- 2188 - The satellite BepiColombo is sending back new information about the planet Mercury. The satellite is carrying 275 pounds of scientific instruments in a 2.3 hour orbit. Only two spacecraft have visited the planet before BepiColombo arrived October 2018. Mariner 10 arrived in March 1974. The mission of measurements is designed to last until May 2027.
-
-
----------------------------- 2188 - Planet Mercury
-
- The satellite BepiColombo is sending back new information about the planet Mercury. It is our Solar System’s smallest of the eight planets. Yet it has the largest core relative to its size. Its temperatures vary from + 800 F that would melt lead to -290 F even though being the planet closest to the Sun.
-
- Mercury’s orbit is very eccentric. At its closest to the Sun it is 29 million miles away . Its orbit stretches out to 43 million miles away. The Earth is a near steady 93 million miles away in its orbit.
-
- Only two spacecraft have visited the planet before BepiColombo arrived October 2018. Mariner 10 arrived in March 1974.
-
- Mercury’s rotation day is once every 58.6 days, which is 2/3 rds of its orbital period. Mercury spins on its axis 3 times for every 2 solar orbits. In other words a day on Mercury lasts twice as long as its year. There is a new sunrise every 176 days.
-
- Mercury is only 3,032 miles in diameter, which has barely enough gravity to retain a small atmosphere. The atmosphere is a thin layer of loosely bound atoms, mostly hydrogen and helium, captured from the solar wind. Traces of oxygen also exist as these atoms are liberated from the surface by micrometeoroid impacts. Many more elements were found in this same debris.
-
- Mercury’s density is 5.4 times that of water. Earth is 5.5 and Venus is 5.2. But these much larger planet masses can crush their interiors into these high densities. Mercury is half their size but its core appears to be 70% heavy elements like iron and nickel. Mercury’s heavy core reaches to within 250 miles of its surface.
-
- Mercury’s magnetic field is feeble just 1% the strength of Earth’s. But it does suggest that Mercury has a partially molten outer core. Likely that radioactive elements are keeping the core electrically conducive and in a semi-liquid state.
-
- Also, Mercury’s elongated orbit causes Sun’s gravity to flex the interior creating another source of heat..
-
- Permanently shadowed craters allow temperatures to drop to -370 F and discoveries have been calculated for some craters to contain over 1 trillion tons of water ice. Although being the planet closest to the Sun Mercury boasts some of the coldest spots in the Solar System.
-
- Catching an orbit around Mercury is no easy task. The rocket energy to put on the brakes is more than that needed to take another craft all the way to Pluto. Mercury’s orbital speed is 105,900 miles per hour. This requires the craft to have a very big velocity change.
-
- The total trip will take the spacecraft 1.5 circuits of the Sun returning to Earth on April, 2020 to get a gravitational boost which will send it to Venus in October 2020 and August 2021. These multiple flybys use gravity instead of rocket fuel to propel the spacecraft. In fact, they represent about one half the total energy needed for the mission.
-
- There will be six flybys of Mercury between October 2021 and January 2025. In December 2025 the BepiColombo spacecraft should be in a polar orbit 420 miles above the planets surface extending to 110,600 miles above. The satellite is carrying 275 pounds of scientific instruments in a 2.3 hour orbit The mission of measurements is designed to last until May 2027. This whole trip will have traveled over 5.5 billion miles.
-
- A side benefit of tracking the spacecraft with precision will be the rigorous test of Einstein’s Theory of Relativity.
-
- Does Albert’s math always work?
-
- Other Reviews available:
-
- 1873 - Venus and Mercury. April 30, 2015, The Messenger space probe crashed into Mercury’s surface crating a 52 foot-wide crater.
-
- 1815 - What did we learn from spacecraft Messenger.
-
- This Review lists 9 more Reviews on the planet Mercury.
-
- November 28, 2018
---------------------------------------------------------------------------------------
---- Comments appreciated and Pass it on to whomever is interested. ----
--- Some reviews are at: -------------- http://jdetrick.blogspot.com -----
-- email feedback, corrections, request for copies or Index of all reviews
- to: ------- jamesdetrick@comcast.net ------ “Jim Detrick” -----------
- https://plus.google.com/u/0/ -- www.facebook.com -- www.twitter.com
-------------------------- Wednesday, November 28, 2018 --------------------------
------------------------------------------------------------------------------------------
No comments:
Post a Comment