Telescopes are usually trained directly upon a celestial object in order to get the best possible view. But some objects, such as neutron stars, are so complex that a regular image doesn’t provide enough information. Stars have so much energy that is invisible to the naked eye that it can be very difficult to determine the amount of energy, the direction it’s moving in, and the speed of the mass contained in these objects.
Neutron stars are interesting but especially difficult to properly view. They are formed after a supernova of stars of a certain size. These exploding stars are larger than the sun, but not so big as to form a black hole. The massive amount of energy dispelled by a supernova blasts an unbelievable amount of mass around the galaxy, which is called a nebula. Gravity causes this energy to slowly reform into a neutron star. The all the gas of the nebula, which is certainly beautiful, conceals most of the neutron star, which is why a conventional telescope has difficulty seeing many of the finer details.
Neutron stars and nebulas start out spinning extremely rapidly, generates a massive magnetic field in a wide arc. The magnetic field accelerates charged particles, which then emit light in pulses. These light pulses are in multiple parts of the light spectrum, from visible light through gamma radiation, and it’s these gamma radiated particles that astronomers are looking at to better understand neutron stars and supernovas.
Have I lost anyone yet? It’s complex stuff, but essentially a star explodes, and all the energy causes radiation to spin around the cosmos, some of which hits earth’s atmosphere and can be seen using specialized telescopes.
The Crab Nebula is the focus of this new study. About 1000 years ago a star went supernova, leaving behind the Crab Nebula. Energized particles from the nebula hit earth’s atmosphere moving faster than the speed of light. Upon their collision with earth these particles rapidly slow down, giving off a form of light called Cherenkov radiation.
To look at this radiation a telescope called VERITAS, which consists of four 12m telescopes, is focused on earth’s atmosphere, and is able to measure the amount of light from these tiny radiated particles to provide information about their direction and amount of energy, which can be reconstructed to show their origin.
But why does all this matter? Well, the preliminary findings show that some of our previous observations and conclusions about neutron stars may be incorrect. One of these possibly incorrect conclusions is about the exponential decay in pulse energy. The energy from the Crab Nebula is not decaying as quickly as it should, based on prior findings. It also starts out more powerful than previously thought possible. This information gives us new clues as to how stars, galaxies, solar systems and planets are formed, so we may have a better understanding of how our own planet came to be. Using these new findings astronomers may start looking at higher energy wavelengths when viewing nebulas to get a better idea of how they form.
There is a possibility that the Crab Nebula is an anomaly, so doing similar tests on other nebulas is necessary before any of this evidence can be considered conclusive. This might prove difficult, as the Crab Nebula is one of the closest and youngest nebulas in the universe, and the readings from other nebulas may be less reliable.
It’s amazing to see how much work goes into determining the speed of celestial objects. All this astrophysics really shows how much we can learn by using a telescope to look parts of the earth to see the smallest parts of some of the biggest objects in the universe. It’s a bit over my head, but then I tend to think radar guns use some level of wizardry to find how fast a baseball moves.
If you want to take a look at nearby nebulae, I’d suggest investing in a dobsonian telescope with a large aperture. The large aperture will collect enough light to allow you to see detail, and even color of some of the gorgeous nebula in our part of the universe. The Orion Nebula is one of the easiest to see for newer astronomers. The Meade 115mm ED TRIPLET APO f/7 Refractor Telescope is brand new to OpticsPlanet and features a 4.5” aperture, fully multi-coated lenses (for greater light transmission), and an 8X50 viewfinder for an excellent image when checking out a wide variety of celestial bodies, including nebulas. Meade has decades of experience making top quality optics for amateur astronomers. The high value of telescopes by Meade has made them particularly popular, but Meade Binoculars are also very successfully used by nighttime sky watchers throughout the world.