Daily cosmobite: Earth closest to the Sun
This afternoon at 3:38 pm eastern summer time the Earth is at perihelion, its closest point to the Sun for the year. At this point we are 147.1 million km from the Sun. Though this distance is 5 million km less than the distance at our furthest point in July, it has little effect on the temperature.
January 05, 2013 at 11:16 pm, kirsten said:
Hello.
I am an amateur astronomer from Sydney, (my professional field is nursing), and i am very interested to know how the sun’s magnetic field influences the Earth’s magnetic field. When that of the sun is lesser than normal, as illustrated in your article, how is this reflected in our planets own? What changes in the Earths magnetic field were noted in 2011
January 08, 2013 at 12:06 pm, Nick Lomb said:
Hello Kisten. I presume that you are referring to Harry’s post on the low activity on the Sun at present that is disappointing Sun watchers. The low activity suggests that there less flares and Coronal Mass Ejections (CMEs) on the Sun than is usual near a time of solar maximum. This means aurorae are less commonly seen and when seen they tend not to stray far from the Earth’s magnetic poles. There is also the beneficial effect of less disruption to satellite and other communications, the GPS navigation system and power transmission on Earth.
January 02, 2013 at 9:03 am, Roberto said:
Is the date of perihelion fixed, or does it move gradually over time?
January 02, 2013 at 4:24 pm, Nick Lomb said:
Happy New Year Roberto! The date of perihelion can change from year to year by a day or two due to the the influence of the Moon and the consequences of leap years. In addition, there is a long-term trend for perihelion to occur a day later every 58 years. Hence in about 10 000 years’ time the Earth will reach perihelion in the southern winter instead of its summer.