Space and Astronomy in general

That's great! The article also explains the early timing of the solar array deployment was due to the accuracy of the launch trajectory.

I see that the temperature data is now available at WhereisWebb

Nice. And an explanation for the early deployment. Rocket launch was just too on target hehe.

Robear wrote:

I just go to this page and it has links to everything. Like a mission dashboard.

Up one level from that is the Webb main page, with a link to their blog. That's where you can find the latest news, like that the Tower was successfully deployed today along with the article that badferret posted earlier.

Stele wrote:

Nice. And an explanation for the early deployment. Rocket launch was just too on target hehe.

Yeah, despite the fact that the headline writer at gizmodo said that JWST "Got a Lucky Boost", we have ESA and the Ariane launch team to thank for the potential extra mission time.

I was expecting to hear about the deployment of (at least) one of the two sunshield booms today, but nothing was announced. Should I be concerned?

Apparently not. The port side boom was deployed as of 16:49 EST today. They've started on the starboard side. If that takes as long as the port side it should complete before 22:30 EST.

There was in fact a delay because they were not 100% certain that yesterday's cover retraction was successful.

JWST Blog wrote:

Switches that should have indicated that the cover rolled up did not trigger when they were supposed to. However, secondary and tertiary sources offered confirmation that it had. Temperature data seemed to show that the sunshield cover unrolled to block sunlight from a sensor, and gyroscope sensors indicated motion consistent with the sunshield cover release devices being activated.

After analysis, mission management decided to move forward with the regularly planned deployment sequence.

That's a relief. Love the multiple info source systems.

Robear wrote:

That's a relief. Love the multiple info source systems.

Yeah, no kidding to that. Can you imagine the "oh $#!^" when they saw the first report that said the covers were still in place?

Starboard boom also extended successfully by about 22:13!

I have a friend who ran satellite programming/ops teams at Goddard, so... Yes, yes I can. (I worked for NASA for a few years in the 80's but he did his whole career there.)

The Indian Ocean is the Bermuda Triangle of satellite programs. RIP.

The JWST team deservedly took Saturday off due to the long day on Friday.

Then today they apparently decided to delay further sunshield deployment until Monday so that they could focus on power management today.

It says it's 60% of the distance to L2 but we're only on day 9 of 29 to L2 insertion. Is that because the telescope is significantly slowing down based on gravity pull from sun/earth and thus will cover the remaining 40% much slower?

Yeah the speed like the day after launch was 1.8 miles/sec and now it's down to like .3

Think of throwing a baseball up in a parabola. It's vertical speed diminishes, eventually reaching a standstill, then gaining speed again heading back down. The cool thing here is that the top of the parabola is at a point where gravity is balanced between the earth and the moon. A bit of a nudge and it'll stay up there indefinitely.

That's how I understand it. Hrdina?

Robear wrote:

Think of throwing a baseball up in a parabola. It's vertical speed diminishes, eventually reaching a standstill, then gaining speed again heading back down. The cool thing here is that the top of the parabola is at a point where gravity is balanced between the earth and the moon. A bit of a nudge and it'll stay up there indefinitely.

That's how I understand it. Hrdina?

My over 200 hours of Kerbal Space Program tells me that this explanation is correct.

My kerbals still floating out in space forever can also confirm, Should have grabbed onto that ladder when doing a space walk...

Norfair wrote:
Robear wrote:

Think of throwing a baseball up in a parabola. It's vertical speed diminishes, eventually reaching a standstill, then gaining speed again heading back down. The cool thing here is that the top of the parabola is at a point where gravity is balanced between the earth and the moon. A bit of a nudge and it'll stay up there indefinitely.

That's how I understand it. Hrdina?

My over 200 hours of Kerbal Space Program tells me that this explanation is correct.

And qualifies you for the RocketScientistsOnly dating site.

IMAGE(https://imgs.xkcd.com/comics/orbital_mechanics_2x.png)

Mixolyde wrote:
Norfair wrote:
Robear wrote:

Think of throwing a baseball up in a parabola. It's vertical speed diminishes, eventually reaching a standstill, then gaining speed again heading back down. The cool thing here is that the top of the parabola is at a point where gravity is balanced between the earth and the moon. A bit of a nudge and it'll stay up there indefinitely.

That's how I understand it. Hrdina?

My over 200 hours of Kerbal Space Program tells me that this explanation is correct.

And qualifies you for the RocketScientistsOnly dating site.

Professionally I work on payloads. I'm only a Rocket Scientist in KSP.

I imagined throwing a ball up a parabola, then when it reaches the top of its arc it comes to rest on a power line, perfectly balanced.

Agathos wrote:

IMAGE(https://imgs.xkcd.com/comics/orbital_mechanics_2x.png)

That image needs to be amended with a point for "Watched Quill18's Photoshop Guide to Orbital Mechanics on Youtube". That was seriously enlightening.

Couldn't find that on YouTube. Did you mean Scott Manley's orbital mechanics on paper?

Maybe this one?

Nice! Good to see the devices working as planned.

Mixolyde wrote:

Couldn't find that on YouTube. Did you mean Scott Manley's orbital mechanics on paper?

From the beginning through 15:00ish, then again from about 52:00 through 55:00. Looking at it again now, it doesn't cover nearly as much as I thought it did, but the presentation format itself is what stuck with me, and made sense.

What technology/frequency do they use to communicate with the telescope? Like, if a terrorist hacker wanted to hack the telescope, set its trajectory to enter the earth's gravitational pull, and eventually come crashing into Earth, what's preventing them? The fact that the telescope is such a small entity in a huge solar system, would it be hard to communicate with it without knowing its precise trajectory? A huge apparatus is needed to send those communications effectively limiting the ability to communicate to a few countries? Encryption?

There's an extensive body of academic work on secure radio comms. This is not a new problem.

Sync your calendar with the solar system

You click and it adds the dates to your calendar. Pretty slick.

Jonman wrote:

There's an extensive body of academic work on secure radio comms. This is not a new problem.

Makes sense. I just thought as the price point of these missions increase into the billions and competing countries begin their own space race, I wonder how this might become a factor.

Heavily encrypted communications from the ground station and air-gapped ground station networks with one-way optical links for data export. No security system is perfect, obviously, but they are pretty good.

One of the few moments of excitement I have during these times is I just cannot wait for the photos/science to come in from Webb!

bigred wrote:
Jonman wrote:

There's an extensive body of academic work on secure radio comms. This is not a new problem.

Makes sense. I just thought as the price point of these missions increase into the billions and competing countries begin their own space race, I wonder how this might become a factor.

Honestly, if I was your terrorism advisor, I'd be asking why you're bothering with Webb when there's a bajillionty easier targets in low Earth orbit.