AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |
Back to Blog
Astronomical unit calculator12/20/2023 This requires the inner planet be at inferior conjunction along the line formed by the intersection of the Earth’s orbital plane and the planet’s orbital plane (the line of nodes). They occur when a planet (Mercury or Venus) passes in front of the Sun as seen from Earth. This award is being presented in collaboration with NASA. The purpose of this award is to provide an opportunity to relive the excitement of being on a planetary transit expedition and to derive a value for the Astronomical Unit, and to recognize those who participate. Welcome to the Astronomical League's Planetary Transit Special Award site. This is the webpage for those former activites. But for scientific and engineering usage, it is essential to get it right.” – Peter Noerdlinger, astronomer at St Mary’s University, Canada.Ĭorrecting classical “constants” in physics is essential when high accuracy is required to calculate quantities over massive distances or long periods of time, therefore the AU (as it is currently defined) may be demoted as a general description of distance rather than a standard scientific unit.The Venus Transits and the Mercury Transit of 2016 were focused on calculating the value of the A.U. There are now calls to correct for this gradual increase in the value of the AU by discarding it all together. Although a tiny number – astrophysicists are unlikely to lose any sleep over the discrepancy – a universal constant should be just that, constant. It has been calculated that Mercury will lag behind it’s current orbital position in 200 years time by 5.5 km if we continue to use today’s AU in future calculations. The official calculation is based on “k”, a constant based on the estimated constant mass of the Sun. But the mass of the Sun ain’t constant.Īs mass is lost via the solar wind and radiation (radiation energy will carry mass from the Sun due to the energy-mass relationship defined by Einstein’s E=mc 2), the value of the Astronomical Unit will increase, and by its definition, the orbit of the planets should also increase. Mars has an average orbit of 1.5AU, Mercury has an average of about 0.4AU… But how is the distance of one AU defined? Most commonly thought to be derived as the mean distance of the Sun-Earth orbit, it is actually officially defined as: the radius of an unperturbed circular orbit that a massless body would revolve about the Sun in 2Ï€/k days (that’s one year). For instance, one AU is approximately the mean distance from the Sun to Earth orbit (defined as 149,597,870.691 kilometres). The AU is commonly used to describe distances within the Solar System. So, when using the Astronomical Unit (AU), problems will begin to surface in astronomical calculations as this “universal constant” is based on the mass of the Sun… However small the mass loss, the mass of the Sun is not constant. This may seem like a lot, but when compared with the total mass of the Sun (of nearly 2Ã-10 30 kilograms), this rate of mass loss is miniscule. As the burning giant begins a new solar cycle, it continues to lose about 6 billion kilograms (that’s approximately 16 Empire State Building’s worth) of mass per second. Our closest star is shedding material through the solar wind, coronal mass ejections and by simply generating light.
0 Comments
Read More
Leave a Reply. |