Solar Orbiter’s unique vantage point recently allowed researchers to make a crucial observation of the solar system’s innermost world.
You never know when a chance for some extra space science will present itself. Recently, European Space Agency (ESA) mission controllers had just such a chance, when the planet Mercury passed in front of our host star as seen from the Solar Orbiter’s point of view in space.
Can other planets have geomagnetic storms, even if their magnetosphere is weak and they don’t have an ionosphere like Earth? This question has now been answered, according to research done by a team of scientists in the United States, Canada, and China.
The research team found evidence that Mercury has a ring current, part of a magnetosphere, consisting of charged particles flowing laterally in a doughnut shape around the planet but that excludes the poles. This evidence came from data obtained from the Messenger space probe while it was dropping towards the planet at the end of its mission on April 14, 2015.
Although the Arecibo radio telescope is no more, it continues to deliver scientific discoveries. There is a wealth of Arecibo data astronomers continue to mine for new discoveries, and one of them is thanks to an astronomical technique known as planetary radar.
Some planets orbit their stars so closely that they have extremely high surface temperatures and extremely rapid orbits. Most of the ones astronomers have found are Hot Jupiters— planets in the size range of Jupiter and with similar compositions as Jupiter. Their size and proximity to their star make them easier to spot using the transit method.
But there’s another type of planet that also orbits very close to their stars and has extremely high surface temperatures. They’re small, rocky, and they orbit their star in less than 24 hours. They’re called ultra-short-period (USP) planets and TESS found one that orbits its star in only eight hours.
And the planet’s density is almost equivalent to pure iron.
BepiColombo recently had its first close flyby of Mercury, its eventual mission target, and got to snap some pictures to commemorate the event. Even at this early stage of the mission, these images are some of the clearest we have ever had of the innermost planet.
BepiColombo made a quick visit to Venus in August and is on to its next rendezvous. On October 1st it’ll perform a flyby of Mercury, the spacecraft’s eventual destination. This visit is just a little flirtation—one of six—ahead of its eventual orbital link-up with Mercury in late 2025.
The quick visit will yield some scientific results, though, and they’ll be just a taste of what’s ahead in BepiColumbo’s one-year mission to Mercury.
So much in the astronomy community revolves around the decadal survey. Teams of dozens of scientists put hundreds of hours developing proposals that eventually try to impact the recommendations of the survey panel that influence billions of dollars in research funding over the following decade. And right now is the prime time to get those proposals in. One of the most ambitious is sponsored by a team led by researchers at John Hopkins University Applied Physics Laboratory (APL). Their suggestion – it’s time to land on Mercury.
Astronomers have an excellent habit of naming large projects after deserving contributors to their field. From Nancy Grace Roman to Edwin Hubble, some of the biggest missions are named after space exploration pioneers. When ESA and JAXA sat down to figure out a name for their new Mercury probe, they would have come across an important name early in their research – Giuseppe “Bepi” Colombo – the man who helped plan the Mariner 10 Mercury mission.
Magnetic fields are great for lots of things – directing explorers, levitating trains, and containing nuclear fusion reactions are just an example of what these invisible forces can do. Now we can ascribe another feature to magnetic fields – they can give planets a rocky core.