Comet C/2021 T4 (Lemmon)

Comet C/2021 T4 (Lemmon) is currently in the constellation of Libra. The current Right Ascension of Comet C/2021 T4 (Lemmon) is 14h 51m 36s and the Declination is -14° 35’ 15” (topocentric coordinates computed for the selected location: Greenwich, United Kingdom edit_location_alt). The current estimated magnitude of Comet C/2021 T4 (Lemmon) is 12.86 (JPL).

The observed values of Magnitude, Coma Diameter and Tail Length are derived from the most recent observation recorded at the Comet Observers Database. The value of Predicted Magnitude comes from the JPL Horizons ephemerides service and, in the case of comets, might be inaccurate given the highly dynamic and unpredictable behavior of these objects. When available, please refer to the Observed Magnitude value and consider the Predicted Magnitude as a directional indication. We acknowledge with thanks the comet observations from the COBS Comet Observation Database contributed by observers worldwide and used in this table to report recent comet observations.

Today's rise, transit and set times of Comet C/2021 T4 (Lemmon) from Greenwich, United Kingdom edit_location_alt (all times relative to the local timezone Europe/London):

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Available Resources

• Position and finder charts (see also Where is Comet C/2021 T4 (Lemmon)?)
• Distance from Earth (see also How far is Comet C/2021 T4 (Lemmon) from Earth?)
• When does Comet C/2021 T4 (Lemmon) rise and set?
• Brightness (see also How bright is Comet C/2021 T4 (Lemmon)?)
• Orbital elements. Detailed information about Comet C/2021 T4 (Lemmon) orbital parameters.
• Interactive orbit visualization. 3d visualization showing the orbit of Comet C/2021 T4 (Lemmon) with respect to the major Solar System objects.
• 15 days ephemerides. Table showing celestial coordinates and magnitude of Comet C/2021 T4 (Lemmon) for the past and next 7 days.
• Interactive sky chart. An online planetarium application that shows where to locate Comet C/2021 T4 (Lemmon) in the sky from your location.
• Live position tracker. A high precision sky chart that uses real deep sky imagery to help locate Comet C/2021 T4 (Lemmon) with your telescope or on your astrophotographies.

Higher precision deep sky finder chart, 60 arcmin wide, showing where Comet C/2021 T4 (Lemmon) is right now. Click on the image to see a more detailed fullscreen tracker view.

Also check out Where is Comet C/2021 T4 (Lemmon)?, a page that provides all the information needed to find Comet C/2021 T4 (Lemmon) in the sky and additional links to sky charts.

Comet C/2021 T4 (Lemmon) Distance from Earth

The distance of Comet C/2021 T4 (Lemmon) from Earth is currently 324,091,375 kilometers, equivalent to 2.166417 Astronomical Units. Light takes 18 minutes and 1.0525 seconds to travel from Comet C/2021 T4 (Lemmon) and arrive to us.

The following chart shows the distance of Comet C/2021 T4 (Lemmon) from Earth as a function of time. In the chart the distance data is measured in Astronomical Units and sampled with an interval of 1 day.

The value of the reported distance might be somewhat inaccurate around the times of closest approach for objects passing extremely close to Earth. The value of the distance of C/2021 T4 (Lemmon) from Earth is also available as a real time updated value in the Live Position and Data Tracker.

Closest Approach of Comet C/2021 T4 (Lemmon) to Earth

Between 1 January 2000 and 31 December 2099, the closest approach of Comet C/2021 T4 (Lemmon) to Earth happens on Fri Jul 21 2023 at a distance of 0.541534 Astronomical Units, or 81,012,307 kilometers:

NOTE: values for the closest approach are computed with a sampling interval of 1 day.

Comet C/2021 T4 (Lemmon) Brightness and Light Curve

The following chart is the predicted light curve (visual magnitude as a function of time) of Comet C/2021 T4 (Lemmon), according to the most recent ephemerides data. Magnitude data is sampled with a 2 days interval and there might be inaccuracies for objects changing brightness very rapidly during the course of a few days. For comets there could be large discrepancies between the observed and predicted brightness because of their highly dynamic behaviour.

Visualization of Comet C/2021 T4 (Lemmon) Orbit

This 3d orbit diagram is a feature of our 3D Solar System Simulator and shows the orbit of Comet C/2021 T4 (Lemmon) with respect of the Sun and the orbits of the major planets. The position of Comet C/2021 T4 (Lemmon) and the planets along their orbits in this diagram accurately represents the current configuration of the objects in the Solar System. This is an experimental feature and it requires a WebGL enabled browser. Please provide us feedback!

Comet C/2021 T4 (Lemmon) 15 Days Ephemeris

The following table lists the ephemerides of Comet C/2021 T4 (Lemmon) computed for the past and next 7 days, with a 24 hours interval. Click on each row of the table to locate Comet C/2021 T4 (Lemmon) in our Online Planetarium at the chosen date.

Date	Right AscensionR.A.	DeclinationDec.	MagnitudeMag	Constellation
2023 Sep 14	14h 51m 20s	-15° 46’ 59”	12.57	Libra
2023 Sep 15	14h 51m 19s	-15° 36’ 20”	12.61	Libra
2023 Sep 16	14h 51m 19s	-15° 26’ 03”	12.65	Libra
2023 Sep 17	14h 51m 19s	-15° 16’ 09”	12.69	Libra
2023 Sep 18	14h 51m 20s	-15° 06’ 33”	12.73	Libra
2023 Sep 19	14h 51m 24s	-14° 57’ 18”	12.77	Libra
2023 Sep 20	14h 51m 28s	-14° 48’ 19”	12.80	Libra
2023 Sep 21	14h 51m 33s	-14° 39’ 38”	12.84	Libra
2023 Sep 22	14h 51m 38s	-14° 31’ 14”	12.88	Libra
2023 Sep 23	14h 51m 45s	-14° 23’ 04”	12.91	Libra
2023 Sep 24	14h 51m 52s	-14° 15’ 10”	12.95	Libra
2023 Sep 25	14h 52m 00s	-14° 07’ 29”	12.98	Libra
2023 Sep 26	14h 52m 09s	-14° 00’ 02”	13.02	Libra
2023 Sep 27	14h 52m 19s	-13° 52’ 48”	13.05	Libra