First Observations of Mars Atmosphere and Ionosphere with Tianwen-1 Radio-Occultation Technique on 5 August 2021
, Xiaocheng Wu 1, Shuli Song 2, Maoli Ma 2, Weili Zhou 2, Qingchen Xu 1, Lei Li 1, Cunying Xiao 3, Xie Li 4, Chi Wang 1, Qinghui Liu 2, Lue Chen 4, Guangming Chen 4, Jianfeng Cao 4, Mei Wang 4, Peijia Li 2, Zhanghu Chu 2, Bo Xia 2, Junfeng Yang 1, Cui Tu 1, add
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Ildiko Horvath
Round 1
Reviewer 1 Report
Comments to the manuscript remotesensing-1749092
First observations of Mars atmosphere and ionosphere with Tianwen-1 radio occultation technique on August 5, 2021
by Xiong Hu, Xiaocheng Wu, Shuli Song, Maoli Ma, Weili Zhou, Qingchen Xu, Lei Li, Cunying Xiao, Xie Li, Chi Wang, Qinghui Liu, Lue Chen, Guangming Chen, Jianfeng Cao, Mei Wang, Peijia Li, Zhanghu Chu, Bo Xia, Junfeng Yang, Cui Tu, Dan Liu, Simin Zhang, Quan Zhang, Zheng Li
The Chinese Academy of Sciences, together with various organizations, is conducting intensive space research. This paper, prepared by a team of 24 authors, presents the results of measurements on the Tianwen-1 satellite. The authors implemented the one-way single-frequency RO technique to obtain vertical profiles of atmospheric and ionospheric properties. The results are important and interesting and can be published in a journal. However, I would like to ask a few questions. Questions 1. Line 111: maybe instead of negative it should be related? It is not clear how formulas (3) are used? If SNR is known, then σÏ• is known. On the other hand, Ï•Doppler is known from the measurement. What role does the right-hand side play here? 2. How long does it take to process such an experiment? 3. How often can such measurements be implemented? Because it is desirable to repeat such measurements, especially since the results obtained differ from those of previous experimental and theoretical work. A small remark is reduced to the use of the same symbol L for different quantities (lines 79, 166, 200).
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Author Response
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Reviewer 2 Report
General Comments:
Overall, the manuscript is very well written, very interesting, and reports a new methodology developed for probing the ionosphere and atmosphere of Mars along with the observational results.
The manuscript needs minor revisions (see Detailed Comments below).
Detailed Comments:
L14-15: “ionosphere and atmosphere parameters” should read “ionospheric and atmospheric parameters,”
L17: “Mars ionosphere and atmosphere” should read “Mars ionospheric and atmospheric parameters”
L33: “arrives the receiver” should read “arrives at the receiver”
L39: “the Mars” should read “Mars”
L39: “, which was” should read “and was”
L46: “VLBI” should be defined here
L46: “(31°N, 121°E)” should read “(31°N, 121°E; geographic)”
L53: “in literatures” should read “in the literature”
L62: “in literature” should read “in the literature”
L78: “UTC” should be defined here
L90: “as below” should read “as specified below”
L96: “in literatures” should read “in the literature”
L98: “in one-way RO” should read “in the one-way RO”
L119: “are sphere symmetry” should read “are sphere symmetric”
L120: “in Figure 1” should read “shown in Figure 1”
L128: “sphere symmetry” should read “sphere symmetric”
L133: “in Figure 1” should read “shown in Figure 1”
L149: “by the integration below” should read “by the integration specified below”
L152: “a priori” should read “a prior”
L154: “gravity acceleration” should read “gravitational acceleration”
L164: “defocusing lose” should read “defocusing loss”
L173: “in the” should read “to the”
L181: “signal to noise radio” should read “signal to noise ratio”
L184: “data is” should read “data are”
L185: “1.18mhz” is it milli or mega and “hz” should read “Hz”
L195: “in Figure 2(b).” should read “as shown in Figure 2(b).”
L204: “in Figure 3(a).” should read “shown in Figure 3(a).”
L205: “a dispersion medium” should read “a dispersive medium”
L206: “a non-dispersion medium” should read “non-dispersive medium”
L208-209: “ionosphere height ranges” should read “ionospheric height ranges”
L212: “is in the” should read “are in the”
L213: “Equation (12) and (13).” Should read “Equations (12) and (13).”
L216: “3.3. Mars ionosphere electron density profile” should read “3.3. Mars ionospheric electron density profile”
L218: “in Figure 3(c) by Equation (8) as” should read “shown in Figure 3(c) and specified by Equation (8), as”
L221: “is photo-chemical equilibrium” should read “is in photo-chemical equilibrium”
L221: “depends on solar” should read “depends on the solar”
L225: “weak in Figure 4” should read “weak, as shown in Figure 4”
L226: “is related with the” should read “is related to the”
L228: “have carried out the gravity waves” should read “have specified the gravity waves”
L229-230: “the atmosphere gravity waves” should read “the atmospheric gravity waves”
L231: “atmosphere gravity waves” should read “atmospheric gravity waves”
L240; “3.4. Mars atmosphere profiles” should read “3.4. Mars atmospheric profiles”
L241: “in Figure 3(b)” should read “shown in Figure 3(b”
L244: “for a priori knowledge” should read “based on prior knowledge”
L245: “away with Equation (10)” should read “away, as given with Equation (10)”
L247: “in Figure 5(a) and (b).” should read “shown in Figures 5(a) and (b)”.\
L277: “atmosphere density” should read “atmospheric density”
L278: “features of exponential decreasing with height” should read “features of exponential decreases with height”
L283: “are expected for further Mars science discoveries” should read “are expected to yield further Mars science discoveries”
Author Response
Please see the attachment.
Author Response File: Author Response.docx
