Of all the inner planets, only Mercury hasn’t had a probe land on it. It likely won’t for quite some time. The reason isn’t because of lack of desire, or worthy science to be done, but because of a simple thing known as delta-v.
Touchdown
This week the Rosetta probe will release Philae to land on the comet 67P/Churyumov-Gerasimenko. It will be the first soft landing on a comet, but not the first probe to land on another world. Besides our homeworld, humans have walked on the surface of one other body and landed probes on five. If successful Philae will mark the 6th solar system object we’ve landed upon.
Approximate Pluto
Just how big is Pluto? The answer is we aren’t entirely sure. We know the diameter is between 2,300 and 2,400 kilometers, but it’s hard to pin down beyond that.
Forever Alone
A plutino is an asteroid-sized body that orbits the Sun in a 2:3 resonance with Neptune. They are named after Pluto, which also orbits the Sun twice for every three orbits of Neptune. It is thought that Pluto and the other plutinos were clustered into this resonance during the migration of the outer planets during the early solar system.
Dust in the Wind
With all the news about Voyager 1 leaving the heliosphere and entering interstellar space you might think that the probe is the first spacecraft to detect interstellar particles. That isn’t entirely true, and the latest observations of interstellar particles has found some very interesting results.
Elvis Has Left the Building
Last year Voyager 1 has left our solar system. Kind of, depending on how you look at it. There were lots of stories in the news about how NASA officially announced that Voyager 1 has left our solar system, but the actual announcement was that the probe has crossed what is known as the heliopause.
Mars Opposition
No, Mars will not appear as big as the Moon tomorrow night. I’m sure that’s a fact most of you already know, but the rumor has made its annual return to social media, so I figure it’s worth stating again. The image you see above, as well as other similar images, is fake.
Ancient Rings
Saturn is everyone’s favorite ringed planet. It’s ring system is both complex and extraordinarily bright. Just why it is so bright has been a bit of a mystery. It’s brightness is due to the fact that the rings are composed almost entirely of water ice, and the fact that there isn’t a great deal of dust in the rings. Because of this, it was once thought that Saturn’s rings were generally young. If the ring system were old, one would expect it to darken over time as dust and other debris from the solar system accumulate over time. This also agreed with the idea that such a complex ring system would likely be unstable over millions of years.
Land of Lakes
For the past week I’ve been in a remote part of northern Minnesota, vacationing at my Grandmother’s house. In that part of world you can pretty much throw a stick and hit a lake, which is part of the reason it is known as the Land of 10,000 lakes. Being in a region with so much water tends to give the impression that Earth is water-rich world.