--at one time.

I don't know who made it, but the tape recorder on Voyager is still doing fine, thank you. The high resolution plasma wave data is recorded on it a couple times a week (all of 48 seconds each time) and played back a few times per year. Interestingly, the lowest playback rate is 7,200 bits per second, but the fastest telemetry rate to the ground (using 1 70-meter and 1 34-meter DSN station ganged together) is 1,400 bps. So while the first 800 bytes are being transmitted, the next 4000 fall on the floor. While this sounds like a waste, those 800 bytes are really precious! And, yes, eventually we won't have enough power to run it.
Malor wrote:
Rallick wrote:

"Never attribute to malice that which can be adequately explained by stupidity."
- Robert J. Hanlon

Yeah, but that's a LOT of stupidity. I'm not sure that's an adequate explanation, in this case.

Or it could simply be the case that the technician who installed it just wanted to go home early.

ESA wrote:

Isn't one of the older Star Trek movies (maybe even the first one) based on the Voyager craft?

Star Trek: The Motion Picture is based on the Voyager space probe.

Quintin_Stone wrote:
ESA wrote:

Isn't one of the older Star Trek movies (maybe even the first one) based on the Voyager craft?

Star Trek: The Motion Picture is based on the Voyager space probe.

Voyager 6, to be exact.

TMP wiki, with plot

Technically Voyager 6, which doesn't really exist. But yeah.

Star Trek wiki on V6

Rogue planet, all alone in interstellar space, discovered with Pan-STARRS

IMAGE(http://www.popularmechanics.com/cm/popularmechanics/images/iW/rogue-planet-mdn.jpg)

Approximately 80 light years from Earth, a planet wanders alone. Without a star to tether it to a single orbit, the newly discovered PSO J318.5-22 drifts aimlessly across the sky at a sluggish 20 kilometers per second. This rogue planet has six times the mass of Jupiter and is the nearest free-floating planetary-mass object ever seen.

(That's from the popularized article, the study report is here, which calls it "an extremely red late-L dwarf", not a planet. I'm not sure where the distinction between a very cold dwarf star and a very warm gas giant planet lie, actually.)

Still it's pretty cool. All alone, and not that far away.

Katy wrote:

(That's from the popularized article, the study report is here, which calls it "an extremely red late-L dwarf", not a planet. I'm not sure where the distinction between a very cold dwarf star and a very warm gas giant planet lie, actually.)

It's bright enough to give a similar appearance to a brown dwarf, but its mass is estimated at only 6.5 Jupiters, and its spectrum suggests that it's a recently formed planet still radiating away the heat from its formation, rather than a star with its own energy source.

There isn't a clear borderline between the largest planets (with negligible interior energy source) and the smallest brown dwarfs (with enough deuterium fusion going on in the core to extend their luminous life span). Theoretical models predict that the transition would come at a mass of about 13 Jupiters, and the IAU has provisionally recommended using that as the dividing line.

Despite their low observability, I seem to recall reading somewhere that brown dwarf stars are the most common stellar objects in the universe. I guess that would make the brown dwarf star the bison of the cosmos.

CaptainCrowbar wrote:
Katy wrote:

(That's from the popularized article, the study report is here, which calls it "an extremely red late-L dwarf", not a planet. I'm not sure where the distinction between a very cold dwarf star and a very warm gas giant planet lie, actually.)

It's bright enough to give a similar appearance to a brown dwarf, but its mass is estimated at only 6.5 Jupiters, and its spectrum suggests that it's a recently formed planet still radiating away the heat from its formation, rather than a star with its own energy source.

I asked an astronomer friend of mine the same question, and this is what she said:

There's a very blurry line between the two. Basically, it all comes down to how massive the object is. If it's larger than ~13 Jupiter masses, we call it a brown dwarf (or L dwarf). It's too small to be a real star that burns Hydrogen, but large enough that it could burn things like Deuterium in its core. A hot gas giant planet would be too small to burn anything in its core.

Taking a quick look at the paper, the planet "looks" like other very small brown dwarfs. Based on modeling, they estimate a mass of ~6 Jupiter masses, which is small compared to other brown dwarfs. So they are calling it an L dwarf at the moment, which is technically a brown dwarf, but the object is the size of a large planet. But the line between big planet and little star is very fuzzy like I said,

.... what's really fascinating is that all the news articles have been calling this a "rogue planet", or "free-floating planet", when the astronomers actually never call it a planet in their paper. They say they have found a "planetary-mass L dwarf", aka a really small brown dwarf. They compare it to other directly imaged planets, but one of their main points is that many objects that we know are planets actually have similar properties to this object they found, which is more likely a brown dwarf. And they argue that we must be careful not to solely look at the IR properties of objects to determine whether or not they are planets or brown dwarfs, as their IR properties overlap a lot. The media has misinterpreted their discovery a little bit in my opinion. But still very cool. Ok opinion column over.

From the highest volcano to the deepest canyon, from impact craters to ancient river beds and lava flows, this showcase of images from ESA's Mars Express takes you on an unforgettable journey across the Red Planet.

Mars Express was launched on 2 June 2003 and arrived at Mars six-and-a-half months later. It has since orbited the planet nearly 12 500 times, providing scientists with unprecedented images and data collected by its suite of scientific instruments.

The data have been used to create an almost global digital topographic model of the surface, providing a unique visualisation and enabling researchers to acquire new and surprising information about the evolution of the Red Planet.

The images in this movie were taken by the High Resolution Stereo Camera and the video was released by the DLR German Aerospace Center as part of the ten years of Mars Express celebrations in June 2013.

Doesn't seem like spam, doesn't seem like it could possibly not be spam...