Jupiter’s New Moons

Yesterday, space nerds were alerted to the news that 12 new moons have been discovered in orbit of Jupiter. These are much smaller than Jupiter’s moon Ganymede, which is the largest moon in the Solar System and is larger than even Mercury. The point is that there are almost certainly no Ganymede-esque moons orbiting Jupiter that remain undiscovered.

But despite their small size, these moons do have some interesting features, as the article I read in the Guardian pointed out. The most interesting is the orbit of the moons. In general, Jovian moons orbit either prograde, i.e. with the orbit of Jupiter, or retrograde, i.e. against the orbit of Jupiter. The two inner moons discovered are prograde and nine of the other 12 are in an outer orbit of retrograde moons. But Valetudo, the 12th, which orbits in the retrograde group, actually orbits in a prograde fashion. The graphic below from the Carnegie Science Institute does a pretty good job of showing this.

Consider this your collision warning
Consider this your collision warning

Ultimately this means that at some point in the future, Valetudo will slam head-on collision style with another Jovian moon. And reportedly that will be so intense we will be able to see it from Earth. Bangin’. Catch is that it will not likely happen anytime soon.

As for the graphic above, I am of two minds. I generally like the use of colour. The bright green contrasts starkly against the red—though it should be pointed out it would fail a red-green colour blindness test. And then the interesting, but admittedly less interesting prograde and previously discovered Galilean moons are in more muted blues and purples, which puts them further into the background. It works nicely as a complete package.

But should it be on a deep blue background? Lots of space visualisations use black backgrounds, including my work and the work of others. But sometimes work that uses a white or otherwise light background could more clearly show things like orbits. It is difficult to say with certainty because of the lack of a light background for comparison’s sake.

The other thing that gets to me is the viewing angle of the orbits. Clearly we are looking neither dead-on nor from high above. And that makes it a bit more difficult to compare orbits. Of course these might not all be on the same plane because orbits are in three-dimensional space. But if the orbits were all shown from above, it would certainly aid with problems of foreshortening.

All in all, though, I shan’t complain because we have more moons in the Solar System. And who knows how many more smaller moons both Jupiter and Saturn have.

Credit for the piece goes to Roberto Molar Candanosa.

The James Webb Telescope: Delayed Again

A few weeks ago it was announced that NASA’s James Webb space telescope would see its launch delayed again. The successor to the Hubble telescope was originally supposed to launch several years ago, but now it won’t fly until at least 2021. Thankfully xkcd covered this slipping launch date.

Sad trombone
Sad trombone

Credit for the piece goes to Randall Munroe.

The Brightest Night Lites

Today is Friday. We all made it through yet another week. So let us look up into the evening sky tonight and see the Hertzsprung–Russel diagram in action. Or, we can take xkcd’s expanded version and just enjoy ourselves.

Alas, I too am in the lower right corner…
Alas, I too am in the lower right corner…

Credit for the piece goes to Randall Munroe.

Lunar Observations

Monday night I was doing some work outside and when I turned around to head inside I was struck by the brilliance of an object in the night sky. I had seen the Moon rise earlier in the evening, but this was far to the east. It was identifiable as a dot, not just a speck in the night sky. As I was now intrigued I went to grab my binoculars to see if I could see Venus.

Turns out I was wrong and it was Jupiter. But then I turned my binocular-aided eyes to the west and examined the Moon. That was then I decided to try and sketch my observations, as I had done with the Eclipse.

Unfortunately, it turns out it is far more difficult to sketch in the dark then under a still semi-sunny sky. But these are my attempts to digitise those observations. And as I sat and watched, I began to notice that some faint twinkling specks near Jupiter had also moved. After I came inside, I discovered that the movement and positions hewed close to the orbits of Jupiter’s moons Ganymede and Calisto. The moving speck near the Moon I had also observed was actually the bright star Regulus. (And to be fair, it had not really moved, the Moon had moved, but I was not redrawing the Moon.)

The Moon and Regulus. The cool part is the thin ring of one of the seas that could be spotted beyond the line separating lunar day from night.

Capturing the exact shapes of the lunar "seas" was difficult in the darkness.
Capturing the exact shapes of the lunar “seas” was difficult in the darkness.

Jupiter and two of its moons. The cool thing about Jupiter is just being able to see it as a round ball in space and not a distant twinkling speck.

