Hubble Space Telescope picture of comet C/2019 Y4 (ATLAS), taken on April 20 2020, supplying the sharpest view to date of the break up of the solid nucleus of the comet. Hubbles eagle-eye view recognizes as numerous as 30 different fragments, and distinguishes pieces that are approximately the size of a home. Before the separation, the whole nucleus of the comet may have been the length of a couple of football fields. The comet was roughly 91 million miles (146 million kilometers) from Earth when the image was taken. Credit: NASA/ ESA/ STScI/ D. Jewitt (UCLA).
A serendipitous flythrough of the tail of a disintegrated comet has actually offered researchers a distinct chance to study these remarkable structures, in new research study provided today at the National Astronomy Meeting 2021.
Comet ATLAS fragmented prior to its closest technique to the Sun in 2015, leaving its previous tail trailing through area in the form of wispy clouds of dust and charged particles. The disintegration was observed by the Hubble Space Telescope in April 2020, however more recently the ESA spacecraft Solar Orbiter has flown near to the tail residues in the course of its continuous mission.
This lucky encounter has presented researchers with a distinct chance to examine the structure of an isolated cometary tail. Using combined measurements from all of Solar Orbiters in-situ instruments, the scientists have reconstructed the encounter with ATLASs tail. The resulting model suggests that the ambient interplanetary electromagnetic field carried by the solar wind drapes around the comet, and surrounds a central tail area with a weaker electromagnetic field.
Data from this encounter is expected to contribute significantly to our understanding of the interaction of comets with the solar wind and the structure and formation of their ion tails.
Hubble Space Telescope image of comet C/2019 Y4 (ATLAS), taken on April 20 2020, providing the sharpest view to date of the breakup of the solid nucleus of the comet. The comet was roughly 91 million miles (146 million kilometers) from Earth when the image was taken. The resulting model suggests that the ambient interplanetary magnetic field brought by the solar wind drapes around the comet, and surrounds a main tail area with a weaker magnetic field.
Comets are typically defined by two different tails; one is the popular brilliant and curved dust tail, the other– generally fainter– is the ion tail. The ion tail stems from the interaction in between the cometary gas and the surrounding solar wind, the hot gas of charged particles that constantly blows from the Sun and penetrates the whole Solar System.
When the solar wind communicates with a strong barrier, like a comet, its electromagnetic field is believed to bend and curtain around it. The simultaneous presence of electromagnetic field draping and cometary ions released by the melting of the icy nucleus then produces the particular 2nd ion tail, which can extend for big ranges downstream from the comets nucleus.
Lorenzo Matteini, a solar physicist at Imperial College London and leader of the work, states: “This is quite an unique occasion, and an exciting chance for us to study the makeup and structure of comet tails in unmatched information. Ideally, with the Parker Solar Probe and Solar Orbiter now orbiting the Sun closer than ever before, these occasions may become a lot more common in the future!”.
This is the very first comet tail detection taking place so close to the Sun– well inside the orbit of Venus. It is also among the very few cases where scientists have actually been able to make direct measurements from a fragmented comet. Data from this encounter is anticipated to contribute significantly to our understanding of the interaction of comets with the solar wind and the structure and development of their ion tails.
Fulfilling: Royal Astronomical Society National Astronomy Meeting.