Jupiter and two of its moons, as they orbit the distant planet
Jupiter and two of its moons, as they orbit the distant planet

Credit for these is mine.

Onwards and Upwards

Yesterday SpaceX launched the Falcon Heavy rocket on its maiden voyage, and then recaptured several, though not all, of its reusable rockets. The Falcon Heavy represents the most powerful rocket available to mankind today, though NASA’s Saturn V of the Apollo programme era was considerably more powerful. That was all the stuff you could read in the news yesterday and today.

But how much more powerful? Thankfully we have the Economist who put together a nice graphic detailing not just the standard size comparisons of the Falcon series to the Saturn V and other famous rocket systems, e.g. the Space Shuttle and its boosters. The Economist graphic also adds information about the payload capabilities and timeframes for either historical operation or expected service dates.

It's big and powerful, but SpaceX still has a long way to go…
It’s big and powerful, but SpaceX still has a long way to go…

From the illustrative side, there were three really nice touches. First, the faint Statue of Liberty to give the rocket height context to famous landmark buildings. Two, the little human figure on the left-hand side to give context to ourselves, these things are big. Three, the ridiculousness of the Saturn V is captured by having its peak break the top frame of the chrome or graphic device, i.e. the red bar, standard on Economist graphics.

Overall a solid piece. (Yes, I know these are liquid fueled.)

Credit for the piece goes to the Economist’s graphics team.

Farewell, Cassini

Today’s post is a sad post, hence why I did not run with it on Friday. But on Friday, we bid adieu to the little space probe that could, Cassini. This piece is not terribly heavy on the information design, but it does include one diagram—so it counts.

The BBC put together a piece reflecting on the Cassini mission, including its little lander Huygens. If you, like your author, are interested in space-y things, this article is worth the read.

Oh the photos we've enjoyed…
Oh the photos we’ve enjoyed…

Credit for the piece goes to Sue Bridge.

The Timeline of the Voyager Mission

There are a bunch of things to look at this week, but what am I most excited about? Voyager. No, not Star Trek. (Did you know that the Vger entity from the first Star Trek film was a replica of the Voyager probes?) I am of course talking about the Voyager mission to the outer Solar System and beyond.

40 years ago today Voyager 1 lifted off from Cape Canaveral—Voyager 2 left two weeks earlier, but would reach Jupiter and Saturn after Voyager 1, hence being named 2—and it has been collecting images and data for science ever since.

On 25 August 2012, Voyager 1 emerged from the heliosheath and entered interstellar space. In other words, Voyager 1—and sometime in the next few years perhaps—is the first manmade spacecraft to ever leave the Solar System. Mankind is finally out there among the stars.

I love space things.

So JPL and NASA put together this interactive timeline of the mission, which of course continues tomorrow and for years after today until their nuclear fuel runs out.

Boldly going…
Boldly going…

Credit for the piece goes to JPL and NASA.

Solar Eclipse Day

Today is Solar Eclipse Day.

Thankfully Vox has put together a great interactive piece to help you plan your day. This is for my viewing area in Philadelphia. We only max out at 75% of the sun, but that is still pretty fantastic.

I'm totally excited for this
I’m totally excited for this

Credit for the piece goes to Casey Miller, Ryan Mark, and Brian Resnick.

Seven More Planets

What else did you guys think I was going to cover today? The by-elections in Copeland and Stoke? Well, yeah, we’ll likely get back to that tomorrow when we have some results. In the meantime…space!

This is an animation from the New York Times about the Trappist-1 system that has seven Earth-sized planets, a few of which could support liquid water. And since life as we know it depends upon liquid water…well, you get the idea. Go space.

So there's Doc, Dopey, Bashful…wait, wrong group of seven
So there’s Doc, Dopey, Bashful…wait, wrong group of seven

Credit for the piece goes to Neeti Upadhye.

New Neighbours

Among the many, many stories that broke during my month-long radio silence, I got fairly excited about the discovery of a planet orbiting Proxima Centauri. And not just any planet, but a likely rocky planet within the star’s habitable zone. Put that all together and there is the possibility that the planet could host life as we know it. How can that not be exciting? Thankfully the Guardian put together a graphic to support an article detailing the discovery.

Our newest neighbour
Our newest neighbour

Credit for the piece goes to the Guardian’s graphics department.